// Contract: ReitBZ
// Target function: function _registerBurn(address from, uint256 amount) public onlyToken
 Emits an Approval event.
     * @param spender The address which will spend the funds.
     * @param subtractedValue The amount of tokens to decrease the allowance by.
     */
    function decreaseAllowance(address spender, uint256 subtractedValue) public returns (bool) {
        require(spender != address(0));

        _allowed[msg.sender][spender] = _allowed[msg.sender][spender].sub(subtractedValue);
        emit Approval(msg.sender, spender, _allowed[msg.sender][spender]);
        return true;
    }

    /**
    * @dev Transfer token for a specified addresses
    * @param from The address to transfer from.
    * @param to The address to transfer to.
    * @param value The amount to be transferred.
    */
    function _transfer(address from, address to, uint256 value) internal {
        require(to != address(0));

        _balances[from] = _balances[from].sub(value);
        _balances[to] = _balances[to].add(value);
        emit Transfer(from, to, value);
    }

    /**
     * @dev Internal function that mints an amount of the token and assigns it to
     * an account. This encapsulates the modification of balances such that the
     * proper events are emitted.
     * @param account The account that will receive the created tokens.
     * @param value The amount that will be created.
     */
    function _mint(address account, uint256 value) internal {
        require(account != address(0));

        _totalSupply = _totalSupply.add(value);
        _balances[account] = _balances[account].add(value);
        emit Transfer(address(0), account, value);
    }

    /**
     * @dev Internal function that burns an amount of the token of a given
     * account.
     * @param account The account whose tokens will be burnt.
     * @param value The amount that will be burnt.
     */
    function _burn(address account, uint256 value) internal {
        require(account != address(0));

        _totalSupply = _totalSupply.sub(value);
        _balances[account] = _balances[account].sub(value);
        emit Transfer(account, address(0), value);
    }

    /**
     * @dev Internal function that burns an amount of the token of a given
     * account, deducting from the sender's allowance for said account. Uses the
     * internal burn function.
     * Emits an Approval event (reflecting the reduced allowance).
     * @param account The account whose tokens will be burnt.
     * @param value The amount that will be burnt.
     */
    function _burnFrom(address account, uint256 value) internal {
        _allowed[account][msg.sender] = _allowed[account][msg.sender].sub(value);
        _burn(account, value);
        emit Approval(account, msg.sender, _allowed[account][msg.sender]);
    }
}




contract MinterRole {
    using Roles for Roles.Role;

    event MinterAdded(address indexed account);
    event MinterRemoved(address indexed account);

    Roles.Role private _minters;

    constructor () internal {
        _addMinter(msg.sender);
    }

    modifier onlyMinter() {
        require(isMinter(msg.sender));
        _;
    }

    function isMinter(address account) public view returns (bool) {
        return _minters.has(account);
    }

    function addMinter(address account) public onlyMinter {
        _addMinter(account);
    }

    function renounceMinter() public {
        _removeMinter(msg.sender);
    }

    function _addMinter(address account) internal {
        _minters.add(account);
        emit MinterAdded(account);
    }

    function _removeMinter(address account) internal {
        _minters.remove(account);
        emit MinterRemoved(account);
    }
}




/**
 * @title Ownable
 * @dev The Ownable contract has an owner address, and provides basic authorization control
 * functions, this simplifies the implementation of "user permissions".
 */
contract Ownable {
    address private _owner;

    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);

    /**
     * @dev The Ownable constructor sets the original `owner` of the contract to the sender
     * account.
     */
    constructor () internal {
        _owner = msg.sender;
        emit OwnershipTransferred(address(0), _owner);
    }

    /**
     * @return the address of the owner.
     */
    function owner() public view returns (address) {
        return _owner;
    }

    /**
     * @dev Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        require(isOwner());
        _;
    }

    /**
     * @return true if `msg.sender` is the owner of the contract.
     */
    function isOwner() public view returns (bool) {
        return msg.sender == _owner;
    }

    /**
     * @dev Allows the current owner to relinquish control of the contract.
     * @notice Renouncing to ownership will leave the contract without an owner.
     * It will not be possible to call the functions with the `onlyOwner`
     * modifier anymore.
     */
    function renounceOwnership() public onlyOwner {
        emit OwnershipTransferred(_owner, address(0));
        _owner = address(0);
    }

    /**
     * @dev Allows the current owner to transfer control of the contract to a newOwner.
     * @param newOwner The address to transfer ownership to.
     */
    function transferOwnership(address newOwner) public onlyOwner {
        _transferOwnership(newOwner);
    }

    /**
     * @dev Transfers control of the contract to a newOwner.
     * @param newOwner The address to transfer ownership to.
     */
    function _transferOwnership(address newOwner) internal {
        require(newOwner != address(0));
        emit OwnershipTransferred(_owner, newOwner);
        _owner = newOwner;
    }
}





/**
 * @title Burnable Token
 * @dev Token that can be irreversibly burned (destroyed).
 */
contract ERC20Burnable is ERC20 {
    /**
     * @dev Burns a specific amount of tokens.
     * @param value The amount of token to be burned.
     */
    function burn(uint256 value) public {
        _burn(msg.sender, value);
    }

    /**
     * @dev Burns a specific amount of tokens from the target address and decrements allowance
     * @param from address The address which you want to send tokens from
     * @param value uint256 The amount of token to be burned
     */
    function burnFrom(address from, uint256 value) public {
        _burnFrom(from, value);
    }
}






/**
 * @title ERC20Mintable
 * @dev ERC20 minting logic
 */
contract ERC20Mintable is ERC20, MinterRole {
    /**
     * @dev Function to mint tokens
     * @param to The address that will receive the minted tokens.
     * @param value The amount of tokens to mint.
     * @return A boolean that indicates if the operation was successful.
     */
    function mint(address to, uint256 value) public onlyMinter returns (bool) {
        _mint(to, value);
        return true;
    }
}








/**
 * @title Pausable
 * @dev Base contract which allows children to implement an emergency stop mechanism.
 */
contract Pausable is PauserRole {
    event Paused(address account);
    event Unpaused(address account);

    bool private _paused;

    constructor () internal {
        _paused = false;
    }

    /**
     * @return true if the contract is paused, false otherwise.
     */
    function paused() public view returns (bool) {
        return _paused;
    }

    /**
     * @dev Modifier to make a function callable only when the contract is not paused.
     */
    modifier whenNotPaused() {
        require(!_paused);
        _;
    }

    /**
     * @dev Modifier to make a function callable only when the contract is paused.
     */
    modifier whenPaused() {
        require(_paused);
        _;
    }

    /**
     * @dev called by the owner to pause, triggers stopped state
     */
    function pause() public onlyPauser whenNotPaused {
        _paused = true;
        emit Paused(msg.sender);
    }

    /**
     * @dev called by the owner to unpause, returns to normal state
     */
    function unpause() public onlyPauser whenPaused {
        _paused = false;
        emit Unpaused(msg.sender);
    }
}


/**
 * @title Pausable token
 * @dev ERC20 modified with pausable transfers.
 **/
contract ERC20Pausable is ERC20, Pausable {
    function transfer(address to, uint256 value) public whenNotPaused returns (bool) {
        return super.transfer(to, value);
    }

    function transferFrom(address from, address to, uint256 value) public whenNotPaused returns (bool) {
        return super.transferFrom(from, to, value);
    }

    function approve(address spender, uint256 value) public whenNotPaused returns (bool) {
        return super.approve(spender, value);
    }

    function increaseAllowance(address spender, uint addedValue) public whenNotPaused returns (bool success) {
        return super.increaseAllowance(spender, addedValue);
    }

    function decreaseAllowance(address spender, uint subtractedValue) public whenNotPaused returns (bool success) {
        return super.decreaseAllowance(spender, subtractedValue);
    }
}





/**
 * @title ERC20Detailed token
 * @dev The decimals are only for visualization purposes.
 * All the operations are done using the smallest and indivisible token unit,
 * just as on Ethereum all the operations are done in wei.
 */
contract ERC20Detailed is IERC20 {
    string private _name;
    string private _symbol;
    uint8 private _decimals;

    constructor (string memory name, string memory symbol, uint8 decimals) public {
        _name = name;
        _symbol = symbol;
        _decimals = decimals;
    }

    /**
     * @return the name of the token.
     */
    function name() public view returns (string memory) {
        return _name;
    }

    /**
     * @return the symbol of the token.
     */
    function symbol() public view returns (string memory) {
        return _symbol;
    }

    /**
     * @return the number of decimals of the token.
     */
    function decimals() public view returns (uint8) {
        return _decimals;
    }
}





contract TokenWhitelist is Ownable {

    mapping(address => bool) private whitelist;

    event Whitelisted(address indexed wallet);
    event Dewhitelisted(address indexed wallet);

    function enableWallet(address _wallet) public onlyOwner {
        require(_wallet != address(0), "Invalid wallet");
        whitelist[_wallet] = true;
        emit Whitelisted(_wallet);
    }
    
    function enableWalletBatch(address[] memory _wallets) public onlyOwner {
        for (uint256 i = 0; i < _wallets.length; i++) {
            enableWallet(_wallets[i]);
        }
    }


    function disableWallet(address _wallet) public onlyOwner {
        require(_wallet != address(0), "Invalid wallet");
        whitelist[_wallet] = false;
        emit Dewhitelisted(_wallet);
    }

    
    function disableWalletBatch(address[] memory _wallets) public onlyOwner {
        for (uint256 i = 0; i < _wallets.length; i++) {
            disableWallet(_wallets[i]);
        }
    }
    
    function checkWhitelisted(address _wallet) public view returns (bool){
        return whitelist[_wallet];
    }
    
}
















contract TrustedRole is Ownable {
    using Roles for Roles.Role;

    event TrustedAdded(address indexed account);
    event TrustedRemoved(address indexed account);

    Roles.Role private trusted;

    constructor() internal {
        _addTrusted(msg.sender);
    }

    modifier onlyOwnerOrTrusted() {
        require(isOwner() || isTrusted(msg.sender), "Only owner or trusted allowed");
        _;
    }

    modifier onlyTrusted() {
        require(isTrusted(msg.sender), "Only trusted allowed");
        _;
    }

    function isTrusted(address account) public view returns (bool) {
        return trusted.has(account);
    }

    function addTrusted(address account) public onlyOwner {
        _addTrusted(account);
    }

    function removeTrusted(address account) public onlyOwner {
        _removeTrusted(account);
    }

    function _addTrusted(address account) internal {
        trusted.add(account);
        emit TrustedAdded(account);
    }

    function _removeTrusted(address account) internal {
        trusted.remove(account);
        emit TrustedRemoved(account);
    }
}


/**
 * @title MultiTokenDividend
 *
 * Based on https://medium.com/%40weka/dividend-bearing-tokens-on-ethereum-42d01c710657
 * Distributes dividends on multiple currencies: ETH and ERC20
 */
contract MultiTokenDividend is Ownable, TrustedRole {
    using SafeMath for uint256;
    using SafeERC20 for IERC20;

    // Stores each account preferred payment method and balance
    struct Account {
        address tokenAddress;
        uint256 amount;
        uint256 lastTotalDividendPoints;
    }
    mapping(address => Account) public accounts;

    // Stores information about each payment method
    struct Dividend {
        uint256 totalDividendPoints;
        uint256 unclaimedDividends;
        uint256 totalSupply;
    }
    mapping(address => Dividend) public tokenDividends;

    // Main token for calculation of dividends
    ERC20Detailed private _sharesToken;

    // Constant to allow division by totalSupply (from the article)
    uint256 private X;

    // Disbursement failure for tracking
    event TransferFailure(address indexed beneficiary);

    constructor(ERC20Detailed token, uint256 const) public {
        _sharesToken = token;
        X = const;
    }

    // Access
    modifier onlyToken() {
        require(msg.sender == address(_sharesToken), "Only the token allowed");
        _;
    }

    // Receive and collect funds
    function() external payable {}
    function collect(address tokenAddress) public onlyOwner {
        if (tokenAddress == address(0)) {
            address(uint160(owner())).transfer(address(this).balance);
        }
        else {
            IERC20 token = IERC20(tokenAddress);
            token.safeTransfer(owner(), token.balanceOf(address(this)));
        }
    }

    function setPaymentMethod(address beneficiary, address tokenAddress) public onlyOwnerOrTrusted {
        // Ensure he doesn't lose his unclaimed dividends
        updateAccount(beneficiary);
        require(accounts[beneficiary].amount == 0, "Withdraw the balance before changing payout token");

        // Set the new payment method
        address oldToken = accounts[beneficiary].tokenAddress;
        accounts[beneficiary].tokenAddress = tokenAddress;
        accounts[beneficiary].lastTotalDividendPoints = tokenDividends[tokenAddress].totalDividendPoints;
        
        // Move his pool of tokens to another payment method
        uint256 beneficiaryShares = _sharesToken.balanceOf(beneficiary);
        tokenDividends[oldToken].totalSupply = tokenDividends[oldToken].totalSupply.sub(beneficiaryShares);
        tokenDividends[tokenAddress].totalSupply = tokenDividends[tokenAddress].totalSupply.add(beneficiaryShares);
    }

    function dividendsOwing(address beneficiary) internal view returns(uint256) {
        Account storage account = accounts[beneficiary];
        uint256 newDividendPoints = tokenDividends[account.tokenAddress].totalDividendPoints.sub(account.lastTotalDividendPoints);
        return _sharesToken.balanceOf(beneficiary).mul(newDividendPoints).div(X);
    }

    function updateAccount(address account) public onlyOwnerOrTrusted {
        _updateAccount(account);
    }

    function _updateAccount(address account) internal {
        uint256 owing = dividendsOwing(account);
        Dividend storage dividend = tokenDividends[accounts[account].tokenAddress];
        if (owing > 0) {
            dividend.unclaimedDividends = dividend.unclaimedDividends.sub(owing);
            accounts[account].amount = accounts[account].amount.add(owing);
        }
        // Prevent new account holders to claim past dividends
        if (accounts[account].lastTotalDividendPoints != dividend.totalDividendPoints) {
            accounts[account].lastTotalDividendPoints = dividend.totalDividendPoints;
        }
    }

    // Register dividends for these payment methods
    function addDividends(address[] memory tokens) public onlyOwner {
        for (uint256 i = 0; i < tokens.length; i++) {
            address token = tokens[i];
            uint256 tokenAmount = 0;
            
            // Get the total amount to distribute
            if (token == address(0)) {
                // ETH
                tokenAmount = address(this).balance;
            }
            else {
                // ERC20
                tokenAmount = IERC20(token).balanceOf(address(this));
            }

            Dividend storage dividend = tokenDividends[token];

            // Subtract unclaimed tokens
            if (tokenAmount > dividend.unclaimedDividends) {
                tokenAmount = tokenAmount - dividend.unclaimedDividends;
                dividend.totalDividendPoints = dividend.totalDividendPoints.add(
                    tokenAmount.mul(X).div(dividend.totalSupply)
                );
                dividend.unclaimedDividends = dividend.unclaimedDividends.add(tokenAmount);
            }
        }
    }

    // Send the dividends to their accounts
    // Iterate offchain to prevent hitting the gas limit
    function disburse(address payable[] calldata beneficiaries) external onlyOwner {
        for (uint256 i = 0; i < beneficiaries.length; i++) {
            address payable acc = beneficiaries[i];
            updateAccount(acc);

            bool success = _disburse(acc);
            if (!success) {
                emit TransferFailure(acc);
            }
        }
    }

    function withdraw() public {
        _updateAccount(msg.sender);
        require(_disburse(msg.sender), "Failed to transfer ETH");
    }

    function _disburse(address payable beneficiary) internal returns (bool) {
        Account storage account = accounts[beneficiary];
        uint256 amount = account.amount;
        if (amount == 0) return true;
        
        // Set to 0 before transfering
        account.amount = 0;

        if (account.tokenAddress == address(0)) {
            // ETH disbursement
            bool success = beneficiary.send(amount);
            if (!success) {
                account.amount = amount;
            }
            return success;
        }
        else {
            // ERC20 disbursement
            IERC20 token = IERC20(account.tokenAddress);
            token.safeTransfer(beneficiary, amount);
            return true;
        }
    }