// SPDX-License-Identifier: GPL-3.0

pragma solidity =0.8.6;

import "@openzeppelin/contracts-upgradeable/utils/cryptography/MerkleProofUpgradeable.sol";
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "@openzeppelin/contracts-upgradeable/access/OwnableUpgradeable.sol";
import "@openzeppelin/contracts-upgradeable/proxy/utils/Initializable.sol";
import "../Interfaces/IMerkleTreeDistributor.sol";
import "../Interfaces/IDistro.sol";

// Based on: https://github.com/Uniswap/merkle-distributor/blob/master/contracts/MerkleDistributor.sol
/*
 * Changelog:
 *      * Added SPDX-License-Identifier
 *      * Update to solidity ^0.8.0
 *      * Update openzeppelin imports
 *      * Make it upgradable
 *      * Add claimTo function that allows the owner to claim on behalf of someone
 */

contract MerkleDrop is IMerkleTreeDistributor, Initializable, OwnableUpgradeable {
    address public token;
    bytes32 public override merkleRoot;

    // This is a packed array of booleans.
    mapping(uint256 => uint256) private claimedBitMap;

    function initialize(address _token, bytes32 _merkleRoot) public initializer {
        __Ownable_init();
        token = _token;
        merkleRoot = _merkleRoot;
    }

    function isClaimed(uint256 index) public view override returns (bool) {
        uint256 claimedWordIndex = index / 256;
        uint256 claimedBitIndex = index % 256;
        uint256 claimedWord = claimedBitMap[claimedWordIndex];
        uint256 mask = (1 << claimedBitIndex);
        return claimedWord & mask == mask;
    }

    function _setClaimed(uint256 index) private {
        uint256 claimedWordIndex = index / 256;
        uint256 claimedBitIndex = index % 256;
        claimedBitMap[claimedWordIndex] =
            claimedBitMap[claimedWordIndex] |
            (1 << claimedBitIndex);
    }

    function claim(
        uint256 index,
        address account,
        uint256 amount,
        bytes32[] calldata merkleProof
    ) external override {
        require(
            !isClaimed(index),
            "MerkleDrop::claim Drop already claimed."
        );

        // Verify the merkle proof.
        bytes32 node = keccak256(abi.encodePacked(index, account, amount));
        require(
            MerkleProofUpgradeable.verify(merkleProof, merkleRoot, node),
            "MerkleDrop::claim Invalid proof."
        );

        // Mark it claimed and send and grant the vested tokens
        _setClaimed(index);
        require(IERC20(token).transfer(account, amount), 'MerkleDrop: Transfer failed.');

        emit Claimed(index, account, account, amount);
    }

    /**
        This function allows to the owner to claim tokens in behalf of another to a different address
        It is intended for those cases in which the owner knows that the recipient is no longer in possession of the account.
     */
    function claimTo(
        uint256 index,
        address account,
        address recipient,
        uint256 amount,
        bytes32[] calldata merkleProof
    ) external override onlyOwner {
        require(
            !isClaimed(index),
            "MerkleDrop::claim Drop already claimed."
        );

        // Verify the merkle proof.
        bytes32 node = keccak256(abi.encodePacked(index, account, amount));
        require(
            MerkleProofUpgradeable.verify(merkleProof, merkleRoot, node),
            "MerkleDrop::claim Invalid proof."
        );

        // Mark it claimed and send the tokens
        _setClaimed(index);
        require(IERC20(token).transfer(recipient, amount), 'MerkleDrop: Transfer failed.');

        emit Claimed(index, account, recipient, amount);
    }
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/**
 * @dev These functions deal with verification of Merkle Trees proofs.
 *
 * The proofs can be generated using the JavaScript library
 * https://github.com/miguelmota/merkletreejs[merkletreejs].
 * Note: the hashing algorithm should be keccak256 and pair sorting should be enabled.
 *
 * See `test/utils/cryptography/MerkleProof.test.js` for some examples.
 */
library MerkleProofUpgradeable {
    /**
     * @dev Returns true if a `leaf` can be proved to be a part of a Merkle tree
     * defined by `root`. For this, a `proof` must be provided, containing
     * sibling hashes on the branch from the leaf to the root of the tree. Each
     * pair of leaves and each pair of pre-images are assumed to be sorted.
     */
    function verify(bytes32[] memory proof, bytes32 root, bytes32 leaf) internal pure returns (bool) {
        bytes32 computedHash = leaf;

        for (uint256 i = 0; i < proof.length; i++) {
            bytes32 proofElement = proof[i];

            if (computedHash <= proofElement) {
                // Hash(current computed hash + current element of the proof)
                computedHash = keccak256(abi.encodePacked(computedHash, proofElement));
            } else {
                // Hash(current element of the proof + current computed hash)
                computedHash = keccak256(abi.encodePacked(proofElement, computedHash));
            }
        }

        // Check if the computed hash (root) is equal to the provided root
        return computedHash == root;
    }
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20 {
    /**
     * @dev Returns the amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256);

    /**
     * @dev Returns the amount of tokens owned by `account`.
     */
    function balanceOf(address account) external view returns (uint256);

    /**
     * @dev Moves `amount` tokens from the caller's account to `recipient`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address recipient, uint256 amount) external returns (bool);

    /**
     * @dev Returns the remaining number of tokens that `spender` will be
     * allowed to spend on behalf of `owner` through {transferFrom}. This is
     * zero by default.
     *
     * This value changes when {approve} or {transferFrom} are called.
     */
    function allowance(address owner, address spender) external view returns (uint256);

    /**
     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * IMPORTANT: 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
     *
     * Emits an {Approval} event.
     */
    function approve(address spender, uint256 amount) external returns (bool);

    /**
     * @dev Moves `amount` tokens from `sender` to `recipient` using the
     * allowance mechanism. `amount` is then deducted from the caller's
     * allowance.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(
        address sender,
        address recipient,
        uint256 amount
    ) external returns (bool);

    /**
     * @dev Emitted when `value` tokens are moved from one account (`from`) to
     * another (`to`).
     *
     * Note that `value` may be zero.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);

    /**
     * @dev Emitted when the allowance of a `spender` for an `owner` is set by
     * a call to {approve}. `value` is the new allowance.
     */
    event Approval(address indexed owner, address indexed spender, uint256 value);
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "../utils/ContextUpgradeable.sol";
import "../proxy/utils/Initializable.sol";
/**
 * @dev Contract module which provides a basic access control mechanism, where
 * there is an account (an owner) that can be granted exclusive access to
 * specific functions.
 *
 * By default, the owner account will be the one that deploys the contract. This
 * can later be changed with {transferOwnership}.
 *
 * This module is used through inheritance. It will make available the modifier
 * `onlyOwner`, which can be applied to your functions to restrict their use to
 * the owner.
 */
abstract contract OwnableUpgradeable is Initializable, ContextUpgradeable {
    address private _owner;

    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);

    /**
     * @dev Initializes the contract setting the deployer as the initial owner.
     */
    function __Ownable_init() internal initializer {
        __Context_init_unchained();
        __Ownable_init_unchained();
    }

    function __Ownable_init_unchained() internal initializer {
        address msgSender = _msgSender();
        _owner = msgSender;
        emit OwnershipTransferred(address(0), msgSender);
    }

    /**
     * @dev Returns the address of the current owner.
     */
    function owner() public view virtual returns (address) {
        return _owner;
    }

    /**
     * @dev Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        require(owner() == _msgSender(), "Ownable: caller is not the owner");
        _;
    }

    /**
     * @dev Leaves the contract without owner. It will not be possible to call
     * `onlyOwner` functions anymore. Can only be called by the current owner.
     *
     * NOTE: Renouncing ownership will leave the contract without an owner,
     * thereby removing any functionality that is only available to the owner.
     */
    function renounceOwnership() public virtual onlyOwner {
        emit OwnershipTransferred(_owner, address(0));
        _owner = address(0);
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Can only be called by the current owner.
     */
    function transferOwnership(address newOwner) public virtual onlyOwner {
        require(newOwner != address(0), "Ownable: new owner is the zero address");
        emit OwnershipTransferred(_owner, newOwner);
        _owner = newOwner;
    }
    uint256[49] private __gap;
}

// SPDX-License-Identifier: MIT

// solhint-disable-next-line compiler-version
pragma solidity ^0.8.0;

/**
 * @dev This is a base contract to aid in writing upgradeable contracts, or any kind of contract that will be deployed
 * behind a proxy. Since a proxied contract can't have a constructor, it's common to move constructor logic to an
 * external initializer function, usually called `initialize`. It then becomes necessary to protect this initializer
 * function so it can only be called once. The {initializer} modifier provided by this contract will have this effect.
 *
 * TIP: To avoid leaving the proxy in an uninitialized state, the initializer function should be called as early as
 * possible by providing the encoded function call as the `_data` argument to {ERC1967Proxy-constructor}.
 *
 * CAUTION: When used with inheritance, manual care must be taken to not invoke a parent initializer twice, or to ensure
 * that all initializers are idempotent. This is not verified automatically as constructors are by Solidity.
 */
abstract contract Initializable {

    /**
     * @dev Indicates that the contract has been initialized.
     */
    bool private _initialized;

    /**
     * @dev Indicates that the contract is in the process of being initialized.
     */
    bool private _initializing;

    /**
     * @dev Modifier to protect an initializer function from being invoked twice.
     */
    modifier initializer() {
        require(_initializing || !_initialized, "Initializable: contract is already initialized");

        bool isTopLevelCall = !_initializing;
        if (isTopLevelCall) {
            _initializing = true;
            _initialized = true;
        }

        _;

        if (isTopLevelCall) {
            _initializing = false;
        }
    }
}

// SPDX-License-Identifier: GPL-3.0

pragma solidity =0.8.6;

// Allows anyone to claim a token if they exist in a merkle root.
interface IMerkleTreeDistributor {
    // Returns the merkle root of the merkle tree containing account balances available to claim.
    function merkleRoot() external view returns (bytes32);

    // Returns true if the index has been marked claimed.
    function isClaimed(uint256 index) external view returns (bool);

    // Claim the given amount of the token to the given address. Reverts if the inputs are invalid.
    function claim(
        uint256 index,
        address account,
        uint256 amount,
        bytes32[] calldata merkleProof
    ) external;

    // Claim the given amount of the token to the given address to a specific recipient. Reverts if the inputs are invalid.
    function claimTo(
        uint256 index,
        address account,
        address recipient,
        uint256 amount,
        bytes32[] calldata merkleProof
    ) external;

    // This event is triggered whenever a call to #claim succeeds.
    event Claimed(
        uint256 index,
        address account,
        address recipient,
        uint256 amount
    );
}

// SPDX-License-Identifier: GPL-3.0

pragma solidity =0.8.6;

interface IDistro {
    /**
     * @dev Emitted when someone makes a claim of tokens
     */
    event Claim(address indexed grantee, uint256 amount);
    /**
     * @dev Emitted when the DISTRIBUTOR allocate an amount to a grantee
     */
    event Allocate(
        address indexed distributor,
        address indexed grantee,
        uint256 amount
    );
    /**
     * @dev Emitted when the DEFAULT_ADMIN assign an amount to a DISTRIBUTOR
     */
    event Assign(
        address indexed admin,
        address indexed distributor,
        uint256 amount
    );
    /**
     * @dev Emitted when someone change their reception address
     */
    event ChangeAddress(address indexed oldAddress, address indexed newAddress);

    /**
     * @dev Emitted when a new startTime is set
     */
    event StartTimeChanged(uint256 newStartTime);

    /**
     * Function that allows the DEFAULT_ADMIN_ROLE to assign set a new startTime if it hasn't started yet
     * @param newStartTime new startTime
     *
     * Emits a {StartTimeChanged} event.
     *
     */
    function setStartTime(uint256 newStartTime) external;

    /**
     * Function that allows the DEFAULT_ADMIN_ROLE to assign tokens to an address who later can distribute them.
     * @dev It is required that the DISTRIBUTOR_ROLE is already held by the address to which an amount will be assigned
     * @param distributor the address, generally a smart contract, that will determine who gets how many tokens
     * @param amount Total amount of tokens to assign to that address for distributing
     */
    function assign(address distributor, uint256 amount) external;

    /**
     * Function to claim tokens for a specific address. It uses the current timestamp
     */
    function claim() external;

    /**
     * Function that allows to the distributor address to allocate some amount of tokens to a specific recipient
     * @dev Needs to be initialized: Nobody has the DEFAULT_ADMIN_ROLE and all available tokens have been assigned
     * @param recipient of token allocation
     * @param amount allocated amount
     */
    function allocate(address recipient, uint256 amount) external;

    /**
     * Function that allows a recipient to change its address
     * @dev The change can only be made to an address that has not previously received an allocation &
     * the distributor cannot change its address
     */
    function changeAddress(address newAddress) external;

    /**
     * Function to get the current timestamp from the block
     */
    function getTimestamp() external view returns (uint256);

    /**
     * Function to get the total unlocked tokes at some moment
     */
    function globallyClaimableAt(uint256 timestamp)
        external
        view
        returns (uint256);

    /**
     * Function to get the unlocked tokes at some moment for a specific address
     */
    function claimableAt(address recipient, uint256 timestamp)
        external
        view
        returns (uint256);

    /**
     * Function to get the unlocked tokens for a specific address. It uses the current timestamp
     */
    function claimableNow(address recipient) external view returns (uint256);

    function cancelAllocation(address prevRecipient, address newRecipient)
        external;
}

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;
import "../proxy/utils/Initializable.sol";

/*
 * @dev Provides information about the current execution context, including the
 * sender of the transaction and its data. While these are generally available
 * via msg.sender and msg.data, they should not be accessed in such a direct
 * manner, since when dealing with meta-transactions the account sending and
 * paying for execution may not be the actual sender (as far as an application
 * is concerned).
 *
 * This contract is only required for intermediate, library-like contracts.
 */
abstract contract ContextUpgradeable is Initializable {
    function __Context_init() internal initializer {
        __Context_init_unchained();
    }

    function __Context_init_unchained() internal initializer {
    }
    function _msgSender() internal view virtual returns (address) {
        return msg.sender;
    }

    function _msgData() internal view virtual returns (bytes calldata) {
        this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
        return msg.data;
    }
    uint256[50] private __gap;
}


{"success": true, "error": null, "results": {}}