// File: Diamond.sol



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

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

import {LibDiamond} from "LibDiamond.sol";
import {IDiamondCut} from "IDiamondCut.sol";
import {IERC1155} from "IERC1155.sol";
import {IERC165} from "IERC165.sol";

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

        LibDiamond.DiamondStorage storage ds = LibDiamond.diamondStorage();
        ds.supportedInterfaces[type(IERC1155).interfaceId] = true;

        // 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), "");

        //Add the IERC165.supportsInterface function
        functionSelectors[0] = IERC165.supportsInterface.selector;
        cut[0] = IDiamondCut.FacetCut({
            facetAddress: _diamondLoupeFacet,
            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 {}
}

// File: IDiamondCut.sol



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

interface IDiamondCut {
  enum FacetCutAction {
    Add,
    Replace,
    Remove
  }

  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);
}

// File: IERC1155.sol



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

import {IERC1155Internal} from "IERC1155Internal.sol";
import {IERC165} from "IERC165.sol";

/**
 * @title ERC1155 interface
 * @dev see https://github.com/ethereum/EIPs/issues/1155
 */
interface IERC1155 is IERC1155Internal, IERC165 {
    /**
     * @notice query the balance of given token held by given address
     * @param account address to query
     * @param id token to query
     * @return token balance
     */
    function balanceOf(address account, uint256 id)
        external
        view
        returns (uint256);

    /**
     * @notice query the balances of given tokens held by given addresses
     * @param accounts addresss to query
     * @param ids tokens to query
     * @return token balances
     */
    function balanceOfBatch(address[] calldata accounts, uint256[] calldata ids)
        external
        view
        returns (uint256[] memory);

    /**
     * @notice query approval status of given operator with respect to given address
     * @param account address to query for approval granted
     * @param operator address to query for approval received
     * @return whether operator is approved to spend tokens held by account
     */
    function isApprovedForAll(address account, address operator)
        external
        view
        returns (bool);

    /**
     * @notice grant approval to or revoke approval from given operator to spend held tokens
     * @param operator address whose approval status to update
     * @param status whether operator should be considered approved
     */
    function setApprovalForAll(address operator, bool status) external;

    /**
     * @notice transfer tokens between given addresses, checking for ERC1155Receiver implementation if applicable
     * @param from sender of tokens
     * @param to receiver of tokens
     * @param id token ID
     * @param amount quantity of tokens to transfer
     * @param data data payload
     */
    function safeTransferFrom(
        address from,
        address to,
        uint256 id,
        uint256 amount,
        bytes calldata data
    ) external;

    /**
     * @notice transfer batch of tokens between given addresses, checking for ERC1155Receiver implementation if applicable
     * @param from sender of tokens
     * @param to receiver of tokens
     * @param ids list of token IDs
     * @param amounts list of quantities of tokens to transfer
     * @param data data payload
     */
    function safeBatchTransferFrom(
        address from,
        address to,
        uint256[] calldata ids,
        uint256[] calldata amounts,
        bytes calldata data
    ) external;
}

// File: IERC1155Internal.sol



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

import {IERC165} from "IERC165.sol";

/**
 * @title Partial ERC1155 interface needed by internal functions
 */
interface IERC1155Internal {
    event TransferSingle(
        address indexed operator,
        address indexed from,
        address indexed to,
        uint256 id,
        uint256 value
    );

    event TransferBatch(
        address indexed operator,
        address indexed from,
        address indexed to,
        uint256[] ids,
        uint256[] values
    );

    event ApprovalForAll(
        address indexed account,
        address indexed operator,
        bool approved
    );
}

// File: IERC165.sol



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

/**
 * @title ERC165 interface registration interface
 * @dev see https://eips.ethereum.org/EIPS/eip-165
 */
interface IERC165 {
  /**
   * @notice query whether contract has registered support for given interface
   * @param interfaceId interface id
   * @return bool whether interface is supported
   */
  function supportsInterface(bytes4 interfaceId) external view returns (bool);
}

// File: LibDiamond.sol



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

import {IDiamondCut} from "IDiamondCut.sol";

library LibDiamond {
    bytes32 internal constant DIAMOND_STORAGE_POSITION =
        keccak256("komon.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; ) {
            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");
            }
            unchecked {
                facetIndex++;
            }
        }
        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;

        ) {
            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++;
            unchecked {
                selectorIndex++;
            }
        }
    }

    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;

        ) {
            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++;
            unchecked {
                selectorIndex++;
            }
        }
    }

    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;

        ) {
            bytes4 selector = _functionSelectors[selectorIndex];
            address oldFacetAddress = ds
                .selectorToFacetAndPosition[selector]
                .facetAddress;
            removeFunction(ds, oldFacetAddress, selector);
            unchecked {
                selectorIndex++;
            }
        }
    }

    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)) {
            require(
                _calldata.length == 0,
                "LibDiamondCut: _init is address(0) but_calldata is not empty"
            );
        } else {
            require(
                _calldata.length > 0,
                "LibDiamondCut: _calldata is empty but _init is not address(0)"
            );
            if (_init != address(this)) {
                enforceHasContractCode(
                    _init,
                    "LibDiamondCut: _init address has no code"
                );
            }
            (bool success, bytes memory error) = _init.delegatecall(_calldata);
            if (!success) {
                if (error.length > 0) {
                    // bubble up the error
                    revert(string(error));
                } else {
                    revert("LibDiamondCut: _init function reverted");
                }
            }
        }
    }

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