import { asc, count, desc, eq, inArray } from 'drizzle-orm'
import { commentAttachments, comments, uploads, users } from '../../../db/schema'
import type { CommentAttachment } from '~~/shared/utils/attachments'

export default defineEventHandler(async (event) => {
  const idParam = getRouterParam(event, 'id') ?? ''
  if (!/^\d+$/.test(idParam)) {
    throw createError({ statusCode: 400, statusMessage: 'Ungültige Nutzer-ID' })
  }
  const userId = Number(idParam)

  const q = getQuery(event)
  const page = Math.max(1, Math.floor(Number(q.page)) || 1)
  const perPage = Math.min(100, Math.max(1, Math.floor(Number(q.perPage)) || 20))

  const db = useDb()
  const [user] = await db
    .select({ id: users.id })
    .from(users)
    .where(eq(users.id, userId))
    .limit(1)

  if (!user) {
    throw createError({ statusCode: 404, statusMessage: 'Nutzer nicht gefunden' })
  }

  const [totalRow, rows] = await Promise.all([
    db.select({ count: count() }).from(comments).where(eq(comments.userId, userId)),
    db
      .select({
      id: comments.id,
      content: comments.content,
      createdAt: comments.createdAt,
      uploadId: uploads.id,
      uploadType: uploads.type,
      uploadFileName: uploads.fileName,
      uploadExternalUrl: uploads.externalUrl,
      uploadPreviewImage: uploads.previewImage,
      })
      .from(comments)
      .innerJoin(uploads, eq(comments.uploadId, uploads.id))
      .where(eq(comments.userId, userId))
      .orderBy(desc(comments.createdAt))
      .limit(perPage)
      .offset((page - 1) * perPage),
  ])

  const total = totalRow[0]?.count ?? 0

  const commentIds = rows.map(r => r.id)
  const attachmentRows = commentIds.length
    ? await db
        .select()
        .from(commentAttachments)
        .where(inArray(commentAttachments.commentId, commentIds))
        .orderBy(asc(commentAttachments.id))
    : []
  const attachmentsByComment = new Map<number, CommentAttachment[]>()
  for (const a of attachmentRows) {
    let list = attachmentsByComment.get(a.commentId)
    if (!list) {
      list = []
      attachmentsByComment.set(a.commentId, list)
    }
    list.push({ id: a.id, name: a.originalName, url: `/uploads/attachments/${a.fileName}`, mimeType: a.mimeType, size: a.size, cover: a.cover, meta: a.meta as CommentAttachment['meta'] })
  }

  const items = rows.map((row) => {
    const url = row.uploadExternalUrl ?? `/uploads/${row.uploadFileName}`
    const embedId = row.uploadType === 'youtube' && row.uploadExternalUrl ? getYoutubeId(row.uploadExternalUrl) : null
    const uploadThumbUrl = row.uploadType === 'youtube' && embedId
      ? youtubeThumbUrl(embedId)
      : row.uploadType === 'image' ? url : row.uploadType === 'link' || row.uploadType === 'twitch' || row.uploadType === 'audio' ? row.uploadPreviewImage : null
    return {
      id: row.id,
      content: row.content,
      createdAt: row.createdAt,
      uploadId: row.uploadId,
      uploadThumbUrl,
      attachments: attachmentsByComment.get(row.id) ?? [],
    }
  })

  return { items, total, pageCount: Math.max(1, Math.ceil(total / perPage)) }
})