// SPDX-License-Identifier: Apache-2.0.
pragma solidity ^0.8.24;

import {LibDiamond} from "./libraries/LibDiamond.sol";
import {IDiamondCut} from "./interfaces/IDiamondCut.sol";

contract Diamond {
  constructor(address _contractOwner, address _diamondCutFacet) payable {
    LibDiamond.setContractOwner(_contractOwner);

    // Add the diamondCut external function from the diamondCutFacet
    IDiamondCut.FacetCut[] memory cut = new IDiamondCut.FacetCut[](1);
    bytes4[] memory functionSelectors = new bytes4[](1);
    functionSelectors[0] = IDiamondCut.diamondCut.selector;
    cut[0] = IDiamondCut.FacetCut({
      facetAddress: _diamondCutFacet,
      action: IDiamondCut.FacetCutAction.Add,
      functionSelectors: functionSelectors
    });
    LibDiamond.diamondCut(cut, address(0), "");
  }

  // Find facet for function that is called and execute the
  // function if a facet is found and return any value.
  fallback() external payable {
    LibDiamond.DiamondStorage storage ds;
    bytes32 position = LibDiamond.DIAMOND_STORAGE_POSITION;
    // get diamond storage
    assembly {
      ds.slot := position
    }
    // get facet from function selector
    address facet = ds.selectorToFacetAndPosition[msg.sig].facetAddress;
    require(facet != address(0), "Diamond: Function does not exist");
    // Execute external function from facet using delegatecall and return any value.
    assembly {
      // copy function selector and any arguments
      calldatacopy(0, 0, calldatasize())
      // execute function call using the facet
      let result := delegatecall(gas(), facet, 0, calldatasize(), 0, 0)
      // get any return value
      returndatacopy(0, 0, returndatasize())
      // return any return value or error back to the caller
      switch result
      case 0 {
        revert(0, returndatasize())
      }
      default {
        return(0, returndatasize())
      }
    }
  }

  receive() external payable {}
}

// SPDX-License-Identifier: Apache-2.0.
pragma solidity ^0.8.24;

/******************************************************************************\
* Author: Nick Mudge <nick@perfectabstractions.com> (https://twitter.com/mudgen)
* EIP-2535 Diamonds: https://eips.ethereum.org/EIPS/eip-2535
/******************************************************************************/

interface IDiamondCut {
  enum FacetCutAction {
    Add,
    Replace,
    Remove
  }
  // Add=0, Replace=1, Remove=2

  struct FacetCut {
    address facetAddress;
    FacetCutAction action;
    bytes4[] functionSelectors;
  }

  /// @notice Add/replace/remove any number of functions and optionally execute
  ///         a function with delegatecall
  /// @param _diamondCut Contains the facet addresses and function selectors
  /// @param _init The address of the contract or facet to execute _calldata
  /// @param _calldata A function call, including function selector and arguments
  ///                  _calldata is executed with delegatecall on _init
  function diamondCut(
    FacetCut[] calldata _diamondCut,
    address _init,
    bytes calldata _calldata
  ) external;

  event DiamondCut(FacetCut[] _diamondCut, address _init, bytes _calldata);
}

// SPDX-License-Identifier: Apache-2.0.
pragma solidity ^0.8.24;

/******************************************************************************\
* Author: Nick Mudge <nick@perfectabstractions.com> (https://twitter.com/mudgen)
* EIP-2535 Diamonds: https://eips.ethereum.org/EIPS/eip-2535
/******************************************************************************/
import {IDiamondCut} from "../interfaces/IDiamondCut.sol";

// Remember to add the loupe functions from DiamondLoupeFacet to the diamond.
// The loupe functions are required by the EIP2535 Diamonds standard

error InitializationFunctionReverted(
  address _initializationContractAddress,
  bytes _calldata
);

library LibDiamond {
  bytes32 constant DIAMOND_STORAGE_POSITION =
    keccak256("diamond.standard.diamond.storage");

  struct FacetAddressAndPosition {
    address facetAddress;
    uint96 functionSelectorPosition; // position in facetFunctionSelectors.functionSelectors array
  }

  struct FacetFunctionSelectors {
    bytes4[] functionSelectors;
    uint256 facetAddressPosition; // position of facetAddress in facetAddresses array
  }

  struct DiamondStorage {
    // maps function selector to the facet address and
    // the position of the selector in the facetFunctionSelectors.selectors array
    mapping(bytes4 => FacetAddressAndPosition) selectorToFacetAndPosition;
    // maps facet addresses to function selectors
    mapping(address => FacetFunctionSelectors) facetFunctionSelectors;
    // facet addresses
    address[] facetAddresses;
    // Used to query if a contract implements an interface.
    // Used to implement ERC-165.
    mapping(bytes4 => bool) supportedInterfaces;
    // owner of the contract
    address contractOwner;
  }

  function diamondStorage() internal pure returns (DiamondStorage storage ds) {
    bytes32 position = DIAMOND_STORAGE_POSITION;
    assembly {
      ds.slot := position
    }
  }

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

  function setContractOwner(address _newOwner) internal {
    DiamondStorage storage ds = diamondStorage();
    address previousOwner = ds.contractOwner;
    ds.contractOwner = _newOwner;
    emit OwnershipTransferred(previousOwner, _newOwner);
  }

  function contractOwner() internal view returns (address contractOwner_) {
    contractOwner_ = diamondStorage().contractOwner;
  }

  function enforceIsContractOwner() internal view {
    require(
      msg.sender == diamondStorage().contractOwner,
      "LibDiamond: Must be contract owner"
    );
  }

  event DiamondCut(
    IDiamondCut.FacetCut[] _diamondCut,
    address _init,
    bytes _calldata
  );

  // Internal function version of diamondCut
  function diamondCut(
    IDiamondCut.FacetCut[] memory _diamondCut,
    address _init,
    bytes memory _calldata
  ) internal {
    for (uint256 facetIndex; facetIndex < _diamondCut.length; facetIndex++) {
      IDiamondCut.FacetCutAction action = _diamondCut[facetIndex].action;
      if (action == IDiamondCut.FacetCutAction.Add) {
        addFunctions(
          _diamondCut[facetIndex].facetAddress,
          _diamondCut[facetIndex].functionSelectors
        );
      } else if (action == IDiamondCut.FacetCutAction.Replace) {
        replaceFunctions(
          _diamondCut[facetIndex].facetAddress,
          _diamondCut[facetIndex].functionSelectors
        );
      } else if (action == IDiamondCut.FacetCutAction.Remove) {
        removeFunctions(
          _diamondCut[facetIndex].facetAddress,
          _diamondCut[facetIndex].functionSelectors
        );
      } else {
        revert("LibDiamondCut: Incorrect FacetCutAction");
      }
    }
    emit DiamondCut(_diamondCut, _init, _calldata);
    initializeDiamondCut(_init, _calldata);
  }

  function addFunctions(
    address _facetAddress,
    bytes4[] memory _functionSelectors
  ) internal {
    require(
      _functionSelectors.length > 0,
      "LibDiamondCut: No selectors in facet to cut"
    );
    DiamondStorage storage ds = diamondStorage();
    require(
      _facetAddress != address(0),
      "LibDiamondCut: Add facet can't be address(0)"
    );
    uint96 selectorPosition = uint96(
      ds.facetFunctionSelectors[_facetAddress].functionSelectors.length
    );
    // add new facet address if it does not exist
    if (selectorPosition == 0) {
      addFacet(ds, _facetAddress);
    }
    for (
      uint256 selectorIndex;
      selectorIndex < _functionSelectors.length;
      selectorIndex++
    ) {
      bytes4 selector = _functionSelectors[selectorIndex];
      address oldFacetAddress = ds
        .selectorToFacetAndPosition[selector]
        .facetAddress;
      require(
        oldFacetAddress == address(0),
        "LibDiamondCut: Can't add function that already exists"
      );
      addFunction(ds, selector, selectorPosition, _facetAddress);
      selectorPosition++;
    }
  }

  function replaceFunctions(
    address _facetAddress,
    bytes4[] memory _functionSelectors
  ) internal {
    require(
      _functionSelectors.length > 0,
      "LibDiamondCut: No selectors in facet to cut"
    );
    DiamondStorage storage ds = diamondStorage();
    require(
      _facetAddress != address(0),
      "LibDiamondCut: Add facet can't be address(0)"
    );
    uint96 selectorPosition = uint96(
      ds.facetFunctionSelectors[_facetAddress].functionSelectors.length
    );
    // add new facet address if it does not exist
    if (selectorPosition == 0) {
      addFacet(ds, _facetAddress);
    }
    for (
      uint256 selectorIndex;
      selectorIndex < _functionSelectors.length;
      selectorIndex++
    ) {
      bytes4 selector = _functionSelectors[selectorIndex];
      address oldFacetAddress = ds
        .selectorToFacetAndPosition[selector]
        .facetAddress;
      require(
        oldFacetAddress != _facetAddress,
        "LibDiamondCut: Can't replace function with same function"
      );
      removeFunction(ds, oldFacetAddress, selector);
      addFunction(ds, selector, selectorPosition, _facetAddress);
      selectorPosition++;
    }
  }

  function removeFunctions(
    address _facetAddress,
    bytes4[] memory _functionSelectors
  ) internal {
    require(
      _functionSelectors.length > 0,
      "LibDiamondCut: No selectors in facet to cut"
    );
    DiamondStorage storage ds = diamondStorage();
    // if function does not exist then do nothing and return
    require(
      _facetAddress == address(0),
      "LibDiamondCut: Remove facet address must be address(0)"
    );
    for (
      uint256 selectorIndex;
      selectorIndex < _functionSelectors.length;
      selectorIndex++
    ) {
      bytes4 selector = _functionSelectors[selectorIndex];
      address oldFacetAddress = ds
        .selectorToFacetAndPosition[selector]
        .facetAddress;
      removeFunction(ds, oldFacetAddress, selector);
    }
  }

  function addFacet(DiamondStorage storage ds, address _facetAddress) internal {
    enforceHasContractCode(
      _facetAddress,
      "LibDiamondCut: New facet has no code"
    );
    ds.facetFunctionSelectors[_facetAddress].facetAddressPosition = ds
      .facetAddresses
      .length;
    ds.facetAddresses.push(_facetAddress);
  }

  function addFunction(
    DiamondStorage storage ds,
    bytes4 _selector,
    uint96 _selectorPosition,
    address _facetAddress
  ) internal {
    ds
      .selectorToFacetAndPosition[_selector]
      .functionSelectorPosition = _selectorPosition;
    ds.facetFunctionSelectors[_facetAddress].functionSelectors.push(_selector);
    ds.selectorToFacetAndPosition[_selector].facetAddress = _facetAddress;
  }

  function removeFunction(
    DiamondStorage storage ds,
    address _facetAddress,
    bytes4 _selector
  ) internal {
    require(
      _facetAddress != address(0),
      "LibDiamondCut: Can't remove function that doesn't exist"
    );
    // an immutable function is a function defined directly in a diamond
    require(
      _facetAddress != address(this),
      "LibDiamondCut: Can't remove immutable function"
    );
    // replace selector with last selector, then delete last selector
    uint256 selectorPosition = ds
      .selectorToFacetAndPosition[_selector]
      .functionSelectorPosition;
    uint256 lastSelectorPosition = ds
      .facetFunctionSelectors[_facetAddress]
      .functionSelectors
      .length - 1;
    // if not the same then replace _selector with lastSelector
    if (selectorPosition != lastSelectorPosition) {
      bytes4 lastSelector = ds
        .facetFunctionSelectors[_facetAddress]
        .functionSelectors[lastSelectorPosition];
      ds.facetFunctionSelectors[_facetAddress].functionSelectors[
        selectorPosition
      ] = lastSelector;
      ds
        .selectorToFacetAndPosition[lastSelector]
        .functionSelectorPosition = uint96(selectorPosition);
    }
    // delete the last selector
    ds.facetFunctionSelectors[_facetAddress].functionSelectors.pop();
    delete ds.selectorToFacetAndPosition[_selector];

    // if no more selectors for facet address then delete the facet address
    if (lastSelectorPosition == 0) {
      // replace facet address with last facet address and delete last facet address
      uint256 lastFacetAddressPosition = ds.facetAddresses.length - 1;
      uint256 facetAddressPosition = ds
        .facetFunctionSelectors[_facetAddress]
        .facetAddressPosition;
      if (facetAddressPosition != lastFacetAddressPosition) {
        address lastFacetAddress = ds.facetAddresses[lastFacetAddressPosition];
        ds.facetAddresses[facetAddressPosition] = lastFacetAddress;
        ds
          .facetFunctionSelectors[lastFacetAddress]
          .facetAddressPosition = facetAddressPosition;
      }
      ds.facetAddresses.pop();
      delete ds.facetFunctionSelectors[_facetAddress].facetAddressPosition;
    }
  }

  function initializeDiamondCut(
    address _init,
    bytes memory _calldata
  ) internal {
    if (_init == address(0)) {
      return;
    }
    enforceHasContractCode(_init, "LibDiamondCut: _init address has no code");
    (bool success, bytes memory error) = _init.delegatecall(_calldata);
    if (!success) {
      if (error.length > 0) {
        // bubble up error
        /// @solidity memory-safe-assembly
        assembly {
          let returndata_size := mload(error)
          revert(add(32, error), returndata_size)
        }
      } else {
        revert InitializationFunctionReverted(_init, _calldata);
      }
    }
  }

  function enforceHasContractCode(
    address _contract,
    string memory _errorMessage
  ) internal view {
    uint256 contractSize;
    assembly {
      contractSize := extcodesize(_contract)
    }
    require(contractSize > 0, _errorMessage);
  }
}

{
  "compilationTarget": {
    "contracts/Diamond.sol": "Diamond"
  },
  "evmVersion": "paris",
  "libraries": {},
  "metadata": {
    "bytecodeHash": "ipfs"
  },
  "optimizer": {
    "enabled": false,
    "runs": 200
  },
  "remappings": []
}