pragma solidity ^0.5.4;

library RLPReader {
    uint8 constant STRING_SHORT_START = 0x80;
    uint8 constant STRING_LONG_START  = 0xb8;
    uint8 constant LIST_SHORT_START   = 0xc0;
    uint8 constant LIST_LONG_START    = 0xf8;
    uint8 constant WORD_SIZE = 32;

    struct RLPItem {
        uint len;
        uint memPtr;
    }

    struct Iterator {
        RLPItem item;   // Item that's being iterated over.
        uint nextPtr;   // Position of the next item in the list.
    }

    /*
    * @dev Returns the next element in the iteration. Reverts if it has not next element.
    * @param self The iterator.
    * @return The next element in the iteration.
    */
    function next(Iterator memory self) internal pure returns (RLPItem memory) {
        require(hasNext(self));

        uint ptr = self.nextPtr;
        uint itemLength = _itemLength(ptr);
        self.nextPtr = ptr + itemLength;

        return RLPItem(itemLength, ptr);
    }

    /*
    * @dev Returns true if the iteration has more elements.
    * @param self The iterator.
    * @return true if the iteration has more elements.
    */
    function hasNext(Iterator memory self) internal pure returns (bool) {
        RLPItem memory item = self.item;
        return self.nextPtr < item.memPtr + item.len;
    }

    /*
    * @param item RLP encoded bytes
    */
    function toRlpItem(bytes memory item) internal pure returns (RLPItem memory) {
        uint memPtr;
        assembly {
            memPtr := add(item, 0x20)
        }

        return RLPItem(item.length, memPtr);
    }

    /*
    * @dev Create an iterator. Reverts if item is not a list.
    * @param self The RLP item.
    * @return An 'Iterator' over the item.
    */
    function iterator(RLPItem memory self) internal pure returns (Iterator memory) {
        require(isList(self));

        uint ptr = self.memPtr + _payloadOffset(self.memPtr);
        return Iterator(self, ptr);
    }

    /*
    * @param item RLP encoded bytes
    */
    function rlpLen(RLPItem memory item) internal pure returns (uint) {
        return item.len;
    }

    /*
    * @param item RLP encoded bytes
    */
    function payloadLen(RLPItem memory item) internal pure returns (uint) {
        return item.len - _payloadOffset(item.memPtr);
    }

    /*
    * @param item RLP encoded list in bytes
    */
    function toList(RLPItem memory item) internal pure returns (RLPItem[] memory) {
        require(isList(item));

        uint items = numItems(item);
        RLPItem[] memory result = new RLPItem[](items);

        uint memPtr = item.memPtr + _payloadOffset(item.memPtr);
        uint dataLen;
        for (uint i = 0; i < items; i++) {
            dataLen = _itemLength(memPtr);
            result[i] = RLPItem(dataLen, memPtr); 
            memPtr = memPtr + dataLen;
        }

        return result;
    }

    // @return indicator whether encoded payload is a list. negate this function call for isData.
    function isList(RLPItem memory item) internal pure returns (bool) {
        if (item.len == 0) return false;

        uint8 byte0;
        uint memPtr = item.memPtr;
        assembly {
            byte0 := byte(0, mload(memPtr))
        }

        if (byte0 < LIST_SHORT_START)
            return false;
        return true;
    }

    /** RLPItem conversions into data types **/

    // @returns raw rlp encoding in bytes
    function toRlpBytes(RLPItem memory item) internal pure returns (bytes memory) {
        bytes memory result = new bytes(item.len);
        if (result.length == 0) return result;
        
        uint ptr;
        assembly {
            ptr := add(0x20, result)
        }

        copy(item.memPtr, ptr, item.len);
        return result;
    }

    // any non-zero byte is considered true
    function toBoolean(RLPItem memory item) internal pure returns (bool) {
        require(item.len == 1);
        uint result;
        uint memPtr = item.memPtr;
        assembly {
            result := byte(0, mload(memPtr))
        }

        return result == 0 ? false : true;
    }

    function toAddress(RLPItem memory item) internal pure returns (address) {
        // 1 byte for the length prefix
        require(item.len == 21);

        return address(toUint(item));
    }

    function toUint(RLPItem memory item) internal pure returns (uint) {
        require(item.len > 0 && item.len <= 33);

        uint offset = _payloadOffset(item.memPtr);
        uint len = item.len - offset;

        uint result;
        uint memPtr = item.memPtr + offset;
        assembly {
            result := mload(memPtr)

            // shfit to the correct location if neccesary
            if lt(len, 32) {
                result := div(result, exp(256, sub(32, len)))
            }
        }

        return result;
    }

    // enforces 32 byte length
    function toUintStrict(RLPItem memory item) internal pure returns (uint) {
        // one byte prefix
        require(item.len == 33);

        uint result;
        uint memPtr = item.memPtr + 1;
        assembly {
            result := mload(memPtr)
        }

        return result;
    }

    function toBytes(RLPItem memory item) internal pure returns (bytes memory) {
        require(item.len > 0);

        uint offset = _payloadOffset(item.memPtr);
        uint len = item.len - offset; // data length
        bytes memory result = new bytes(len);

        uint destPtr;
        assembly {
            destPtr := add(0x20, result)
        }

        copy(item.memPtr + offset, destPtr, len);
        return result;
    }

    /*
    * Private Helpers
    */

    // @return number of payload items inside an encoded list.
    function numItems(RLPItem memory item) private pure returns (uint) {
        if (item.len == 0) return 0;

        uint count = 0;
        uint currPtr = item.memPtr + _payloadOffset(item.memPtr);
        uint endPtr = item.memPtr + item.len;
        while (currPtr < endPtr) {
           currPtr = currPtr + _itemLength(currPtr); // skip over an item
           count++;
        }

        return count;
    }

    // @return entire rlp item byte length
    function _itemLength(uint memPtr) private pure returns (uint) {
        uint itemLen;
        uint byte0;
        assembly {
            byte0 := byte(0, mload(memPtr))
        }

        if (byte0 < STRING_SHORT_START)
            itemLen = 1;
        
        else if (byte0 < STRING_LONG_START)
            itemLen = byte0 - STRING_SHORT_START + 1;

        else if (byte0 < LIST_SHORT_START) {
            assembly {
                let byteLen := sub(byte0, 0xb7) // # of bytes the actual length is
                memPtr := add(memPtr, 1) // skip over the first byte
                
                /* 32 byte word size */
                let dataLen := div(mload(memPtr), exp(256, sub(32, byteLen))) // right shifting to get the len
                itemLen := add(dataLen, add(byteLen, 1))
            }
        }

        else if (byte0 < LIST_LONG_START) {
            itemLen = byte0 - LIST_SHORT_START + 1;
        } 

        else {
            assembly {
                let byteLen := sub(byte0, 0xf7)
                memPtr := add(memPtr, 1)

                let dataLen := div(mload(memPtr), exp(256, sub(32, byteLen))) // right shifting to the correct length
                itemLen := add(dataLen, add(byteLen, 1))
            }
        }

        return itemLen;
    }

    // @return number of bytes until the data
    function _payloadOffset(uint memPtr) private pure returns (uint) {
        uint byte0;
        assembly {
            byte0 := byte(0, mload(memPtr))
        }

        if (byte0 < STRING_SHORT_START) 
            return 0;
        else if (byte0 < STRING_LONG_START || (byte0 >= LIST_SHORT_START && byte0 < LIST_LONG_START))
            return 1;
        else if (byte0 < LIST_SHORT_START)  // being explicit
            return byte0 - (STRING_LONG_START - 1) + 1;
        else
            return byte0 - (LIST_LONG_START - 1) + 1;
    }

    /*
    * @param src Pointer to source
    * @param dest Pointer to destination
    * @param len Amount of memory to copy from the source
    */
    function copy(uint src, uint dest, uint len) private pure {
        if (len == 0) return;

        // copy as many word sizes as possible
        for (; len >= WORD_SIZE; len -= WORD_SIZE) {
            assembly {
                mstore(dest, mload(src))
            }

            src += WORD_SIZE;
            dest += WORD_SIZE;
        }

        // left over bytes. Mask is used to remove unwanted bytes from the word
        uint mask = 256 ** (WORD_SIZE - len) - 1;
        assembly {
            let srcpart := and(mload(src), not(mask)) // zero out src
            let destpart := and(mload(dest), mask) // retrieve the bytes
            mstore(dest, or(destpart, srcpart))
        }
    }
}

contract Account {

    // The implementation of the proxy
    address public implementation;

    // Logic manager
    address public manager;
    
    // The enabled static calls
    mapping (bytes4 => address) public enabled;

    event EnabledStaticCall(address indexed module, bytes4 indexed method);
    event Invoked(address indexed module, address indexed target, uint indexed value, bytes data);
    event Received(uint indexed value, address indexed sender, bytes data);

    event AccountInit(address indexed account);
    event ManagerChanged(address indexed mgr);

    modifier allowAuthorizedLogicContractsCallsOnly {
        require(LogicManager(manager).isAuthorized(msg.sender), "not an authorized logic");
        _;
    }

    function init(address _manager, address _accountStorage, address[] calldata _logics, address[] calldata _keys, address[] calldata _backups)
        external
    {
        require(manager == address(0), "Account: account already initialized");
        require(_manager != address(0) && _accountStorage != address(0), "Account: address is null");
        manager = _manager;

        for (uint i = 0; i < _logics.length; i++) {
            address logic = _logics[i];
            require(LogicManager(manager).isAuthorized(logic), "must be authorized logic");

            BaseLogic(logic).initAccount(this);
        }

        AccountStorage(_accountStorage).initAccount(this, _keys, _backups);

        emit AccountInit(address(this));
    }

    function invoke(address _target, uint _value, bytes calldata _data)
        external
        allowAuthorizedLogicContractsCallsOnly
        returns (bytes memory _res)
    {
        bool success;
        // solium-disable-next-line security/no-call-value
        (success, _res) = _target.call.value(_value)(_data);
        require(success, "call to target failed");
        emit Invoked(msg.sender, _target, _value, _data);
    }

    /**
    * @dev Enables a static method by specifying the target module to which the call must be delegated.
    * @param _module The target module.
    * @param _method The static method signature.
    */
    function enableStaticCall(address _module, bytes4 _method) external allowAuthorizedLogicContractsCallsOnly {
        enabled[_method] = _module;
        emit EnabledStaticCall(_module, _method);
    }

    function changeManager(address _newMgr) external allowAuthorizedLogicContractsCallsOnly {
        require(_newMgr != address(0), "address cannot be null");
        require(_newMgr != manager, "already changed");
        manager = _newMgr;
        emit ManagerChanged(_newMgr);
    }

     /**
     * @dev This method makes it possible for the wallet to comply to interfaces expecting the wallet to
     * implement specific static methods. It delegates the static call to a target contract if the data corresponds
     * to an enabled method, or logs the call otherwise.
     */
    function() external payable {
        if(msg.data.length > 0) {
            address logic = enabled[msg.sig];
            if(logic == address(0)) {
                emit Received(msg.value, msg.sender, msg.data);
            }
            else {
                require(LogicManager(manager).isAuthorized(logic), "must be an authorized logic for static call");
                // solium-disable-next-line security/no-inline-assembly
                assembly {
                    calldatacopy(0, 0, calldatasize())
                    let result := staticcall(gas, logic, 0, calldatasize(), 0, 0)
                    returndatacopy(0, 0, returndatasize())
                    switch result
                    case 0 {revert(0, returndatasize())}
                    default {return (0, returndatasize())}
                }
            }
        }
    }
}

contract Owned {

    // The owner
    address public owner;

    event OwnerChanged(address indexed _newOwner);

    /**
     * @dev Throws if the sender is not the owner.
     */
    modifier onlyOwner {
        require(msg.sender == owner, "Must be owner");
        _;
    }

    constructor() public {
        owner = msg.sender;
    }

    /**
     * @dev Lets the owner transfer ownership of the contract to a new owner.
     * @param _newOwner The new owner.
     */
    function changeOwner(address _newOwner) external onlyOwner {
        require(_newOwner != address(0), "Address must not be null");
        owner = _newOwner;
        emit OwnerChanged(_newOwner);
    }
}

contract LogicManager is Owned {

    event UpdateLogicSubmitted(address indexed logic, bool value);
    event UpdateLogicCancelled(address indexed logic);
    event UpdateLogicDone(address indexed logic, bool value);

    struct pending {
        bool value;
        uint dueTime;
    }

    // The authorized logic modules
    mapping (address => bool) public authorized;

    /*
    array
    index 0: AccountLogic address
          1: TransferLogic address
          2: DualsigsLogic address
          3: DappLogic address
          4: ...
     */
    address[] public authorizedLogics;

    // updated logics and their due time of becoming effective
    mapping (address => pending) public pendingLogics;

    // pending time before updated logics take effect
    struct pendingTime {
        uint curPendingTime;
        uint nextPendingTime;
        uint dueTime;
    }

    pendingTime public pt;

    // how many authorized logics
    uint public logicCount;

    constructor(address[] memory _initialLogics, uint256 _pendingTime) public
    {
        for (uint i = 0; i < _initialLogics.length; i++) {
            address logic = _initialLogics[i];
            authorized[logic] = true;
            logicCount += 1;
        }
        authorizedLogics = _initialLogics;

        pt.curPendingTime = _pendingTime;
        pt.nextPendingTime = _pendingTime;
        pt.dueTime = now;
    }

    function submitUpdatePendingTime(uint _pendingTime) external onlyOwner {
        pt.nextPendingTime = _pendingTime;
        pt.dueTime = pt.curPendingTime + now;
    }

    function triggerUpdatePendingTime() external {
        require(pt.dueTime <= now, "too early to trigger updatePendingTime");
        pt.curPendingTime = pt.nextPendingTime;
    }

    function isAuthorized(address _logic) external view returns (bool) {
        return authorized[_logic];
    }

    function getAuthorizedLogics() external view returns (address[] memory) {
        return authorizedLogics;
    }

    function submitUpdate(address _logic, bool _value) external onlyOwner {
        pending storage p = pendingLogics[_logic];
        p.value = _value;
        p.dueTime = now + pt.curPendingTime;
        emit UpdateLogicSubmitted(_logic, _value);
    }

    function cancelUpdate(address _logic) external onlyOwner {
        delete pendingLogics[_logic];
        emit UpdateLogicCancelled(_logic);
    }

    function triggerUpdateLogic(address _logic) external {
        pending memory p = pendingLogics[_logic];
        require(p.dueTime > 0, "pending logic not found");
        require(p.dueTime <= now, "too early to trigger updateLogic");
        updateLogic(_logic, p.value);
        delete pendingLogics[_logic];
    }

    function updateLogic(address _logic, bool _value) internal {
        if (authorized[_logic] != _value) {
            if(_value) {
                logicCount += 1;
                authorized[_logic] = true;
                authorizedLogics.push(_logic);
            }
            else {
                logicCount -= 1;
                require(logicCount > 0, "must have at least one logic module");
                delete authorized[_logic];
                removeLogic(_logic);
            }
            emit UpdateLogicDone(_logic, _value);
        }
    }

    function removeLogic(address _logic) internal {
        uint len = authorizedLogics.length;
        address lastLogic = authorizedLogics[len - 1];
        if (_logic != lastLogic) {
            for (uint i = 0; i < len; i++) {
                 if (_logic == authorizedLogics[i]) {
                     authorizedLogics[i] = lastLogic;
                     break;
                 }
            }
        }
        authorizedLogics.length--;
    }
}

contract AccountStorage {

    modifier allowAccountCallsOnly(Account _account) {
        require(msg.sender == address(_account), "caller must be account");
        _;
    }

    modifier allowAuthorizedLogicContractsCallsOnly(address payable _account) {
        require(LogicManager(Account(_account).manager()).isAuthorized(msg.sender), "not an authorized logic");
        _;
    }

    struct KeyItem {
        address pubKey;
        uint256 status;
    }

    struct BackupAccount {
        address backup;
        uint256 effectiveDate;//means not effective until this timestamp
        uint256 expiryDate;//means effective until this timestamp
    }

    struct DelayItem {
        bytes32 hash;
        uint256 dueTime;
    }

    struct Proposal {
        bytes32 hash;
        address[] approval;
    }

    // account => quantity of operation keys (index >= 1)
    mapping (address => uint256) operationKeyCount;

    // account => index => KeyItem
    mapping (address => mapping(uint256 => KeyItem)) keyData;

    // account => index => backup account
    mapping (address => mapping(uint256 => BackupAccount)) backupData;

    /* account => actionId => DelayItem

       delayData applies to these 4 actions:
       changeAdminKey, changeAllOperationKeys, unfreeze, changeAdminKeyByBackup
    */
    mapping (address => mapping(bytes4 => DelayItem)) delayData;

    // client account => proposer account => proposed actionId => Proposal
    mapping (address => mapping(address => mapping(bytes4 => Proposal))) proposalData;

    // *************** keyCount ********************** //

    function getOperationKeyCount(address _account) external view returns(uint256) {
        return operationKeyCount[_account];
    }

    function increaseKeyCount(address payable _account) external allowAuthorizedLogicContractsCallsOnly(_account) {
        operationKeyCount[_account] = operationKeyCount[_account] + 1;
    }

    // *************** keyData ********************** //

    function getKeyData(address _account, uint256 _index) public view returns(address) {
        KeyItem memory item = keyData[_account][_index];
        return item.pubKey;
    }

    function setKeyData(address payable _account, uint256 _index, address _key) external allowAuthorizedLogicContractsCallsOnly(_account) {
        require(_key != address(0), "invalid _key value");
        KeyItem storage item = keyData[_account][_index];
        item.pubKey = _key;
    }

    // *************** keyStatus ********************** //

    function getKeyStatus(address _account, uint256 _index) external view returns(uint256) {
        KeyItem memory item = keyData[_account][_index];
        return item.status;
    }

    function setKeyStatus(address payable _account, uint256 _index, uint256 _status) external allowAuthorizedLogicContractsCallsOnly(_account) {
        KeyItem storage item = keyData[_account][_index];
        item.status = _status;
    }

    // *************** backupData ********************** //

    function getBackupAddress(address _account, uint256 _index) external view returns(address) {
        BackupAccount memory b = backupData[_account][_index];
        return b.backup;
    }

    function getBackupEffectiveDate(address _account, uint256 _index) external view returns(uint256) {
        BackupAccount memory b = backupData[_account][_index];
        return b.effectiveDate;
    }

    function getBackupExpiryDate(address _account, uint256 _index) external view returns(uint256) {
        BackupAccount memory b = backupData[_account][_index];
        return b.expiryDate;
    }

    function setBackup(address payable _account, uint256 _index, address _backup, uint256 _effective, uint256 _expiry)
        external
        allowAuthorizedLogicContractsCallsOnly(_account)
    {
        BackupAccount storage b = backupData[_account][_index];
        b.backup = _backup;
        b.effectiveDate = _effective;
        b.expiryDate = _expiry;
    }

    function setBackupExpiryDate(address payable _account, uint256 _index, uint256 _expiry)
        external
        allowAuthorizedLogicContractsCallsOnly(_account)
    {
        BackupAccount storage b = backupData[_account][_index];
        b.expiryDate = _expiry;
    }

    function clearBackupData(address payable _account, uint256 _index) external allowAuthorizedLogicContractsCallsOnly(_account) {
        delete backupData[_account][_index];
    }

    // *************** delayData ********************** //

    function getDelayDataHash(address payable _account, bytes4 _actionId) external view returns(bytes32) {
        DelayItem memory item = delayData[_account][_actionId];
        return item.hash;
    }

    function getDelayDataDueTime(address payable _account, bytes4 _actionId) external view returns(uint256) {
        DelayItem memory item = delayData[_account][_actionId];
        return item.dueTime;
    }

    function setDelayData(address payable _account, bytes4 _actionId, bytes32 _hash, uint256 _dueTime) external allowAuthorizedLogicContractsCallsOnly(_account) {
        DelayItem storage item = delayData[_account][_actionId];
        item.hash = _hash;
        item.dueTime = _dueTime;
    }

    function clearDelayData(address payable _account, bytes4 _actionId) external allowAuthorizedLogicContractsCallsOnly(_account) {
        delete delayData[_account][_actionId];
    }

    // *************** proposalData ********************** //

    function getProposalDataHash(address _client, address _proposer, bytes4 _actionId) external view returns(bytes32) {
        Proposal memory p = proposalData[_client][_proposer][_actionId];
        return p.hash;
    }

    function getProposalDataApproval(address _client, address _proposer, bytes4 _actionId) external view returns(address[] memory) {
        Proposal memory p = proposalData[_client][_proposer][_actionId];
        return p.approval;
    }

    function setProposalData(address payable _client, address _proposer, bytes4 _actionId, bytes32 _hash, address _approvedBackup)
        external
        allowAuthorizedLogicContractsCallsOnly(_client)
    {
        Proposal storage p = proposalData[_client][_proposer][_actionId];
        if (p.hash > 0) {
            if (p.hash == _hash) {
                for (uint256 i = 0; i < p.approval.length; i++) {
                    require(p.approval[i] != _approvedBackup, "backup already exists");
                }
                p.approval.push(_approvedBackup);
            } else {
                p.hash = _hash;
                p.approval.length = 0;
            }
        } else {
            p.hash = _hash;
            p.approval.push(_approvedBackup);
        }
    }

    function clearProposalData(address payable _client, address _proposer, bytes4 _actionId) external allowAuthorizedLogicContractsCallsOnly(_client) {
        delete proposalData[_client][_proposer][_actionId];
    }


    // *************** init ********************** //
    function initAccount(Account _account, address[] calldata _keys, address[] calldata _backups)
        external
        allowAccountCallsOnly(_account)
    {
        require(getKeyData(address(_account), 0) == address(0), "AccountStorage: account already initialized!");
        require(_keys.length > 0, "empty keys array");

        operationKeyCount[address(_account)] = _keys.length - 1;

        for (uint256 index = 0; index < _keys.length; index++) {
            address _key = _keys[index];
            require(_key != address(0), "_key cannot be 0x0");
            KeyItem storage item = keyData[address(_account)][index];
            item.pubKey = _key;
            item.status = 0;
        }

        // avoid backup duplication if _backups.length > 1
        // normally won't check duplication, in most cases only one initial backup when initialization
        if (_backups.length > 1) {
            address[] memory bkps = _backups;
            for (uint256 i = 0; i < _backups.length; i++) {
                for (uint256 j = 0; j < i; j++) {
                    require(bkps[j] != _backups[i], "duplicate backup");
                }
            }
        }

        for (uint256 index = 0; index < _backups.length; index++) {
            address _backup = _backups[index];
            require(_backup != address(0), "backup cannot be 0x0");
            require(_backup != address(_account), "cannot be backup of oneself");

            backupData[address(_account)][index] = BackupAccount(_backup, now, uint256(-1));
        }
    }
}

/* The MIT License (MIT)

Copyright (c) 2016 Smart Contract Solutions, Inc.

Permission is hereby granted, free of charge, to any person obtaining
a copy of this software and associated documentation files (the
"Software"), to deal in the Software without restriction, including
without limitation the rights to use, copy, modify, merge, publish,
distribute, sublicense, and/or sell copies of the Software, and to
permit persons to whom the Software is furnished to do so, subject to
the following conditions:

The above copyright notice and this permission notice shall be included
in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */

/**
 * @title SafeMath
 * @dev Math operations with safety checks that throw on error
 */
library SafeMath {

    /**
    * @dev Multiplies two numbers, reverts on overflow.
    */
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
        // benefit is lost if 'b' is also tested.
        // See: https://github.com/OpenZeppelin/openzeppelin-solidity/pull/522
        if (a == 0) {
            return 0;
        }

        uint256 c = a * b;
        require(c / a == b);

        return c;
    }

    /**
    * @dev Integer division of two numbers truncating the quotient, reverts on division by zero.
    */
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b > 0); // Solidity only automatically asserts when dividing by 0
        uint256 c = a / b;
        // assert(a == b * c + a % b); // There is no case in which this doesn't hold

        return c;
    }

    /**
    * @dev Subtracts two numbers, reverts on overflow (i.e. if subtrahend is greater than minuend).
    */
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b <= a);
        uint256 c = a - b;

        return c;
    }

    /**
    * @dev Adds two numbers, reverts on overflow.
    */
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        require(c >= a);

        return c;
    }

    /**
    * @dev Divides two numbers and returns the remainder (unsigned integer modulo),
    * reverts when dividing by zero.
    */
    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b != 0);
        return a % b;
    }

    /**
    * @dev Returns ceil(a / b).
    */
    function ceil(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a / b;
        if(a % b == 0) {
            return c;
        }
        else {
            return c + 1;
        }
    }
}

contract BaseLogic {

    bytes constant internal SIGN_HASH_PREFIX = "\x19Ethereum Signed Message:\n32";

    mapping (address => uint256) keyNonce;
    AccountStorage public accountStorage;

    modifier allowSelfCallsOnly() {
        require (msg.sender == address(this), "only internal call is allowed");
        _;
    }

    modifier allowAccountCallsOnly(Account _account) {
        require(msg.sender == address(_account), "caller must be account");
        _;
    }

    event LogicInitialised(address wallet);

    // *************** Constructor ********************** //

    constructor(AccountStorage _accountStorage) public {
        accountStorage = _accountStorage;
    }

    // *************** Initialization ********************* //

    function initAccount(Account _account) external allowAccountCallsOnly(_account){
        emit LogicInitialised(address(_account));
    }

    // *************** Getter ********************** //

    function getKeyNonce(address _key) external view returns(uint256) {
        return keyNonce[_key];
    }

    // *************** Signature ********************** //

    function getSignHash(bytes memory _data, uint256 _nonce) internal view returns(bytes32) {
        // use EIP 191
        // 0x1900 + this logic address + data + nonce of signing key
        bytes32 msgHash = keccak256(abi.encodePacked(byte(0x19), byte(0), address(this), _data, _nonce));
        bytes32 prefixedHash = keccak256(abi.encodePacked(SIGN_HASH_PREFIX, msgHash));
        return prefixedHash;
    }

    function verifySig(address _signingKey, bytes memory _signature, bytes32 _signHash) internal pure {
        require(_signingKey != address(0), "invalid signing key");
        address recoveredAddr = recover(_signHash, _signature);
        require(recoveredAddr == _signingKey, "signature verification failed");
    }

    /**
     * @dev Returns the address that signed a hashed message (`hash`) with
     * `signature`. This address can then be used for verification purposes.
     *
     * The `ecrecover` EVM opcode allows for malleable (non-unique) signatures:
     * this function rejects them by requiring the `s` value to be in the lower
     * half order, and the `v` value to be either 27 or 28.
     *
     * NOTE: This call _does not revert_ if the signature is invalid, or
     * if the signer is otherwise unable to be retrieved. In those scenarios,
     * the zero address is returned.
     *
     * IMPORTANT: `hash` _must_ be the result of a hash operation for the
     * verification to be secure: it is possible to craft signatures that
     * recover to arbitrary addresses for non-hashed data. A safe way to ensure
     * this is by receiving a hash of the original message (which may otherwise)
     * be too long), and then calling {toEthSignedMessageHash} on it.
     */
    function recover(bytes32 hash, bytes memory signature) internal pure returns (address) {
        // Check the signature length
        if (signature.length != 65) {
            return (address(0));
        }

        // Divide the signature in r, s and v variables
        bytes32 r;
        bytes32 s;
        uint8 v;

        // ecrecover takes the signature parameters, and the only way to get them
        // currently is to use assembly.
        // solhint-disable-next-line no-inline-assembly
        assembly {
            r := mload(add(signature, 0x20))
            s := mload(add(signature, 0x40))
            v := byte(0, mload(add(signature, 0x60)))
        }

        // EIP-2 still allows signature malleability for ecrecover(). Remove this possibility and make the signature
        // unique. Appendix F in the Ethereum Yellow paper (https://ethereum.github.io/yellowpaper/paper.pdf), defines
        // the valid range for s in (281): 0 < s < secp256k1n ÷ 2 + 1, and for v in (282): v ∈ {27, 28}. Most
        // signatures from current libraries generate a unique signature with an s-value in the lower half order.
        //
        // If your library generates malleable signatures, such as s-values in the upper range, calculate a new s-value
        // with 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141 - s1 and flip v from 27 to 28 or
        // vice versa. If your library also generates signatures with 0/1 for v instead 27/28, add 27 to v to accept
        // these malleable signatures as well.
        if (uint256(s) > 0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0) {
            return address(0);
        }

        if (v != 27 && v != 28) {
            return address(0);
        }

        // If the signature is valid (and not malleable), return the signer address
        return ecrecover(hash, v, r, s);
    }

    /* get signer address from data
    * @dev Gets an address encoded as the first argument in transaction data
    * @param b The byte array that should have an address as first argument
    * @returns a The address retrieved from the array
    */
    function getSignerAddress(bytes memory _b) internal pure returns (address _a) {
        require(_b.length >= 36, "invalid bytes");
        // solium-disable-next-line security/no-inline-assembly
        assembly {
            let mask := 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF
            _a := and(mask, mload(add(_b, 36)))
            // b = {length:32}{method sig:4}{address:32}{...}
            // 36 is the offset of the first parameter of the data, if encoded properly.
            // 32 bytes for the length of the bytes array, and the first 4 bytes for the function signature.
            // 32 bytes is the length of the bytes array!!!!
        }
    }

    // get method id, first 4 bytes of data
    function getMethodId(bytes memory _b) internal pure returns (bytes4 _a) {
        require(_b.length >= 4, "invalid data");
        // solium-disable-next-line security/no-inline-assembly
        assembly {
            // 32 bytes is the length of the bytes array
            _a := mload(add(_b, 32))
        }
    }

    function checkKeyStatus(address _account, uint256 _index) internal {
        // check operation key status
        if (_index > 0) {
            require(accountStorage.getKeyStatus(_account, _index) != 1, "frozen key");
        }
    }

    // _nonce is timestamp in microsecond(1/1000000 second)
    function checkAndUpdateNonce(address _key, uint256 _nonce) internal {
        require(_nonce > keyNonce[_key], "nonce too small");
        require(SafeMath.div(_nonce, 1000000) <= now + 86400, "nonce too big"); // 86400=24*3600 seconds

        keyNonce[_key] = _nonce;
    }
}

contract DappLogic is BaseLogic {
    
    using RLPReader for RLPReader.RLPItem;
    using RLPReader for bytes;

    /*
    index 0: admin key
          1: asset(transfer)
          2: adding
          3: reserved(dapp)
          4: assist
     */
    uint constant internal DAPP_KEY_INDEX = 3;

    // *************** Events *************************** //

    event DappLogicInitialised(address indexed account);
    event DappLogicEntered(bytes data, uint256 indexed nonce);

    // *************** Constructor ********************** //
    constructor(AccountStorage _accountStorage)
        BaseLogic(_accountStorage)
        public
    {
    }

    // *************** Initialization ********************* //

    function initAccount(Account _account) external allowAccountCallsOnly(_account){
        emit DappLogicInitialised(address(_account));
    }

    // *************** action entry ********************* //

    function enter(bytes calldata _data, bytes calldata _signature, uint256 _nonce) external {
        address account = getSignerAddress(_data);
        checkKeyStatus(account, DAPP_KEY_INDEX);

        address dappKey = accountStorage.getKeyData(account, DAPP_KEY_INDEX);
        checkAndUpdateNonce(dappKey, _nonce);
        bytes32 signHash = getSignHash(_data, _nonce);
        verifySig(dappKey, _signature, signHash);

        // solium-disable-next-line security/no-low-level-calls
        (bool success,) = address(this).call(_data);
        require(success, "calling self failed");
        emit DappLogicEntered(_data, _nonce);
    }

    // *************** call Dapp ********************* //

    // called from 'enter'
    // call other contract from base account
    function callContract(address payable _account, address payable _target, uint256 _value, bytes calldata _methodData) external allowSelfCallsOnly {
        // Account(_account).invoke(_target, _value, _methodData);
        bool success;
        // solium-disable-next-line security/no-low-level-calls
        (success,) = _account.call(abi.encodeWithSignature("invoke(address,uint256,bytes)", _target, _value, _methodData));
        require(success, "calling invoke failed");
    }
    
    // called from 'enter'
    // call serveral other contracts at a time
    // rlp encode _methodData array into rlpBytes
    function callMultiContract(address payable _account, address[] calldata _targets, uint256[] calldata _values, bytes calldata _rlpBytes) external allowSelfCallsOnly {
        RLPReader.RLPItem[] memory ls = _rlpBytes.toRlpItem().toList();

        uint256 len = _targets.length;
        require(len == _values.length && len == ls.length, "length mismatch");
        for (uint256 i = 0; i < len; i++) {
            bool success;
            RLPReader.RLPItem memory item = ls[i];
            // solium-disable-next-line security/no-low-level-calls
            (success,) = _account.call(abi.encodeWithSignature("invoke(address,uint256,bytes)", _targets[i], _values[i], bytes(item.toBytes())));
            require(success, "calling invoke failed");
        }
    }

}

// Copyright (C) 2015, 2016, 2017 Dapphub

// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.

// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

pragma solidity ^0.4.18;

contract WETH9 {
    string public name     = "Wrapped Ether";
    string public symbol   = "WETH";
    uint8  public decimals = 18;

    event  Approval(address indexed src, address indexed guy, uint wad);
    event  Transfer(address indexed src, address indexed dst, uint wad);
    event  Deposit(address indexed dst, uint wad);
    event  Withdrawal(address indexed src, uint wad);

    mapping (address => uint)                       public  balanceOf;
    mapping (address => mapping (address => uint))  public  allowance;

    function() public payable {
        deposit();
    }
    function deposit() public payable {
        balanceOf[msg.sender] += msg.value;
        Deposit(msg.sender, msg.value);
    }
    function withdraw(uint wad) public {
        require(balanceOf[msg.sender] >= wad);
        balanceOf[msg.sender] -= wad;
        msg.sender.transfer(wad);
        Withdrawal(msg.sender, wad);
    }

    function totalSupply() public view returns (uint) {
        return this.balance;
    }

    function approve(address guy, uint wad) public returns (bool) {
        allowance[msg.sender][guy] = wad;
        Approval(msg.sender, guy, wad);
        return true;
    }

    function transfer(address dst, uint wad) public returns (bool) {
        return transferFrom(msg.sender, dst, wad);
    }

    function transferFrom(address src, address dst, uint wad)
        public
        returns (bool)
    {
        require(balanceOf[src] >= wad);

        if (src != msg.sender && allowance[src][msg.sender] != uint(-1)) {
            require(allowance[src][msg.sender] >= wad);
            allowance[src][msg.sender] -= wad;
        }

        balanceOf[src] -= wad;
        balanceOf[dst] += wad;

        Transfer(src, dst, wad);

        return true;
    }
}


/*
                    GNU GENERAL PUBLIC LICENSE
                       Version 3, 29 June 2007

 Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
 Everyone is permitted to copy and distribute verbatim copies
 of this license document, but changing it is not allowed.

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*/

/// matching_market.sol

//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <https://www.gnu.org/licenses/>.

pragma solidity ^0.5.12;

contract DSAuthority {
    function canCall(
        address src, address dst, bytes4 sig
    ) public view returns (bool);
}

contract DSAuthEvents {
    event LogSetAuthority (address indexed authority);
    event LogSetOwner     (address indexed owner);
}

contract DSAuth is DSAuthEvents {
    DSAuthority  public  authority;
    address      public  owner;

    constructor() public {
        owner = msg.sender;
        emit LogSetOwner(msg.sender);
    }

    function setOwner(address owner_)
        public
        auth
    {
        owner = owner_;
        emit LogSetOwner(owner);
    }

    function setAuthority(DSAuthority authority_)
        public
        auth
    {
        authority = authority_;
        emit LogSetAuthority(address(authority));
    }

    modifier auth {
        require(isAuthorized(msg.sender, msg.sig), "ds-auth-unauthorized");
        _;
    }

    function isAuthorized(address src, bytes4 sig) internal view returns (bool) {
        if (src == address(this)) {
            return true;
        } else if (src == owner) {
            return true;
        } else if (authority == DSAuthority(0)) {
            return false;
        } else {
            return authority.canCall(src, address(this), sig);
        }
    }
}

contract DSMath {
    function add(uint x, uint y) internal pure returns (uint z) {
        require((z = x + y) >= x, "ds-math-add-overflow");
    }
    function sub(uint x, uint y) internal pure returns (uint z) {
        require((z = x - y) <= x, "ds-math-sub-underflow");
    }
    function mul(uint x, uint y) internal pure returns (uint z) {
        require(y == 0 || (z = x * y) / y == x, "ds-math-mul-overflow");
    }

    function min(uint x, uint y) internal pure returns (uint z) {
        return x <= y ? x : y;
    }
    function max(uint x, uint y) internal pure returns (uint z) {
        return x >= y ? x : y;
    }
    function imin(int x, int y) internal pure returns (int z) {
        return x <= y ? x : y;
    }
    function imax(int x, int y) internal pure returns (int z) {
        return x >= y ? x : y;
    }

    uint constant WAD = 10 ** 18;
    uint constant RAY = 10 ** 27;

    function wmul(uint x, uint y) internal pure returns (uint z) {
        z = add(mul(x, y), WAD / 2) / WAD;
    }
    function rmul(uint x, uint y) internal pure returns (uint z) {
        z = add(mul(x, y), RAY / 2) / RAY;
    }
    function wdiv(uint x, uint y) internal pure returns (uint z) {
        z = add(mul(x, WAD), y / 2) / y;
    }
    function rdiv(uint x, uint y) internal pure returns (uint z) {
        z = add(mul(x, RAY), y / 2) / y;
    }

    // This famous algorithm is called "exponentiation by squaring"
    // and calculates x^n with x as fixed-point and n as regular unsigned.
    //
    // It's O(log n), instead of O(n) for naive repeated multiplication.
    //
    // These facts are why it works:
    //
    //  If n is even, then x^n = (x^2)^(n/2).
    //  If n is odd,  then x^n = x * x^(n-1),
    //   and applying the equation for even x gives
    //    x^n = x * (x^2)^((n-1) / 2).
    //
    //  Also, EVM division is flooring and
    //    floor[(n-1) / 2] = floor[n / 2].
    //
    function rpow(uint x, uint n) internal pure returns (uint z) {
        z = n % 2 != 0 ? x : RAY;

        for (n /= 2; n != 0; n /= 2) {
            x = rmul(x, x);

            if (n % 2 != 0) {
                z = rmul(z, x);
            }
        }
    }
}

contract ERC20Events {
    event Approval(address indexed src, address indexed guy, uint wad);
    event Transfer(address indexed src, address indexed dst, uint wad);
}

contract ERC20 is ERC20Events {
    function totalSupply() public view returns (uint);
    function balanceOf(address guy) public view returns (uint);
    function allowance(address src, address guy) public view returns (uint);

    function approve(address guy, uint wad) public returns (bool);
    function transfer(address dst, uint wad) public returns (bool);
    function transferFrom(
        address src, address dst, uint wad
    ) public returns (bool);
}

contract EventfulMarket {
    event LogItemUpdate(uint id);
    event LogTrade(uint pay_amt, address indexed pay_gem,
                   uint buy_amt, address indexed buy_gem);

    event LogMake(
        bytes32  indexed  id,
        bytes32  indexed  pair,
        address  indexed  maker,
        ERC20             pay_gem,
        ERC20             buy_gem,
        uint128           pay_amt,
        uint128           buy_amt,
        uint64            timestamp
    );

    event LogBump(
        bytes32  indexed  id,
        bytes32  indexed  pair,
        address  indexed  maker,
        ERC20             pay_gem,
        ERC20             buy_gem,
        uint128           pay_amt,
        uint128           buy_amt,
        uint64            timestamp
    );

    event LogTake(
        bytes32           id,
        bytes32  indexed  pair,
        address  indexed  maker,
        ERC20             pay_gem,
        ERC20             buy_gem,
        address  indexed  taker,
        uint128           take_amt,
        uint128           give_amt,
        uint64            timestamp
    );

    event LogKill(
        bytes32  indexed  id,
        bytes32  indexed  pair,
        address  indexed  maker,
        ERC20             pay_gem,
        ERC20             buy_gem,
        uint128           pay_amt,
        uint128           buy_amt,
        uint64            timestamp
    );
}

contract SimpleMarket is EventfulMarket, DSMath {

    uint public last_offer_id;

    mapping (uint => OfferInfo) public offers;

    bool locked;

    struct OfferInfo {
        uint     pay_amt;
        ERC20    pay_gem;
        uint     buy_amt;
        ERC20    buy_gem;
        address  owner;
        uint64   timestamp;
    }

    modifier can_buy(uint id) {
        require(isActive(id));
        _;
    }

    modifier can_cancel(uint id) {
        require(isActive(id));
        require(getOwner(id) == msg.sender);
        _;
    }

    modifier can_offer {
        _;
    }

    modifier synchronized {
        require(!locked);
        locked = true;
        _;
        locked = false;
    }

    function isActive(uint id) public view returns (bool active) {
        return offers[id].timestamp > 0;
    }

    function getOwner(uint id) public view returns (address owner) {
        return offers[id].owner;
    }

    function getOffer(uint id) public view returns (uint, ERC20, uint, ERC20) {
      OfferInfo memory offer = offers[id];
      return (offer.pay_amt, offer.pay_gem,
              offer.buy_amt, offer.buy_gem);
    }

    // ---- Public entrypoints ---- //

    function bump(bytes32 id_)
        public
        can_buy(uint256(id_))
    {
        uint256 id = uint256(id_);
        emit LogBump(
            id_,
            keccak256(abi.encodePacked(offers[id].pay_gem, offers[id].buy_gem)),
            offers[id].owner,
            offers[id].pay_gem,
            offers[id].buy_gem,
            uint128(offers[id].pay_amt),
            uint128(offers[id].buy_amt),
            offers[id].timestamp
        );
    }

    // Accept given `quantity` of an offer. Transfers funds from caller to
    // offer maker, and from market to caller.
    function buy(uint id, uint quantity)
        public
        can_buy(id)
        synchronized
        returns (bool)
    {
        OfferInfo memory offer = offers[id];
        uint spend = mul(quantity, offer.buy_amt) / offer.pay_amt;

        require(uint128(spend) == spend);
        require(uint128(quantity) == quantity);

        // For backwards semantic compatibility.
        if (quantity == 0 || spend == 0 ||
            quantity > offer.pay_amt || spend > offer.buy_amt)
        {
            return false;
        }

        offers[id].pay_amt = sub(offer.pay_amt, quantity);
        offers[id].buy_amt = sub(offer.buy_amt, spend);
        require( offer.buy_gem.transferFrom(msg.sender, offer.owner, spend) );
        require( offer.pay_gem.transfer(msg.sender, quantity) );

        emit LogItemUpdate(id);
        emit LogTake(
            bytes32(id),
            keccak256(abi.encodePacked(offer.pay_gem, offer.buy_gem)),
            offer.owner,
            offer.pay_gem,
            offer.buy_gem,
            msg.sender,
            uint128(quantity),
            uint128(spend),
            uint64(now)
        );
        emit LogTrade(quantity, address(offer.pay_gem), spend, address(offer.buy_gem));

        if (offers[id].pay_amt == 0) {
          delete offers[id];
        }

        return true;
    }

    // Cancel an offer. Refunds offer maker.
    function cancel(uint id)
        public
        can_cancel(id)
        synchronized
        returns (bool success)
    {
        // read-only offer. Modify an offer by directly accessing offers[id]
        OfferInfo memory offer = offers[id];
        delete offers[id];

        require( offer.pay_gem.transfer(offer.owner, offer.pay_amt) );

        emit LogItemUpdate(id);
        emit LogKill(
            bytes32(id),
            keccak256(abi.encodePacked(offer.pay_gem, offer.buy_gem)),
            offer.owner,
            offer.pay_gem,
            offer.buy_gem,
            uint128(offer.pay_amt),
            uint128(offer.buy_amt),
            uint64(now)
        );

        success = true;
    }

    function kill(bytes32 id)
        public
    {
        require(cancel(uint256(id)));
    }

    function make(
        ERC20    pay_gem,
        ERC20    buy_gem,
        uint128  pay_amt,
        uint128  buy_amt
    )
        public
        returns (bytes32 id)
    {
        return bytes32(offer(pay_amt, pay_gem, buy_amt, buy_gem));
    }

    // Make a new offer. Takes funds from the caller into market escrow.
    function offer(uint pay_amt, ERC20 pay_gem, uint buy_amt, ERC20 buy_gem)
        public
        can_offer
        synchronized
        returns (uint id)
    {
        require(uint128(pay_amt) == pay_amt);
        require(uint128(buy_amt) == buy_amt);
        require(pay_amt > 0);
        require(pay_gem != ERC20(0x0));
        require(buy_amt > 0);
        require(buy_gem != ERC20(0x0));
        require(pay_gem != buy_gem);

        OfferInfo memory info;
        info.pay_amt = pay_amt;
        info.pay_gem = pay_gem;
        info.buy_amt = buy_amt;
        info.buy_gem = buy_gem;
        info.owner = msg.sender;
        info.timestamp = uint64(now);
        id = _next_id();
        offers[id] = info;

        require( pay_gem.transferFrom(msg.sender, address(this), pay_amt) );

        emit LogItemUpdate(id);
        emit LogMake(
            bytes32(id),
            keccak256(abi.encodePacked(pay_gem, buy_gem)),
            msg.sender,
            pay_gem,
            buy_gem,
            uint128(pay_amt),
            uint128(buy_amt),
            uint64(now)
        );
    }

    function take(bytes32 id, uint128 maxTakeAmount)
        public
    {
        require(buy(uint256(id), maxTakeAmount));
    }

    function _next_id()
        internal
        returns (uint)
    {
        last_offer_id++; return last_offer_id;
    }
}

// Simple Market with a market lifetime. When the close_time has been reached,
// offers can only be cancelled (offer and buy will throw).

contract ExpiringMarket is DSAuth, SimpleMarket {
    uint64 public close_time;
    bool public stopped;

    // after close_time has been reached, no new offers are allowed
    modifier can_offer {
        require(!isClosed());
        _;
    }

    // after close, no new buys are allowed
    modifier can_buy(uint id) {
        require(isActive(id));
        require(!isClosed());
        _;
    }

    // after close, anyone can cancel an offer
    modifier can_cancel(uint id) {
        require(isActive(id));
        require((msg.sender == getOwner(id)) || isClosed());
        _;
    }

    constructor(uint64 _close_time)
        public
    {
        close_time = _close_time;
    }

    function isClosed() public view returns (bool closed) {
        return stopped || getTime() > close_time;
    }

    function getTime() public view returns (uint64) {
        return uint64(now);
    }

    function stop() public auth {
        stopped = true;
    }
}

contract DSNote {
    event LogNote(
        bytes4   indexed  sig,
        address  indexed  guy,
        bytes32  indexed  foo,
        bytes32  indexed  bar,
        uint256           wad,
        bytes             fax
    ) anonymous;

    modifier note {
        bytes32 foo;
        bytes32 bar;
        uint256 wad;

        assembly {
            foo := calldataload(4)
            bar := calldataload(36)
            wad := callvalue
        }

        emit LogNote(msg.sig, msg.sender, foo, bar, wad, msg.data);

        _;
    }
}

contract MatchingEvents {
    event LogBuyEnabled(bool isEnabled);
    event LogMinSell(address pay_gem, uint min_amount);
    event LogMatchingEnabled(bool isEnabled);
    event LogUnsortedOffer(uint id);
    event LogSortedOffer(uint id);
    event LogInsert(address keeper, uint id);
    event LogDelete(address keeper, uint id);
}

contract MatchingMarket is MatchingEvents, ExpiringMarket, DSNote {
    bool public buyEnabled = true;      //buy enabled
    bool public matchingEnabled = true; //true: enable matching,
                                         //false: revert to expiring market
    struct sortInfo {
        uint next;  //points to id of next higher offer
        uint prev;  //points to id of previous lower offer
        uint delb;  //the blocknumber where this entry was marked for delete
    }
    mapping(uint => sortInfo) public _rank;                     //doubly linked lists of sorted offer ids
    mapping(address => mapping(address => uint)) public _best;  //id of the highest offer for a token pair
    mapping(address => mapping(address => uint)) public _span;  //number of offers stored for token pair in sorted orderbook
    mapping(address => uint) public _dust;                      //minimum sell amount for a token to avoid dust offers
    mapping(uint => uint) public _near;         //next unsorted offer id
    uint _head;                                 //first unsorted offer id
    uint public dustId;                         // id of the latest offer marked as dust


    constructor(uint64 close_time) ExpiringMarket(close_time) public {
    }

    // After close, anyone can cancel an offer
    modifier can_cancel(uint id) {
        require(isActive(id), "Offer was deleted or taken, or never existed.");
        require(
            isClosed() || msg.sender == getOwner(id) || id == dustId,
            "Offer can not be cancelled because user is not owner, and market is open, and offer sells required amount of tokens."
        );
        _;
    }

    // ---- Public entrypoints ---- //

    function make(
        ERC20    pay_gem,
        ERC20    buy_gem,
        uint128  pay_amt,
        uint128  buy_amt
    )
        public
        returns (bytes32)
    {
        return bytes32(offer(pay_amt, pay_gem, buy_amt, buy_gem));
    }

    function take(bytes32 id, uint128 maxTakeAmount) public {
        require(buy(uint256(id), maxTakeAmount));
    }

    function kill(bytes32 id) public {
        require(cancel(uint256(id)));
    }

    // Make a new offer. Takes funds from the caller into market escrow.
    //
    // If matching is enabled:
    //     * creates new offer without putting it in
    //       the sorted list.
    //     * available to authorized contracts only!
    //     * keepers should call insert(id,pos)
    //       to put offer in the sorted list.
    //
    // If matching is disabled:
    //     * calls expiring market's offer().
    //     * available to everyone without authorization.
    //     * no sorting is done.
    //
    function offer(
        uint pay_amt,    //maker (ask) sell how much
        ERC20 pay_gem,   //maker (ask) sell which token
        uint buy_amt,    //taker (ask) buy how much
        ERC20 buy_gem    //taker (ask) buy which token
    )
        public
        returns (uint)
    {
        require(!locked, "Reentrancy attempt");
        function (uint256,ERC20,uint256,ERC20) returns (uint256) fn = matchingEnabled ? _offeru : super.offer;
        return fn(pay_amt, pay_gem, buy_amt, buy_gem);
    }

    // Make a new offer. Takes funds from the caller into market escrow.
    function offer(
        uint pay_amt,    //maker (ask) sell how much
        ERC20 pay_gem,   //maker (ask) sell which token
        uint buy_amt,    //maker (ask) buy how much
        ERC20 buy_gem,   //maker (ask) buy which token
        uint pos         //position to insert offer, 0 should be used if unknown
    )
        public
        can_offer
        returns (uint)
    {
        return offer(pay_amt, pay_gem, buy_amt, buy_gem, pos, true);
    }

    function offer(
        uint pay_amt,    //maker (ask) sell how much
        ERC20 pay_gem,   //maker (ask) sell which token
        uint buy_amt,    //maker (ask) buy how much
        ERC20 buy_gem,   //maker (ask) buy which token
        uint pos,        //position to insert offer, 0 should be used if unknown
        bool rounding    //match "close enough" orders?
    )
        public
        can_offer
        returns (uint)
    {
        require(!locked, "Reentrancy attempt");
        require(_dust[address(pay_gem)] <= pay_amt);

        if (matchingEnabled) {
          return _matcho(pay_amt, pay_gem, buy_amt, buy_gem, pos, rounding);
        }
        return super.offer(pay_amt, pay_gem, buy_amt, buy_gem);
    }

    //Transfers funds from caller to offer maker, and from market to caller.
    function buy(uint id, uint amount)
        public
        can_buy(id)
        returns (bool)
    {
        require(!locked, "Reentrancy attempt");
        function (uint256,uint256) returns (bool) fn = matchingEnabled ? _buys : super.buy;
        return fn(id, amount);
    }

    // Cancel an offer. Refunds offer maker.
    function cancel(uint id)
        public
        can_cancel(id)
        returns (bool success)
    {
        require(!locked, "Reentrancy attempt");
        if (matchingEnabled) {
            if (isOfferSorted(id)) {
                require(_unsort(id));
            } else {
                require(_hide(id));
            }
        }
        return super.cancel(id);    //delete the offer.
    }

    //insert offer into the sorted list
    //keepers need to use this function
    function insert(
        uint id,   //maker (ask) id
        uint pos   //position to insert into
    )
        public
        returns (bool)
    {
        require(!locked, "Reentrancy attempt");
        require(!isOfferSorted(id));    //make sure offers[id] is not yet sorted
        require(isActive(id));          //make sure offers[id] is active

        _hide(id);                      //remove offer from unsorted offers list
        _sort(id, pos);                 //put offer into the sorted offers list
        emit LogInsert(msg.sender, id);
        return true;
    }

    //deletes _rank [id]
    //  Function should be called by keepers.
    function del_rank(uint id)
        public
        returns (bool)
    {
        require(!locked, "Reentrancy attempt");
        require(!isActive(id) && _rank[id].delb != 0 && _rank[id].delb < block.number - 10);
        delete _rank[id];
        emit LogDelete(msg.sender, id);
        return true;
    }

    //set the minimum sell amount for a token
    //    Function is used to avoid "dust offers" that have
    //    very small amount of tokens to sell, and it would
    //    cost more gas to accept the offer, than the value
    //    of tokens received.
    function setMinSell(
        ERC20 pay_gem,     //token to assign minimum sell amount to
        uint dust          //maker (ask) minimum sell amount
    )
        public
        auth
        note
        returns (bool)
    {
        _dust[address(pay_gem)] = dust;
        emit LogMinSell(address(pay_gem), dust);
        return true;
    }

    //returns the minimum sell amount for an offer
    function getMinSell(
        ERC20 pay_gem      //token for which minimum sell amount is queried
    )
        public
        view
        returns (uint)
    {
        return _dust[address(pay_gem)];
    }

    //set buy functionality enabled/disabled
    function setBuyEnabled(bool buyEnabled_) public auth returns (bool) {
        buyEnabled = buyEnabled_;
        emit LogBuyEnabled(buyEnabled);
        return true;
    }

    //set matching enabled/disabled
    //    If matchingEnabled true(default), then inserted offers are matched.
    //    Except the ones inserted by contracts, because those end up
    //    in the unsorted list of offers, that must be later sorted by
    //    keepers using insert().
    //    If matchingEnabled is false then MatchingMarket is reverted to ExpiringMarket,
    //    and matching is not done, and sorted lists are disabled.
    function setMatchingEnabled(bool matchingEnabled_) public auth returns (bool) {
        matchingEnabled = matchingEnabled_;
        emit LogMatchingEnabled(matchingEnabled);
        return true;
    }

    //return the best offer for a token pair
    //      the best offer is the lowest one if it's an ask,
    //      and highest one if it's a bid offer
    function getBestOffer(ERC20 sell_gem, ERC20 buy_gem) public view returns(uint) {
        return _best[address(sell_gem)][address(buy_gem)];
    }

    //return the next worse offer in the sorted list
    //      the worse offer is the higher one if its an ask,
    //      a lower one if its a bid offer,
    //      and in both cases the newer one if they're equal.
    function getWorseOffer(uint id) public view returns(uint) {
        return _rank[id].prev;
    }

    //return the next better offer in the sorted list
    //      the better offer is in the lower priced one if its an ask,
    //      the next higher priced one if its a bid offer
    //      and in both cases the older one if they're equal.
    function getBetterOffer(uint id) public view returns(uint) {

        return _rank[id].next;
    }

    //return the amount of better offers for a token pair
    function getOfferCount(ERC20 sell_gem, ERC20 buy_gem) public view returns(uint) {
        return _span[address(sell_gem)][address(buy_gem)];
    }

    //get the first unsorted offer that was inserted by a contract
    //      Contracts can't calculate the insertion position of their offer because it is not an O(1) operation.
    //      Their offers get put in the unsorted list of offers.
    //      Keepers can calculate the insertion position offchain and pass it to the insert() function to insert
    //      the unsorted offer into the sorted list. Unsorted offers will not be matched, but can be bought with buy().
    function getFirstUnsortedOffer() public view returns(uint) {
        return _head;
    }

    //get the next unsorted offer
    //      Can be used to cycle through all the unsorted offers.
    function getNextUnsortedOffer(uint id) public view returns(uint) {
        return _near[id];
    }

    function isOfferSorted(uint id) public view returns(bool) {
        return _rank[id].next != 0
               || _rank[id].prev != 0
               || _best[address(offers[id].pay_gem)][address(offers[id].buy_gem)] == id;
    }

    function sellAllAmount(ERC20 pay_gem, uint pay_amt, ERC20 buy_gem, uint min_fill_amount)
        public
        returns (uint fill_amt)
    {
        require(!locked, "Reentrancy attempt");
        uint offerId;
        while (pay_amt > 0) {                           //while there is amount to sell
            offerId = getBestOffer(buy_gem, pay_gem);   //Get the best offer for the token pair
            require(offerId != 0);                      //Fails if there are not more offers

            // There is a chance that pay_amt is smaller than 1 wei of the other token
            if (pay_amt * 1 ether < wdiv(offers[offerId].buy_amt, offers[offerId].pay_amt)) {
                break;                                  //We consider that all amount is sold
            }
            if (pay_amt >= offers[offerId].buy_amt) {                       //If amount to sell is higher or equal than current offer amount to buy
                fill_amt = add(fill_amt, offers[offerId].pay_amt);          //Add amount bought to acumulator
                pay_amt = sub(pay_amt, offers[offerId].buy_amt);            //Decrease amount to sell
                take(bytes32(offerId), uint128(offers[offerId].pay_amt));   //We take the whole offer
            } else { // if lower
                uint256 baux = rmul(pay_amt * 10 ** 9, rdiv(offers[offerId].pay_amt, offers[offerId].buy_amt)) / 10 ** 9;
                fill_amt = add(fill_amt, baux);         //Add amount bought to acumulator
                take(bytes32(offerId), uint128(baux));  //We take the portion of the offer that we need
                pay_amt = 0;                            //All amount is sold
            }
        }
        require(fill_amt >= min_fill_amount);
    }

    function buyAllAmount(ERC20 buy_gem, uint buy_amt, ERC20 pay_gem, uint max_fill_amount)
        public
        returns (uint fill_amt)
    {
        require(!locked, "Reentrancy attempt");
        uint offerId;
        while (buy_amt > 0) {                           //Meanwhile there is amount to buy
            offerId = getBestOffer(buy_gem, pay_gem);   //Get the best offer for the token pair
            require(offerId != 0);

            // There is a chance that buy_amt is smaller than 1 wei of the other token
            if (buy_amt * 1 ether < wdiv(offers[offerId].pay_amt, offers[offerId].buy_amt)) {
                break;                                  //We consider that all amount is sold
            }
            if (buy_amt >= offers[offerId].pay_amt) {                       //If amount to buy is higher or equal than current offer amount to sell
                fill_amt = add(fill_amt, offers[offerId].buy_amt);          //Add amount sold to acumulator
                buy_amt = sub(buy_amt, offers[offerId].pay_amt);            //Decrease amount to buy
                take(bytes32(offerId), uint128(offers[offerId].pay_amt));   //We take the whole offer
            } else {                                                        //if lower
                fill_amt = add(fill_amt, rmul(buy_amt * 10 ** 9, rdiv(offers[offerId].buy_amt, offers[offerId].pay_amt)) / 10 ** 9); //Add amount sold to acumulator
                take(bytes32(offerId), uint128(buy_amt));                   //We take the portion of the offer that we need
                buy_amt = 0;                                                //All amount is bought
            }
        }
        require(fill_amt <= max_fill_amount);
    }

    function getBuyAmount(ERC20 buy_gem, ERC20 pay_gem, uint pay_amt) public view returns (uint fill_amt) {
        uint256 offerId = getBestOffer(buy_gem, pay_gem);           //Get best offer for the token pair
        while (pay_amt > offers[offerId].buy_amt) {
            fill_amt = add(fill_amt, offers[offerId].pay_amt);  //Add amount to buy accumulator
            pay_amt = sub(pay_amt, offers[offerId].buy_amt);    //Decrease amount to pay
            if (pay_amt > 0) {                                  //If we still need more offers
                offerId = getWorseOffer(offerId);               //We look for the next best offer
                require(offerId != 0);                          //Fails if there are not enough offers to complete
            }
        }
        fill_amt = add(fill_amt, rmul(pay_amt * 10 ** 9, rdiv(offers[offerId].pay_amt, offers[offerId].buy_amt)) / 10 ** 9); //Add proportional amount of last offer to buy accumulator
    }

    function getPayAmount(ERC20 pay_gem, ERC20 buy_gem, uint buy_amt) public view returns (uint fill_amt) {
        uint256 offerId = getBestOffer(buy_gem, pay_gem);           //Get best offer for the token pair
        while (buy_amt > offers[offerId].pay_amt) {
            fill_amt = add(fill_amt, offers[offerId].buy_amt);  //Add amount to pay accumulator
            buy_amt = sub(buy_amt, offers[offerId].pay_amt);    //Decrease amount to buy
            if (buy_amt > 0) {                                  //If we still need more offers
                offerId = getWorseOffer(offerId);               //We look for the next best offer
                require(offerId != 0);                          //Fails if there are not enough offers to complete
            }
        }
        fill_amt = add(fill_amt, rmul(buy_amt * 10 ** 9, rdiv(offers[offerId].buy_amt, offers[offerId].pay_amt)) / 10 ** 9); //Add proportional amount of last offer to pay accumulator
    }

    // ---- Internal Functions ---- //

    function _buys(uint id, uint amount)
        internal
        returns (bool)
    {
        require(buyEnabled);
        if (amount == offers[id].pay_amt) {
            if (isOfferSorted(id)) {
                //offers[id] must be removed from sorted list because all of it is bought
                _unsort(id);
            }else{
                _hide(id);
            }
        }
        require(super.buy(id, amount));
        // If offer has become dust during buy, we cancel it
        if (isActive(id) && offers[id].pay_amt < _dust[address(offers[id].pay_gem)]) {
            dustId = id; //enable current msg.sender to call cancel(id)
            cancel(id);
        }
        return true;
    }

    //find the id of the next higher offer after offers[id]
    function _find(uint id)
        internal
        view
        returns (uint)
    {
        require( id > 0 );

        address buy_gem = address(offers[id].buy_gem);
        address pay_gem = address(offers[id].pay_gem);
        uint top = _best[pay_gem][buy_gem];
        uint old_top = 0;

        // Find the larger-than-id order whose successor is less-than-id.
        while (top != 0 && _isPricedLtOrEq(id, top)) {
            old_top = top;
            top = _rank[top].prev;
        }
        return old_top;
    }

    //find the id of the next higher offer after offers[id]
    function _findpos(uint id, uint pos)
        internal
        view
        returns (uint)
    {
        require(id > 0);

        // Look for an active order.
        while (pos != 0 && !isActive(pos)) {
            pos = _rank[pos].prev;
        }

        if (pos == 0) {
            //if we got to the end of list without a single active offer
            return _find(id);

        } else {
            // if we did find a nearby active offer
            // Walk the order book down from there...
            if(_isPricedLtOrEq(id, pos)) {
                uint old_pos;

                // Guaranteed to run at least once because of
                // the prior if statements.
                while (pos != 0 && _isPricedLtOrEq(id, pos)) {
                    old_pos = pos;
                    pos = _rank[pos].prev;
                }
                return old_pos;

            // ...or walk it up.
            } else {
                while (pos != 0 && !_isPricedLtOrEq(id, pos)) {
                    pos = _rank[pos].next;
                }
                return pos;
            }
        }
    }

    //return true if offers[low] priced less than or equal to offers[high]
    function _isPricedLtOrEq(
        uint low,   //lower priced offer's id
        uint high   //higher priced offer's id
    )
        internal
        view
        returns (bool)
    {
        return mul(offers[low].buy_amt, offers[high].pay_amt)
          >= mul(offers[high].buy_amt, offers[low].pay_amt);
    }

    //these variables are global only because of solidity local variable limit

    //match offers with taker offer, and execute token transactions
    function _matcho(
        uint t_pay_amt,    //taker sell how much
        ERC20 t_pay_gem,   //taker sell which token
        uint t_buy_amt,    //taker buy how much
        ERC20 t_buy_gem,   //taker buy which token
        uint pos,          //position id
        bool rounding      //match "close enough" orders?
    )
        internal
        returns (uint id)
    {
        uint best_maker_id;    //highest maker id
        uint t_buy_amt_old;    //taker buy how much saved
        uint m_buy_amt;        //maker offer wants to buy this much token
        uint m_pay_amt;        //maker offer wants to sell this much token

        // there is at least one offer stored for token pair
        while (_best[address(t_buy_gem)][address(t_pay_gem)] > 0) {
            best_maker_id = _best[address(t_buy_gem)][address(t_pay_gem)];
            m_buy_amt = offers[best_maker_id].buy_amt;
            m_pay_amt = offers[best_maker_id].pay_amt;

            // Ugly hack to work around rounding errors. Based on the idea that
            // the furthest the amounts can stray from their "true" values is 1.
            // Ergo the worst case has t_pay_amt and m_pay_amt at +1 away from
            // their "correct" values and m_buy_amt and t_buy_amt at -1.
            // Since (c - 1) * (d - 1) > (a + 1) * (b + 1) is equivalent to
            // c * d > a * b + a + b + c + d, we write...
            if (mul(m_buy_amt, t_buy_amt) > mul(t_pay_amt, m_pay_amt) +
                (rounding ? m_buy_amt + t_buy_amt + t_pay_amt + m_pay_amt : 0))
            {
                break;
            }
            // ^ The `rounding` parameter is a compromise borne of a couple days
            // of discussion.
            buy(best_maker_id, min(m_pay_amt, t_buy_amt));
            t_buy_amt_old = t_buy_amt;
            t_buy_amt = sub(t_buy_amt, min(m_pay_amt, t_buy_amt));
            t_pay_amt = mul(t_buy_amt, t_pay_amt) / t_buy_amt_old;

            if (t_pay_amt == 0 || t_buy_amt == 0) {
                break;
            }
        }

        if (t_buy_amt > 0 && t_pay_amt > 0 && t_pay_amt >= _dust[address(t_pay_gem)]) {
            //new offer should be created
            id = super.offer(t_pay_amt, t_pay_gem, t_buy_amt, t_buy_gem);
            //insert offer into the sorted list
            _sort(id, pos);
        }
    }

    // Make a new offer without putting it in the sorted list.
    // Takes funds from the caller into market escrow.
    // ****Available to authorized contracts only!**********
    // Keepers should call insert(id,pos) to put offer in the sorted list.
    function _offeru(
        uint pay_amt,      //maker (ask) sell how much
        ERC20 pay_gem,     //maker (ask) sell which token
        uint buy_amt,      //maker (ask) buy how much
        ERC20 buy_gem      //maker (ask) buy which token
    )
        internal
        returns (uint id)
    {
        require(_dust[address(pay_gem)] <= pay_amt);
        id = super.offer(pay_amt, pay_gem, buy_amt, buy_gem);
        _near[id] = _head;
        _head = id;
        emit LogUnsortedOffer(id);
    }

    //put offer into the sorted list
    function _sort(
        uint id,    //maker (ask) id
        uint pos    //position to insert into
    )
        internal
    {
        require(isActive(id));

        ERC20 buy_gem = offers[id].buy_gem;
        ERC20 pay_gem = offers[id].pay_gem;
        uint prev_id;                                      //maker (ask) id

        pos = pos == 0 || offers[pos].pay_gem != pay_gem || offers[pos].buy_gem != buy_gem || !isOfferSorted(pos)
        ?
            _find(id)
        :
            _findpos(id, pos);

        if (pos != 0) {                                    //offers[id] is not the highest offer
            //requirement below is satisfied by statements above
            //require(_isPricedLtOrEq(id, pos));
            prev_id = _rank[pos].prev;
            _rank[pos].prev = id;
            _rank[id].next = pos;
        } else {                                           //offers[id] is the highest offer
            prev_id = _best[address(pay_gem)][address(buy_gem)];
            _best[address(pay_gem)][address(buy_gem)] = id;
        }

        if (prev_id != 0) {                               //if lower offer does exist
            //requirement below is satisfied by statements above
            //require(!_isPricedLtOrEq(id, prev_id));
            _rank[prev_id].next = id;
            _rank[id].prev = prev_id;
        }

        _span[address(pay_gem)][address(buy_gem)]++;
        emit LogSortedOffer(id);
    }

    // Remove offer from the sorted list (does not cancel offer)
    function _unsort(
        uint id    //id of maker (ask) offer to remove from sorted list
    )
        internal
        returns (bool)
    {
        address buy_gem = address(offers[id].buy_gem);
        address pay_gem = address(offers[id].pay_gem);
        require(_span[pay_gem][buy_gem] > 0);

        require(_rank[id].delb == 0 &&                    //assert id is in the sorted list
                 isOfferSorted(id));

        if (id != _best[pay_gem][buy_gem]) {              // offers[id] is not the highest offer
            require(_rank[_rank[id].next].prev == id);
            _rank[_rank[id].next].prev = _rank[id].prev;
        } else {                                          //offers[id] is the highest offer
            _best[pay_gem][buy_gem] = _rank[id].prev;
        }

        if (_rank[id].prev != 0) {                        //offers[id] is not the lowest offer
            require(_rank[_rank[id].prev].next == id);
            _rank[_rank[id].prev].next = _rank[id].next;
        }

        _span[pay_gem][buy_gem]--;
        _rank[id].delb = block.number;                    //mark _rank[id] for deletion
        return true;
    }

    //Hide offer from the unsorted order book (does not cancel offer)
    function _hide(
        uint id     //id of maker offer to remove from unsorted list
    )
        internal
        returns (bool)
    {
        uint uid = _head;               //id of an offer in unsorted offers list
        uint pre = uid;                 //id of previous offer in unsorted offers list

        require(!isOfferSorted(id));    //make sure offer id is not in sorted offers list

        if (_head == id) {              //check if offer is first offer in unsorted offers list
            _head = _near[id];          //set head to new first unsorted offer
            _near[id] = 0;              //delete order from unsorted order list
            return true;
        }
        while (uid > 0 && uid != id) {  //find offer in unsorted order list
            pre = uid;
            uid = _near[uid];
        }
        if (uid != id) {                //did not find offer id in unsorted offers list
            return false;
        }
        _near[pre] = _near[id];         //set previous unsorted offer to point to offer after offer id
        _near[id] = 0;                  //delete order from unsorted order list
        return true;
    }
}

// hevm: flattened sources of /nix/store/8xb41r4qd0cjb63wcrxf1qmfg88p0961-dss-6fd7de0/src/dai.sol
pragma solidity =0.5.12;

////// /nix/store/8xb41r4qd0cjb63wcrxf1qmfg88p0961-dss-6fd7de0/src/lib.sol
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.

// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

/* pragma solidity 0.5.12; */

contract LibNote {
    event LogNote(
        bytes4   indexed  sig,
        address  indexed  usr,
        bytes32  indexed  arg1,
        bytes32  indexed  arg2,
        bytes             data
    ) anonymous;

    modifier note {
        _;
        assembly {
            // log an 'anonymous' event with a constant 6 words of calldata
            // and four indexed topics: selector, caller, arg1 and arg2
            let mark := msize                         // end of memory ensures zero
            mstore(0x40, add(mark, 288))              // update free memory pointer
            mstore(mark, 0x20)                        // bytes type data offset
            mstore(add(mark, 0x20), 224)              // bytes size (padded)
            calldatacopy(add(mark, 0x40), 0, 224)     // bytes payload
            log4(mark, 288,                           // calldata
                 shl(224, shr(224, calldataload(0))), // msg.sig
                 caller,                              // msg.sender
                 calldataload(4),                     // arg1
                 calldataload(36)                     // arg2
                )
        }
    }
}

////// /nix/store/8xb41r4qd0cjb63wcrxf1qmfg88p0961-dss-6fd7de0/src/dai.sol
// Copyright (C) 2017, 2018, 2019 dbrock, rain, mrchico

// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <https://www.gnu.org/licenses/>.

/* pragma solidity 0.5.12; */

/* import "./lib.sol"; */

contract Dai is LibNote {
    // --- Auth ---
    mapping (address => uint) public wards;
    function rely(address guy) external note auth { wards[guy] = 1; }
    function deny(address guy) external note auth { wards[guy] = 0; }
    modifier auth {
        require(wards[msg.sender] == 1, "Dai/not-authorized");
        _;
    }

    // --- ERC20 Data ---
    string  public constant name     = "Dai Stablecoin";
    string  public constant symbol   = "DAI";
    string  public constant version  = "1";
    uint8   public constant decimals = 18;
    uint256 public totalSupply;

    mapping (address => uint)                      public balanceOf;
    mapping (address => mapping (address => uint)) public allowance;
    mapping (address => uint)                      public nonces;

    event Approval(address indexed src, address indexed guy, uint wad);
    event Transfer(address indexed src, address indexed dst, uint wad);

    // --- Math ---
    function add(uint x, uint y) internal pure returns (uint z) {
        require((z = x + y) >= x);
    }
    function sub(uint x, uint y) internal pure returns (uint z) {
        require((z = x - y) <= x);
    }

    // --- EIP712 niceties ---
    bytes32 public DOMAIN_SEPARATOR;
    // bytes32 public constant PERMIT_TYPEHASH = keccak256("Permit(address holder,address spender,uint256 nonce,uint256 expiry,bool allowed)");
    bytes32 public constant PERMIT_TYPEHASH = 0xea2aa0a1be11a07ed86d755c93467f4f82362b452371d1ba94d1715123511acb;

    constructor(uint256 chainId_) public {
        wards[msg.sender] = 1;
        DOMAIN_SEPARATOR = keccak256(abi.encode(
            keccak256("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)"),
            keccak256(bytes(name)),
            keccak256(bytes(version)),
            chainId_,
            address(this)
        ));
    }

    // --- Token ---
    function transfer(address dst, uint wad) external returns (bool) {
        return transferFrom(msg.sender, dst, wad);
    }
    function transferFrom(address src, address dst, uint wad)
        public returns (bool)
    {
        require(balanceOf[src] >= wad, "Dai/insufficient-balance");
        if (src != msg.sender && allowance[src][msg.sender] != uint(-1)) {
            require(allowance[src][msg.sender] >= wad, "Dai/insufficient-allowance");
            allowance[src][msg.sender] = sub(allowance[src][msg.sender], wad);
        }
        balanceOf[src] = sub(balanceOf[src], wad);
        balanceOf[dst] = add(balanceOf[dst], wad);
        emit Transfer(src, dst, wad);
        return true;
    }
    function mint(address usr, uint wad) external auth {
        balanceOf[usr] = add(balanceOf[usr], wad);
        totalSupply    = add(totalSupply, wad);
        emit Transfer(address(0), usr, wad);
    }
    function burn(address usr, uint wad) external {
        require(balanceOf[usr] >= wad, "Dai/insufficient-balance");
        if (usr != msg.sender && allowance[usr][msg.sender] != uint(-1)) {
            require(allowance[usr][msg.sender] >= wad, "Dai/insufficient-allowance");
            allowance[usr][msg.sender] = sub(allowance[usr][msg.sender], wad);
        }
        balanceOf[usr] = sub(balanceOf[usr], wad);
        totalSupply    = sub(totalSupply, wad);
        emit Transfer(usr, address(0), wad);
    }
    function approve(address usr, uint wad) external returns (bool) {
        allowance[msg.sender][usr] = wad;
        emit Approval(msg.sender, usr, wad);
        return true;
    }

    // --- Alias ---
    function push(address usr, uint wad) external {
        transferFrom(msg.sender, usr, wad);
    }
    function pull(address usr, uint wad) external {
        transferFrom(usr, msg.sender, wad);
    }
    function move(address src, address dst, uint wad) external {
        transferFrom(src, dst, wad);
    }

    // --- Approve by signature ---
    function permit(address holder, address spender, uint256 nonce, uint256 expiry,
                    bool allowed, uint8 v, bytes32 r, bytes32 s) external
    {
        bytes32 digest =
            keccak256(abi.encodePacked(
                "\x19\x01",
                DOMAIN_SEPARATOR,
                keccak256(abi.encode(PERMIT_TYPEHASH,
                                     holder,
                                     spender,
                                     nonce,
                                     expiry,
                                     allowed))
        ));

        require(holder != address(0), "Dai/invalid-address-0");
        require(holder == ecrecover(digest, v, r, s), "Dai/invalid-permit");
        require(expiry == 0 || now <= expiry, "Dai/permit-expired");
        require(nonce == nonces[holder]++, "Dai/invalid-nonce");
        uint wad = allowed ? uint(-1) : 0;
        allowance[holder][spender] = wad;
        emit Approval(holder, spender, wad);
    }
}

pragma solidity ^0.5.4;

library SafeMath {

    /**
    * @dev Multiplies two numbers, reverts on overflow.
    */
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
        // benefit is lost if 'b' is also tested.
        // See: https://github.com/OpenZeppelin/openzeppelin-solidity/pull/522
        if (a == 0) {
            return 0;
        }

        uint256 c = a * b;
        require(c / a == b);

        return c;
    }

    /**
    * @dev Integer division of two numbers truncating the quotient, reverts on division by zero.
    */
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b > 0); // Solidity only automatically asserts when dividing by 0
        uint256 c = a / b;
        // assert(a == b * c + a % b); // There is no case in which this doesn't hold

        return c;
    }

    /**
    * @dev Subtracts two numbers, reverts on overflow (i.e. if subtrahend is greater than minuend).
    */
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b <= a);
        uint256 c = a - b;

        return c;
    }

    /**
    * @dev Adds two numbers, reverts on overflow.
    */
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        require(c >= a);

        return c;
    }

    /**
    * @dev Divides two numbers and returns the remainder (unsigned integer modulo),
    * reverts when dividing by zero.
    */
    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b != 0);
        return a % b;
    }

    /**
    * @dev Returns ceil(a / b).
    */
    function ceil(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a / b;
        if(a % b == 0) {
            return c;
        }
        else {
            return c + 1;
        }
    }
}

contract Owned {

    // The owner
    address public owner;

    event OwnerChanged(address indexed _newOwner);

    /**
     * @dev Throws if the sender is not the owner.
     */
    modifier onlyOwner {
        require(msg.sender == owner, "Must be owner");
        _;
    }

    constructor() public {
        owner = msg.sender;
    }

    /**
     * @dev Lets the owner transfer ownership of the contract to a new owner.
     * @param _newOwner The new owner.
     */
    function changeOwner(address _newOwner) external onlyOwner {
        require(_newOwner != address(0), "Address must not be null");
        owner = _newOwner;
        emit OwnerChanged(_newOwner);
    }
}

contract LogicManager is Owned {

    event UpdateLogicSubmitted(address indexed logic, bool value);
    event UpdateLogicCancelled(address indexed logic);
    event UpdateLogicDone(address indexed logic, bool value);

    struct pending {
        bool value;
        uint dueTime;
    }

    // The authorized logic modules
    mapping (address => bool) public authorized;

    /*
    array
    index 0: AccountLogic address
          1: TransferLogic address
          2: DualsigsLogic address
          3: DappLogic address
          4: ...
     */
    address[] public authorizedLogics;

    // updated logics and their due time of becoming effective
    mapping (address => pending) public pendingLogics;

    // pending time before updated logics take effect
    uint public pendingTime;

    // how many authorized logics
    uint public logicCount;

    constructor(address[] memory _initialLogics, uint256 _pendingTime) public
    {
        for (uint i = 0; i < _initialLogics.length; i++) {
            address logic = _initialLogics[i];
            authorized[logic] = true;
            logicCount += 1;
        }
        authorizedLogics = _initialLogics;

        // pendingTime: 4 days for mainnet, 4 minutes for ropsten testnet
        pendingTime = _pendingTime;
    }

    function isAuthorized(address _logic) external view returns (bool) {
        return authorized[_logic];
    }

    function getAuthorizedLogics() external view returns (address[] memory) {
        return authorizedLogics;
    }

    function submitUpdate(address _logic, bool _value) external onlyOwner {
        pending storage p = pendingLogics[_logic];
        p.value = _value;
        p.dueTime = now + pendingTime;
        emit UpdateLogicSubmitted(_logic, _value);
    }

    function cancelUpdate(address _logic) external onlyOwner {
        delete pendingLogics[_logic];
        emit UpdateLogicCancelled(_logic);
    }

    function triggerUpdateLogic(address _logic) external {
        pending memory p = pendingLogics[_logic];
        require(p.dueTime > 0, "pending logic not found");
        require(p.dueTime <= now, "too early to trigger updateLogic");
        updateLogic(_logic, p.value);
        delete pendingLogics[_logic];
    }

    function updateLogic(address _logic, bool _value) internal {
        if (authorized[_logic] != _value) {
            if(_value) {
                logicCount += 1;
                authorized[_logic] = true;
                authorizedLogics.push(_logic);
            }
            else {
                logicCount -= 1;
                require(logicCount > 0, "must have at least one logic module");
                delete authorized[_logic];
                removeLogic(_logic);
            }
            emit UpdateLogicDone(_logic, _value);
        }
    }

    function removeLogic(address _logic) internal {
        uint len = authorizedLogics.length;
        address lastLogic = authorizedLogics[len - 1];
        if (_logic != lastLogic) {
            for (uint i = 0; i < len; i++) {
                 if (_logic == authorizedLogics[i]) {
                     authorizedLogics[i] = lastLogic;
                     break;
                 }
            }
        }
        authorizedLogics.length--;
    }
}

contract BaseLogic {

    bytes constant internal SIGN_HASH_PREFIX = "\x19Ethereum Signed Message:\n32";

    mapping (address => uint256) keyNonce;
    AccountStorage public accountStorage;

    modifier allowSelfCallsOnly() {
        require (msg.sender == address(this), "only internal call is allowed");
        _;
    }

    modifier allowAccountCallsOnly(Account _account) {
        require(msg.sender == address(_account), "caller must be account");
        _;
    }

    event LogicInitialised(address wallet);

    // *************** Constructor ********************** //

    constructor(AccountStorage _accountStorage) public {
        accountStorage = _accountStorage;
    }

    // *************** Initialization ********************* //

    function initAccount(Account _account) external allowAccountCallsOnly(_account){
        emit LogicInitialised(address(_account));
    }

    // *************** Getter ********************** //

    function getKeyNonce(address _key) external view returns(uint256) {
        return keyNonce[_key];
    }

    // *************** Signature ********************** //

    function getSignHash(bytes memory _data, uint256 _nonce) internal view returns(bytes32) {
        // use EIP 191
        // 0x1900 + this logic address + data + nonce of signing key
        bytes32 msgHash = keccak256(abi.encodePacked(byte(0x19), byte(0), address(this), _data, _nonce));
        bytes32 prefixedHash = keccak256(abi.encodePacked(SIGN_HASH_PREFIX, msgHash));
        return prefixedHash;
    }

    function verifySig(address _signingKey, bytes memory _signature, bytes32 _signHash) internal pure {
        require(_signingKey != address(0), "invalid signing key");
        address recoveredAddr = recover(_signHash, _signature);
        require(recoveredAddr == _signingKey, "signature verification failed");
    }

    /**
     * @dev Returns the address that signed a hashed message (`hash`) with
     * `signature`. This address can then be used for verification purposes.
     *
     * The `ecrecover` EVM opcode allows for malleable (non-unique) signatures:
     * this function rejects them by requiring the `s` value to be in the lower
     * half order, and the `v` value to be either 27 or 28.
     *
     * NOTE: This call _does not revert_ if the signature is invalid, or
     * if the signer is otherwise unable to be retrieved. In those scenarios,
     * the zero address is returned.
     *
     * IMPORTANT: `hash` _must_ be the result of a hash operation for the
     * verification to be secure: it is possible to craft signatures that
     * recover to arbitrary addresses for non-hashed data. A safe way to ensure
     * this is by receiving a hash of the original message (which may otherwise)
     * be too long), and then calling {toEthSignedMessageHash} on it.
     */
    function recover(bytes32 hash, bytes memory signature) internal pure returns (address) {
        // Check the signature length
        if (signature.length != 65) {
            return (address(0));
        }

        // Divide the signature in r, s and v variables
        bytes32 r;
        bytes32 s;
        uint8 v;

        // ecrecover takes the signature parameters, and the only way to get them
        // currently is to use assembly.
        // solhint-disable-next-line no-inline-assembly
        assembly {
            r := mload(add(signature, 0x20))
            s := mload(add(signature, 0x40))
            v := byte(0, mload(add(signature, 0x60)))
        }

        // EIP-2 still allows signature malleability for ecrecover(). Remove this possibility and make the signature
        // unique. Appendix F in the Ethereum Yellow paper (https://ethereum.github.io/yellowpaper/paper.pdf), defines
        // the valid range for s in (281): 0 < s < secp256k1n ÷ 2 + 1, and for v in (282): v ∈ {27, 28}. Most
        // signatures from current libraries generate a unique signature with an s-value in the lower half order.
        //
        // If your library generates malleable signatures, such as s-values in the upper range, calculate a new s-value
        // with 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141 - s1 and flip v from 27 to 28 or
        // vice versa. If your library also generates signatures with 0/1 for v instead 27/28, add 27 to v to accept
        // these malleable signatures as well.
        if (uint256(s) > 0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0) {
            return address(0);
        }

        if (v != 27 && v != 28) {
            return address(0);
        }

        // If the signature is valid (and not malleable), return the signer address
        return ecrecover(hash, v, r, s);
    }

    /* get signer address from data
    * @dev Gets an address encoded as the first argument in transaction data
    * @param b The byte array that should have an address as first argument
    * @returns a The address retrieved from the array
    */
    function getSignerAddress(bytes memory _b) internal pure returns (address _a) {
        require(_b.length >= 36, "invalid bytes");
        // solium-disable-next-line security/no-inline-assembly
        assembly {
            let mask := 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF
            _a := and(mask, mload(add(_b, 36)))
            // b = {length:32}{method sig:4}{address:32}{...}
            // 36 is the offset of the first parameter of the data, if encoded properly.
            // 32 bytes for the length of the bytes array, and the first 4 bytes for the function signature.
            // 32 bytes is the length of the bytes array!!!!
        }
    }

    // get method id, first 4 bytes of data
    function getMethodId(bytes memory _b) internal pure returns (bytes4 _a) {
        require(_b.length >= 4, "invalid data");
        // solium-disable-next-line security/no-inline-assembly
        assembly {
            // 32 bytes is the length of the bytes array
            _a := mload(add(_b, 32))
        }
    }

    function checkKeyStatus(address _account, uint256 _index) internal {
        // check operation key status
        if (_index > 0) {
            require(accountStorage.getKeyStatus(_account, _index) != 1, "frozen key");
        }
    }

    // _nonce is timestamp in microsecond(1/1000000 second)
    function checkAndUpdateNonce(address _key, uint256 _nonce) internal {
        require(_nonce > keyNonce[_key], "nonce too small");
        require(SafeMath.div(_nonce, 1000000) <= now + 86400, "nonce too big"); // 86400=24*3600 seconds

        keyNonce[_key] = _nonce;
    }
}

contract Account {

    // The implementation of the proxy
    address public implementation;

    // Logic manager
    address public manager;
    
    // The enabled static calls
    mapping (bytes4 => address) public enabled;

    event EnabledStaticCall(address indexed module, bytes4 indexed method);
    event Invoked(address indexed module, address indexed target, uint indexed value, bytes data);
    event Received(uint indexed value, address indexed sender, bytes data);

    event AccountInit(address indexed account);
    event ManagerChanged(address indexed mgr);

    modifier allowAuthorizedLogicContractsCallsOnly {
        require(LogicManager(manager).isAuthorized(msg.sender), "not an authorized logic");
        _;
    }

    function init(address _manager, address _accountStorage, address[] calldata _logics, address[] calldata _keys, address[] calldata _backups)
        external
    {
        require(manager == address(0), "Account: account already initialized");
        require(_manager != address(0) && _accountStorage != address(0), "Account: address is null");
        manager = _manager;

        for (uint i = 0; i < _logics.length; i++) {
            address logic = _logics[i];
            require(LogicManager(manager).isAuthorized(logic), "must be authorized logic");

            BaseLogic(logic).initAccount(this);
        }

        AccountStorage(_accountStorage).initAccount(this, _keys, _backups);

        emit AccountInit(address(this));
    }

    function invoke(address _target, uint _value, bytes calldata _data)
        external
        allowAuthorizedLogicContractsCallsOnly
        returns (bytes memory _res)
    {
        bool success;
        // solium-disable-next-line security/no-call-value
        (success, _res) = _target.call.value(_value)(_data);
        require(success, "call to target failed");
        emit Invoked(msg.sender, _target, _value, _data);
    }

    /**
    * @dev Enables a static method by specifying the target module to which the call must be delegated.
    * @param _module The target module.
    * @param _method The static method signature.
    */
    function enableStaticCall(address _module, bytes4 _method) external allowAuthorizedLogicContractsCallsOnly {
        enabled[_method] = _module;
        emit EnabledStaticCall(_module, _method);
    }

    function changeManager(address _newMgr) external allowAuthorizedLogicContractsCallsOnly {
        require(_newMgr != address(0), "address cannot be null");
        require(_newMgr != manager, "already changed");
        manager = _newMgr;
        emit ManagerChanged(_newMgr);
    }

     /**
     * @dev This method makes it possible for the wallet to comply to interfaces expecting the wallet to
     * implement specific static methods. It delegates the static call to a target contract if the data corresponds
     * to an enabled method, or logs the call otherwise.
     */
    function() external payable {
        if(msg.data.length > 0) {
            address logic = enabled[msg.sig];
            if(logic == address(0)) {
                emit Received(msg.value, msg.sender, msg.data);
            }
            else {
                require(LogicManager(manager).isAuthorized(logic), "must be an authorized logic for static call");
                // solium-disable-next-line security/no-inline-assembly
                assembly {
                    calldatacopy(0, 0, calldatasize())
                    let result := staticcall(gas, logic, 0, calldatasize(), 0, 0)
                    returndatacopy(0, 0, returndatasize())
                    switch result
                    case 0 {revert(0, returndatasize())}
                    default {return (0, returndatasize())}
                }
            }
        }
    }
}


contract AccountStorage {

    modifier allowAccountCallsOnly(Account _account) {
        require(msg.sender == address(_account), "caller must be account");
        _;
    }

    modifier allowAuthorizedLogicContractsCallsOnly(address payable _account) {
        require(LogicManager(Account(_account).manager()).isAuthorized(msg.sender), "not an authorized logic");
        _;
    }

    struct KeyItem {
        address pubKey;
        uint256 status;
    }

    struct BackupAccount {
        address backup;
        uint256 effectiveDate;//means not effective until this timestamp
        uint256 expiryDate;//means effective until this timestamp
    }

    struct DelayItem {
        bytes32 hash;
        uint256 dueTime;
    }

    struct Proposal {
        bytes32 hash;
        address[] approval;
    }

    // account => quantity of operation keys (index >= 1)
    mapping (address => uint256) operationKeyCount;

    // account => index => KeyItem
    mapping (address => mapping(uint256 => KeyItem)) keyData;

    // account => index => backup account
    mapping (address => mapping(uint256 => BackupAccount)) backupData;

    /* account => actionId => DelayItem

       delayData applies to these 4 actions:
       changeAdminKey, changeAllOperationKeys, unfreeze, changeAdminKeyByBackup
    */
    mapping (address => mapping(bytes4 => DelayItem)) delayData;

    // client account => proposer account => proposed actionId => Proposal
    mapping (address => mapping(address => mapping(bytes4 => Proposal))) proposalData;

    // *************** keyCount ********************** //

    function getOperationKeyCount(address _account) external view returns(uint256) {
        return operationKeyCount[_account];
    }

    function increaseKeyCount(address payable _account) external allowAuthorizedLogicContractsCallsOnly(_account) {
        operationKeyCount[_account] = operationKeyCount[_account] + 1;
    }

    // *************** keyData ********************** //

    function getKeyData(address _account, uint256 _index) public view returns(address) {
        KeyItem memory item = keyData[_account][_index];
        return item.pubKey;
    }

    function setKeyData(address payable _account, uint256 _index, address _key) external allowAuthorizedLogicContractsCallsOnly(_account) {
        require(_key != address(0), "invalid _key value");
        KeyItem storage item = keyData[_account][_index];
        item.pubKey = _key;
    }

    // *************** keyStatus ********************** //

    function getKeyStatus(address _account, uint256 _index) external view returns(uint256) {
        KeyItem memory item = keyData[_account][_index];
        return item.status;
    }

    function setKeyStatus(address payable _account, uint256 _index, uint256 _status) external allowAuthorizedLogicContractsCallsOnly(_account) {
        KeyItem storage item = keyData[_account][_index];
        item.status = _status;
    }

    // *************** backupData ********************** //

    function getBackupAddress(address _account, uint256 _index) external view returns(address) {
        BackupAccount memory b = backupData[_account][_index];
        return b.backup;
    }

    function getBackupEffectiveDate(address _account, uint256 _index) external view returns(uint256) {
        BackupAccount memory b = backupData[_account][_index];
        return b.effectiveDate;
    }

    function getBackupExpiryDate(address _account, uint256 _index) external view returns(uint256) {
        BackupAccount memory b = backupData[_account][_index];
        return b.expiryDate;
    }

    function setBackup(address payable _account, uint256 _index, address _backup, uint256 _effective, uint256 _expiry)
        external
        allowAuthorizedLogicContractsCallsOnly(_account)
    {
        BackupAccount storage b = backupData[_account][_index];
        b.backup = _backup;
        b.effectiveDate = _effective;
        b.expiryDate = _expiry;
    }

    function setBackupExpiryDate(address payable _account, uint256 _index, uint256 _expiry)
        external
        allowAuthorizedLogicContractsCallsOnly(_account)
    {
        BackupAccount storage b = backupData[_account][_index];
        b.expiryDate = _expiry;
    }

    function clearBackupData(address payable _account, uint256 _index) external allowAuthorizedLogicContractsCallsOnly(_account) {
        delete backupData[_account][_index];
    }

    // *************** delayData ********************** //

    function getDelayDataHash(address payable _account, bytes4 _actionId) external view returns(bytes32) {
        DelayItem memory item = delayData[_account][_actionId];
        return item.hash;
    }

    function getDelayDataDueTime(address payable _account, bytes4 _actionId) external view returns(uint256) {
        DelayItem memory item = delayData[_account][_actionId];
        return item.dueTime;
    }

    function setDelayData(address payable _account, bytes4 _actionId, bytes32 _hash, uint256 _dueTime) external allowAuthorizedLogicContractsCallsOnly(_account) {
        DelayItem storage item = delayData[_account][_actionId];
        item.hash = _hash;
        item.dueTime = _dueTime;
    }

    function clearDelayData(address payable _account, bytes4 _actionId) external allowAuthorizedLogicContractsCallsOnly(_account) {
        delete delayData[_account][_actionId];
    }

    // *************** proposalData ********************** //

    function getProposalDataHash(address _client, address _proposer, bytes4 _actionId) external view returns(bytes32) {
        Proposal memory p = proposalData[_client][_proposer][_actionId];
        return p.hash;
    }

    function getProposalDataApproval(address _client, address _proposer, bytes4 _actionId) external view returns(address[] memory) {
        Proposal memory p = proposalData[_client][_proposer][_actionId];
        return p.approval;
    }

    function setProposalData(address payable _client, address _proposer, bytes4 _actionId, bytes32 _hash, address _approvedBackup)
        external
        allowAuthorizedLogicContractsCallsOnly(_client)
    {
        Proposal storage p = proposalData[_client][_proposer][_actionId];
        if (p.hash > 0) {
            if (p.hash == _hash) {
                for (uint256 i = 0; i < p.approval.length; i++) {
                    require(p.approval[i] != _approvedBackup, "backup already exists");
                }
                p.approval.push(_approvedBackup);
            } else {
                p.hash = _hash;
                p.approval.length = 0;
            }
        } else {
            p.hash = _hash;
            p.approval.push(_approvedBackup);
        }
    }

    function clearProposalData(address payable _client, address _proposer, bytes4 _actionId) external allowAuthorizedLogicContractsCallsOnly(_client) {
        delete proposalData[_client][_proposer][_actionId];
    }


    // *************** init ********************** //
    function initAccount(Account _account, address[] calldata _keys, address[] calldata _backups)
        external
        allowAccountCallsOnly(_account)
    {
        require(getKeyData(address(_account), 0) == address(0), "AccountStorage: account already initialized!");
        require(_keys.length > 0, "empty keys array");

        operationKeyCount[address(_account)] = _keys.length - 1;

        for (uint256 index = 0; index < _keys.length; index++) {
            address _key = _keys[index];
            require(_key != address(0), "_key cannot be 0x0");
            KeyItem storage item = keyData[address(_account)][index];
            item.pubKey = _key;
            item.status = 0;
        }

        // avoid backup duplication if _backups.length > 1
        // normally won't check duplication, in most cases only one initial backup when initialization
        if (_backups.length > 1) {
            address[] memory bkps = _backups;
            for (uint256 i = 0; i < _backups.length; i++) {
                for (uint256 j = 0; j < i; j++) {
                    require(bkps[j] != _backups[i], "duplicate backup");
                }
            }
        }

        for (uint256 index = 0; index < _backups.length; index++) {
            address _backup = _backups[index];
            require(_backup != address(0), "backup cannot be 0x0");
            require(_backup != address(_account), "cannot be backup of oneself");

            backupData[address(_account)][index] = BackupAccount(_backup, now, uint256(-1));
        }
    }
}

pragma solidity ^0.5.4;

/* The MIT License (MIT)

Copyright (c) 2016 Smart Contract Solutions, Inc.

Permission is hereby granted, free of charge, to any person obtaining
a copy of this software and associated documentation files (the
"Software"), to deal in the Software without restriction, including
without limitation the rights to use, copy, modify, merge, publish,
distribute, sublicense, and/or sell copies of the Software, and to
permit persons to whom the Software is furnished to do so, subject to
the following conditions:

The above copyright notice and this permission notice shall be included
in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */

/**
 * @title SafeMath
 * @dev Math operations with safety checks that throw on error
 */
library SafeMath {

    /**
    * @dev Multiplies two numbers, reverts on overflow.
    */
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
        // benefit is lost if 'b' is also tested.
        // See: https://github.com/OpenZeppelin/openzeppelin-solidity/pull/522
        if (a == 0) {
            return 0;
        }

        uint256 c = a * b;
        require(c / a == b);

        return c;
    }

    /**
    * @dev Integer division of two numbers truncating the quotient, reverts on division by zero.
    */
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b > 0); // Solidity only automatically asserts when dividing by 0
        uint256 c = a / b;
        // assert(a == b * c + a % b); // There is no case in which this doesn't hold

        return c;
    }

    /**
    * @dev Subtracts two numbers, reverts on overflow (i.e. if subtrahend is greater than minuend).
    */
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b <= a);
        uint256 c = a - b;

        return c;
    }

    /**
    * @dev Adds two numbers, reverts on overflow.
    */
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        require(c >= a);

        return c;
    }

    /**
    * @dev Divides two numbers and returns the remainder (unsigned integer modulo),
    * reverts when dividing by zero.
    */
    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b != 0);
        return a % b;
    }

    /**
    * @dev Returns ceil(a / b).
    */
    function ceil(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a / b;
        if(a % b == 0) {
            return c;
        }
        else {
            return c + 1;
        }
    }
}

contract BaseLogic {

    bytes constant internal SIGN_HASH_PREFIX = "\x19Ethereum Signed Message:\n32";

    mapping (address => uint256) keyNonce;
    AccountStorage public accountStorage;

    modifier allowSelfCallsOnly() {
        require (msg.sender == address(this), "only internal call is allowed");
        _;
    }

    modifier allowAccountCallsOnly(Account _account) {
        require(msg.sender == address(_account), "caller must be account");
        _;
    }

    event LogicInitialised(address wallet);

    // *************** Constructor ********************** //

    constructor(AccountStorage _accountStorage) public {
        accountStorage = _accountStorage;
    }

    // *************** Initialization ********************* //

    function initAccount(Account _account) external allowAccountCallsOnly(_account){
        emit LogicInitialised(address(_account));
    }

    // *************** Getter ********************** //

    function getKeyNonce(address _key) external view returns(uint256) {
        return keyNonce[_key];
    }

    // *************** Signature ********************** //

    function getSignHash(bytes memory _data, uint256 _nonce) internal view returns(bytes32) {
        // use EIP 191
        // 0x1900 + this logic address + data + nonce of signing key
        bytes32 msgHash = keccak256(abi.encodePacked(byte(0x19), byte(0), address(this), _data, _nonce));
        bytes32 prefixedHash = keccak256(abi.encodePacked(SIGN_HASH_PREFIX, msgHash));
        return prefixedHash;
    }

    function verifySig(address _signingKey, bytes memory _signature, bytes32 _signHash) internal pure {
        require(_signingKey != address(0), "invalid signing key");
        address recoveredAddr = recover(_signHash, _signature);
        require(recoveredAddr == _signingKey, "signature verification failed");
    }

    /**
     * @dev Returns the address that signed a hashed message (`hash`) with
     * `signature`. This address can then be used for verification purposes.
     *
     * The `ecrecover` EVM opcode allows for malleable (non-unique) signatures:
     * this function rejects them by requiring the `s` value to be in the lower
     * half order, and the `v` value to be either 27 or 28.
     *
     * NOTE: This call _does not revert_ if the signature is invalid, or
     * if the signer is otherwise unable to be retrieved. In those scenarios,
     * the zero address is returned.
     *
     * IMPORTANT: `hash` _must_ be the result of a hash operation for the
     * verification to be secure: it is possible to craft signatures that
     * recover to arbitrary addresses for non-hashed data. A safe way to ensure
     * this is by receiving a hash of the original message (which may otherwise)
     * be too long), and then calling {toEthSignedMessageHash} on it.
     */
    function recover(bytes32 hash, bytes memory signature) internal pure returns (address) {
        // Check the signature length
        if (signature.length != 65) {
            return (address(0));
        }

        // Divide the signature in r, s and v variables
        bytes32 r;
        bytes32 s;
        uint8 v;

        // ecrecover takes the signature parameters, and the only way to get them
        // currently is to use assembly.
        // solhint-disable-next-line no-inline-assembly
        assembly {
            r := mload(add(signature, 0x20))
            s := mload(add(signature, 0x40))
            v := byte(0, mload(add(signature, 0x60)))
        }

        // EIP-2 still allows signature malleability for ecrecover(). Remove this possibility and make the signature
        // unique. Appendix F in the Ethereum Yellow paper (https://ethereum.github.io/yellowpaper/paper.pdf), defines
        // the valid range for s in (281): 0 < s < secp256k1n ÷ 2 + 1, and for v in (282): v ∈ {27, 28}. Most
        // signatures from current libraries generate a unique signature with an s-value in the lower half order.
        //
        // If your library generates malleable signatures, such as s-values in the upper range, calculate a new s-value
        // with 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141 - s1 and flip v from 27 to 28 or
        // vice versa. If your library also generates signatures with 0/1 for v instead 27/28, add 27 to v to accept
        // these malleable signatures as well.
        if (uint256(s) > 0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0) {
            return address(0);
        }

        if (v != 27 && v != 28) {
            return address(0);
        }

        // If the signature is valid (and not malleable), return the signer address
        return ecrecover(hash, v, r, s);
    }

    /* get signer address from data
    * @dev Gets an address encoded as the first argument in transaction data
    * @param b The byte array that should have an address as first argument
    * @returns a The address retrieved from the array
    */
    function getSignerAddress(bytes memory _b) internal pure returns (address _a) {
        require(_b.length >= 36, "invalid bytes");
        // solium-disable-next-line security/no-inline-assembly
        assembly {
            let mask := 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF
            _a := and(mask, mload(add(_b, 36)))
            // b = {length:32}{method sig:4}{address:32}{...}
            // 36 is the offset of the first parameter of the data, if encoded properly.
            // 32 bytes for the length of the bytes array, and the first 4 bytes for the function signature.
            // 32 bytes is the length of the bytes array!!!!
        }
    }

    // get method id, first 4 bytes of data
    function getMethodId(bytes memory _b) internal pure returns (bytes4 _a) {
        require(_b.length >= 4, "invalid data");
        // solium-disable-next-line security/no-inline-assembly
        assembly {
            // 32 bytes is the length of the bytes array
            _a := mload(add(_b, 32))
        }
    }

    function checkKeyStatus(address _account, uint256 _index) internal {
        // check operation key status
        if (_index > 0) {
            require(accountStorage.getKeyStatus(_account, _index) != 1, "frozen key");
        }
    }

    // _nonce is timestamp in microsecond(1/1000000 second)
    function checkAndUpdateNonce(address _key, uint256 _nonce) internal {
        require(_nonce > keyNonce[_key], "nonce too small");
        require(SafeMath.div(_nonce, 1000000) <= now + 86400, "nonce too big"); // 86400=24*3600 seconds

        keyNonce[_key] = _nonce;
    }
}

contract Owned {

    // The owner
    address public owner;

    event OwnerChanged(address indexed _newOwner);

    /**
     * @dev Throws if the sender is not the owner.
     */
    modifier onlyOwner {
        require(msg.sender == owner, "Must be owner");
        _;
    }

    constructor() public {
        owner = msg.sender;
    }

    /**
     * @dev Lets the owner transfer ownership of the contract to a new owner.
     * @param _newOwner The new owner.
     */
    function changeOwner(address _newOwner) external onlyOwner {
        require(_newOwner != address(0), "Address must not be null");
        owner = _newOwner;
        emit OwnerChanged(_newOwner);
    }
}

contract LogicManager is Owned {

    event UpdateLogicSubmitted(address indexed logic, bool value);
    event UpdateLogicCancelled(address indexed logic);
    event UpdateLogicDone(address indexed logic, bool value);

    struct pending {
        bool value;
        uint dueTime;
    }

    // The authorized logic modules
    mapping (address => bool) public authorized;

    /*
    array
    index 0: AccountLogic address
          1: TransferLogic address
          2: DualsigsLogic address
          3: DappLogic address
          4: ...
     */
    address[] public authorizedLogics;

    // updated logics and their due time of becoming effective
    mapping (address => pending) public pendingLogics;

    // pending time before updated logics take effect
    struct pendingTime {
        uint curPendingTime;
        uint nextPendingTime;
        uint dueTime;
    }

    pendingTime public pt;

    // how many authorized logics
    uint public logicCount;

    constructor(address[] memory _initialLogics, uint256 _pendingTime) public
    {
        for (uint i = 0; i < _initialLogics.length; i++) {
            address logic = _initialLogics[i];
            authorized[logic] = true;
            logicCount += 1;
        }
        authorizedLogics = _initialLogics;

        pt.curPendingTime = _pendingTime;
        pt.nextPendingTime = _pendingTime;
        pt.dueTime = now;
    }

    function submitUpdatePendingTime(uint _pendingTime) external onlyOwner {
        pt.nextPendingTime = _pendingTime;
        pt.dueTime = pt.curPendingTime + now;
    }

    function triggerUpdatePendingTime() external {
        require(pt.dueTime <= now, "too early to trigger updatePendingTime");
        pt.curPendingTime = pt.nextPendingTime;
    }

    function isAuthorized(address _logic) external view returns (bool) {
        return authorized[_logic];
    }

    function getAuthorizedLogics() external view returns (address[] memory) {
        return authorizedLogics;
    }

    function submitUpdate(address _logic, bool _value) external onlyOwner {
        pending storage p = pendingLogics[_logic];
        p.value = _value;
        p.dueTime = now + pt.curPendingTime;
        emit UpdateLogicSubmitted(_logic, _value);
    }

    function cancelUpdate(address _logic) external onlyOwner {
        delete pendingLogics[_logic];
        emit UpdateLogicCancelled(_logic);
    }

    function triggerUpdateLogic(address _logic) external {
        pending memory p = pendingLogics[_logic];
        require(p.dueTime > 0, "pending logic not found");
        require(p.dueTime <= now, "too early to trigger updateLogic");
        updateLogic(_logic, p.value);
        delete pendingLogics[_logic];
    }

    function updateLogic(address _logic, bool _value) internal {
        if (authorized[_logic] != _value) {
            if(_value) {
                logicCount += 1;
                authorized[_logic] = true;
                authorizedLogics.push(_logic);
            }
            else {
                logicCount -= 1;
                require(logicCount > 0, "must have at least one logic module");
                delete authorized[_logic];
                removeLogic(_logic);
            }
            emit UpdateLogicDone(_logic, _value);
        }
    }

    function removeLogic(address _logic) internal {
        uint len = authorizedLogics.length;
        address lastLogic = authorizedLogics[len - 1];
        if (_logic != lastLogic) {
            for (uint i = 0; i < len; i++) {
                 if (_logic == authorizedLogics[i]) {
                     authorizedLogics[i] = lastLogic;
                     break;
                 }
            }
        }
        authorizedLogics.length--;
    }
}


contract AccountStorage {

    modifier allowAccountCallsOnly(Account _account) {
        require(msg.sender == address(_account), "caller must be account");
        _;
    }

    modifier allowAuthorizedLogicContractsCallsOnly(address payable _account) {
        require(LogicManager(Account(_account).manager()).isAuthorized(msg.sender), "not an authorized logic");
        _;
    }

    struct KeyItem {
        address pubKey;
        uint256 status;
    }

    struct BackupAccount {
        address backup;
        uint256 effectiveDate;//means not effective until this timestamp
        uint256 expiryDate;//means effective until this timestamp
    }

    struct DelayItem {
        bytes32 hash;
        uint256 dueTime;
    }

    struct Proposal {
        bytes32 hash;
        address[] approval;
    }

    // account => quantity of operation keys (index >= 1)
    mapping (address => uint256) operationKeyCount;

    // account => index => KeyItem
    mapping (address => mapping(uint256 => KeyItem)) keyData;

    // account => index => backup account
    mapping (address => mapping(uint256 => BackupAccount)) backupData;

    /* account => actionId => DelayItem

       delayData applies to these 4 actions:
       changeAdminKey, changeAllOperationKeys, unfreeze, changeAdminKeyByBackup
    */
    mapping (address => mapping(bytes4 => DelayItem)) delayData;

    // client account => proposer account => proposed actionId => Proposal
    mapping (address => mapping(address => mapping(bytes4 => Proposal))) proposalData;

    // *************** keyCount ********************** //

    function getOperationKeyCount(address _account) external view returns(uint256) {
        return operationKeyCount[_account];
    }

    function increaseKeyCount(address payable _account) external allowAuthorizedLogicContractsCallsOnly(_account) {
        operationKeyCount[_account] = operationKeyCount[_account] + 1;
    }

    // *************** keyData ********************** //

    function getKeyData(address _account, uint256 _index) public view returns(address) {
        KeyItem memory item = keyData[_account][_index];
        return item.pubKey;
    }

    function setKeyData(address payable _account, uint256 _index, address _key) external allowAuthorizedLogicContractsCallsOnly(_account) {
        require(_key != address(0), "invalid _key value");
        KeyItem storage item = keyData[_account][_index];
        item.pubKey = _key;
    }

    // *************** keyStatus ********************** //

    function getKeyStatus(address _account, uint256 _index) external view returns(uint256) {
        KeyItem memory item = keyData[_account][_index];
        return item.status;
    }

    function setKeyStatus(address payable _account, uint256 _index, uint256 _status) external allowAuthorizedLogicContractsCallsOnly(_account) {
        KeyItem storage item = keyData[_account][_index];
        item.status = _status;
    }

    // *************** backupData ********************** //

    function getBackupAddress(address _account, uint256 _index) external view returns(address) {
        BackupAccount memory b = backupData[_account][_index];
        return b.backup;
    }

    function getBackupEffectiveDate(address _account, uint256 _index) external view returns(uint256) {
        BackupAccount memory b = backupData[_account][_index];
        return b.effectiveDate;
    }

    function getBackupExpiryDate(address _account, uint256 _index) external view returns(uint256) {
        BackupAccount memory b = backupData[_account][_index];
        return b.expiryDate;
    }

    function setBackup(address payable _account, uint256 _index, address _backup, uint256 _effective, uint256 _expiry)
        external
        allowAuthorizedLogicContractsCallsOnly(_account)
    {
        BackupAccount storage b = backupData[_account][_index];
        b.backup = _backup;
        b.effectiveDate = _effective;
        b.expiryDate = _expiry;
    }

    function setBackupExpiryDate(address payable _account, uint256 _index, uint256 _expiry)
        external
        allowAuthorizedLogicContractsCallsOnly(_account)
    {
        BackupAccount storage b = backupData[_account][_index];
        b.expiryDate = _expiry;
    }

    function clearBackupData(address payable _account, uint256 _index) external allowAuthorizedLogicContractsCallsOnly(_account) {
        delete backupData[_account][_index];
    }

    // *************** delayData ********************** //

    function getDelayDataHash(address payable _account, bytes4 _actionId) external view returns(bytes32) {
        DelayItem memory item = delayData[_account][_actionId];
        return item.hash;
    }

    function getDelayDataDueTime(address payable _account, bytes4 _actionId) external view returns(uint256) {
        DelayItem memory item = delayData[_account][_actionId];
        return item.dueTime;
    }

    function setDelayData(address payable _account, bytes4 _actionId, bytes32 _hash, uint256 _dueTime) external allowAuthorizedLogicContractsCallsOnly(_account) {
        DelayItem storage item = delayData[_account][_actionId];
        item.hash = _hash;
        item.dueTime = _dueTime;
    }

    function clearDelayData(address payable _account, bytes4 _actionId) external allowAuthorizedLogicContractsCallsOnly(_account) {
        delete delayData[_account][_actionId];
    }

    // *************** proposalData ********************** //

    function getProposalDataHash(address _client, address _proposer, bytes4 _actionId) external view returns(bytes32) {
        Proposal memory p = proposalData[_client][_proposer][_actionId];
        return p.hash;
    }

    function getProposalDataApproval(address _client, address _proposer, bytes4 _actionId) external view returns(address[] memory) {
        Proposal memory p = proposalData[_client][_proposer][_actionId];
        return p.approval;
    }

    function setProposalData(address payable _client, address _proposer, bytes4 _actionId, bytes32 _hash, address _approvedBackup)
        external
        allowAuthorizedLogicContractsCallsOnly(_client)
    {
        Proposal storage p = proposalData[_client][_proposer][_actionId];
        if (p.hash > 0) {
            if (p.hash == _hash) {
                for (uint256 i = 0; i < p.approval.length; i++) {
                    require(p.approval[i] != _approvedBackup, "backup already exists");
                }
                p.approval.push(_approvedBackup);
            } else {
                p.hash = _hash;
                p.approval.length = 0;
            }
        } else {
            p.hash = _hash;
            p.approval.push(_approvedBackup);
        }
    }

    function clearProposalData(address payable _client, address _proposer, bytes4 _actionId) external allowAuthorizedLogicContractsCallsOnly(_client) {
        delete proposalData[_client][_proposer][_actionId];
    }


    // *************** init ********************** //
    function initAccount(Account _account, address[] calldata _keys, address[] calldata _backups)
        external
        allowAccountCallsOnly(_account)
    {
        require(getKeyData(address(_account), 0) == address(0), "AccountStorage: account already initialized!");
        require(_keys.length > 0, "empty keys array");

        operationKeyCount[address(_account)] = _keys.length - 1;

        for (uint256 index = 0; index < _keys.length; index++) {
            address _key = _keys[index];
            require(_key != address(0), "_key cannot be 0x0");
            KeyItem storage item = keyData[address(_account)][index];
            item.pubKey = _key;
            item.status = 0;
        }

        // avoid backup duplication if _backups.length > 1
        // normally won't check duplication, in most cases only one initial backup when initialization
        if (_backups.length > 1) {
            address[] memory bkps = _backups;
            for (uint256 i = 0; i < _backups.length; i++) {
                for (uint256 j = 0; j < i; j++) {
                    require(bkps[j] != _backups[i], "duplicate backup");
                }
            }
        }

        for (uint256 index = 0; index < _backups.length; index++) {
            address _backup = _backups[index];
            require(_backup != address(0), "backup cannot be 0x0");
            require(_backup != address(_account), "cannot be backup of oneself");

            backupData[address(_account)][index] = BackupAccount(_backup, now, uint256(-1));
        }
    }
}

contract Account {

    // The implementation of the proxy
    address public implementation;

    // Logic manager
    address public manager;
    
    // The enabled static calls
    mapping (bytes4 => address) public enabled;

    event EnabledStaticCall(address indexed module, bytes4 indexed method);
    event Invoked(address indexed module, address indexed target, uint indexed value, bytes data);
    event Received(uint indexed value, address indexed sender, bytes data);

    event AccountInit(address indexed account);
    event ManagerChanged(address indexed mgr);

    modifier allowAuthorizedLogicContractsCallsOnly {
        require(LogicManager(manager).isAuthorized(msg.sender), "not an authorized logic");
        _;
    }

    function init(address _manager, address _accountStorage, address[] calldata _logics, address[] calldata _keys, address[] calldata _backups)
        external
    {
        require(manager == address(0), "Account: account already initialized");
        require(_manager != address(0) && _accountStorage != address(0), "Account: address is null");
        manager = _manager;

        for (uint i = 0; i < _logics.length; i++) {
            address logic = _logics[i];
            require(LogicManager(manager).isAuthorized(logic), "must be authorized logic");

            BaseLogic(logic).initAccount(this);
        }

        AccountStorage(_accountStorage).initAccount(this, _keys, _backups);

        emit AccountInit(address(this));
    }

    function invoke(address _target, uint _value, bytes calldata _data)
        external
        allowAuthorizedLogicContractsCallsOnly
        returns (bytes memory _res)
    {
        bool success;
        // solium-disable-next-line security/no-call-value
        (success, _res) = _target.call.value(_value)(_data);
        require(success, "call to target failed");
        emit Invoked(msg.sender, _target, _value, _data);
    }

    /**
    * @dev Enables a static method by specifying the target module to which the call must be delegated.
    * @param _module The target module.
    * @param _method The static method signature.
    */
    function enableStaticCall(address _module, bytes4 _method) external allowAuthorizedLogicContractsCallsOnly {
        enabled[_method] = _module;
        emit EnabledStaticCall(_module, _method);
    }

    function changeManager(address _newMgr) external allowAuthorizedLogicContractsCallsOnly {
        require(_newMgr != address(0), "address cannot be null");
        require(_newMgr != manager, "already changed");
        manager = _newMgr;
        emit ManagerChanged(_newMgr);
    }

     /**
     * @dev This method makes it possible for the wallet to comply to interfaces expecting the wallet to
     * implement specific static methods. It delegates the static call to a target contract if the data corresponds
     * to an enabled method, or logs the call otherwise.
     */
    function() external payable {
        if(msg.data.length > 0) {
            address logic = enabled[msg.sig];
            if(logic == address(0)) {
                emit Received(msg.value, msg.sender, msg.data);
            }
            else {
                require(LogicManager(manager).isAuthorized(logic), "must be an authorized logic for static call");
                // solium-disable-next-line security/no-inline-assembly
                assembly {
                    calldatacopy(0, 0, calldatasize())
                    let result := staticcall(gas, logic, 0, calldatasize(), 0, 0)
                    returndatacopy(0, 0, returndatasize())
                    switch result
                    case 0 {revert(0, returndatasize())}
                    default {return (0, returndatasize())}
                }
            }
        }
    }
}

pragma solidity ^0.5.4;

contract Owned {

    // The owner
    address public owner;

    event OwnerChanged(address indexed _newOwner);

    /**
     * @dev Throws if the sender is not the owner.
     */
    modifier onlyOwner {
        require(msg.sender == owner, "Must be owner");
        _;
    }

    constructor() public {
        owner = msg.sender;
    }

    /**
     * @dev Lets the owner transfer ownership of the contract to a new owner.
     * @param _newOwner The new owner.
     */
    function changeOwner(address _newOwner) external onlyOwner {
        require(_newOwner != address(0), "Address must not be null");
        owner = _newOwner;
        emit OwnerChanged(_newOwner);
    }
}

contract LogicManager is Owned {

    event UpdateLogicSubmitted(address indexed logic, bool value);
    event UpdateLogicCancelled(address indexed logic);
    event UpdateLogicDone(address indexed logic, bool value);

    struct pending {
        bool value;
        uint dueTime;
    }

    // The authorized logic modules
    mapping (address => bool) public authorized;

    /*
    array
    index 0: AccountLogic address
          1: TransferLogic address
          2: DualsigsLogic address
          3: DappLogic address
          4: ...
     */
    address[] public authorizedLogics;

    // updated logics and their due time of becoming effective
    mapping (address => pending) public pendingLogics;

    // pending time before updated logics take effect
    struct pendingTime {
        uint curPendingTime;
        uint nextPendingTime;
        uint dueTime;
    }

    pendingTime public pt;

    // how many authorized logics
    uint public logicCount;

    constructor(address[] memory _initialLogics, uint256 _pendingTime) public
    {
        for (uint i = 0; i < _initialLogics.length; i++) {
            address logic = _initialLogics[i];
            authorized[logic] = true;
            logicCount += 1;
        }
        authorizedLogics = _initialLogics;

        pt.curPendingTime = _pendingTime;
        pt.nextPendingTime = _pendingTime;
        pt.dueTime = now;
    }

    function submitUpdatePendingTime(uint _pendingTime) external onlyOwner {
        pt.nextPendingTime = _pendingTime;
        pt.dueTime = pt.curPendingTime + now;
    }

    function triggerUpdatePendingTime() external {
        require(pt.dueTime <= now, "too early to trigger updatePendingTime");
        pt.curPendingTime = pt.nextPendingTime;
    }

    function isAuthorized(address _logic) external view returns (bool) {
        return authorized[_logic];
    }

    function getAuthorizedLogics() external view returns (address[] memory) {
        return authorizedLogics;
    }

    function submitUpdate(address _logic, bool _value) external onlyOwner {
        pending storage p = pendingLogics[_logic];
        p.value = _value;
        p.dueTime = now + pt.curPendingTime;
        emit UpdateLogicSubmitted(_logic, _value);
    }

    function cancelUpdate(address _logic) external onlyOwner {
        delete pendingLogics[_logic];
        emit UpdateLogicCancelled(_logic);
    }

    function triggerUpdateLogic(address _logic) external {
        pending memory p = pendingLogics[_logic];
        require(p.dueTime > 0, "pending logic not found");
        require(p.dueTime <= now, "too early to trigger updateLogic");
        updateLogic(_logic, p.value);
        delete pendingLogics[_logic];
    }

    function updateLogic(address _logic, bool _value) internal {
        if (authorized[_logic] != _value) {
            if(_value) {
                logicCount += 1;
                authorized[_logic] = true;
                authorizedLogics.push(_logic);
            }
            else {
                logicCount -= 1;
                require(logicCount > 0, "must have at least one logic module");
                delete authorized[_logic];
                removeLogic(_logic);
            }
            emit UpdateLogicDone(_logic, _value);
        }
    }

    function removeLogic(address _logic) internal {
        uint len = authorizedLogics.length;
        address lastLogic = authorizedLogics[len - 1];
        if (_logic != lastLogic) {
            for (uint i = 0; i < len; i++) {
                 if (_logic == authorizedLogics[i]) {
                     authorizedLogics[i] = lastLogic;
                     break;
                 }
            }
        }
        authorizedLogics.length--;
    }
}

pragma solidity ^0.4.16;

contract DSMath {
    function add(uint x, uint y) internal pure returns (uint z) {
        require((z = x + y) >= x);
    }
    function sub(uint x, uint y) internal pure returns (uint z) {
        require((z = x - y) <= x);
    }
    function mul(uint x, uint y) internal pure returns (uint z) {
        require(y == 0 || (z = x * y) / y == x);
    }

    function min(uint x, uint y) internal pure returns (uint z) {
        return x <= y ? x : y;
    }
    function max(uint x, uint y) internal pure returns (uint z) {
        return x >= y ? x : y;
    }
    function imin(int x, int y) internal pure returns (int z) {
        return x <= y ? x : y;
    }
    function imax(int x, int y) internal pure returns (int z) {
        return x >= y ? x : y;
    }

    uint constant WAD = 10 ** 18;
    uint constant RAY = 10 ** 27;

    function wmul(uint x, uint y) internal pure returns (uint z) {
        z = add(mul(x, y), WAD / 2) / WAD;
    }
    function rmul(uint x, uint y) internal pure returns (uint z) {
        z = add(mul(x, y), RAY / 2) / RAY;
    }
    function wdiv(uint x, uint y) internal pure returns (uint z) {
        z = add(mul(x, WAD), y / 2) / y;
    }
    function rdiv(uint x, uint y) internal pure returns (uint z) {
        z = add(mul(x, RAY), y / 2) / y;
    }

    // This famous algorithm is called "exponentiation by squaring"
    // and calculates x^n with x as fixed-point and n as regular unsigned.
    //
    // It's O(log n), instead of O(n) for naive repeated multiplication.
    //
    // These facts are why it works:
    //
    //  If n is even, then x^n = (x^2)^(n/2).
    //  If n is odd,  then x^n = x * x^(n-1),
    //   and applying the equation for even x gives
    //    x^n = x * (x^2)^((n-1) / 2).
    //
    //  Also, EVM division is flooring and
    //    floor[(n-1) / 2] = floor[n / 2].
    //
    function rpow(uint x, uint n) internal pure returns (uint z) {
        z = n % 2 != 0 ? x : RAY;

        for (n /= 2; n != 0; n /= 2) {
            x = rmul(x, x);

            if (n % 2 != 0) {
                z = rmul(z, x);
            }
        }
    }
}

contract OtcInterface {
    function sellAllAmount(address, uint, address, uint) public returns (uint);
    function buyAllAmount(address, uint, address, uint) public returns (uint);
    function getPayAmount(address, address, uint) public constant returns (uint);
}

contract TokenInterface {
    function balanceOf(address) public returns (uint);
    function allowance(address, address) public returns (uint);
    function approve(address, uint) public;
    function transfer(address,uint) public returns (bool);
    function transferFrom(address, address, uint) public returns (bool);
    function deposit() public payable;
    function withdraw(uint) public;
}

contract OasisDirectProxy is DSMath {
    function withdrawAndSend(TokenInterface wethToken, uint wethAmt) internal {
        wethToken.withdraw(wethAmt);
        require(msg.sender.call.value(wethAmt)());
    }

    function sellAllAmount(OtcInterface otc, TokenInterface payToken, uint payAmt, TokenInterface buyToken, uint minBuyAmt) public returns (uint buyAmt) {
        require(payToken.transferFrom(msg.sender, this, payAmt));
        if (payToken.allowance(this, otc) < payAmt) {
            payToken.approve(otc, uint(-1));
        }
        buyAmt = otc.sellAllAmount(payToken, payAmt, buyToken, minBuyAmt);
        require(buyToken.transfer(msg.sender, buyAmt));
    }

    function sellAllAmountPayEth(OtcInterface otc, TokenInterface wethToken, TokenInterface buyToken, uint minBuyAmt) public payable returns (uint buyAmt) {
        wethToken.deposit.value(msg.value)();
        if (wethToken.allowance(this, otc) < msg.value) {
            wethToken.approve(otc, uint(-1));
        }
        buyAmt = otc.sellAllAmount(wethToken, msg.value, buyToken, minBuyAmt);
        require(buyToken.transfer(msg.sender, buyAmt));
    }

    function sellAllAmountBuyEth(OtcInterface otc, TokenInterface payToken, uint payAmt, TokenInterface wethToken, uint minBuyAmt) public returns (uint wethAmt) {
        require(payToken.transferFrom(msg.sender, this, payAmt));
        if (payToken.allowance(this, otc) < payAmt) {
            payToken.approve(otc, uint(-1));
        }
        wethAmt = otc.sellAllAmount(payToken, payAmt, wethToken, minBuyAmt);
        withdrawAndSend(wethToken, wethAmt);
    }

    function buyAllAmount(OtcInterface otc, TokenInterface buyToken, uint buyAmt, TokenInterface payToken, uint maxPayAmt) public returns (uint payAmt) {
        uint payAmtNow = otc.getPayAmount(payToken, buyToken, buyAmt);
        require(payAmtNow <= maxPayAmt);
        require(payToken.transferFrom(msg.sender, this, payAmtNow));
        if (payToken.allowance(this, otc) < payAmtNow) {
            payToken.approve(otc, uint(-1));
        }
        payAmt = otc.buyAllAmount(buyToken, buyAmt, payToken, payAmtNow);
        require(buyToken.transfer(msg.sender, min(buyAmt, buyToken.balanceOf(this)))); // To avoid rounding issues we check the minimum value
    }

    function buyAllAmountPayEth(OtcInterface otc, TokenInterface buyToken, uint buyAmt, TokenInterface wethToken) public payable returns (uint wethAmt) {
        // In this case user needs to send more ETH than a estimated value, then contract will send back the rest
        wethToken.deposit.value(msg.value)();
        if (wethToken.allowance(this, otc) < msg.value) {
            wethToken.approve(otc, uint(-1));
        }
        wethAmt = otc.buyAllAmount(buyToken, buyAmt, wethToken, msg.value);
        require(buyToken.transfer(msg.sender, min(buyAmt, buyToken.balanceOf(this)))); // To avoid rounding issues we check the minimum value
        withdrawAndSend(wethToken, sub(msg.value, wethAmt));
    }

    function buyAllAmountBuyEth(OtcInterface otc, TokenInterface wethToken, uint wethAmt, TokenInterface payToken, uint maxPayAmt) public returns (uint payAmt) {
        uint payAmtNow = otc.getPayAmount(payToken, wethToken, wethAmt);
        require(payAmtNow <= maxPayAmt);
        require(payToken.transferFrom(msg.sender, this, payAmtNow));
        if (payToken.allowance(this, otc) < payAmtNow) {
            payToken.approve(otc, uint(-1));
        }
        payAmt = otc.buyAllAmount(wethToken, wethAmt, payToken, payAmtNow);
        withdrawAndSend(wethToken, wethAmt);
    }

    function() public payable {}
}

contract DSAuthority {
    function canCall(
        address src, address dst, bytes4 sig
    ) public view returns (bool);
}

contract DSAuthEvents {
    event LogSetAuthority (address indexed authority);
    event LogSetOwner     (address indexed owner);
}

contract DSAuth is DSAuthEvents {
    DSAuthority  public  authority;
    address      public  owner;

    function DSAuth() public {
        owner = msg.sender;
        LogSetOwner(msg.sender);
    }

    function setOwner(address owner_)
        public
        auth
    {
        owner = owner_;
        LogSetOwner(owner);
    }

    function setAuthority(DSAuthority authority_)
        public
        auth
    {
        authority = authority_;
        LogSetAuthority(authority);
    }

    modifier auth {
        require(isAuthorized(msg.sender, msg.sig));
        _;
    }

    function isAuthorized(address src, bytes4 sig) internal view returns (bool) {
        if (src == address(this)) {
            return true;
        } else if (src == owner) {
            return true;
        } else if (authority == DSAuthority(0)) {
            return false;
        } else {
            return authority.canCall(src, this, sig);
        }
    }
}

contract DSNote {
    event LogNote(
        bytes4   indexed  sig,
        address  indexed  guy,
        bytes32  indexed  foo,
        bytes32  indexed  bar,
        uint              wad,
        bytes             fax
    ) anonymous;

    modifier note {
        bytes32 foo;
        bytes32 bar;

        assembly {
            foo := calldataload(4)
            bar := calldataload(36)
        }

        LogNote(msg.sig, msg.sender, foo, bar, msg.value, msg.data);

        _;
    }
}

// DSProxy
// Allows code execution using a persistant identity This can be very
// useful to execute a sequence of atomic actions. Since the owner of
// the proxy can be changed, this allows for dynamic ownership models
// i.e. a multisig
contract DSProxy is DSAuth, DSNote {
    DSProxyCache public cache;  // global cache for contracts

    function DSProxy(address _cacheAddr) public {
        require(setCache(_cacheAddr));
    }

    function() public payable {
    }

    // use the proxy to execute calldata _data on contract _code
    function execute(bytes _code, bytes _data)
        public
        payable
        returns (address target, bytes32 response)
    {
        target = cache.read(_code);
        if (target == 0x0) {
            // deploy contract & store its address in cache
            target = cache.write(_code);
        }

        response = execute(target, _data);
    }

    function execute(address _target, bytes _data)
        public
        auth
        note
        payable
        returns (bytes32 response)
    {
        require(_target != 0x0);

        // call contract in current context
        assembly {
            let succeeded := delegatecall(sub(gas, 5000), _target, add(_data, 0x20), mload(_data), 0, 32)
            response := mload(0)      // load delegatecall output
            switch iszero(succeeded)
            case 1 {
                // throw if delegatecall failed
                revert(0, 0)
            }
        }
    }

    //set new cache
    function setCache(address _cacheAddr)
        public
        auth
        note
        returns (bool)
    {
        require(_cacheAddr != 0x0);        // invalid cache address
        cache = DSProxyCache(_cacheAddr);  // overwrite cache
        return true;
    }
}

// DSProxyFactory
// This factory deploys new proxy instances through build()
// Deployed proxy addresses are logged
contract DSProxyFactory {
    event Created(address indexed sender, address proxy, address cache);
    mapping(address=>bool) public isProxy;
    DSProxyCache public cache = new DSProxyCache();

    // deploys a new proxy instance
    // sets owner of proxy to caller
    function build() public returns (DSProxy proxy) {
        proxy = build(msg.sender);
    }

    // deploys a new proxy instance
    // sets custom owner of proxy
    function build(address owner) public returns (DSProxy proxy) {
        proxy = new DSProxy(cache);
        Created(owner, address(proxy), address(cache));
        proxy.setOwner(owner);
        isProxy[proxy] = true;
    }
}

// DSProxyCache
// This global cache stores addresses of contracts previously deployed
// by a proxy. This saves gas from repeat deployment of the same
// contracts and eliminates blockchain bloat.

// By default, all proxies deployed from the same factory store
// contracts in the same cache. The cache a proxy instance uses can be
// changed.  The cache uses the sha3 hash of a contract's bytecode to
// lookup the address
contract DSProxyCache {
    mapping(bytes32 => address) cache;

    function read(bytes _code) public view returns (address) {
        bytes32 hash = keccak256(_code);
        return cache[hash];
    }

    function write(bytes _code) public returns (address target) {
        assembly {
            target := create(0, add(_code, 0x20), mload(_code))
            switch iszero(extcodesize(target))
            case 1 {
                // throw if contract failed to deploy
                revert(0, 0)
            }
        }
        bytes32 hash = keccak256(_code);
        cache[hash] = target;
    }
}

contract ProxyCreationAndExecute is OasisDirectProxy {
    TokenInterface wethToken;

    function ProxyCreationAndExecute(address wethToken_) {
        wethToken = TokenInterface(wethToken_);
    }

    function createAndSellAllAmount(DSProxyFactory factory, OtcInterface otc, TokenInterface payToken, uint payAmt, TokenInterface buyToken, uint minBuyAmt) public returns (DSProxy proxy, uint buyAmt) {
        proxy = factory.build(msg.sender);
        buyAmt = sellAllAmount(otc, payToken, payAmt, buyToken, minBuyAmt);
    }

    function createAndSellAllAmountPayEth(DSProxyFactory factory, OtcInterface otc, TokenInterface buyToken, uint minBuyAmt) public payable returns (DSProxy proxy, uint buyAmt) {
        proxy = factory.build(msg.sender);
        buyAmt = sellAllAmountPayEth(otc, wethToken, buyToken, minBuyAmt);
    }

    function createAndSellAllAmountBuyEth(DSProxyFactory factory, OtcInterface otc, TokenInterface payToken, uint payAmt, uint minBuyAmt) public returns (DSProxy proxy, uint wethAmt) {
        proxy = factory.build(msg.sender);
        wethAmt = sellAllAmountBuyEth(otc, payToken, payAmt, wethToken, minBuyAmt);
    }

    function createAndBuyAllAmount(DSProxyFactory factory, OtcInterface otc, TokenInterface buyToken, uint buyAmt, TokenInterface payToken, uint maxPayAmt) public returns (DSProxy proxy, uint payAmt) {
        proxy = factory.build(msg.sender);
        payAmt = buyAllAmount(otc, buyToken, buyAmt, payToken, maxPayAmt);
    }

    function createAndBuyAllAmountPayEth(DSProxyFactory factory, OtcInterface otc, TokenInterface buyToken, uint buyAmt) public payable returns (DSProxy proxy, uint wethAmt) {
        proxy = factory.build(msg.sender);
        wethAmt = buyAllAmountPayEth(otc, buyToken, buyAmt, wethToken);
    }

    function createAndBuyAllAmountBuyEth(DSProxyFactory factory, OtcInterface otc, uint wethAmt, TokenInterface payToken, uint maxPayAmt) public returns (DSProxy proxy, uint payAmt) {
        proxy = factory.build(msg.sender);
        payAmt = buyAllAmountBuyEth(otc, wethToken, wethAmt, payToken, maxPayAmt);
    }

    function() public payable {
        require(msg.sender == address(wethToken));
    }
}