pragma solidity ^0.4.0;

/*
    Copyright 2017, Jordi Baylina
    Contributors: Adrià Massanet <adria@codecontext.io>, RJ Ewing, Griff
    Green, Arthur Lunn

    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/>.
*/


/// @dev `ILiquidPledgingPlugin` is the basic interface for any
///  liquid pledging plugin
contract ILiquidPledgingPlugin {

    /// @notice Plugins are used (much like web hooks) to initiate an action
    ///  upon any donation, delegation, or transfer; this is an optional feature
    ///  and allows for extreme customization of the contract. This function
    ///  implements any action that should be initiated before a transfer.
    /// @param pledgeManager The admin or current manager of the pledge
    /// @param pledgeFrom This is the Id from which value will be transfered.
    /// @param pledgeTo This is the Id that value will be transfered to.    
    /// @param context The situation that is triggering the plugin:
    ///  0 -> Plugin for the owner transferring pledge to another party
    ///  1 -> Plugin for the first delegate transferring pledge to another party
    ///  2 -> Plugin for the second delegate transferring pledge to another party
    ///  ...
    ///  255 -> Plugin for the intendedProject transferring pledge to another party
    ///
    ///  256 -> Plugin for the owner receiving pledge to another party
    ///  257 -> Plugin for the first delegate receiving pledge to another party
    ///  258 -> Plugin for the second delegate receiving pledge to another party
    ///  ...
    ///  511 -> Plugin for the intendedProject receiving pledge to another party
    /// @param amount The amount of value that will be transfered.
    function beforeTransfer(
        uint64 pledgeManager,
        uint64 pledgeFrom,
        uint64 pledgeTo,
        uint64 context,
        address token,
        uint amount ) public returns (uint maxAllowed);

    /// @notice Plugins are used (much like web hooks) to initiate an action
    ///  upon any donation, delegation, or transfer; this is an optional feature
    ///  and allows for extreme customization of the contract. This function
    ///  implements any action that should be initiated after a transfer.
    /// @param pledgeManager The admin or current manager of the pledge
    /// @param pledgeFrom This is the Id from which value will be transfered.
    /// @param pledgeTo This is the Id that value will be transfered to.    
    /// @param context The situation that is triggering the plugin:
    ///  0 -> Plugin for the owner transferring pledge to another party
    ///  1 -> Plugin for the first delegate transferring pledge to another party
    ///  2 -> Plugin for the second delegate transferring pledge to another party
    ///  ...
    ///  255 -> Plugin for the intendedProject transferring pledge to another party
    ///
    ///  256 -> Plugin for the owner receiving pledge to another party
    ///  257 -> Plugin for the first delegate receiving pledge to another party
    ///  258 -> Plugin for the second delegate receiving pledge to another party
    ///  ...
    ///  511 -> Plugin for the intendedProject receiving pledge to another party
    ///  @param amount The amount of value that will be transfered.
    function afterTransfer(
        uint64 pledgeManager,
        uint64 pledgeFrom,
        uint64 pledgeTo,
        uint64 context,
        address token,
        uint amount
    ) public;
}