// File: /contracts/factory/extensions/WhitelistMerkleTreeExtension.sol



// SPDX-License-Identifier: MIT
pragma solidity ^0.8.9;

import "@openzeppelin/contracts/access/Ownable.sol";
import "@openzeppelin/contracts/security/Pausable.sol";
import "@openzeppelin/contracts/utils/cryptography/MerkleProof.sol";

import "./NFTExtension.sol";
import "./SaleControl.sol";

contract WhitelistMerkleTreeExtension is NFTExtension, Ownable, SaleControl {

    uint256 public price;
    uint256 public maxPerAddress;

    bytes32 public whitelistRoot;

    mapping (address => uint256) claimedByAddress;

    constructor(address _nft, bytes32 _whitelistRoot, uint256 _price, uint256 _maxPerAddress) NFTExtension(_nft) SaleControl() {
        stopSale();

        price = _price;
        maxPerAddress = _maxPerAddress;
        whitelistRoot = _whitelistRoot;
    }

    function updateMaxPerAddress(uint256 _maxPerAddress) public onlyOwner {
        maxPerAddress = _maxPerAddress;
    }

    function updateWhitelistRoot(bytes32 _whitelistRoot) public onlyOwner {
        whitelistRoot = _whitelistRoot;
    }

    function mint(uint256 nTokens, bytes32[] memory proof) external whenSaleStarted payable {
        super.beforeMint();

        require(isWhitelisted(whitelistRoot, msg.sender, proof), "Not whitelisted");

        require(claimedByAddress[msg.sender] + nTokens <= maxPerAddress, "Cannot claim more per address");

        require(msg.value >= nTokens * price, "Not enough ETH to mint");

        nft.mintExternal{ value: msg.value }(nTokens, msg.sender, bytes32(0x0));

        claimedByAddress[msg.sender] += nTokens;
    }

    function isWhitelisted(bytes32 root, address receiver, bytes32[] memory proof) public pure returns (bool) {
        bytes32 leaf = keccak256(abi.encodePacked(receiver));

        return MerkleProof.verify(proof, root, leaf);
    }

}

// File: /contracts/factory/extensions/SaleControl.sol



// SPDX-License-Identifier: MIT
pragma solidity ^0.8.9;

import "@openzeppelin/contracts/access/Ownable.sol";

abstract contract SaleControl is Ownable {

    uint256 public constant __SALE_NEVER_STARTS = 2**256 - 1;

    uint256 public startTimestamp = __SALE_NEVER_STARTS;

    modifier whenSaleStarted {
        require(saleStarted(), "Sale not started yet");
        _;
    }

    function updateStartTimestamp(uint256 _startTimestamp) public onlyOwner {
        startTimestamp = _startTimestamp;
    }

    function startSale() public onlyOwner {
        startTimestamp = block.timestamp;
    }

    function stopSale() public onlyOwner {
        startTimestamp = __SALE_NEVER_STARTS;
    }

    function saleStarted() public view returns (bool) {
        return block.timestamp > startTimestamp;
    }
}
// File: /contracts/factory/extensions/NFTExtension.sol



// SPDX-License-Identifier: MIT
pragma solidity ^0.8.9;

import "@openzeppelin/contracts/utils/introspection/ERC165.sol";

import "./INFTExtension.sol";
import "../IMetaverseNFT.sol";

contract NFTExtension is INFTExtension, ERC165 {
    IMetaverseNFT public immutable nft;

    constructor(address _nft) {
        nft = IMetaverseNFT(_nft);
    }

    function beforeMint() internal view {
        require(nft.isExtensionAllowed(address(this)), "NFTExtension: this contract is not allowed to be used as an extension");
    }

    function supportsInterface(bytes4 interfaceId) public override(IERC165, ERC165) view returns (bool) {
        return interfaceId == type(INFTExtension).interfaceId || super.supportsInterface(interfaceId);
    }

}

// File: /contracts/factory/extensions/INFTExtension.sol



// SPDX-License-Identifier: MIT
pragma solidity ^0.8.9;

import "@openzeppelin/contracts/utils/introspection/IERC165.sol";

interface INFTExtension is IERC165 {
}

interface INFTURIExtension is INFTExtension {
    function tokenURI(uint256 tokenId) external view returns (string memory);
}

// File: /contracts/factory/IMetaverseNFT.sol



// SPDX-License-Identifier: MIT
pragma solidity ^0.8.9;

interface IMetaverseNFT {
    function isExtensionAllowed(address extension) external view returns (bool);
    function tokenData(uint256 tokenId) external view returns (bytes32);

    function mintExternal(uint256 nTokens, address to, bytes32 data) external payable;
    function addExtension(address extension) external;
    function revokeExtension(address extension) external;
}

// File: @openzeppelin/contracts/utils/introspection/IERC165.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/**
 * @dev Interface of the ERC165 standard, as defined in the
 * https://eips.ethereum.org/EIPS/eip-165[EIP].
 *
 * Implementers can declare support of contract interfaces, which can then be
 * queried by others ({ERC165Checker}).
 *
 * For an implementation, see {ERC165}.
 */
interface IERC165 {
    /**
     * @dev Returns true if this contract implements the interface defined by
     * `interfaceId`. See the corresponding
     * https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[EIP section]
     * to learn more about how these ids are created.
     *
     * This function call must use less than 30 000 gas.
     */
    function supportsInterface(bytes4 interfaceId) external view returns (bool);
}

// File: @openzeppelin/contracts/utils/introspection/ERC165.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "./IERC165.sol";

/**
 * @dev Implementation of the {IERC165} interface.
 *
 * Contracts that want to implement ERC165 should inherit from this contract and override {supportsInterface} to check
 * for the additional interface id that will be supported. For example:
 *
 * ```solidity
 * function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
 *     return interfaceId == type(MyInterface).interfaceId || super.supportsInterface(interfaceId);
 * }
 * ```
 *
 * Alternatively, {ERC165Storage} provides an easier to use but more expensive implementation.
 */
abstract contract ERC165 is IERC165 {
    /**
     * @dev See {IERC165-supportsInterface}.
     */
    function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
        return interfaceId == type(IERC165).interfaceId;
    }
}

// File: @openzeppelin/contracts/utils/cryptography/MerkleProof.sol



// 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 MerkleProof {
    /**
     * @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;
    }
}

// File: @openzeppelin/contracts/utils/Context.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/**
 * @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 Context {
    function _msgSender() internal view virtual returns (address) {
        return msg.sender;
    }

    function _msgData() internal view virtual returns (bytes calldata) {
        return msg.data;
    }
}

// File: @openzeppelin/contracts/security/Pausable.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "../utils/Context.sol";

/**
 * @dev Contract module which allows children to implement an emergency stop
 * mechanism that can be triggered by an authorized account.
 *
 * This module is used through inheritance. It will make available the
 * modifiers `whenNotPaused` and `whenPaused`, which can be applied to
 * the functions of your contract. Note that they will not be pausable by
 * simply including this module, only once the modifiers are put in place.
 */
abstract contract Pausable is Context {
    /**
     * @dev Emitted when the pause is triggered by `account`.
     */
    event Paused(address account);

    /**
     * @dev Emitted when the pause is lifted by `account`.
     */
    event Unpaused(address account);

    bool private _paused;

    /**
     * @dev Initializes the contract in unpaused state.
     */
    constructor() {
        _paused = false;
    }

    /**
     * @dev Returns true if the contract is paused, and false otherwise.
     */
    function paused() public view virtual returns (bool) {
        return _paused;
    }

    /**
     * @dev Modifier to make a function callable only when the contract is not paused.
     *
     * Requirements:
     *
     * - The contract must not be paused.
     */
    modifier whenNotPaused() {
        require(!paused(), "Pausable: paused");
        _;
    }

    /**
     * @dev Modifier to make a function callable only when the contract is paused.
     *
     * Requirements:
     *
     * - The contract must be paused.
     */
    modifier whenPaused() {
        require(paused(), "Pausable: not paused");
        _;
    }

    /**
     * @dev Triggers stopped state.
     *
     * Requirements:
     *
     * - The contract must not be paused.
     */
    function _pause() internal virtual whenNotPaused {
        _paused = true;
        emit Paused(_msgSender());
    }

    /**
     * @dev Returns to normal state.
     *
     * Requirements:
     *
     * - The contract must be paused.
     */
    function _unpause() internal virtual whenPaused {
        _paused = false;
        emit Unpaused(_msgSender());
    }
}

// File: @openzeppelin/contracts/access/Ownable.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "../utils/Context.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 Ownable is Context {
    address private _owner;

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

    /**
     * @dev Initializes the contract setting the deployer as the initial owner.
     */
    constructor() {
        _setOwner(_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 {
        _setOwner(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");
        _setOwner(newOwner);
    }

    function _setOwner(address newOwner) private {
        address oldOwner = _owner;
        _owner = newOwner;
        emit OwnershipTransferred(oldOwner, newOwner);
    }
}