pragma solidity ^0.4.15;

// File: contracts/math/SafeMath.sol

/**
 * @title SafeMath
 * @dev Math operations with safety checks that throw on error
 * Based on OpenZeppelin
 */
library SafeMath {
  function mul(uint256 a, uint256 b) internal constant returns (uint256) {
    uint256 c = a * b;
    assert(a == 0 || c / a == b);
    return c;
  }

  function div(uint256 a, uint256 b) internal constant returns (uint256) {
    // assert(b > 0); // Solidity automatically throws 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;
  }

  function sub(uint256 a, uint256 b) internal constant returns (uint256) {
    assert(b <= a);
    return a - b;
  }

  function add(uint256 a, uint256 b) internal constant returns (uint256) {
    uint256 c = a + b;
    assert(c >= a);
    return c;
  }
}

// File: contracts/token/ERC20Basic.sol

/**
 * @title ERC20Basic
 * @dev Simpler version of ERC20 interface
 * @dev see https://github.com/ethereum/EIPs/issues/179
 *
 * Based on OpenZeppelin
 */
contract ERC20Basic {
    uint256 public totalSupply;
    function balanceOf(address who) public constant returns (uint256);
    function transfer(address to, uint256 value) public returns (bool);
    event Transfer(address indexed from, address indexed to, uint256 value);
}

// File: contracts/token/ERC20.sol

/**
 * @title ERC20 interface
 * @dev see https://github.com/ethereum/EIPs/issues/20
 *
 * Based on OpenZeppelin
 */

contract ERC20 is ERC20Basic {
    function allowance(address owner, address spender) public constant returns (uint256);
    function transferFrom(address from, address to, uint256 value) public returns (bool);
    function approve(address spender, uint256 value) public returns (bool);
    event Approval(address indexed owner, address indexed spender, uint256 value);
}

// File: contracts/token/StandardToken.sol

/**
 * @title Standard ERC20 token
 *
 * @dev Implementation of the basic standard token.
 * @dev https://github.com/ethereum/EIPs/issues/20
 * @dev Based on code by FirstBlood: https://github.com/Firstbloodio/token/blob/master/smart_contract/FirstBloodToken.sol
 *
 * Based on OpenZeppelin
 */
contract StandardToken is ERC20 {

    using SafeMath for uint256;

    mapping(address => uint256) balances;

    mapping (address => mapping (address => uint256)) internal allowed;

    /**
  * @dev transfer token for a specified address
  * @param _to The address to transfer to.
  * @param _value The amount to be transferred.
  */
    function transfer(address _to, uint256 _value) public returns (bool) {
        require(_to != address(0));
        require(_value <= balances[msg.sender]);

        // SafeMath.sub will throw if there is not enough balance.
        balances[msg.sender] = balances[msg.sender].sub(_value);
        balances[_to] = balances[_to].add(_value);
        Transfer(msg.sender, _to, _value);
        return true;
    }

    /**
    * @dev Gets the balance of the specified address.
    * @param _owner The address to query the the balance of.
    * @return An uint256 representing the amount owned by the passed address.
    */
    function balanceOf(address _owner) public constant returns (uint256 balance) {
        return balances[_owner];
    }

    /**
     * @dev Transfer tokens from one address to another
     * @param _from address The address which you want to send tokens from
     * @param _to address The address which you want to transfer to
     * @param _value uint256 the amount of tokens to be transferred
     */
    function transferFrom(address _from, address _to, uint256 _value) public returns (bool) {
        require(_to != address(0));
        require(_value <= balances[_from]);
        require(_value <= allowed[_from][msg.sender]);

        balances[_from] = balances[_from].sub(_value);
        balances[_to] = balances[_to].add(_value);
        allowed[_from][msg.sender] = allowed[_from][msg.sender].sub(_value);
        Transfer(_from, _to, _value);
        return true;
    }

    /**
     * @dev Approve the passed address to spend the specified amount of tokens on behalf of msg.sender.
     *
     * Beware that changing an allowance with this method brings the risk that someone may use both the old
     * and the new allowance by unfortunate transaction ordering. One possible solution to mitigate this
     * race condition is to first reduce the spender's allowance to 0 and set the desired value afterwards:
     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
     * @param _spender The address which will spend the funds.
     * @param _value The amount of tokens to be spent.
     */
    function approve(address _spender, uint256 _value) public returns (bool) {
        allowed[msg.sender][_spender] = _value;
        Approval(msg.sender, _spender, _value);
        return true;
    }

    /**
     * @dev Function to check the amount of tokens that an owner allowed to a spender.
     * @param _owner address The address which owns the funds.
     * @param _spender address The address which will spend the funds.
     * @return A uint256 specifying the amount of tokens still available for the spender.
     */
    function allowance(address _owner, address _spender) public constant returns (uint256) {
        return allowed[_owner][_spender];
    }

    /**
     * approve should be called when allowed[_spender] == 0. To increment
     * allowed value is better to use this function to avoid 2 calls (and wait until
     * the first transaction is mined)
     * From MonolithDAO Token.sol
     */
    function increaseApproval (address _spender, uint _addedValue) public returns (bool) {
        allowed[msg.sender][_spender] = allowed[msg.sender][_spender].add(_addedValue);
        Approval(msg.sender, _spender, allowed[msg.sender][_spender]);
        return true;
    }

    function decreaseApproval (address _spender, uint _subtractedValue) public returns (bool) {
        uint oldValue = allowed[msg.sender][_spender];
        if (_subtractedValue > oldValue) {
            allowed[msg.sender][_spender] = 0;
        } else {
            allowed[msg.sender][_spender] = oldValue.sub(_subtractedValue);
        }
        Approval(msg.sender, _spender, allowed[msg.sender][_spender]);
        return true;
    }

}

// File: contracts/token/BurnableToken.sol

/**
 * @title Burnable Token
 *
 * @dev based on OpenZeppelin
 */
contract BurnableToken is StandardToken {

    event Burn(address indexed burner, uint256 value);

    /**
     * @dev Burns a specific amount of tokens.
     * @param _value The amount of token to be burned.
     */
    function burn(uint256 _value) public {
        require(_value > 0);
        require(_value <= balances[msg.sender]);

        address burner = msg.sender;
        balances[burner] = balances[burner].sub(_value);
        totalSupply = totalSupply.sub(_value);
        Burn(burner, _value);
    }
}

// File: contracts/ownership/Ownable.sol

/**
 * @title Ownable
 * @dev The Ownable contract has an owner address, and provides basic authorization control
 * functions, this simplifies the implementation of "user permissions".
 * Based on OpenZeppelin
 */
contract Ownable {
  address public owner;


  event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);


  /**
   * @dev The Ownable constructor sets the original `owner` of the contract to the sender
   * account.
   */
  function Ownable() {
    owner = msg.sender;
  }


  /**
   * @dev Throws if called by any account other than the owner.
   */
  modifier onlyOwner() {
    require(msg.sender == owner);
    _;
  }


  /**
   * @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) onlyOwner public {
    require(newOwner != address(0));
    OwnershipTransferred(owner, newOwner);
    owner = newOwner;
  }

}

// File: contracts/ownership/Claimable.sol

/**
 * @title Claimable
 * @dev Extension for the Ownable contract, where the ownership needs to be claimed.
 * This allows the new owner to accept the transfer.
 * Based on OpenZeppelin
 */
contract Claimable is Ownable {
    address public pendingOwner;

    /**
     * @dev Modifier throws if called by any account other than the pendingOwner.
     */
    modifier onlyPendingOwner() {
        require(msg.sender == pendingOwner);
        _;
    }

    /**
     * @dev Allows the current owner to set the pendingOwner address.
     * @param newOwner The address to transfer ownership to.
     */
    function transferOwnership(address newOwner) onlyOwner public {
        pendingOwner = newOwner;
    }

    /**
     * @dev Allows the pendingOwner address to finalize the transfer.
     */
    function claimOwnership() onlyPendingOwner public {
        OwnershipTransferred(owner, pendingOwner);
        owner = pendingOwner;
        pendingOwner = address(0);
    }
}

// File: contracts/token/ReleasableToken.sol

/**
 * Define interface for releasing the token transfer after a successful crowdsale.
 *
 */
contract ReleasableToken is ERC20, Claimable {

    /* The finalizer contract that allows unlift the transfer limits on this token */
    address public releaseAgent;

    /** A crowdsale contract can release us to the wild if ICO success. If false we are are in transfer lock up period.*/
    bool public released = false;

    /** Map of agents that are allowed to transfer tokens regardless of the lock down period. These are crowdsale contracts and possible the team multisig itself. */
    mapping (address => bool) public transferAgents;

    /**
     * Limit token transfer until the crowdsale is over.
     *
     */
    modifier canTransfer(address _sender) {
        if(!released) {
            assert(transferAgents[_sender]);
        }
        _;
    }

    /**
     * Set the contract that can call release and make the token transferable.
     *
     * Design choice. Allow reset the release agent to fix fat finger mistakes.
     */
    function setReleaseAgent(address addr) onlyOwner inReleaseState(false) public {
        require(addr != 0x0);
        // We don't do interface check here as we might want to a normal wallet address to act as a release agent
        releaseAgent = addr;
    }

    /**
     * Owner can allow a particular address (a crowdsale contract) to transfer tokens despite the lock up period.
     */
    function setTransferAgent(address addr, bool state) onlyOwner inReleaseState(false) public {
        require(addr != 0x0);
        transferAgents[addr] = state;
    }

    /**
     * One way function to release the tokens to the wild.
     *
     * Can be called only from the release agent that is the final ICO contract. It is only called if the crowdsale has been success (first milestone reached).
     */
    function releaseTokenTransfer() public onlyReleaseAgent {
        released = true;
    }

    /** The function can be called only before or after the tokens have been releasesd */
    modifier inReleaseState(bool releaseState) {
        require(releaseState == released);
        _;
    }

    /** The function can be called only by a whitelisted release agent. */
    modifier onlyReleaseAgent() {
        require(msg.sender == releaseAgent);
        _;
    }

    function transfer(address _to, uint _value) canTransfer(msg.sender) returns (bool success) {
        // Call StandardToken.transfer()
        return super.transfer(_to, _value);
    }

    function transferFrom(address _from, address _to, uint _value) canTransfer(_from) returns (bool success) {
        // Call StandardToken.transferForm()
        return super.transferFrom(_from, _to, _value);
    }

}

// File: contracts/token/CrowdsaleToken.sol

/**
 * @title Base crowdsale token interface
 */
contract CrowdsaleToken is BurnableToken, ReleasableToken {
    uint public decimals;
}

// File: contracts/token/UpgradeAgent.sol

/**
 * Upgrade agent interface inspired by Lunyr.
 *
 * Upgrade agent transfers tokens to a new contract.
 * Upgrade agent itself can be the token contract, or just a middle man contract doing the heavy lifting.
 *
 */
contract UpgradeAgent {

    uint public originalSupply;

    /** Interface marker */
    function isUpgradeAgent() public constant returns (bool) {
        return true;
    }

    function upgradeFrom(address _from, uint256 _value) public;
}

// File: contracts/token/UpgradeableToken.sol

/**
 * A token upgrade mechanism where users can opt-in amount of tokens to the next smart contract revision.
 *
 * First envisioned by Golem and Lunyr projects.
 *
 */
contract UpgradeableToken is StandardToken {

    /** Contract / person who can set the upgrade path. This can be the same as team multisig wallet, as what it is with its default value. */
    address public upgradeMaster;

    /** The next contract where the tokens will be migrated. */
    UpgradeAgent public upgradeAgent;

    /** How many tokens we have upgraded by now. */
    uint256 public totalUpgraded;

    /**
     * Upgrade states.
     *
     * - NotAllowed: The child contract has not reached a condition where the upgrade can bgun
     * - WaitingForAgent: Token allows upgrade, but we don't have a new agent yet
     * - ReadyToUpgrade: The agent is set, but not a single token has been upgraded yet
     * - Upgrading: Upgrade agent is set and the balance holders can upgrade their tokens
     *
     */
    enum UpgradeState {Unknown, NotAllowed, WaitingForAgent, ReadyToUpgrade, Upgrading}

    /**
     * Somebody has upgraded some of his tokens.
     */
    event Upgrade(address indexed _from, address indexed _to, uint256 _value);

    /**
     * New upgrade agent available.
     */
    event UpgradeAgentSet(address agent);

    /**
     * Do not allow construction without upgrade master set.
     */
    function UpgradeableToken(address _upgradeMaster) {
        upgradeMaster = _upgradeMaster;
    }

    /**
     * Allow the token holder to upgrade some of their tokens to a new contract.
     */
    function upgrade(uint256 value) public {
        require(value != 0);
        UpgradeState state = getUpgradeState();
        assert(state == UpgradeState.ReadyToUpgrade || state == UpgradeState.Upgrading);
        assert(value <= balanceOf(msg.sender));

        balances[msg.sender] = balances[msg.sender].sub(value);

        // Take tokens out from circulation
        totalSupply = totalSupply.sub(value);
        totalUpgraded = totalUpgraded.add(value);

        // Upgrade agent reissues the tokens
        upgradeAgent.upgradeFrom(msg.sender, value);
        Upgrade(msg.sender, upgradeAgent, value);
    }

    /**
     * Set an upgrade agent that handles
     */
    function setUpgradeAgent(address agent) external {
        require(agent != 0x0 && msg.sender == upgradeMaster);
        assert(canUpgrade());
        upgradeAgent = UpgradeAgent(agent);
        assert(upgradeAgent.isUpgradeAgent());
        assert(upgradeAgent.originalSupply() == totalSupply);
        UpgradeAgentSet(upgradeAgent);
    }

    /**
     * Get the state of the token upgrade.
     */
    function getUpgradeState() public constant returns(UpgradeState) {
        if(!canUpgrade()) return UpgradeState.NotAllowed;
        else if(address(upgradeAgent) == 0x00) return UpgradeState.WaitingForAgent;
        else if(totalUpgraded == 0) return UpgradeState.ReadyToUpgrade;
        else return UpgradeState.Upgrading;
    }

    /**
     * Change the upgrade master.
     *
     * This allows us to set a new owner for the upgrade mechanism.
     */
    function setUpgradeMaster(address master) public {
        require(master != 0x0 && msg.sender == upgradeMaster);
        upgradeMaster = master;
    }

    /**
     * Child contract can enable to provide the condition when the upgrade can begun.
     */
    function canUpgrade() public constant returns(bool) {
        return true;
    }

}

// File: contracts/token/AlgoryToken.sol

/**
 * @title Algory Token
 *
 * @dev based on OpenZeppelin
 *
 * Apache License, version 2.0 https://github.com/AlgoryProject/algory-ico/blob/master/LICENSE
 */
contract AlgoryToken is UpgradeableToken, CrowdsaleToken {

    string public name = 'Algory';
    string public symbol = 'ALG';
    uint public decimals = 18;

    uint256 public INITIAL_SUPPLY = 75000000 * (10 ** uint256(decimals));

    event UpdatedTokenInformation(string newName, string newSymbol);

    function AlgoryToken() UpgradeableToken(msg.sender) {
        owner = msg.sender;
        totalSupply = INITIAL_SUPPLY;
        balances[owner] = totalSupply;
    }

    function canUpgrade() public constant returns(bool) {
        return released && super.canUpgrade();
    }

    function setTokenInformation(string _name, string _symbol) onlyOwner {
        name = _name;
        symbol = _symbol;
        UpdatedTokenInformation(name, symbol);
    }

}