fix(tvdb): respect display language when fetching metadata (#1889)

* fix(tvdb): respect display language when fetching metadata

* refactor(tvdb): use seasons translation

* refactor(tvdb): limit while loop

* fix(tvdb): fix translation with '-'

* refactor(tvdb): remove logs

* style(tvdb): remove useless logs

* refactor(tvdb): simplify wanted translation condition

* refactor(languages): move AvailableLocale  from context to types

server/api/tvdb/index.ts

@@ -7,12 +7,13 @@ import type {
   TmdbTvEpisodeResult,
   TmdbTvSeasonResult,
 } from '@server/api/themoviedb/interfaces';
-import type {
-  TvdbBaseResponse,
-  TvdbEpisode,
-  TvdbLoginResponse,
-  TvdbSeasonDetails,
-  TvdbTvDetails,
+import {
+  convertTmdbLanguageToTvdbWithFallback,
+  type TvdbBaseResponse,
+  type TvdbEpisode,
+  type TvdbLoginResponse,
+  type TvdbSeasonDetails,
+  type TvdbTvDetails,
 } from '@server/api/tvdb/interfaces';
 import cacheManager, { type AvailableCacheIds } from '@server/lib/cache';
 import logger from '@server/logger';
@@ -215,7 +216,12 @@ class Tvdb extends ExternalAPI implements TvShowProvider {
           return await this.tmdb.getTvSeason({ tvId, seasonNumber, language });
         }
 
-        return await this.getTvdbSeasonData(tvdbId, seasonNumber, tvId);
+        return await this.getTvdbSeasonData(
+          tvdbId,
+          seasonNumber,
+          tvId,
+          language
+        );
       } catch (error) {
         this.handleError('Failed to fetch TV season details', error);
         return await this.tmdb.getTvSeason({ tvId, seasonNumber, language });
@@ -316,8 +322,8 @@ class Tvdb extends ExternalAPI implements TvShowProvider {
   private async getTvdbSeasonData(
     tvdbId: number,
     seasonNumber: number,
-    tvId: number
-    //language: string = Tvdb.DEFAULT_LANGUAGE
+    tvId: number,
+    language: string = Tvdb.DEFAULT_LANGUAGE
   ): Promise<TmdbSeasonWithEpisodes> {
     const tvdbData = await this.fetchTvdbShowData(tvdbId);
 
@@ -341,6 +347,132 @@ class Tvdb extends ExternalAPI implements TvShowProvider {
       return this.createEmptySeasonResponse(tvId);
     }
 
+    const wantedTranslation = convertTmdbLanguageToTvdbWithFallback(
+      language,
+      Tvdb.DEFAULT_LANGUAGE
+    );
+
+    // check if translation is available for the season
+    const availableTranslation = season.nameTranslations.filter(
+      (translation) =>
+        translation === wantedTranslation ||
+        translation === Tvdb.DEFAULT_LANGUAGE
+    );
+
+    if (!availableTranslation) {
+      return this.getSeasonWithOriginalLanguage(
+        tvdbId,
+        tvId,
+        seasonNumber,
+        season
+      );
+    }
+
+    return this.getSeasonWithTranslation(
+      tvdbId,
+      tvId,
+      seasonNumber,
+      season,
+      wantedTranslation
+    );
+  }
+
+  private async getSeasonWithTranslation(
+    tvdbId: number,
+    tvId: number,
+    seasonNumber: number,
+    season: TvdbSeasonDetails,
+    language: string
+  ): Promise<TmdbSeasonWithEpisodes> {
+    if (!season) {
+      logger.error(
+        `Failed to find season ${seasonNumber} for TVDB ID: ${tvdbId}`
+      );
+      return this.createEmptySeasonResponse(tvId);
+    }
+
+    const allEpisodes = [] as TvdbEpisode[];
+    let page = 0;
+    // Limit to max 50 pages to avoid infinite loops.
+    // 50 pages with 500 items per page = 25_000 episodes in a series which should be more than enough
+    const maxPages = 50;
+
+    while (page < maxPages) {
+      const resp = await this.get<TvdbBaseResponse<TvdbSeasonDetails>>(
+        `/series/${tvdbId}/episodes/default/${language}`,
+        {
+          headers: {
+            Authorization: `Bearer ${this.token}`,
+          },
+          params: {
+            page: page,
+          },
+        }
+      );
+
+      if (!resp?.data?.episodes) {
+        logger.warn(
+          `No episodes found for TVDB ID: ${tvdbId} on page ${page} for season ${seasonNumber}`
+        );
+        break;
+      }
+
+      const { episodes } = resp.data;
+
+      if (!episodes) {
+        logger.debug(
+          `No more episodes found for TVDB ID: ${tvdbId} on page ${page} for season ${seasonNumber}`
+        );
+        break;
+      }
+
+      allEpisodes.push(...episodes);
+
+      const hasNextPage = resp.links?.next && episodes.length > 0;
+
+      if (!hasNextPage) {
+        break;
+      }
+
+      page++;
+    }
+
+    if (page >= maxPages) {
+      logger.warn(
+        `Reached max pages (${maxPages}) for TVDB ID: ${tvdbId} on season ${seasonNumber} with language ${language}. There might be more episodes available.`
+      );
+    }
+
+    const episodes = this.processEpisodes(
+      { ...season, episodes: allEpisodes },
+      seasonNumber,
+      tvId
+    );
+
+    return {
+      episodes,
+      external_ids: { tvdb_id: tvdbId },
+      name: '',
+      overview: '',
+      id: season.id,
+      air_date: season.firstAired,
+      season_number: episodes.length,
+    };
+  }
+
+  private async getSeasonWithOriginalLanguage(
+    tvdbId: number,
+    tvId: number,
+    seasonNumber: number,
+    season: TvdbSeasonDetails
+  ): Promise<TmdbSeasonWithEpisodes> {
+    if (!season) {
+      logger.error(
+        `Failed to find season ${seasonNumber} for TVDB ID: ${tvdbId}`
+      );
+      return this.createEmptySeasonResponse(tvId);
+    }
+
     const resp = await this.get<TvdbBaseResponse<TvdbSeasonDetails>>(
       `/seasons/${season.id}/extended`,
       {
@@ -394,7 +526,10 @@ class Tvdb extends ExternalAPI implements TvShowProvider {
       season_number: episode.seasonNumber,
       production_code: '',
       show_id: tvId,
-      still_path: episode.image ? episode.image : '',
+      still_path:
+        episode.image && !episode.image.startsWith('https://')
+          ? 'https://artworks.thetvdb.com' + episode.image
+          : '',
       vote_average: 1,
       vote_count: 1,
     };

server/api/tvdb/interfaces.ts

@@ -1,6 +1,17 @@
+import { type AvailableLocale } from '@server/types/languages';
+
 export interface TvdbBaseResponse<T> {
   data: T;
   errors: string;
+  links?: TvdbPagination;
+}
+
+export interface TvdbPagination {
+  prev?: string;
+  self: string;
+  next?: string;
+  totalItems: number;
+  pageSize: number;
 }
 
 export interface TvdbLoginResponse {
@@ -142,3 +153,64 @@ export interface TvdbEpisodeTranslation {
   overview: string;
   language: string;
 }
+
+const TMDB_TO_TVDB_MAPPING: Record<string, string> & {
+  [key in AvailableLocale]: string;
+} = {
+  ar: 'ara', // Arabic
+  bg: 'bul', // Bulgarian
+  ca: 'cat', // Catalan
+  cs: 'ces', // Czech
+  da: 'dan', // Danish
+  de: 'deu', // German
+  el: 'ell', // Greek
+  en: 'eng', // English
+  es: 'spa', // Spanish
+  fi: 'fin', // Finnish
+  fr: 'fra', // French
+  he: 'heb', // Hebrew
+  hi: 'hin', // Hindi
+  hr: 'hrv', // Croatian
+  hu: 'hun', // Hungarian
+  it: 'ita', // Italian
+  ja: 'jpn', // Japanese
+  ko: 'kor', // Korean
+  lt: 'lit', // Lithuanian
+  nl: 'nld', // Dutch
+  pl: 'pol', // Polish
+  ro: 'ron', // Romanian
+  ru: 'rus', // Russian
+  sq: 'sqi', // Albanian
+  sr: 'srp', // Serbian
+  sv: 'swe', // Swedish
+  tr: 'tur', // Turkish
+  uk: 'ukr', // Ukrainian
+
+  'es-MX': 'spa', // Spanish (Latin America) -> Spanish
+  'nb-NO': 'nor', // Norwegian Bokmål -> Norwegian
+  'pt-BR': 'pt', // Portuguese (Brazil) -> Portuguese - Brazil (from TVDB data)
+  'pt-PT': 'por', // Portuguese (Portugal) -> Portuguese - Portugal (from TVDB data)
+  'zh-CN': 'zho', // Chinese (Simplified) -> Chinese - China
+  'zh-TW': 'zhtw', // Chinese (Traditional) -> Chinese - Taiwan
+};
+
+export function convertTMDBToTVDB(tmdbCode: string): string | null {
+  const normalizedCode = tmdbCode.toLowerCase();
+
+  return (
+    TMDB_TO_TVDB_MAPPING[tmdbCode] ||
+    TMDB_TO_TVDB_MAPPING[normalizedCode] ||
+    null
+  );
+}
+
+export function convertTmdbLanguageToTvdbWithFallback(
+  tmdbCode: string,
+  fallback: string
+): string {
+  // First try exact match
+  const tvdbCode = convertTMDBToTVDB(tmdbCode);
+  if (tvdbCode) return tvdbCode;
+
+  return tvdbCode || fallback || 'eng'; // Default to English if no match found
+}