contract KDO is Ownable, ERC20Detailed, ERC20Mintable {
  struct Ticket {
    // Type of the ticket
    string tType;

    // Creation date and expiration date
    uint createdAt;
    uint expireAt;

    address contractor;

    // The ticket has published a review
    bool hasReviewed;
  }

  // A contractor is someone that will be credited by tickets (clients)
  struct Contractor {
    // Its reviews
    mapping (uint => uint) reviews;

    // Total of tickets
    uint256 nbCredittedTickets;

    // Total of debitted tokens
    uint256 debittedBalance;
  }

  // Commission regarding the review average, the index is about the rating value
  // the value is the commission in %
  uint8[5] public commissions;

  mapping (address => Ticket) public tickets;

  // A contractor is a person who can consume ticketTypes and be credited for
  mapping (address => Contractor) public contractors;

  event CreditEvt(address ticket, address contractor, string tType, uint256 date);
  event DebitEvt(address contractor, uint256 amount, uint256 commission, uint256 date);
  event ReviewEvt(address reviewer, address contractor, uint rate, uint256 date);
  event CommissionsChangeEvt(uint8[5] commissions, uint256 date);

  mapping (uint256 => string) public ticketTypes;

  // Minimum base value for tickets 150000 Gwei
  uint256 constant public MIN_TICKET_BASE_VALUE = 150000000000000;

  // Min and Max commission in %
  uint256 constant public MIN_COMMISSION = 8;
  uint256 constant public MAX_COMMISSION = 30;

  // Value to transfer to tickets when allocated
  uint256 public ticketBaseValue;

  // .0% of 10e18 (1 = 0.1%, 10 = 1%)
  uint256 public ticketCostBase;

  address private _businessOwner;

  constructor(uint8[5] _commissions, address __businessOwner)
    ERC20Detailed("KDO Coin", "KDO", 0)
    public
  {
    ticketBaseValue = MIN_TICKET_BASE_VALUE;
    ticketCostBase = 3;

    updateCommissions(_commissions);

    _businessOwner = __businessOwner;
  }

  // Only listed tickets
  modifier onlyExistingTicketAmount(uint256 _amount) {
    require(bytes(ticketTypes[_amount]).length > 0, '{error: UNKNOWN_TICKET}');
    _;
  }

  // Update the ticket base cost for following market value in case of crash or
  // pump
  // @param _value new ticket base cost
  function updateTicketCostBase(uint256 _value) public
    onlyOwner()
  {
    require(_value > 0 && _value <= 500, '{error: BAD_VALUE, message: "Should be > 0 and <= 500"}');
    ticketCostBase = _value;
  }

  // Update the ticket base value
  // a ticket value is the amount of ether allowed to the ticket in order to
  // be used
  // @param _value is the base value change, in wei
  function updateTicketBaseValue(uint256 _value) public
    onlyOwner()
  {
    // Cant put a value below the minimal value
    require(_value >= MIN_TICKET_BASE_VALUE, '{error: BAD_VALUE, message: "Value too low"}');
    ticketBaseValue = _value;
  }

  // Update the commissions
  // @param _c are the new commissions
  function updateCommissions(uint8[5] _c) public
    onlyOwner()
  {
    for (uint i = 0; i <= 4; i++) {
        require(_c[i] <= MAX_COMMISSION && _c[i] >= MIN_COMMISSION, '{error: BAD_VALUE, message: "A commission it too low or too high"}');
    }
    commissions = _c;
    emit CommissionsChangeEvt(_c, now);
  }

  // Add a new ticket type
  // Can update an old ticket type, for instance :
  // ticketTypes[99] = "bronze"
  // addTicketType(99, "wood")
  // ticketTypes[99] = "wood"
  // ticket 99 has been updated from "bronze" to "wood"
  // @param _amount is the ticket amount to update
  // @param _key is the key to attribute to the amount
  function addTicketType(uint256 _amount, string _key) public
    onlyOwner()
  {
    ticketTypes[_amount] = _key;
  }

  // Create a ticket using KDO tokens
  // @param _to ticket to create
  // @param _KDOAmount amount to allocate to the ticket
  function allocateNewTicketWithKDO(address _to, uint256 _KDOAmount)
    public
    payable
    onlyExistingTicketAmount(_KDOAmount)
    returns (bool success)
  {
      require(msg.value >= ticketBaseValue, '{error: BAD_VALUE, message: "Value too low"}');

      _to.transfer(ticketBaseValue);

      super.transfer(_to, _KDOAmount);

      _createTicket(_to, _KDOAmount);

      return true;
  }

  // Allocates a ticket to an address and create tokens (accordingly to the value of the allocated ticket)
  // @param _to ticket to create
  // @param _amount amount to allocate to the ticket
  function allocateNewTicket(address _to, uint256 _amount)
    public
    payable
    onlyExistingTicketAmount(_amount)
    returns (bool success)
  {
    uint256 costInWei = costOfTicket(_amount);
    require(msg.value == costInWei, '{error: BAD_VALUE, message: "Value should be equal to the cost of the ticket"}');

    // Give minimal WEI value to a ticket
    _to.transfer(ticketBaseValue);

    // Price of the ticket transfered to the business owner address
    _businessOwner.transfer(costInWei - ticketBaseValue);

    super.mint(_to, _amount);

    _createTicket(_to, _amount);

    return true;
  }

  // Checks if an address can handle the ticket type
  // @param _ticketAddr tocket to check
  function isTicketValid(address _ticketAddr)
    public
    view
    returns (bool valid)
  {
    if (tickets[_ticketAddr].contractor == 0x0 && now < tickets[_ticketAddr].expireAt) {
      return true;
    }
    return false;
  }

  // A ticket credit the contractor balance
  // It triggers Consume event for logs
  // @param _contractor contractor to credit
  // @param _amount amount that will be creditted
  function creditContractor(address _contractor, uint256 amount)
    public
    onlyExistingTicketAmount(amount)
    returns (bool success)
  {
    require(isTicketValid(msg.sender), '{error: INVALID_TICKET}');

    super.transfer(_contractor, amount);

    contractors[_contractor].nbCredittedTickets += 1;

    tickets[msg.sender].contractor = _contractor;

    emit CreditEvt(msg.sender, _contractor, tickets[msg.sender].tType, now);

    return true;
  }

  // Publish a review and rate the ticket's contractor (only consumed tickets can
  // perform this action)
  // @param _reviewRate rating of the review
  function publishReview(uint _reviewRate) public {
    // Only ticket that hasn't published any review and that has been consumed
    require(!tickets[msg.sender].hasReviewed && tickets[msg.sender].contractor != 0x0, '{error: INVALID_TICKET}');

    // Only between 0 and 5
    require(_reviewRate >= 0 && _reviewRate <= 5, '{error: INVALID_RATE, message: "A rate should be between 0 and 5 included"}');

    // Add the review to the contractor of the ticket
    contractors[tickets[msg.sender].contractor].reviews[_reviewRate] += 1;

    tickets[msg.sender].hasReviewed = true;

    emit ReviewEvt(msg.sender, tickets[msg.sender].contractor, _reviewRate, now);
  }

  // Calculate the average rating of a contractor
  // @param _address contractor address
  function reviewAverageOfContractor(address _address) public view returns (uint avg) {
    // Percentage threshold
    uint decreaseThreshold = 60;

    // Apply a penalty of -1 for reviews = 0
    int totReviews = int(contractors[_address].reviews[0]) * -1;

    uint nbReviews = contractors[_address].reviews[0];

    for (uint i = 1; i <= 5; i++) {
      totReviews += int(contractors[_address].reviews[i] * i);
      nbReviews += contractors[_address].reviews[i];
    }

    if (nbReviews == 0) {
      return 250;
    }

    // Too much penalties leads to 0, then force it to be 0, the average
    // can't be negative
    if (totReviews < 0) {
      totReviews = 0;
    }

    uint percReviewsTickets = (nbReviews * 100 / contractors[_address].nbCredittedTickets);

    avg = (uint(totReviews) * 100) / nbReviews;

    if (percReviewsTickets >= decreaseThreshold) {
      return avg;
    }

    // A rate < 60% on the number of reviews will decrease the rating average of
    // the difference between the threshold and the % of reviews
    // for instance a percent reviews of 50% will decrease the rating average
    // of 10% (60% - 50%)
    // This is to avoid abuse of the system, without this mecanism a contractor
    // could stay with a average of 500 (the max) regardless of the number
    // of ticket he used.
    uint decreasePercent = decreaseThreshold - percReviewsTickets;

    return avg - (avg / decreasePercent);
  }

  // Returns the commission for the contractor
  // @param _address contractor address
  function commissionForContractor(address _address) public view returns (uint8 c) {
    return commissionForReviewAverageOf(reviewAverageOfContractor(_address));
  }

  // Returns the info of a ticket
  // @param _address ticket address
  function infoOfTicket(address _address) public view returns (uint256 balance, string tType, bool isValid, uint createdAt, uint expireAt, address contractor, bool hasReviewed) {
    return (super.balanceOf(_address), tickets[_address].tType, isTicketValid(_address), tickets[_address].createdAt, tickets[_address].expireAt, tickets[_address].contractor, tickets[_address].hasReviewed);
  }

  // Returns the contractor info
  // @param _address contractor address
  function infoOfContractor(address _address) public view returns(uint256 balance, uint256 debittedBalance, uint256 nbReviews, uint256 nbCredittedTickets, uint256 avg) {
    for (uint i = 0; i <= 5; i++) {
      nbReviews += contractors[_address].reviews[i];
    }

    return (super.balanceOf(_address), contractors[_address].debittedBalance, nbReviews, contractors[_address].nbCredittedTickets, reviewAverageOfContractor(_address));
  }

  // Transfers contractors tokens to the owner
  // It triggers Debit event
  // @param _amount amount to debit
  function debit(uint256 _amount) public {
    super.transfer(super.owner(), _amount);

    emit DebitEvt(msg.sender, _amount, commissionForContractor(msg.sender), now);
  }

  // Returns the cost of a ticket regarding its amount
  // Returned value is represented in Wei
  // @param _amount amount of the ticket
  function costOfTicket(uint256 _amount) public view returns(uint256 cost) {
    return (_amount * (ticketCostBase * 1000000000000000)) + ticketBaseValue;
  }

  // Calculate the commission regarding the rating (review average)
  // Example with a commissions = [30, 30, 30, 25, 20]
  // [0,3[ = 30% (DefaultCommission)
  // [3,4[ = 25%
  // [4,5[ = 20%
  // A rating average of 3.8 = 25% of commission
  // @param _avg commission average
  function commissionForReviewAverageOf(uint _avg) public view returns (uint8 c) {
    if (_avg >= 500) {
      return commissions[4];
    }

    for (uint i = 0; i < 5; i++) {
      if (_avg <= i * 100 || _avg < (i + 1) * 100) {
        return commissions[i];
      }
    }

    // Default commission when there is something wrong
    return commissions[0];
  }

  function _createTicket(address _address, uint256 _amount) private {
    tickets[_address] = Ticket({
      tType: ticketTypes[_amount],
      createdAt: now,
      expireAt: now + 2 * 365 days,
      contractor: 0x0,
      hasReviewed: false
    });
  }
}
function infoOfTicket(address _address) public view returns (uint256 balance, string tType, bool isValid, uint createdAt, uint expireAt, address contractor, bool hasReviewed) {
  return (super.balanceOf(_address), tickets[_address].tType, isTicketValid(_address), tickets[_address].createdAt, tickets[_address].expireAt, tickets[_address].contractor, tickets[_address].hasReviewed);
}

// Returns the info of a ticket
// @param _address ticket address