import { and, eq, sql } from 'drizzle-orm'
import { z } from 'zod'
import { threadSubscriptions, uploadReactions, uploads } from '../../../db/schema'

const bodySchema = z.object({
  emoji: z.string().min(1).max(32),
})

export default defineEventHandler(async (event) => {
  const user = await requireUser(event)
  const uploadId = getRouterParam(event, 'id') ?? ''
  const { emoji } = await readValidatedBody(event, bodySchema.parse)
  const db = useDb()

  const [upload] = await db
    .select({ id: uploads.id })
    .from(uploads)
    .where(eq(uploads.id, uploadId))
    .limit(1)
  if (!upload) {
    throw createError({ statusCode: 404, statusMessage: 'Upload nicht gefunden' })
  }

  const existing = await db
    .select({ userId: uploadReactions.userId })
    .from(uploadReactions)
    .where(and(
      eq(uploadReactions.uploadId, uploadId),
      eq(uploadReactions.userId, user.id),
      eq(uploadReactions.emoji, emoji),
    ))
    .limit(1)

  let active: boolean
  if (existing.length) {
    await db.delete(uploadReactions).where(and(
      eq(uploadReactions.uploadId, uploadId),
      eq(uploadReactions.userId, user.id),
      eq(uploadReactions.emoji, emoji),
    ))
    active = false
  }
  else {
    await db.transaction(async (tx) => {
      await tx.insert(uploadReactions).values({ uploadId, userId: user.id, emoji })
      await ensureThreadSubscription(uploadId, user.id, tx)
    })
    active = true
  }

  const [result] = await db
    .select({ total: sql<number>`count(*)` })
    .from(uploadReactions)
    .where(and(eq(uploadReactions.uploadId, uploadId), eq(uploadReactions.emoji, emoji)))
  const count = Number(result?.total ?? 0)

  broadcastToAll({
    type: 'upload-reaction',
    uploadId,
    emoji,
    actorId: user.id,
    actorName: user.name,
    active,
    count,
  })

  const [subscription] = await db.select({ enabled: threadSubscriptions.enabled }).from(threadSubscriptions)
    .where(and(eq(threadSubscriptions.uploadId, uploadId), eq(threadSubscriptions.userId, user.id))).limit(1)
  return { active, count, isSubscribed: subscription?.enabled ?? false }
})