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

import {ITypeAndVersion} from "../../shared/interfaces/ITypeAndVersion.sol";
import {IFunctionsCoordinator} from "./interfaces/IFunctionsCoordinator.sol";

import {FunctionsBilling} from "./FunctionsBilling.sol";

import {FunctionsResponse} from "./libraries/FunctionsResponse.sol";
import {OCR2Base} from "./ocr/OCR2Base.sol";

/// @title Functions Coordinator contract
/// @notice Contract that nodes of a Decentralized Oracle Network (DON) interact with
contract FunctionsCoordinator is OCR2Base, IFunctionsCoordinator, FunctionsBilling {
  using FunctionsResponse for FunctionsResponse.RequestMeta;
  using FunctionsResponse for FunctionsResponse.Commitment;
  using FunctionsResponse for FunctionsResponse.FulfillResult;

  /// @inheritdoc ITypeAndVersion
  string public constant override typeAndVersion = "Functions Coordinator v1.0.0";

  event OracleRequest(
    bytes32 indexed requestId,
    address indexed requestingContract,
    address requestInitiator,
    uint64 subscriptionId,
    address subscriptionOwner,
    bytes data,
    uint16 dataVersion,
    bytes32 flags,
    uint64 callbackGasLimit,
    FunctionsResponse.Commitment commitment
  );
  event OracleResponse(bytes32 indexed requestId, address transmitter);

  error InconsistentReportData();
  error EmptyPublicKey();
  error UnauthorizedPublicKeyChange();

  bytes private s_donPublicKey;
  bytes private s_thresholdPublicKey;

  constructor(
    address router,
    Config memory config,
    address linkToNativeFeed
  ) OCR2Base(true) FunctionsBilling(router, config, linkToNativeFeed) {}

  /// @inheritdoc IFunctionsCoordinator
  function getThresholdPublicKey() external view override returns (bytes memory) {
    if (s_thresholdPublicKey.length == 0) {
      revert EmptyPublicKey();
    }
    return s_thresholdPublicKey;
  }

  /// @inheritdoc IFunctionsCoordinator
  function setThresholdPublicKey(
    bytes calldata thresholdPublicKey
  ) external override onlyOwner {
    if (thresholdPublicKey.length == 0) {
      revert EmptyPublicKey();
    }
    s_thresholdPublicKey = thresholdPublicKey;
  }

  /// @inheritdoc IFunctionsCoordinator
  function getDONPublicKey() external view override returns (bytes memory) {
    if (s_donPublicKey.length == 0) {
      revert EmptyPublicKey();
    }
    return s_donPublicKey;
  }

  /// @inheritdoc IFunctionsCoordinator
  function setDONPublicKey(
    bytes calldata donPublicKey
  ) external override onlyOwner {
    if (donPublicKey.length == 0) {
      revert EmptyPublicKey();
    }
    s_donPublicKey = donPublicKey;
  }

  /// @dev check if node is in current transmitter list
  function _isTransmitter(
    address node
  ) internal view returns (bool) {
    address[] memory nodes = s_transmitters;
    // Bounded by "maxNumOracles" on OCR2Abstract.sol
    for (uint256 i = 0; i < nodes.length; ++i) {
      if (nodes[i] == node) {
        return true;
      }
    }
    return false;
  }

  /// @inheritdoc IFunctionsCoordinator
  function startRequest(
    FunctionsResponse.RequestMeta calldata request
  ) external override onlyRouter returns (FunctionsResponse.Commitment memory commitment) {
    commitment = _startBilling(request);

    emit OracleRequest(
      commitment.requestId,
      request.requestingContract,
      tx.origin,
      request.subscriptionId,
      request.subscriptionOwner,
      request.data,
      request.dataVersion,
      request.flags,
      request.callbackGasLimit,
      commitment
    );

    return commitment;
  }

  /// @dev DON fees are pooled together. If the OCR configuration is going to change, these need to be distributed.
  function _beforeSetConfig(uint8, /* _f */ bytes memory /* _onchainConfig */ ) internal override {
    if (_getTransmitters().length > 0) {
      _disperseFeePool();
    }
  }

  /// @dev Used by FunctionsBilling.sol
  function _getTransmitters() internal view override returns (address[] memory) {
    return s_transmitters;
  }

  /// @dev Report hook called within OCR2Base.sol
  function _report(
    uint256, /*initialGas*/
    address, /*transmitter*/
    uint8, /*signerCount*/
    address[MAX_NUM_ORACLES] memory, /*signers*/
    bytes calldata report
  ) internal override {
    bytes32[] memory requestIds;
    bytes[] memory results;
    bytes[] memory errors;
    bytes[] memory onchainMetadata;
    bytes[] memory offchainMetadata;
    (requestIds, results, errors, onchainMetadata, offchainMetadata) =
      abi.decode(report, (bytes32[], bytes[], bytes[], bytes[], bytes[]));

    if (
      requestIds.length == 0 || requestIds.length != results.length || requestIds.length != errors.length
        || requestIds.length != onchainMetadata.length || requestIds.length != offchainMetadata.length
    ) {
      revert ReportInvalid();
    }

    // Bounded by "MaxRequestBatchSize" on the Job's ReportingPluginConfig
    for (uint256 i = 0; i < requestIds.length; ++i) {
      FunctionsResponse.FulfillResult result = FunctionsResponse.FulfillResult(
        _fulfillAndBill(requestIds[i], results[i], errors[i], onchainMetadata[i], offchainMetadata[i])
      );

      // Emit on successfully processing the fulfillment
      // In these two fulfillment results the user has been charged
      // Otherwise, the DON will re-try
      if (
        result == FunctionsResponse.FulfillResult.FULFILLED
          || result == FunctionsResponse.FulfillResult.USER_CALLBACK_ERROR
      ) {
        emit OracleResponse(requestIds[i], msg.sender);
      }
    }
  }

  /// @dev Used in FunctionsBilling.sol
  function _onlyOwner() internal view override {
    _validateOwnership();
  }
}