import type { RowDataPacket } from 'mysql2'
import { db, DB } from './db'

export interface ForumInfo {
  id: number
  category_id: number
  name: string
  description: string
  icon: string | null
  topic_count: number
  post_count: number
  last_topic_id: number | null
  last_topic_name: string | null
  last_topic_poster: string | null
}

export interface Category {
  id: number
  name: string
  forums: ForumInfo[]
}

export interface Topic {
  id: number
  name: string
  poster: string
  created: string | null
  sticky: boolean
  locked: boolean
  views: number
}

export interface Post {
  id: number
  poster: string
  text: string
  time: string | null
}

/** Índice del foro: categorías con sus foros visibles (+ contadores y último tema). */
export async function getForumIndex(): Promise<Category[]> {
  try {
    const [cats] = await db(DB.web).query<RowDataPacket[]>(
      'SELECT id, name FROM forum_categories ORDER BY `order`, id',
    )
    const [forums] = await db(DB.web).query<RowDataPacket[]>(
      `SELECT f.id, f.category_id, f.name, f.description, f.icon,
              (SELECT COUNT(*) FROM forum_topics t WHERE t.forum_id = f.id AND t.deleted = 0) AS topic_count,
              (SELECT COUNT(*) FROM forum_posts p JOIN forum_topics t ON p.topic_id = t.id
                 WHERE t.forum_id = f.id AND p.deleted = 0 AND t.deleted = 0) AS post_count,
              (SELECT t2.id FROM forum_topics t2 WHERE t2.forum_id = f.id AND t2.deleted = 0
                 ORDER BY t2.updated_at DESC, t2.id DESC LIMIT 1) AS last_topic_id,
              (SELECT t3.name FROM forum_topics t3 WHERE t3.forum_id = f.id AND t3.deleted = 0
                 ORDER BY t3.updated_at DESC, t3.id DESC LIMIT 1) AS last_topic_name,
              (SELECT t4.poster FROM forum_topics t4 WHERE t4.forum_id = f.id AND t4.deleted = 0
                 ORDER BY t4.updated_at DESC, t4.id DESC LIMIT 1) AS last_topic_poster
       FROM forums f
       WHERE f.visibility = 1 AND f.deleted = 0
       ORDER BY f.\`order\`, f.id`,
    )
    const byCat = new Map<number, ForumInfo[]>()
    for (const f of forums) {
      const info = f as unknown as ForumInfo
      if (!byCat.has(info.category_id)) byCat.set(info.category_id, [])
      byCat.get(info.category_id)!.push(info)
    }
    return cats
      .map((c) => ({ id: c.id, name: c.name, forums: byCat.get(c.id) ?? [] }))
      .filter((c) => c.forums.length > 0)
  } catch {
    return []
  }
}

export async function getForum(id: number): Promise<{ name: string; description: string } | null> {
  try {
    const [rows] = await db(DB.web).query<RowDataPacket[]>(
      'SELECT name, description FROM forums WHERE id = ? AND visibility = 1 AND deleted = 0',
      [id],
    )
    return rows[0] ? { name: rows[0].name, description: rows[0].description } : null
  } catch {
    return null
  }
}

export async function getTopics(forumId: number): Promise<Topic[]> {
  try {
    const [rows] = await db(DB.web).query<RowDataPacket[]>(
      'SELECT id, name, poster, created, sticky, locked, views FROM forum_topics WHERE forum_id = ? AND deleted = 0 ORDER BY sticky DESC, updated_at DESC, id DESC',
      [forumId],
    )
    return rows.map((r) => ({
      id: r.id,
      name: r.name,
      poster: r.poster,
      created: r.created ? new Date(r.created).toISOString() : null,
      sticky: r.sticky === 1,
      locked: r.locked === 1,
      views: r.views ?? 0,
    }))
  } catch {
    return []
  }
}

export async function getTopic(id: number): Promise<{ name: string; locked: boolean } | null> {
  try {
    const [rows] = await db(DB.web).query<RowDataPacket[]>(
      'SELECT name, locked FROM forum_topics WHERE id = ? AND deleted = 0',
      [id],
    )
    return rows[0] ? { name: rows[0].name, locked: rows[0].locked === 1 } : null
  } catch {
    return null
  }
}

export async function getPosts(topicId: number): Promise<Post[]> {
  try {
    const [rows] = await db(DB.web).query<RowDataPacket[]>(
      'SELECT id, poster, text, time FROM forum_posts WHERE topic_id = ? AND deleted = 0 ORDER BY time ASC, id ASC',
      [topicId],
    )
    return rows.map((r) => ({
      id: r.id,
      poster: r.poster,
      text: r.text,
      time: r.time ? new Date(r.time).toISOString() : null,
    }))
  } catch {
    return []
  }
}