import { generations } from '~~/drizzle/schema';
import { db } from '~~/server/lib/db';
import { cancelPendingGeneration } from '~~/server/utils/generations';

export default defineEventHandler(async (event) => {
    await protectRoute(event);

    const { generationId } = event.context.params!;
    const topicId = getRouterParam(event, 'topicId')!;

    const topic = await db.query.topics.findFirst({
        where: {
            id: topicId,
            userId: event.context.user!.id as string,
        },
        with: {
            messages: true,
        },
    });

    if (!topic) throw createError({ statusCode: 404, message: 'Topic not found' });

    const success = cancelPendingGeneration(generationId!);

    const generation = await db.query.generations.findFirst({
        where: {
            id: generationId,
        },
    });

    if (!generation) {
        throw createError({
            statusCode: 404,
            message: 'Generation not found',
        });
    }

    if (generation.status === 'completed') {
        throw createError({
            statusCode: 400,
            message: 'Generation already completed',
        });
    }

    const message = await db.query.messages.findFirst({
        where: {
            generationId: generation.id,
        },
    });

    if (!message) {
        throw createError({
            statusCode: 404,
            message: 'Message not found',
        });
    }

    await db.update(generations).set({ status: 'cancelled' });
    await topicEvents.emit(topicId, {
        type: 'generation-complete',
        payload: {
            messageId: message.id,
            generationId,
        }
    })

    if (!success) {
        throw createError({
            statusCode: 400,
            message: 'Generation not found or already completed',
        });
    }

    return 'ok';
});