import { CommunicationRequest, Communication } from 'fhir/r4';
import { useWebSocketServiceContext } from '../services';
import { useEffect } from 'react';

interface UseFhirCommunicationRequestTargetedBroadcastOptions {
    communicationRequest?: CommunicationRequest;
    communicationRequestId?: string;
    threadId?: string; // NEW
    isOpen?: boolean;
    onUpdate: (communicationRequest: CommunicationRequest) => void;
    onDelete: () => void;
    onMessageUpdate?: (communication: Communication) => void; // NEW
}

export const useFhirCommunicationRequestTargetedBroadcast = ({
    communicationRequest,
    communicationRequestId,
    threadId,
    isOpen = true,
    onUpdate,
    onDelete,
    onMessageUpdate
}: UseFhirCommunicationRequestTargetedBroadcastOptions) => {
    const { subscribe, unsubscribe } = useWebSocketServiceContext();

    useEffect(() => {
        if ((!communicationRequest && !threadId) || !isOpen) {
            return;
        }

        const targetRequestId = communicationRequestId || communicationRequest?.id;

        const handleCommunicationRequestEvent = (cloudEvent: any) => {
            const payload: CommunicationRequest = cloudEvent.data;
            const eventType = cloudEvent.type;

            if (payload.id === targetRequestId) {
                switch (eventType) {
                    case 'com.akashichealthrecords.fhir.communicationrequest.updated':
                        onUpdate(payload);
                        break;
                    case 'com.akashichealthrecords.fhir.communicationrequest.deleted':
                        onDelete();
                        break;
                }
            }
        };

        const handleCommunicationEvent = (cloudEvent: any) => {
            if (!onMessageUpdate) return;

            const payload: Communication = cloudEvent.data;

            // thread-first detection
            const basedOnRef = payload.basedOn?.[0]?.reference;

            let messageThreadId: string | null = null;

            if (basedOnRef?.startsWith('Thread/')) {
                messageThreadId = basedOnRef.split('/')[1];
            } else if (basedOnRef && threadId) {
                // fallback
                messageThreadId = threadId;
            }

            if (messageThreadId && threadId && messageThreadId === threadId) {
                onMessageUpdate(payload);
            }
        };

        // legacy subscriptions
        subscribe('com.akashichealthrecords.fhir.communicationrequest.updated', handleCommunicationRequestEvent);
        subscribe('com.akashichealthrecords.fhir.communicationrequest.deleted', handleCommunicationRequestEvent);

        // NEW thread-aware message events
        subscribe('com.akashichealthrecords.fhir.communication.created', handleCommunicationEvent);
        subscribe('com.akashichealthrecords.fhir.communication.updated', handleCommunicationEvent);

        return () => {
            unsubscribe('com.akashichealthrecords.fhir.communicationrequest.updated', handleCommunicationRequestEvent);
            unsubscribe('com.akashichealthrecords.fhir.communicationrequest.deleted', handleCommunicationRequestEvent);

            unsubscribe('com.akashichealthrecords.fhir.communication.created', handleCommunicationEvent);
            unsubscribe('com.akashichealthrecords.fhir.communication.updated', handleCommunicationEvent);
        };
    }, [
        communicationRequest,
        communicationRequestId,
        threadId,
        isOpen,
        onUpdate,
        onDelete,
        onMessageUpdate,
        subscribe,
        unsubscribe
    ]);
};