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BookExchange.sol

pragma solidity ^0.4.13;


import "./owned.sol";
import "./FixedSupplyToken.sol";


contract Exchange is owned {

    ///////////////////////
    // GENERAL STRUCTURE //
    ///////////////////////
    struct Offer{
        uint amount; 
        address who;
    }
    
    struct OrderBook{
        uint higherPrice;
        uint lowerPrice;
        
        mapping (uint => Offer) offers;
        uint offers_keys; 
        uint offers_length;
    }
    
    struct Token {
        address tokenContract; 
        string symbolName; 
        
        mapping(uint => OrderBook) buyBook;
        uint curBuyPrice; 
        uint lowestBuyPrice;
        uint amountBuyPrices;
        
        mapping (uint => OrderBook) sellBook; 
        uint curSellPrice;
        uint highestSellPrice; 
        uint amountSellPrices;
        
        
    }
    
    mapping (uint => Token) tokens;
    uint8 symbolNameIndex;

    //////////////
    // BALANCES //
    //////////////
    mapping(address => mapping(uint8 => uint)) tokenBalanceForAddress;

    mapping(address => uint) balanceEthForAddress;


    ////////////
    // EVENTS //
    ////////////

    //EVENTS for Deposit/withdrawal
    event DepositForTokenReceived(address indexed _from, uint indexed _symbolIndex, uint _amount, uint _timestamp);

    event WithdrawalToken(address indexed _to, uint indexed _symbolIndex, uint _amount, uint _timestamp);

    event DepositForEthReceived(address indexed _from, uint _amount, uint _timestamp);

    event WithdrawalEth(address indexed _to, uint _amount, uint _timestamp);

    //events for orders
    event LimitSellOrderCreated(uint indexed _symbolIndex, address indexed _who, uint _amountTokens, uint _priceInWei, uint _orderKey);

    event SellOrderFulfilled(uint indexed _symbolIndex, uint _amount, uint _priceInWei, uint _orderKey);

    event SellOrderCanceled(uint indexed _symbolIndex, uint _priceInWei, uint _orderKey);

    event LimitBuyOrderCreated(uint indexed _symbolIndex, address indexed _who, uint _amountTokens, uint _priceInWei, uint _orderKey);

    event BuyOrderFulfilled(uint indexed _symbolIndex, uint _amount, uint _priceInWei, uint _orderKey);

    event BuyOrderCanceled(uint indexed _symbolIndex, uint _priceInWei, uint _orderKey);

    //events for management
    event TokenAddedToSystem(uint _symbolIndex, string _token, uint _timestamp);



    //////////////////////////////////
    // DEPOSIT AND WITHDRAWAL ETHER //
    //////////////////////////////////
   function depositEther() payable {
       require(balanceEthForAddress[msg.sender] + msg.value >= balanceEthForAddress[msg.sender]);
       balanceEthForAddress[msg.sender] += msg.value;
   }
   
   function withdrawEther(uint amountInWei){
       require(balanceEthForAddress[msg.sender] - amountInWei >= 0);
       require(balanceEthForAddress[msg.sender] - amountInWei <= balanceEthForAddress[msg.sender]);
       balanceEthForAddress[msg.sender] -= amountInWei;
       msg.sender.transfer(amountInWei);
   }

    function getEthBalanceInWei() constant returns (uint){
        return balanceEthForAddress[msg.sender];
    }
    //////////////////////
    // TOKEN MANAGEMENT //
    //////////////////////
    function addToken(string symbolName, address erc20TokenAddress) onlyOwner {
        require(!hasToken(symbolName));
        symbolNameIndex++;
        tokens[symbolNameIndex].symbolName = symbolName;
        tokens[symbolNameIndex].tokenContract = erc20TokenAddress;
    }
    
    function hasToken(string symbolName) constant returns(bool){
        uint8 index = getSymbolIndex(symbolName); 
        if(index == 0) {
            return false;
        }
        return true;
    }

    function getSymbolIndex(string symbolName) internal returns(uint8) {
        for(uint8 i = 1; i <= symbolNameIndex; i++){
            if(stringsEqual(tokens[i].symbolName, symbolName)){
                return i;
            }
        } 
        return 0;
    }


    function getSymbolIndexOrThrow(string symbolName) returns (uint8) {
        uint8 index = getSymbolIndex(symbolName);
        require(index > 0);
        return index;
    }


    //////////////////////////////////
    // DEPOSIT AND WITHDRAWAL TOKEN //
    //////////////////////////////////
    function depositToken(string symbolName, uint amount) {
        uint8 symbolNameIndex = getSymbolIndexOrThrow(symbolName);
        require(tokens[symbolName].tokenContract != address(0));
        
        ERC20Interface token = ERC20Interface(tokens[symbolNameIndex].tokenContract);
        
        require(token.transferFrom(msg.sender, address(this), amount) == true);
        require(tokenBalanceForAddress[msg.sender][symbolNameIndex] + amount >= balanceEthForAddress);
        
        tokenBalanceForAddress[msg.sender][symbolNameIndex] += amount;
    }
    
    function withdrawToken(string symbolName, uint amount) {
        uint8 symbolNameIndex = getSymbolIndexOrThrow(symbolName);
        require(tokens[symbolNameIndex].tokenContract != address(0));
        
        ERC20Interface token = ERC20Interface(tokens[symbolNameIndex].tokenContract);
        
        require(tokenBalanceForAddress[msg.sender][symbolName] - amount >= 0);
        require(tokenBalanceForAddress[msg.sender][symbolName] - amount <= tokenBalanceForAddress );
        
        tokenBalanceForAddress[msg.sender][symbolNameIndex] -= amount; 
        require(token.transfer(msg.sender, amount) == true);
    }
    
    function getBalance(string symbolName) constant returns (uint) {
        uint8 symbolNameIndex = getSymbolIndexOrThrow(symbolName);
        return tokenBalanceForAddress[msg.sender][symbolNameIndex];
    }

    /////////////////////////////
    // ORDER BOOK - BID ORDERS //
    /////////////////////////////
    function getBuyOrderBook(string symbolName) constant returns (uint[], uint[]) {
        uint8 tokenNameIndex = getSymbolIndexOrThrow(symbolName);
        uint[] memory arrPricesBuy = new uint[](tokens[tokenNameIndex].amountBuyPrices);
        uint[] memory arrVolumesBuy = new uint[](tokens[tokenNameIndex].amountBuyPrices);
        
        uint whilePrice = tokens[tokenNameIndex].lowestBuyPrice;
        uint counter = 0;
        
        if(tokens[tokenNameIndex].curBuyPrice > 0 ){
            while (whilePrice <= tokens[tokenNameIndex].curBuyPrice){
                arrPricesBuy[counter] = whilePrice;
                uint volumeAtPrice = 0;
                uint offers_keys = 0;
                
                offers_keys = tokens[tokenNameIndex].buyBook[whilePrice].offers_keys;
                while(offers_keys <= tokens[tokenNameIndex].buyBook[whilePrice].offers_length) {
                    volumeAtPrice += tokens[tokenNameIndex].buyBook[whilePrice].offers[offers_keys].amount;
                    offers_keys++;
                }
                
                arrVolumesBuy[counter] = volumeAtPrice;
                
                // next whilePrice
                if(whilePrice == tokens[tokenNameIndex].buyBook[whilePrice].higherPrice){
                    break;
                } else {
                    whilePrice = tokens[tokenNameIndex].buyBook[whilePrice].higherPrice;
                }
                counter++;
            }
        }
        return (arrPricesBuy, arrVolumesBuy);
    }


    /////////////////////////////
    // ORDER BOOK - ASK ORDERS //
    /////////////////////////////
    function getSellOrderbook(string symbolName) constant returns(uint[], uint[]) {
        uint8 tokenNameIndex = getSymbolIndexOrThrow(symbolName);
        uint[] memory arrPricesSell = new uint[](tokens[tokenNameIndex].amountSellPrices);
        uint[] memory arrVolumesSell = new uint[](tokens[tokenNameIndex].amountSellPrices);
        uint sellWhilePrice = tokens[tokenNameIndex].curSellPrice; 
        uint sellCounter = 0;
        if(tokens[tokenNameIndex].curSellPrice > 0){
            while (sellWhilePrice <= tokens[tokenNameIndex].highestSellPrice){
                arrPricesSell[sellCounter] = sellWhilePrice;
                uint sellVolumeAtPrice = 0;
                uint sell_offers_key = 0;
                
                sell_offers_key = tokens[tokenNameIndex].sellBook[sellWhilePrice].offers_keys;
                while(sell_offers_key <= tokens[tokenNameIndex].sellBook[sellWhilePrice].offers_length){
                    sellVolumeAtPrice += tokens[tokenNameIndex].sellBook[sellWhilePrice].offers[sell_offers_key].amount;
                    sell_offers_key++;
                }
                
                arrVolumesSell[sellCounter] = sellVolumeAtPrice;
                
                //next whilePrice
                if(tokens[tokenNameIndex].sellBook[sellWhilePrice].higherPrice == 0) {
                    break;
                } else {
                    sellWhilePrice = tokens[tokenNameIndex].sellBook[sellWhilePrice].higherPrice;
                }
                sellCounter++;
            }
        }
        // sell part
        return (arrPricesSell, arrVolumesSell);
    }    



    ////////////////////////////
    // NEW ORDER - BID ORDER //
    ///////////////////////////
    function buyToken(string symbolName, uint priceInWei, uint amount){
        uint tokenNameIndex = getSymbolIndexOrThrow(symbolName);
        uint total_amount_ether_necessary = 0;
        uint total_amount_ether_available = 0;
        
        // if have enouhh ether, we ca, buy that: 
        total_amount_ether_necessary = amount * priceInWei;
        
        // overflow check
        require(total_amount_ether_necessary >= amount);
        require(total_amount_ether_necessary >= priceInWei);
        require(balanceEthForAddress[msg.sender] >= total_amount_ether_necessary);
        require(balanceEthForAddress[msg.sender] - total_amount_ether_necessary >= 0);
        
        // first deduct the amount of ether from our balance
        balanceEthForAddress[msg.sender] -= total_amount_ether_necessary;
        
        if(tokens[tokenNameIndex].amountSellPrices == 0 || tokens[tokenNameIndex].curSellPrice > priceInWei){
            // limit order: we don't enouth amount to fulfill the amount
            
            addBuyOffer(tokenNameIndex, priceInWei, amount, msg.sender);
            
            LimitBuyOrderCreated(tokenNameIndex, msg.sender, amount, priceInWei, tokens[tokenNameIndex].buyBook[priceInWei].offers_length);
        } else {
            revert();
        }
        
    }
    
    

    ///////////////////////////
    // BID LIMIT ORDER LOGIC //
    ///////////////////////////
    function addBuyOffer(uint8 tokenIndex, uint priceInWei, uint amount, address who)  internal {
        tokens[tokenIndex].buyBook[priceInWei].offers_length++;
        tokens[tokenIndex].buyBook[priceInWei].offers[tokens[tokenIndex].buyBook[priceInWei].offers_length] = Offer(amount, who);
        
        if(tokens[tokenIndex].buyBook[priceInWei].offers_length == 1){
            tokens[tokenIndex].buyBook[priceInWei].offers_keys = 1; 
            
            tokens[tokenIndex].amountBuyPrices++;
            
            uint curBuyPrice = tokens[tokenIndex].lowestBuyPrice; 
            if(lowestBuyPrice == 0 || lowestBuyPrice > priceInWei) {
                if(curBuyPrice == 0) {
                    tokens[tokenIndex].curBuyPrice = priceInWei;
                    tokens[tokenIndex].buyBook[priceInWei].higherPrice = priceInWei;
                    tokens[tokenIndex].buyBook[priceInWei].lowerPrice = 0;
                } else {
                    tokens[tokenIndex].buyBook[lowestBuyPrice].lowerPrice = priceInWei;
                    tokens[tokenIndex].buyBook[priceInWei].higherPrice = lowerPrice;
                    tokens[tokenIndex].buyBook[priceInWei].lowerPrice = 0;
                }
                tokens[tokenIndex].lowestBuyPrice = priceInWei;
            } else if(curBuyPrice < priceInWei) {
                tokens[tokenIndex].buyBook[curBuyPrice].higherPrice = priceInWei;
                tokens[tokenIndex].buyBook[priceInWei].higherPrice = priceInWei;
                tokens[tokenIndex].buyBook[priceInWei].lowerPrice = curBuyPrice;
                tokens[tokenIndex].curBuyPrice = priceInWei;
            } else {
                uint buyPrice = tokens[tokenIndex].curBuyPrice; 
                bool weFoundIt = false;
                while(buyPrice > 0 && !weFoundIt){
                    if( buyPrice < priceInWei && 
                        tokens[tokenIndex].buyBook[buyPrice].higherPrice > priceInWei) {
                            tokens[tokenIndex].buyBook[priceInWei].lowerPrice = buyPrice; 
                            tokens[tokenIndex].buyBook[priceInWei].higherPrice = tokens[tokenIndex].buyBook[buyPrice].higherPrice;
                            
                            // set the higherPrice'd order-book entries lowerPrice to the current priceInWei
                            tokens[tokenIndex].buyBook[tokens[tokenIndex].buyBook[buyPrice].higherPrice].lowerPrice = priceInWei;
                            
                            tokens[tokenIndex].buyBook[buyPrice].higherPrice = priceInWei; 
                            
                            weFoundIt = true;
                        }
                    buyPrice = tokens[tokenIndex].buyBook[buyPrice].lowerPrice;
                }
            }
        }
    }


    ////////////////////////////
    // NEW ORDER - ASK ORDER //
    ///////////////////////////
    
    function sellToken(string symbolName, uint priceInWei, uint amount) {
        uint8 tokenNameIndex = getSymbolIndexOrThrow(symbolName); 
        uint total_amount_ether_necessary = 0;
        uint total_amount_ether_available = 0;
        
        if(tokens[tokenNameIndex].amountBuyPrices == 0 || tokens[tokenNameIndex].curBuyPrice < priceInWei){
            total_amount_ether_necessary = amount * priceInWei;
            
            //overflow check
            require(total_amount_ether_necessary >= amount);
            require(total_amount_ether_necessary >= priceInWei);
            require(tokenBalanceForAddress[msg.sender][tokenNameIndex] >= amount);
            require(tokenBalanceForAddress[msg.sender][tokenNameIndex] - amount >= 0);
            require(balanceEthForAddress[msg.sender] + total_amount_ether_necessary >= balanceEthForAddress[msg.sender]);
            
            // actually substract  the amount of tokens it then 
            tokenBalanceForAddress[msg.sender][tokenNameIndex] -= amount; 
            
            // limit order: we don't have enough offers to fullfil the amount
            
        }
    }    



    ///////////////////////////
    // ASK LIMIT ORDER LOGIC //
    ///////////////////////////
    

    //////////////////////////////
    // CANCEL LIMIT ORDER LOGIC //
    //////////////////////////////
   




 ////////////////////////////////
    // STRING COMPARISON FUNCTION //
    ////////////////////////////////
    function stringsEqual(string storage _a, string memory _b) internal returns (bool) {
        bytes storage a = bytes(_a);
        bytes memory b = bytes(_b);
        if (a.length != b.length) {
            return false;
        }
        // @todo unroll this loop
        for (uint i = 0; i < a.length; i ++) {
            if (a[i] != b[i]) {
                return false;
            }
        }
        return true;
    }



}

FixedSupplyToken.sol

pragma solidity ^0.4.8;

// ----------------------------------------------------------------------------------------------
// Sample fixed supply token contract
// Enjoy. (c) BokkyPooBah 2017. The MIT Licence.
// ----------------------------------------------------------------------------------------------


// ERC Token Standard #20 Interface
// https://github.com/ethereum/EIPs/issues/20
contract ERC20Interface {
    // Get the total token supply
    function totalSupply() constant returns (uint256 totalSupply);

    // Get the account balance of another account with address _owner
    function balanceOf(address _owner) constant returns (uint256 balance);

    // Send _value amount of tokens to address _to
    function transfer(address _to, uint256 _value) returns (bool success);

    // Send _value amount of tokens from address _from to address _to
    function transferFrom(address _from, address _to, uint256 _value) returns (bool success);

    // Allow _spender to withdraw from your account, multiple times, up to the _value amount.
    // If this function is called again it overwrites the current allowance with _value.
    // this function is required for some DEX functionality
    function approve(address _spender, uint256 _value) returns (bool success);

    // Returns the amount which _spender is still allowed to withdraw from _owner
    function allowance(address _owner, address _spender) constant returns (uint256 remaining);

    // Triggered when tokens are transferred.
    event Transfer(address indexed _from, address indexed _to, uint256 _value);

    // Triggered whenever approve(address _spender, uint256 _value) is called.
    event Approval(address indexed _owner, address indexed _spender, uint256 _value);
}


contract FixedSupplyToken is ERC20Interface {
    string public constant symbol = "FIXED";
    string public constant name = "Example Fixed Supply Token";
    uint8 public constant decimals = 0;
    uint256 _totalSupply = 1000000;

    // Owner of this contract
    address public owner;

    // Balances for each account
    mapping (address => uint256) balances;

    // Owner of account approves the transfer of an amount to another account
    mapping (address => mapping (address => uint256)) allowed;

    // Functions with this modifier can only be executed by the owner
    modifier onlyOwner() {
        if (msg.sender != owner) {
            throw;
        }
        _;
    }

    // Constructor
    function FixedSupplyToken() {
        owner = msg.sender;
        balances[owner] = _totalSupply;
    }

    function totalSupply() constant returns (uint256 totalSupply) {
        totalSupply = _totalSupply;
    }

    // What is the balance of a particular account?
    function balanceOf(address _owner) constant returns (uint256 balance) {
        return balances[_owner];
    }

    // Transfer the balance from owner's account to another account
    function transfer(address _to, uint256 _amount) returns (bool success) {
        if (balances[msg.sender] >= _amount
        && _amount > 0
        && balances[_to] + _amount > balances[_to]) {
            balances[msg.sender] -= _amount;
            balances[_to] += _amount;
            Transfer(msg.sender, _to, _amount);
            return true;
        }
        else {
            return false;
        }
    }

    // Send _value amount of tokens from address _from to address _to
    // The transferFrom method is used for a withdraw workflow, allowing contracts to send
    // tokens on your behalf, for example to "deposit" to a contract address and/or to charge
    // fees in sub-currencies; the command should fail unless the _from account has
    // deliberately authorized the sender of the message via some mechanism; we propose
    // these standardized APIs for approval:
    function transferFrom(
    address _from,
    address _to,
    uint256 _amount
    ) returns (bool success) {
        if (balances[_from] >= _amount
        && allowed[_from][msg.sender] >= _amount
        && _amount > 0
        && balances[_to] + _amount > balances[_to]) {
            balances[_from] -= _amount;
            allowed[_from][msg.sender] -= _amount;
            balances[_to] += _amount;
            Transfer(_from, _to, _amount);
            return true;
        }
        else {
            return false;
        }
    }


    // Allow _spender to withdraw from your account, multiple times, up to the _value amount.
    // If this function is called again it overwrites the current allowance with _value.
    function approve(address _spender, uint256 _amount) returns (bool success) {
        allowed[msg.sender][_spender] = _amount;
        Approval(msg.sender, _spender, _amount);
        return true;
    }

    function allowance(address _owner, address _spender) constant returns (uint256 remaining) {
        return allowed[_owner][_spender];
    }

}

JobList.sol

pragma solidity ^0.4.24;

contract JobList {

  struct Job {
    uint256 jobSalary;
    string jobTitle;
    string jobDescription;
    bool salaryDelivred;
    bool active;
    bool inProgress;
    address workerAddress;
    address creatorAddress;

  }

  Job[] jobArray;

  uint jobCount = 0;
  uint finishedJobCount = 0;
  uint workInprogressCount = 0;

  mapping (uint => Job) jobs;
  mapping (address => uint) myWorkInprogress;

  event LogAddJob(string title, string desc, uint salary);
  event LogPayFreelancer(uint _index, address indexed creatorAddress, address indexed workerAddress, uint salary);
  event LogFreelancerDoneJob(uint index, address indexed workerAddress);
  event LogFreelancerTakeJob(uint index, address indexed workerAddress);

  function addJob(
    string _jobTitle,
    string _jobDescription,
    uint256 _jobSalary
    ) public {
        require(_jobSalary > 0);
        require(bytes(_jobTitle).length > 0);
        require(bytes(_jobDescription).length > 0);

      Job memory _job = jobs[jobCount];

      _job.workerAddress = 0x0;
      _job.jobSalary += (_jobSalary * 10e18);
      _job.jobTitle = _jobTitle;
      _job.jobDescription = _jobDescription;
      _job.active = true;
      _job.inProgress = false;
      _job.creatorAddress = msg.sender;
      _job.salaryDelivred = false;

      jobArray.push(_job);
      jobCount++;

      emit LogAddJob(_job.jobTitle, _job.jobDescription, _job.jobSalary);
  }

  function getTotalJobNumber() view public returns(uint) {
    return jobCount;
  }

  function getJobByIndex(uint _index) view public returns(address, uint, string, string, bool, bool, bool) {
    return (
      jobs[_index].workerAddress,
      jobs[_index].jobSalary,
      jobs[_index].jobTitle,
      jobs[_index].jobDescription,
      jobs[_index].active,
      jobs[_index].inProgress,
      jobs[_index].salaryDelivred
      );
  }

  function doThisJob(uint _index) public {
    require(jobs[_index].active == true);
    jobs[_index].workerAddress = msg.sender;
    jobs[_index].inProgress = true;

    workInprogressCount++;

    emit LogFreelancerTakeJob(_index, jobs[_index].workerAddress);
  }

  function jobDone(uint _index) public {
    require(jobs[_index].workerAddress == msg.sender);

    jobs[_index].inProgress = false;
    jobs[_index].active = false;

    emit LogFreelancerDoneJob(_index, jobs[_index].workerAddress);
  }

  function cancelJob(uint _index) public {
    require(jobs[_index].creatorAddress == msg.sender && jobs[_index].inProgress == false);

    jobs[_index].active = false;
  }

  function payTheFreelancer(uint _index) public payable{
    require(jobs[_index].creatorAddress == msg.sender);
    require(jobs[_index].inProgress == false && jobs[_index].active == false);

    address dest = jobs[_index].workerAddress;

    require(jobs[_index].jobSalary <= msg.value * 1 ether);

    jobs[_index].workerAddress.transfer(msg.value);
    jobs[_index].salaryDelivred = true;

    emit LogPayFreelancer(_index, jobs[_index].creatorAddress, dest, jobs[_index].jobSalary);

  }
}

Migration.sol

pragma solidity ^0.4.4;

contract Migrations {
  address public owner;
  uint public last_completed_migration;

  modifier restricted() {
    if (msg.sender == owner) _;
  }

  function Migrations() {
    owner = msg.sender;
  }

  function setCompleted(uint completed) restricted {
    last_completed_migration = completed;
  }

  function upgrade(address new_address) restricted {
    Migrations upgraded = Migrations(new_address);
    upgraded.setCompleted(last_completed_migration);
  }
}

Owned.sol

pragma solidity ^0.4.0;

contract owned {
    address owner;

    modifier onlyOwner() {
        if (msg.sender == owner) {
            _;
        }
    }

    function owned() {
        owner = msg.sender;
    }
}