[ERC7794] 複数チェーン上の助成金の管理・追跡を行う仕組みを理解しよう！

function registerGrant(
    uint256 id,
    uint256 chainid,
    string memory community,
    address grantManager
) external returns (bytes32);

function transferOwnership(bytes32 grantId, address newGrantManager) external;

function addGrantee(bytes32 grantId, address grantee) external;

function removeGrantee(bytes32 grantId, address grantee) external;

function setStartDate(bytes32 grantId, uint256 startDate) external;

function addMilestoneDate(bytes32 grantId, uint256 milestoneDate) external;

function addDisbursement(
    bytes32 grantId,
    uint256 milestoneDate,
    address fundingToken,
    uint256 fundingAmount
) external;

function removeDisbursement(bytes32 grantId, uint256 milestoneDate) external;

function setDisbursementStatus(
    bytes32 grantId,
    uint256 milestoneDate,
    bool isDisbursed
) external;

function addExternalLink(bytes32 grantId, string memory link) external;

function removeExternalLink(bytes32 grantId, uint256 index) external;

function getGrant(bytes32 grantId) external view returns (Grant memory);

function getGrantManager(bytes32 grantId) external view returns (address);

function getGrantees(bytes32 grantId) external view returns (address[] memory);

function getMilestonesDates(bytes32 grantId) external view returns (uint256, uint256[] memory);

function getDisbursement(bytes32 grantId, uint256 milestoneDate) external view returns (Disbursements memory);

function getExternalLinks(bytes32 grantId) external view returns (string[] memory);

// SPDX-License-Identifier: CC0-1.0
pragma solidity ^0.8.20;

interface IGrantRegistry {
  /**
   * @dev Thrown when the community name length is invalid (e.g., too short or too long).
   */
  error InvalidCommunityNameLength();

  /**
   * @dev Thrown when the caller is not the current grant manager.
   */
  error InvalidGrantManager();

  /**
   * @dev Thrown when a grant is already registered with the provided ID.
   */
  error GrantAlreadyRegistered();

  /**
   * @dev Thrown when attempting to add a grantee that is already present in the set.
   */
  error GranteeAlreadyAdded();

  /**
   * @dev Thrown when attempting to remove a grantee that is not found in the set.
   */
  error GranteeNotFound();

  /**
   * @dev Thrown when attempting to add or reference an invalid external link.
   */
  error InvalidExternalLink();

  /**
   * @dev Thrown when an invalid index is provided (e.g., out of bounds for an array).
   */
  error InvalidIndex();

  /**
   * @dev Thrown when a milestone date is invalid (e.g., earlier than the grant's start date).
   */
  error InvalidStartDate();

  /**
   * @dev Thrown when attempting to add a milestone date that is already present.
   */
  error MilestoneDateAlreadyAdded();

  /**
   * @dev Thrown when attempting to remove or reference a milestone date that is not found.
   */
  error MilestoneDateNotFound();

  /**
   * @dev Emitted when a new grant is registered.
   * @param grantId The unique identifier for the grant.
   * @param id The grant's unique numeric ID.
   * @param chainid The chain ID where the grant is registered.
   * @param community The name of the community that issued the grant.
   * @param grantManager The address of the grant manager.
   */
  event GrantRegistered(
    bytes32 indexed grantId,
    uint256 indexed id,
    uint256 chainid,
    string indexed community,
    address grantManager
  );

  /**
   * @dev Emitted when the ownership of a grant is transferred.
   * @param grantId The unique identifier of the grant.
   * @param newGrantManager The address of the new grant manager.
   */
  event OwnershipTransferred(
    bytes32 indexed grantId,
    address indexed newGrantManager
  );

  /**
   * @dev Emitted when a new grantee is added to the grant.
   * @param grantId The unique identifier of the grant.
   * @param grantee The address of the new grantee.
   */
  event GranteeAdded(bytes32 indexed grantId, address indexed grantee);

  /**
   * @dev Emitted when a grantee is removed from the grant.
   * @param grantId The unique identifier of the grant.
   * @param grantee The address of the removed grantee.
   */
  event GranteeRemoved(bytes32 indexed grantId, address indexed grantee);

  /**
   * @dev Emitted when the start date of a grant is set.
   * @param grantId The unique identifier of the grant.
   * @param startDate The timestamp representing the start date.
   */
  event StartDateSet(bytes32 indexed grantId, uint256 startDate);

  /**
   * @dev Emitted when a new milestone date is added to the grant.
   * @param grantId The unique identifier of the grant.
   * @param milestoneDate The timestamp of the added milestone.
   */
  event MilestoneDateAdded(bytes32 indexed grantId, uint256 milestoneDate);

  /**
   * @dev Emitted when a milestone date is removed from the grant.
   * @param grantId The unique identifier of the grant.
   * @param milestoneDate The timestamp of the removed milestone.
   */
  event MilestoneDateRemoved(bytes32 indexed grantId, uint256 milestoneDate);

  /**
   * @dev Emitted when a disbursement is added to a milestone.
   * @param grantId The unique identifier of the grant.
   * @param milestoneDate The timestamp of the milestone.
   * @param fundingToken The token used for the disbursement.
   * @param fundingAmount The amount of the disbursement.
   */
  event DisbursementAdded(
    bytes32 indexed grantId,
    uint256 milestoneDate,
    address indexed fundingToken,
    uint256 fundingAmount
  );

  /**
   * @dev Emitted when a disbursement is removed from a milestone.
   * @param grantId The unique identifier of the grant.
   * @param milestoneDate The timestamp of the milestone.
   */
  event DisbursementRemoved(bytes32 indexed grantId, uint256 milestoneDate);

  /**
   * @dev Emitted when a disbursement status is updated.
   * @param grantId The unique identifier of the grant.
   * @param milestoneDate The timestamp of the milestone.
   * @param isDisbursed Boolean indicating if the disbursement has been made.
   */
  event DisbursementMade(
    bytes32 indexed grantId,
    uint256 milestoneDate,
    bool isDisbursed
  );

  /**
   * @dev Emitted when an external link is added to the grant.
   * @param grantId The unique identifier of the grant.
   * @param link The external URL added.
   */
  event ExternalLinkAdded(bytes32 indexed grantId, string link);

  /**
   * @dev Emitted when an external link is removed from the grant.
   * @param grantId The unique identifier of the grant.
   * @param link The external URL removed.
   */
  event ExternalLinkRemoved(bytes32 indexed grantId, string link);

  /**
   * @dev Registers a new grant with the provided details. `grantId` is generated by hashing the grant
   * details and the current timestamp.
   *
   * Requirements:
   *
   * - The `grantManager` address must not be the zero address.
   * - The `community` name must not be empty.
   * - The grant must not already be registered.
   *
   * Emits a {GrantRegistered} event.
   *
   * @param id The unique identifier for the grant program.
   * @param chainid The chain ID where the grant is being registered.
   * @param community The name of the community or protocol issuing the grant.
   * @param grantManager The address of the grant manager.
   * @return The generated `grantId` as a bytes32 value.
   */
  function registerGrant(
    uint256 id,
    uint256 chainid,
    string memory community,
    address grantManager
  ) external returns (bytes32);

  /**
   * @dev Transfers ownership of the grant to a new grant manager.
   *
   * Requirements:
   *
   * - The caller must be the current grant manager.
   * - The `newGrantManager` address must not be the zero address.
   *
   * Emits an {OwnershipTransferred} event.
   *
   * @param grantId The unique identifier of the grant.
   * @param newGrantManager The address of the new grant manager.
   */
  function transferOwnership(bytes32 grantId, address newGrantManager) external;

  /**
   * @dev Adds a new grantee to the grant.
   *
   * Requirements:
   *
   * - The caller must be the current grant manager.
   * - The `grantee` address must not be the zero address.
   *
   * Emits a {GranteeAdded} event.
   *
   * @param grantId The unique identifier of the grant.
   * @param grantee The address of the grantee to be added.
   */
  function addGrantee(bytes32 grantId, address grantee) external;

  /**
   * @dev Removes an existing grantee from the grant.
   *
   * Requirements:
   *
   * - The caller must be the current grant manager.
   * - The `grantee` address must be present in the grant.
   *
   * Emits a {GranteeRemoved} event.
   *
   * @param grantId The unique identifier of the grant.
   * @param grantee The address of the grantee to be removed.
   */
  function removeGrantee(bytes32 grantId, address grantee) external;

  /**
   * @dev Sets the start date for the grant.
   *
   * Requirements:
   *
   * - The caller must be the current grant manager.
   *
   * Emits a {StartDateSet} event.
   *
   * @param grantId The unique identifier of the grant.
   * @param startDate The timestamp representing the start date.
   */
  function setStartDate(bytes32 grantId, uint256 startDate) external;

  /**
   * @dev Adds a new milestone date for the grant.
   *
   * Requirements:
   *
   * - The caller must be the current grant manager.
   * - The milestone date must not already exist in the grant.
   *
   * Emits a {MilestoneDateAdded} event.
   *
   * @param grantId The unique identifier of the grant.
   * @param milestoneDate The timestamp representing the milestone date.
   */
  function addMilestoneDate(bytes32 grantId, uint256 milestoneDate) external;

  /**
   * @dev Removes a milestone date from the grant.
   *
   * Requirements:
   *
   * - The caller must be the current grant manager.
   * - The milestone date must exist in the grant.
   *
   * Emits a {MilestoneDateRemoved} event.
   *
   * @param grantId The unique identifier of the grant.
   * @param milestoneDate The timestamp representing the milestone date to be removed.
   */
  function removeMilestoneDate(bytes32 grantId, uint256 milestoneDate) external;

  /**
   * @dev Ovewrites a disbursement for a specific milestone.
   *
   * Requirements:
   *
   * - The caller must be the current grant manager.
   * - The milestone date must exist in the grant.
   *
   * Emits a {DisbursementAdded} event.
   *
   * @param grantId The unique identifier of the grant.
   * @param milestoneDate The milestone date associated with the disbursement.
   * @param fundingToken The address of the token used for funding.
   * @param fundingAmount The amount of tokens to be disbursed.
   */
  function addDisbursement(
    bytes32 grantId,
    uint256 milestoneDate,
    address fundingToken,
    uint256 fundingAmount
  ) external;

  /**
   * @dev Removes a disbursement for a specific milestone.
   *
   * Requirements:
   *
   * - The caller must be the current grant manager.
   * - The milestone date must exist in the grant.
   *
   * Emits a {DisbursementRemoved} event.
   *
   * @param grantId The unique identifier of the grant.
   * @param milestoneDate The milestone date associated with the disbursement.
   */
  function removeDisbursement(bytes32 grantId, uint256 milestoneDate) external;

  /**
   * @dev Updates the disbursement status for a specific milestone.
   *
   * Requirements:
   *
   * - The caller must be the current grant manager.
   * - The milestone date must exist in the grant.
   *
   * Emits a {DisbursementMade} event.
   *
   * @param grantId The unique identifier of the grant.
   * @param milestoneDate The milestone date associated with the disbursement.
   * @param isDisbursed A boolean value indicating if the disbursement has been made.
   */
  function setDisbursementStatus(
    bytes32 grantId,
    uint256 milestoneDate,
    bool isDisbursed
  ) external;

  /**
   * @dev Adds an external link related to the grant.
   *
   * Requirements:
   *
   * - The caller must be the current grant manager.
   * - The link must not be empty.
   *
   * Emits an {ExternalLinkAdded} event.
   *
   * @param grantId The unique identifier of the grant.
   * @param link The external URL to be added.
   */
  function addExternalLink(bytes32 grantId, string memory link) external;

  /**
   * @dev Removes an external link associated with the grant.
   *
   * Requirements:
   *
   * - The caller must be the current grant manager.
   * - The index must be within the bounds of the external links array.
   *
   * Emits an {ExternalLinkRemoved} event.
   *
   * @param grantId The unique identifier of the grant.
   * @param index The index of the external link to be removed.
   */
  function removeExternalLink(bytes32 grantId, uint256 index) external;

  /**
   * @dev Retrieves details of a specific grant by its ID
   * @param grantId The unique identifier of the grant
   * @return The `Grant` struct containing id, chainid, and community label
   */
  function getGrant(bytes32 grantId) external view returns (Grant memory);

  /**
   * @dev Retrieves the current grant manager for a specific grant
   * @param grantId The unique identifier of the grant
   * @return The address of the grant manager
   */
  function getGrantManager(bytes32 grantId) external view returns (address);

  /**
   * @dev Retrieves the list of grantees associated with a specific grant
   * @param grantId The unique identifier of the grant
   * @return An array of addresses representing the grantees
   */
  function getGrantees(
    bytes32 grantId
  ) external view returns (address[] memory);

  /**
   * @dev Retrieves the start date and list of milestone dates for a specific grant
   * @param grantId The unique identifier of the grant
   * @return The start date and an array of milestone dates
   */
  function getMilestonesDates(
    bytes32 grantId
  ) external view returns (uint256, uint256[] memory);

  /**
   * @dev Retrieves the disbursement details for a specific milestone in a grant
   * @param grantId The unique identifier of the grant
   * @param milestoneDate The date of the milestone for which disbursement details are requested
   * @return The `Disbursements` struct containing the token address, funding amount, and disbursement status
   */
  function getDisbursement(
    bytes32 grantId,
    uint256 milestoneDate
  ) external view returns (Disbursements memory);

  /**
   * @dev Retrieves the list of external links associated with a specific grant
   * @param grantId The unique identifier of the grant
   * @return An array of strings representing the external links
   */
  function getExternalLinks(
    bytes32 grantId
  ) external view returns (string[] memory);
}

// SPDX-License-Identifier: CC0-1.0
pragma solidity ^0.8.20;

import { IGrantRegistry } from "./IGrantRegistry.sol";
import { EnumerableSet } from "@openzeppelin/contracts/utils/structs/EnumerableSet.sol";

contract GrantRegistry is IGrantRegistry {
  using EnumerableSet for EnumerableSet.AddressSet;
  using EnumerableSet for EnumerableSet.UintSet;

  /**
   * @dev Mapping to store the details of each grant, keyed by its unique grantId.
   */
  mapping(bytes32 => Grant) private _grants;

  /**
   * @dev Stores information about the participants in each grant (manager and grantees), keyed by the grantId.
   * This mapping allows tracking of the grant manager and the associated grantees for each grant.
   */
  mapping(bytes32 => Participants) private _participants;

  /**
   * @dev Stores milestone-related data for each grant, keyed by the grantId.
   * This includes the start date, milestone dates, and disbursements related to each milestone.
   */
  mapping(bytes32 => Milestones) private _milestones;

  /**
   * @dev Stores external links related to each grant, such as proposal URLs or related documentation, keyed by grantId.
   * External links provide references to off-chain information about the grant.
   */
  mapping(bytes32 => string[]) private _externalLinks;

  /**
   * @dev See {IGrantRegistry-registerGrant}.
   */
  function registerGrant(
    uint256 id,
    uint256 chainid,
    string memory community,
    address grantManager
  ) external returns (bytes32) {
    bytes32 grantId = keccak256(
      abi.encodePacked(id, chainid, community, block.timestamp)
    );

    if (grantManager == address(0)) revert InvalidGrantManager();
    if (bytes(community).length == 0) revert InvalidCommunityNameLength();
    if (bytes(_grants[grantId].community).length > 0)
      revert GrantAlreadyRegistered();

    _grants[grantId] = Grant(id, chainid, community);
    _participants[grantId].grantManager = grantManager;

    emit GrantRegistered(grantId, id, chainid, community, grantManager);
    return grantId;
  }

  /**
   * @dev See {IGrantRegistry-transferOwnership}.
   */
  function transferOwnership(
    bytes32 grantId,
    address newGrantManager
  ) external {
    _requireManager(grantId);
    if (newGrantManager == address(0)) revert InvalidGrantManager();
    _participants[grantId].grantManager = newGrantManager;
    emit OwnershipTransferred(grantId, newGrantManager);
  }

  /**
   * @dev See {IGrantRegistry-addGrantee}.
   */
  function addGrantee(bytes32 grantId, address grantee) external {
    _requireManager(grantId);
    if (grantee == address(0)) revert InvalidGrantManager();
    bool success = _participants[grantId].grantees.add(grantee);
    if (!success) revert GranteeAlreadyAdded();
    emit GranteeAdded(grantId, grantee);
  }

  /**
   * @dev See {IGrantRegistry-removeGrantee}.
   */
  function removeGrantee(bytes32 grantId, address grantee) external {
    _requireManager(grantId);
    bool success = _participants[grantId].grantees.remove(grantee);
    if (!success) revert GranteeNotFound();
    emit GranteeRemoved(grantId, grantee);
  }

  /**
   * @dev See {IGrantRegistry-setStartDate}.
   */
  function setStartDate(bytes32 grantId, uint256 startDate) external {
    _requireManager(grantId);
    _milestones[grantId].startDate = startDate;
    emit StartDateSet(grantId, startDate);
  }

  /**
   * @dev See {IGrantRegistry-addMilestoneDate}.
   */
  function addMilestoneDate(bytes32 grantId, uint256 milestoneDate) external {
    _requireManager(grantId);
    bool success = _milestones[grantId].milestonesDates.add(milestoneDate);
    if (!success) revert MilestoneDateAlreadyAdded();
    emit MilestoneDateAdded(grantId, milestoneDate);
  }

  /**
   * @dev See {IGrantRegistry-removeMilestoneDate}.
   */
  function removeMilestoneDate(
    bytes32 grantId,
    uint256 milestoneDate
  ) external {
    _requireManager(grantId);
    bool success = _milestones[grantId].milestonesDates.remove(milestoneDate);
    if (!success) revert MilestoneDateNotFound();
    emit MilestoneDateRemoved(grantId, milestoneDate);
  }

  /**
   * @dev See {IGrantRegistry-addDisbursement}.
   */
  function addDisbursement(
    bytes32 grantId,
    uint256 milestoneDate,
    address fundingToken,
    uint256 fundingAmount
  ) external {
    _requireManager(grantId);
    _requireMilestoneDate(grantId, milestoneDate);
    _milestones[grantId].disbursements[milestoneDate] = Disbursements(
      fundingToken,
      fundingAmount,
      false
    );
    emit DisbursementAdded(grantId, milestoneDate, fundingToken, fundingAmount);
  }

  /**
   * @dev See {IGrantRegistry-removeDisbursement}.
   */
  function removeDisbursement(bytes32 grantId, uint256 milestoneDate) external {
    _requireManager(grantId);
    _requireMilestoneDate(grantId, milestoneDate);
    delete _milestones[grantId].disbursements[milestoneDate];
    emit DisbursementRemoved(grantId, milestoneDate);
  }

  /**
   * @dev See {IGrantRegistry-setDisbursementStatus}.
   */
  function setDisbursementStatus(
    bytes32 grantId,
    uint256 milestoneDate,
    bool isDisbursed
  ) external {
    _requireManager(grantId);
    _requireMilestoneDate(grantId, milestoneDate);
    _milestones[grantId].disbursements[milestoneDate].isDisbursed = isDisbursed;
    emit DisbursementMade(grantId, milestoneDate, isDisbursed);
  }

  /**
   * @dev See {IGrantRegistry-addExternalLink}.
   */
  function addExternalLink(bytes32 grantId, string memory link) external {
    _requireManager(grantId);
    if (bytes(link).length == 0) revert InvalidExternalLink();
    _externalLinks[grantId].push(link);
    emit ExternalLinkAdded(grantId, link);
  }

  /**
   * @dev See {IGrantRegistry-removeExternalLink}.
   */
  function removeExternalLink(bytes32 grantId, uint256 index) external {
    _requireManager(grantId);
    if (index >= _externalLinks[grantId].length) revert InvalidIndex();
    string memory link = _externalLinks[grantId][index];
    _externalLinks[grantId][index] = _externalLinks[grantId][
      _externalLinks[grantId].length - 1
    ];
    _externalLinks[grantId].pop();
    emit ExternalLinkRemoved(grantId, link);
  }

  /**
   * @dev Ensures that the caller is the grant manager for the given grantId.
   * Reverts with `InvalidGrantManager` if the caller is not the grant manager.
   * @param grantId The unique identifier of the grant being checked.
   */
  function _requireManager(bytes32 grantId) internal view {
    if (msg.sender != _participants[grantId].grantManager)
      revert InvalidGrantManager();
  }

  /**
   * @dev Ensures that the milestone date is present in the grant.
   * Reverts with `MilestoneDateNotFound` if the milestone date is not present.
   * @param grantId The unique identifier of the grant being checked.
   * @param milestoneDate The milestone date being checked.
   */
  function _requireMilestoneDate(
    bytes32 grantId,
    uint256 milestoneDate
  ) internal view {
    if (!_milestones[grantId].milestonesDates.contains(milestoneDate))
      revert MilestoneDateNotFound();
  }

  /**
   * @dev See {IGrantRegistry-getGrant}.
   */
  function getGrant(bytes32 grantId) external view returns (Grant memory) {
    return _grants[grantId];
  }

  /**
   * @dev See {IGrantRegistry-getGrantManager}.
   */
  function getGrantManager(bytes32 grantId) external view returns (address) {
    return _participants[grantId].grantManager;
  }

  /**
   * @dev See {IGrantRegistry-getGrantees}.
   */
  function getGrantees(
    bytes32 grantId
  ) external view returns (address[] memory) {
    return _participants[grantId].grantees.values();
  }

  /**
   * @dev See {IGrantRegistry-getMilestonesDates}.
   */
  function getMilestonesDates(
    bytes32 grantId
  ) external view returns (uint256, uint256[] memory) {
    return (
      _milestones[grantId].startDate,
      _milestones[grantId].milestonesDates.values()
    );
  }

  /**
   * @dev See {IGrantRegistry-getDisbursement}.
   */
  function getDisbursement(
    bytes32 grantId,
    uint256 milestoneDate
  ) external view returns (Disbursements memory) {
    return _milestones[grantId].disbursements[milestoneDate];
  }

  /**
   * @dev See {IGrantRegistry-getExternalLinks}.
   */
  function getExternalLinks(
    bytes32 grantId
  ) external view returns (string[] memory) {
    return _externalLinks[grantId];
  }
}