import type { DB } from './db.js'
import { isConfidentMatch, normalize } from './matcher.js'

export type RipStatus = 'ripped' | 'not_ripped'

/**
 * Resolution order per spec:
 * 1. manual rip_override (non-null) wins
 * 2. else a stored match_link means ripped
 * 3. else confident fuzzy match against the user's digital_albums
 */
export function resolveRipStatus(db: DB, userId: number, itemId: number): RipStatus {
  const item = db
    .prepare('SELECT id, title, artist, rip_override FROM collection_items WHERE id = ? AND user_id = ?')
    .get(itemId, userId) as
    | { id: number; title: string; artist: string; rip_override: number | null }
    | undefined
  if (!item) return 'not_ripped'

  if (item.rip_override !== null && item.rip_override !== undefined) {
    return item.rip_override === 1 ? 'ripped' : 'not_ripped'
  }

  const link = db.prepare('SELECT album_id FROM match_links WHERE item_id = ?').get(itemId)
  if (link) return 'ripped'

  const albums = db
    .prepare('SELECT title, artist FROM digital_albums WHERE user_id = ?')
    .all(userId) as { title: string; artist: string }[]
  return albums.some((a) => isConfidentMatch(item, a)) ? 'ripped' : 'not_ripped'
}

/**
 * Batch resolution for list views: loads albums and match links once per
 * user instead of per item (GET /api/collection is otherwise O(items x albums)).
 * Resolution order matches resolveRipStatus.
 */
export function resolveRipStatusBatch(
  db: DB,
  userId: number,
  items: { id: number; title: string; artist: string; rip_override: number | null }[]
): RipStatus[] {
  const albums = db
    .prepare('SELECT title, artist FROM digital_albums WHERE user_id = ?')
    .all(userId) as { title: string; artist: string }[]
  const albumKeys = new Set(
    albums.map((a) => `${normalize(a.title)}|${normalize(a.artist)}`)
  )
  const linked = new Set(
    (
      db.prepare('SELECT item_id FROM match_links WHERE user_id = ?').all(userId) as {
        item_id: number
      }[]
    ).map((r) => r.item_id)
  )
  return items.map((item) => {
    if (item.rip_override !== null && item.rip_override !== undefined) {
      return item.rip_override === 1 ? 'ripped' : 'not_ripped'
    }
    if (linked.has(item.id)) return 'ripped'
    const key = `${normalize(item.title)}|${normalize(item.artist)}`
    return albumKeys.has(key) ? 'ripped' : 'not_ripped'
  })
}

export interface MatchedAlbum {
  id: number
  subsonicId: string
  lastPlayedAt: string | null
}

/** Album behind an item's rip match — link wins, else confident fuzzy match. Independent of rip_override. */
export function findMatchedAlbum(db: DB, userId: number, itemId: number): MatchedAlbum | null {
  const item = db
    .prepare('SELECT id, title, artist FROM collection_items WHERE id = ? AND user_id = ?')
    .get(itemId, userId) as { id: number; title: string; artist: string } | undefined
  if (!item) return null

  const link = db
    .prepare(
      `SELECT da.id, da.subsonic_id, da.last_played_at FROM match_links ml
       JOIN digital_albums da ON da.id = ml.album_id WHERE ml.item_id = ?`
    )
    .get(itemId) as { id: number; subsonic_id: string; last_played_at: string | null } | undefined
  if (link) {
    return { id: link.id, subsonicId: link.subsonic_id, lastPlayedAt: link.last_played_at }
  }

  const album = db
    .prepare(
      `SELECT id, subsonic_id, last_played_at, title, artist FROM digital_albums WHERE user_id = ?`
    )
    .all(userId) as { id: number; subsonic_id: string; last_played_at: string | null; title: string; artist: string }[]
  const match = album.find((a) => isConfidentMatch(item, a))
  return match
    ? { id: match.id, subsonicId: match.subsonic_id, lastPlayedAt: match.last_played_at }
    : null
}