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

import "@openzeppelin/contracts/access/AccessControl.sol";
import "./interfaces/IISO20022Router.sol";
import "./interfaces/IRailTriggerRegistry.sol";
import "./libraries/RailTypes.sol";
import "./libraries/ISO20022Types.sol";

/**
 * @title ISO20022Router
 * @notice Normalizes ISO-20022 messages into canonical on-chain format
 * @dev Creates triggers in RailTriggerRegistry for both inbound and outbound messages
 */
contract ISO20022Router is IISO20022Router, AccessControl {
    bytes32 public constant RAIL_OPERATOR_ROLE = keccak256("RAIL_OPERATOR_ROLE");

    IRailTriggerRegistry public immutable triggerRegistry;
    mapping(bytes32 => uint256) private _triggerIdByInstructionId; // instructionId => triggerId

    /**
     * @notice Initializes the router with registry address
     * @param admin Address that will receive DEFAULT_ADMIN_ROLE
     * @param triggerRegistry_ Address of RailTriggerRegistry contract
     */
    constructor(address admin, address triggerRegistry_) {
        _grantRole(DEFAULT_ADMIN_ROLE, admin);
        require(triggerRegistry_ != address(0), "ISO20022Router: zero triggerRegistry");
        triggerRegistry = IRailTriggerRegistry(triggerRegistry_);
    }

    /**
     * @notice Submits an inbound ISO-20022 message (rail confirmation/notification)
     * @dev Requires RAIL_OPERATOR_ROLE. Creates a trigger in CREATED state.
     * @param m Canonical message struct
     * @return triggerId The created trigger ID
     */
    function submitInbound(
        CanonicalMessage calldata m
    ) external override onlyRole(RAIL_OPERATOR_ROLE) returns (uint256 triggerId) {
        require(m.msgType != bytes32(0), "ISO20022Router: zero msgType");
        require(m.instructionId != bytes32(0), "ISO20022Router: zero instructionId");
        require(m.accountRefId != bytes32(0), "ISO20022Router: zero accountRefId");
        require(m.token != address(0), "ISO20022Router: zero token");
        require(m.amount > 0, "ISO20022Router: zero amount");

        // Determine rail from message type (simplified - in production, this would be more sophisticated)
        RailTypes.Rail rail = _determineRailFromMessageType(m.msgType);

        // Create trigger
        IRailTriggerRegistry.Trigger memory trigger = IRailTriggerRegistry.Trigger({
            id: 0, // Will be assigned by registry
            rail: rail,
            msgType: m.msgType,
            accountRefId: m.accountRefId,
            walletRefId: bytes32(0), // Will be resolved by orchestrator if needed
            token: m.token,
            amount: m.amount,
            currencyCode: m.currencyCode,
            instructionId: m.instructionId,
            state: RailTypes.State.CREATED,
            createdAt: 0, // Will be set by registry
            updatedAt: 0 // Will be set by registry
        });

        triggerId = triggerRegistry.createTrigger(trigger);
        _triggerIdByInstructionId[m.instructionId] = triggerId;

        emit InboundSubmitted(triggerId, m.msgType, m.instructionId, m.accountRefId);
    }

    /**
     * @notice Submits an outbound ISO-20022 message (rail initiation)
     * @dev Requires RAIL_OPERATOR_ROLE. Creates a trigger in CREATED state.
     * @param m Canonical message struct
     * @return triggerId The created trigger ID
     */
    function submitOutbound(
        CanonicalMessage calldata m
    ) external override onlyRole(RAIL_OPERATOR_ROLE) returns (uint256 triggerId) {
        require(m.msgType != bytes32(0), "ISO20022Router: zero msgType");
        require(m.instructionId != bytes32(0), "ISO20022Router: zero instructionId");
        require(m.accountRefId != bytes32(0), "ISO20022Router: zero accountRefId");
        require(m.token != address(0), "ISO20022Router: zero token");
        require(m.amount > 0, "ISO20022Router: zero amount");

        // Determine rail from message type
        RailTypes.Rail rail = _determineRailFromMessageType(m.msgType);

        // Create trigger
        IRailTriggerRegistry.Trigger memory trigger = IRailTriggerRegistry.Trigger({
            id: 0, // Will be assigned by registry
            rail: rail,
            msgType: m.msgType,
            accountRefId: m.accountRefId,
            walletRefId: bytes32(0), // Will be resolved by orchestrator if needed
            token: m.token,
            amount: m.amount,
            currencyCode: m.currencyCode,
            instructionId: m.instructionId,
            state: RailTypes.State.CREATED,
            createdAt: 0, // Will be set by registry
            updatedAt: 0 // Will be set by registry
        });

        triggerId = triggerRegistry.createTrigger(trigger);
        _triggerIdByInstructionId[m.instructionId] = triggerId;

        emit OutboundSubmitted(triggerId, m.msgType, m.instructionId, m.accountRefId);
    }

    /**
     * @notice Returns the trigger ID for a given instruction ID
     * @param instructionId The instruction ID
     * @return The trigger ID (0 if not found)
     */
    function getTriggerIdByInstructionId(bytes32 instructionId) external view override returns (uint256) {
        return _triggerIdByInstructionId[instructionId];
    }

    /**
     * @notice Determines the rail type from an ISO-20022 message type
     * @dev Simplified implementation - in production, this would use a mapping table
     * @param msgType The message type
     * @return The rail type
     */
    function _determineRailFromMessageType(bytes32 msgType) internal pure returns (RailTypes.Rail) {
        // This is a simplified implementation
        // In production, you would have a mapping table or more sophisticated logic
        // For now, we'll use a default based on message family
        if (msgType == ISO20022Types.PAIN_001 || msgType == ISO20022Types.PACS_008) {
            // These are commonly used across rails, default to SWIFT
            return RailTypes.Rail.SWIFT;
        }
        // Default to SWIFT for unknown types
        return RailTypes.Rail.SWIFT;
    }
}