// SPDX-License-Identifier: MIT
pragma solidity 0.8.19;

import {ReentrancyGuard} from "@openzeppelin/contracts/security/ReentrancyGuard.sol";
import {IERC20} from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import {HasSignature} from "../core/HasSignature.sol";

/**
 * Contract for the activity of NFT claim stage 2.
 */
interface IClaimAbleNFT {
  function safeMint(address to, uint256 tokenID) external;
}

contract NFTClaimStage2 is HasSignature, ReentrancyGuard {
  struct MintConfig {
    uint256 parse1MaxSupply; // max supply for phase1
    uint256 maxSupply; // max supply for phase2
    address currency; // token address which user must pay to mint
    uint256 mintPrice; // in wei
    address feeToAddress; // wallet address to receive mint fee
  }
  // parse: 0: not open or end, 1: phase1, 2: phase2
  uint256 public mintParse = 0;

  uint256 public immutable _CACHED_CHAIN_ID;
  address public immutable _CACHED_THIS;
  address public immutable nftAddress;

  address public verifier;
  MintConfig public mintConfig;
  uint256 public parse1Count;
  uint256 public totalCount;

  event NFTClaimed(address indexed nftAddress, address indexed to, uint256[] ids);

  event ParseUpdated(uint256 _parse);
  event MintConfigUpdated(MintConfig config);
  event VerifierUpdated(address indexed verifier);

  constructor(address _nftAddress, address _verifier, MintConfig memory _mintConfig) {
    _CACHED_CHAIN_ID = block.chainid;
    _CACHED_THIS = address(this);
    nftAddress = _nftAddress;
    verifier = _verifier;
    mintConfig = _mintConfig;
  }

  modifier whenNotPaused() {
    require(mintParse > 0, "NFTClaimer: not begin or ended");
    _;
  }

  function updateMintParse(uint256 _mintParse) external onlyOwner {
    mintParse = _mintParse;
    emit ParseUpdated(_mintParse);
  }

  function updateMintConfig(MintConfig calldata config) external onlyOwner {
    mintConfig = config;
    emit MintConfigUpdated(config);
  }

  /**
   * @dev update verifier address
   */
  function updateVerifier(address _verifier) external onlyOwner {
    require(_verifier != address(0), "NFTClaimer: address can not be zero");
    verifier = _verifier;
    emit VerifierUpdated(_verifier);
  }

  /**
   * @dev claim NFT
   * Get whitelist signature from a third-party service, then call this method to claim NFT
   * @param saltNonce nonce
   * @param signature signature
   */
  function claim(
    uint256[] memory ids,
    uint256 tokenAmount,
    uint256 saltNonce,
    bytes calldata signature
  ) external nonReentrant whenNotPaused {
    // get current parse;
    uint256 count = ids.length;
    require(count > 0, "NFTClaimer: ids length must be greater than 0");
    if (mintParse == 1) {
      require(count <= mintConfig.parse1MaxSupply - parse1Count, "NFTClaimer: exceed parse 1 max supply");
    } else {
      require(count <= mintConfig.maxSupply - totalCount, "NFTClaimer: exceed max supply");
    }
    require(tokenAmount >= mintConfig.mintPrice * count, "NFTClaimer: insufficient token amount");
    address to = _msgSender();
    bytes32 criteriaMessageHash = getMessageHash(
      to,
      nftAddress,
      ids,
      tokenAmount,
      _CACHED_THIS,
      _CACHED_CHAIN_ID,
      saltNonce
    );
    checkSigner(verifier, criteriaMessageHash, signature);
    IERC20(mintConfig.currency).transferFrom(to, mintConfig.feeToAddress, tokenAmount);
    for (uint256 i = 0; i < count; ++i) {
      IClaimAbleNFT(nftAddress).safeMint(to, ids[i]);
    }
    // require(count > 2, "run to here");
    totalCount += count;
    if (mintParse == 1) {
      parse1Count += count;
    }
    _useSignature(signature);
    emit NFTClaimed(nftAddress, to, ids);
  }

  function getMessageHash(
    address _to,
    address _address,
    uint256[] memory _ids,
    uint256 _tokenAmount,
    address _contract,
    uint256 _chainId,
    uint256 _saltNonce
  ) public pure returns (bytes32) {
    bytes memory encoded = abi.encodePacked(_to, _address, _tokenAmount, _contract, _chainId, _saltNonce);
    for (uint256 i = 0; i < _ids.length; ++i) {
      encoded = bytes.concat(encoded, abi.encodePacked(_ids[i]));
    }
    return keccak256(encoded);
  }
}