import type { Database } from "bun:sqlite";
import type { MediaItem } from "../types";
import { getOriginalLanguage as radarrLang, type RadarrLibrary } from "./radarr";
import { getOriginalLanguage as sonarrLang, type SonarrLibrary } from "./sonarr";

export interface LanguageResolverConfig {
	radarr: { url: string; apiKey: string } | null;
	sonarr: { url: string; apiKey: string } | null;
	radarrLibrary: RadarrLibrary | null;
	sonarrLibrary: SonarrLibrary | null;
	resolveSeriesTvdb: ((seriesJellyfinId: string) => Promise<string | null>) | null;
}

export interface LanguageResult {
	origLang: string | null;
	origLangSource: string | null;
	needsReview: number;
	externalRaw: unknown;
}

/**
 * Resolve the original language of a media item using Radarr (movies) or
 * Sonarr (episodes). Pure lookup — does NOT write to the database; the
 * caller decides what to persist.
 */
export async function resolveLanguage(
	db: Database,
	itemId: number,
	cfg: LanguageResolverConfig,
): Promise<LanguageResult> {
	const item = db.prepare("SELECT * FROM media_items WHERE id = ?").get(itemId) as MediaItem | null;
	if (!item) throw new Error(`media_items row ${itemId} not found`);

	// Manual override is sacred — never touch it
	if (item.orig_lang_source === "manual") {
		return {
			origLang: item.original_language,
			origLangSource: "manual",
			needsReview: item.needs_review,
			externalRaw: null,
		};
	}

	if (item.type === "Movie") {
		return resolveMovie(item, cfg);
	}
	return resolveEpisode(item, cfg);
}

async function resolveMovie(item: MediaItem, cfg: LanguageResolverConfig): Promise<LanguageResult> {
	if (!cfg.radarr || !cfg.radarrLibrary) {
		return jellyfinFallback(item);
	}

	const lang = await radarrLang(cfg.radarr, { tmdbId: item.tmdb_id ?? undefined, imdbId: item.imdb_id ?? undefined }, cfg.radarrLibrary);
	if (lang) {
		// Capture the library entry for external_raw
		const entry =
			(item.tmdb_id ? cfg.radarrLibrary.byTmdbId.get(item.tmdb_id) : null) ??
			(item.imdb_id ? cfg.radarrLibrary.byImdbId.get(item.imdb_id) : null) ??
			null;
		return {
			origLang: lang,
			origLangSource: "radarr",
			needsReview: 0,
			externalRaw: entry,
		};
	}

	return jellyfinFallback(item);
}

async function resolveEpisode(item: MediaItem, cfg: LanguageResolverConfig): Promise<LanguageResult> {
	if (!cfg.sonarr || !cfg.sonarrLibrary) {
		return jellyfinFallback(item);
	}

	let tvdbId = item.tvdb_id;

	// If the stored tvdbId doesn't match the library, it's likely an
	// episode-level ID. Try resolving the series TVDB BEFORE hitting the
	// Sonarr API — the HTTP fallback in sonarrLang is per-item and extremely
	// slow for bulk processing.
	if (tvdbId && !cfg.sonarrLibrary.byTvdbId.has(tvdbId) && cfg.resolveSeriesTvdb && item.series_jellyfin_id) {
		const seriesTvdb = await cfg.resolveSeriesTvdb(item.series_jellyfin_id);
		if (seriesTvdb) tvdbId = seriesTvdb;
	}

	if (tvdbId) {
		const lang = await sonarrLang(cfg.sonarr, tvdbId, cfg.sonarrLibrary);
		if (lang) {
			const entry = cfg.sonarrLibrary.byTvdbId.get(tvdbId) ?? null;
			return {
				origLang: lang,
				origLangSource: "sonarr",
				needsReview: 0,
				externalRaw: entry,
			};
		}
	}

	return jellyfinFallback(item);
}

function jellyfinFallback(item: MediaItem): LanguageResult {
	return {
		origLang: item.original_language,
		origLangSource: item.orig_lang_source,
		needsReview: 1,
		externalRaw: null,
	};
}