import { ref } from 'vue'
import type { MediaDataSource, MediaSourceInfo } from '@/api/types'

const MUSICBRAINZ_ID_PATTERN = /^[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}$/i
const IMDB_ID_PATTERN = /^tt\d+$/i
export const MUSIC_MEDIA_SOURCES = ['musicbrainz', 'theaudiodb', 'doubanmusic'] as const
const MEDIA_SOURCE_PATTERN = /^[a-z][a-z0-9._-]{0,63}$/
const mediaSourceCatalog = ref<MediaSourceInfo[]>([])

const MUSIC_MEDIA_TYPES = new Set(['音乐', 'music'])
const VIDEO_MEDIA_TYPES = new Set(['电影', '电视剧', 'movie', 'tv'])

/** 更新宿主与插件合并后的来源目录，并保留合法来源的稳定顺序。 */
export function setMediaSourceCatalog(sources: MediaSourceInfo[]) {
  const seen = new Set<string>()
  mediaSourceCatalog.value = sources.reduce<MediaSourceInfo[]>((catalog, source) => {
    const value = source?.media_source?.toString().trim().toLowerCase()
    if (!value || !MEDIA_SOURCE_PATTERN.test(value) || seen.has(value)) return catalog
    seen.add(value)
    catalog.push({ ...source, media_source: value })
    return catalog
  }, [])
}

/** 返回当前已加载的来源目录，供来源选择器构造选项。 */
export function getMediaSourceCatalog() {
  return mediaSourceCatalog
}

/** 判断注册来源是否声明了指定的影视或音乐能力。 */
export function supportsMediaSourceType(
  source: Pick<MediaSourceInfo, 'media_types'>,
  kind: 'media' | 'music',
): boolean {
  const mediaTypes = (source.media_types ?? [])
    .filter(type => typeof type === 'string')
    .map(type => type.trim().toLowerCase())
  const supportedTypes = kind === 'music' ? MUSIC_MEDIA_TYPES : VIDEO_MEDIA_TYPES
  return mediaTypes.some(type => supportedTypes.has(type))
}

/** 判断外部输入是否为内置或插件注册的规范媒体来源标识。 */
export function isMediaDataSource(value: unknown): value is MediaDataSource {
  return typeof value === 'string' && MEDIA_SOURCE_PATTERN.test(value)
}

/** 将路由或表单中的单值、逗号分隔值及数组统一解析为去重后的规范来源。 */
export function parseMediaDataSources(value: unknown): MediaDataSource[] {
  const values = Array.isArray(value) ? value : [value]
  return [
    ...new Set(
      values
        .flatMap(item => (typeof item === 'string' ? item.split(',') : []))
        .map(item => item.trim().toLowerCase())
        .filter(isMediaDataSource),
    ),
  ]
}

/** 判断当前请求来源是否为内置或插件注册的音乐元数据源。 */
export function isMusicMediaSource(source?: MediaDataSource): boolean {
  const normalized = source?.toString().trim().toLowerCase()
  if (!normalized) return false
  return (
    MUSIC_MEDIA_SOURCES.includes(normalized as (typeof MUSIC_MEDIA_SOURCES)[number]) ||
    mediaSourceCatalog.value.some(item => item.media_source === normalized && supportsMediaSourceType(item, 'music'))
  )
}

/** 按媒体数据源校验有固定格式的原生 ID，其余来源只要求非空。 */
export function isValidMediaSourceId(value: string | number | null | undefined, source?: MediaDataSource): boolean {
  const normalized = value?.toString().trim()
  if (!normalized) return true
  if (normalized === '0') return false
  if (source === 'musicbrainz') return MUSICBRAINZ_ID_PATTERN.test(normalized)
  if (source === 'doubanmusic' && normalized.includes(':')) {
    return /^\d+:\d+$/.test(normalized)
  }
  if (source === 'imdb') return IMDB_ID_PATTERN.test(normalized)
  return true
}