import { unlinkSync } from "node:fs";
import { dirname, resolve as resolvePath, sep } from "node:path";
import { Hono } from "hono";
import { getAllConfig, getConfig, getDb } from "../db/index";
import { error as logError } from "../lib/log";
import { parseId } from "../lib/validate";
import { buildExtractOnlyCommand } from "../services/ffmpeg";
import { getItem, mapStream, normalizeLanguage, refreshItem } from "../services/jellyfin";
import type { MediaItem, MediaStream, ReviewPlan, StreamDecision, SubtitleFile } from "../types";

const app = new Hono();

// ─── Types ───────────────────────────────────────────────────────────────────

interface SubListItem {
	id: number;
	jellyfin_id: string;
	type: string;
	name: string;
	series_name: string | null;
	season_number: number | null;
	episode_number: number | null;
	year: number | null;
	original_language: string | null;
	file_path: string;
	subs_extracted: number | null;
	sub_count: number;
	file_count: number;
}

interface SubSeriesGroup {
	series_key: string;
	series_name: string;
	original_language: string | null;
	season_count: number;
	episode_count: number;
	not_extracted_count: number;
	extracted_count: number;
	no_subs_count: number;
}

// ─── Helpers ─────────────────────────────────────────────────────────────────

function loadDetail(db: ReturnType<typeof getDb>, itemId: number) {
	const item = db.prepare("SELECT * FROM media_items WHERE id = ?").get(itemId) as MediaItem | undefined;
	if (!item) return null;

	const subtitleStreams = db
		.prepare("SELECT * FROM media_streams WHERE item_id = ? AND type = 'Subtitle' ORDER BY stream_index")
		.all(itemId) as MediaStream[];
	const files = db
		.prepare("SELECT * FROM subtitle_files WHERE item_id = ? ORDER BY file_path")
		.all(itemId) as SubtitleFile[];
	const plan = db.prepare("SELECT * FROM review_plans WHERE item_id = ?").get(itemId) as ReviewPlan | undefined;
	const decisions = plan
		? (db
				.prepare(
					"SELECT sd.* FROM stream_decisions sd JOIN media_streams ms ON ms.id = sd.stream_id WHERE sd.plan_id = ? AND ms.type = 'Subtitle'",
				)
				.all(plan.id) as StreamDecision[])
		: [];
	const allStreams = db
		.prepare("SELECT * FROM media_streams WHERE item_id = ? ORDER BY stream_index")
		.all(itemId) as MediaStream[];
	const extractCommand = buildExtractOnlyCommand(item, allStreams);

	return {
		item,
		subtitleStreams,
		files,
		plan: plan ?? null,
		decisions,
		subs_extracted: plan?.subs_extracted ?? 0,
		extractCommand,
	};
}

// ─── List ────────────────────────────────────────────────────────────────────

function buildSubWhere(filter: string): string {
	switch (filter) {
		case "not_extracted":
			return "sub_count > 0 AND COALESCE(rp.subs_extracted, 0) = 0";
		case "extracted":
			return "rp.subs_extracted = 1";
		case "no_subs":
			return "sub_count = 0";
		default:
			return "1=1";
	}
}

app.get("/", (c) => {
	const db = getDb();
	const filter = c.req.query("filter") ?? "all";
	const where = buildSubWhere(filter);

	// Movies
	const movieRows = db
		.prepare(`
		SELECT mi.id, mi.jellyfin_id, mi.type, mi.name, mi.series_name, mi.season_number,
			mi.episode_number, mi.year, mi.original_language, mi.file_path,
			rp.subs_extracted,
			(SELECT COUNT(*) FROM media_streams ms WHERE ms.item_id = mi.id AND ms.type = 'Subtitle') as sub_count,
			(SELECT COUNT(*) FROM subtitle_files sf WHERE sf.item_id = mi.id) as file_count
		FROM media_items mi
		LEFT JOIN review_plans rp ON rp.item_id = mi.id
		WHERE mi.type = 'Movie' AND ${where}
		ORDER BY mi.name LIMIT 500
	`)
		.all() as SubListItem[];

	// Series groups
	const series = db
		.prepare(`
		SELECT COALESCE(mi.series_jellyfin_id, mi.series_name) as series_key,
			mi.series_name,
			MAX(mi.original_language) as original_language,
			COUNT(DISTINCT mi.season_number) as season_count,
			COUNT(mi.id) as episode_count,
			SUM(CASE WHEN sub_count > 0 AND COALESCE(rp.subs_extracted, 0) = 0 THEN 1 ELSE 0 END) as not_extracted_count,
			SUM(CASE WHEN rp.subs_extracted = 1 THEN 1 ELSE 0 END) as extracted_count,
			SUM(CASE WHEN sub_count = 0 THEN 1 ELSE 0 END) as no_subs_count
		FROM (
			SELECT mi.*,
				(SELECT COUNT(*) FROM media_streams ms WHERE ms.item_id = mi.id AND ms.type = 'Subtitle') as sub_count
			FROM media_items mi
			WHERE mi.type = 'Episode'
		) mi
		LEFT JOIN review_plans rp ON rp.item_id = mi.id
		WHERE ${where}
		GROUP BY series_key ORDER BY mi.series_name
	`)
		.all() as SubSeriesGroup[];

	const totalAll = (db.prepare("SELECT COUNT(*) as n FROM media_items").get() as { n: number }).n;
	const totalExtracted = (
		db.prepare("SELECT COUNT(*) as n FROM review_plans WHERE subs_extracted = 1").get() as { n: number }
	).n;
	const totalNoSubs = (
		db
			.prepare(`
		SELECT COUNT(*) as n FROM media_items mi
		WHERE NOT EXISTS (SELECT 1 FROM media_streams ms WHERE ms.item_id = mi.id AND ms.type = 'Subtitle')
	`)
			.get() as { n: number }
	).n;
	const totalNotExtracted = totalAll - totalExtracted - totalNoSubs;

	return c.json({
		movies: movieRows,
		series,
		filter,
		totalCounts: { all: totalAll, not_extracted: totalNotExtracted, extracted: totalExtracted, no_subs: totalNoSubs },
	});
});

// ─── Series episodes (subtitles) ─────────────────────────────────────────────

app.get("/series/:seriesKey/episodes", (c) => {
	const db = getDb();
	const seriesKey = decodeURIComponent(c.req.param("seriesKey"));

	const rows = db
		.prepare(`
		SELECT mi.id, mi.jellyfin_id, mi.type, mi.name, mi.series_name, mi.season_number,
			mi.episode_number, mi.year, mi.original_language, mi.file_path,
			rp.subs_extracted,
			(SELECT COUNT(*) FROM media_streams ms WHERE ms.item_id = mi.id AND ms.type = 'Subtitle') as sub_count,
			(SELECT COUNT(*) FROM subtitle_files sf WHERE sf.item_id = mi.id) as file_count
		FROM media_items mi
		LEFT JOIN review_plans rp ON rp.item_id = mi.id
		WHERE mi.type = 'Episode'
			AND (mi.series_jellyfin_id = ? OR (mi.series_jellyfin_id IS NULL AND mi.series_name = ?))
		ORDER BY mi.season_number, mi.episode_number
	`)
		.all(seriesKey, seriesKey) as SubListItem[];

	const seasonMap = new Map<number | null, SubListItem[]>();
	for (const r of rows) {
		const season = r.season_number ?? null;
		if (!seasonMap.has(season)) seasonMap.set(season, []);
		seasonMap.get(season)!.push(r);
	}

	const seasons = Array.from(seasonMap.entries())
		.sort(([a], [b]) => (a ?? -1) - (b ?? -1))
		.map(([season, episodes]) => ({
			season,
			episodes,
			extractedCount: episodes.filter((e) => e.subs_extracted === 1).length,
			notExtractedCount: episodes.filter((e) => e.sub_count > 0 && !e.subs_extracted).length,
			noSubsCount: episodes.filter((e) => e.sub_count === 0).length,
		}));

	return c.json({ seasons });
});

// ─── Summary ─────────────────────────────────────────────────────────────────

interface CategoryRow {
	language: string | null;
	is_forced: number;
	is_hearing_impaired: number;
	cnt: number;
}

function variantOf(row: { is_forced: number; is_hearing_impaired: number }): "forced" | "cc" | "standard" {
	if (row.is_forced) return "forced";
	if (row.is_hearing_impaired) return "cc";
	return "standard";
}

function catKey(lang: string | null, variant: string) {
	return `${lang ?? "__null__"}|${variant}`;
}

app.get("/summary", (c) => {
	const db = getDb();

	// Embedded count — items with subtitle streams where subs_extracted = 0
	const embeddedCount = (
		db
			.prepare(`
		SELECT COUNT(DISTINCT mi.id) as n FROM media_items mi
		JOIN media_streams ms ON ms.item_id = mi.id AND ms.type = 'Subtitle'
		LEFT JOIN review_plans rp ON rp.item_id = mi.id
		WHERE COALESCE(rp.subs_extracted, 0) = 0
	`)
			.get() as { n: number }
	).n;

	// Stream counts by (language, variant)
	const streamRows = db
		.prepare(`
		SELECT language, is_forced, is_hearing_impaired, COUNT(*) as cnt
		FROM media_streams WHERE type = 'Subtitle'
		GROUP BY language, is_forced, is_hearing_impaired
	`)
		.all() as CategoryRow[];

	// File counts by (language, variant)
	const fileRows = db
		.prepare(`
		SELECT language, is_forced, is_hearing_impaired, COUNT(*) as cnt
		FROM subtitle_files
		GROUP BY language, is_forced, is_hearing_impaired
	`)
		.all() as CategoryRow[];

	// Merge into categories
	const catMap = new Map<string, { language: string | null; variant: string; streamCount: number; fileCount: number }>();
	for (const r of streamRows) {
		const v = variantOf(r);
		const k = catKey(r.language, v);
		catMap.set(k, { language: r.language, variant: v, streamCount: r.cnt, fileCount: 0 });
	}
	for (const r of fileRows) {
		const v = variantOf(r);
		const k = catKey(r.language, v);
		const existing = catMap.get(k);
		if (existing) {
			existing.fileCount = r.cnt;
		} else {
			catMap.set(k, { language: r.language, variant: v, streamCount: 0, fileCount: r.cnt });
		}
	}
	const categories = Array.from(catMap.values()).sort((a, b) => {
		const la = a.language ?? "zzz";
		const lb = b.language ?? "zzz";
		if (la !== lb) return la.localeCompare(lb);
		return a.variant.localeCompare(b.variant);
	});

	// Title grouping
	const titleRows = db
		.prepare(`
		SELECT language, title, COUNT(*) as cnt
		FROM media_streams WHERE type = 'Subtitle'
		GROUP BY language, title
		ORDER BY language, cnt DESC
	`)
		.all() as { language: string | null; title: string | null; cnt: number }[];

	// Determine canonical title per language (most common)
	const canonicalByLang = new Map<string | null, string | null>();
	for (const r of titleRows) {
		if (!canonicalByLang.has(r.language)) canonicalByLang.set(r.language, r.title);
	}

	const titles = titleRows.map((r) => ({
		language: r.language,
		title: r.title,
		count: r.cnt,
		isCanonical: canonicalByLang.get(r.language) === r.title,
	}));

	// Keep languages from config
	const raw = getConfig("subtitle_languages");
	let keepLanguages: string[] = [];
	try {
		keepLanguages = JSON.parse(raw ?? "[]");
	} catch {
		/* empty */
	}

	return c.json({ embeddedCount, categories, titles, keepLanguages });
});

// ─── Detail ──────────────────────────────────────────────────────────────────

app.get("/:id", (c) => {
	const db = getDb();
	const id = parseId(c.req.param("id"));
	if (id == null) return c.json({ error: "invalid id" }, 400);
	const detail = loadDetail(db, id);
	if (!detail) return c.notFound();
	return c.json(detail);
});

// ─── Edit stream language ────────────────────────────────────────────────────

app.patch("/:id/stream/:streamId/language", async (c) => {
	const db = getDb();
	const itemId = parseId(c.req.param("id"));
	const streamId = parseId(c.req.param("streamId"));
	if (itemId == null || streamId == null) return c.json({ error: "invalid id" }, 400);
	const body = await c.req.json<{ language: string }>();
	const lang = (body.language ?? "").trim() || null;

	const stream = db.prepare("SELECT * FROM media_streams WHERE id = ? AND item_id = ?").get(streamId, itemId) as
		| MediaStream
		| undefined;
	if (!stream) return c.notFound();

	const normalized = lang ? normalizeLanguage(lang) : null;
	db.prepare("UPDATE media_streams SET language = ? WHERE id = ?").run(normalized, streamId);

	const detail = loadDetail(db, itemId);
	if (!detail) return c.notFound();
	return c.json(detail);
});

// ─── Edit stream title ──────────────────────────────────────────────────────

app.patch("/:id/stream/:streamId/title", async (c) => {
	const db = getDb();
	const itemId = parseId(c.req.param("id"));
	const streamId = parseId(c.req.param("streamId"));
	if (itemId == null || streamId == null) return c.json({ error: "invalid id" }, 400);
	const body = await c.req.json<{ title: string }>();
	const title = (body.title ?? "").trim() || null;

	const plan = db.prepare("SELECT id FROM review_plans WHERE item_id = ?").get(itemId) as { id: number } | undefined;
	if (!plan) return c.notFound();
	db
		.prepare("UPDATE stream_decisions SET custom_title = ? WHERE plan_id = ? AND stream_id = ?")
		.run(title, plan.id, streamId);

	const detail = loadDetail(db, itemId);
	if (!detail) return c.notFound();
	return c.json(detail);
});

// ─── Extract all ──────────────────────────────────────────────────────────────

app.post("/extract-all", (c) => {
	const db = getDb();
	// Find items with subtitle streams that haven't been extracted yet
	const items = db
		.prepare(`
		SELECT mi.* FROM media_items mi
		WHERE EXISTS (SELECT 1 FROM media_streams ms WHERE ms.item_id = mi.id AND ms.type = 'Subtitle')
		AND NOT EXISTS (SELECT 1 FROM review_plans rp WHERE rp.item_id = mi.id AND rp.subs_extracted = 1)
		AND NOT EXISTS (SELECT 1 FROM jobs j WHERE j.item_id = mi.id AND j.status IN ('pending', 'running'))
	`)
		.all() as MediaItem[];

	let queued = 0;
	for (const item of items) {
		const streams = db
			.prepare("SELECT * FROM media_streams WHERE item_id = ? ORDER BY stream_index")
			.all(item.id) as MediaStream[];
		const command = buildExtractOnlyCommand(item, streams);
		if (!command) continue;
		db
			.prepare("INSERT INTO jobs (item_id, command, job_type, status) VALUES (?, ?, 'subtitle', 'pending')")
			.run(item.id, command);
		queued++;
	}

	return c.json({ ok: true, queued });
});

// ─── Extract ─────────────────────────────────────────────────────────────────

app.post("/:id/extract", (c) => {
	const db = getDb();
	const id = parseId(c.req.param("id"));
	if (id == null) return c.json({ error: "invalid id" }, 400);

	const item = db.prepare("SELECT * FROM media_items WHERE id = ?").get(id) as MediaItem | undefined;
	if (!item) return c.notFound();

	const plan = db.prepare("SELECT * FROM review_plans WHERE item_id = ?").get(id) as ReviewPlan | undefined;
	if (plan?.subs_extracted) return c.json({ ok: false, error: "Subtitles already extracted" }, 409);

	const streams = db
		.prepare("SELECT * FROM media_streams WHERE item_id = ? ORDER BY stream_index")
		.all(id) as MediaStream[];
	const command = buildExtractOnlyCommand(item, streams);
	if (!command) return c.json({ ok: false, error: "No subtitles to extract" }, 400);

	db
		.prepare("INSERT INTO jobs (item_id, command, job_type, status) VALUES (?, ?, 'subtitle', 'pending')")
		.run(id, command);
	return c.json({ ok: true });
});

// ─── Delete file ─────────────────────────────────────────────────────────────

/**
 * Verify a sidecar file path lives inside the directory of its owning
 * media item. Guards against path-traversal via malformed DB state.
 */
function isSidecarOfItem(filePath: string, videoPath: string): boolean {
	const videoDir = resolvePath(dirname(videoPath));
	const targetDir = resolvePath(dirname(filePath));
	return targetDir === videoDir || targetDir.startsWith(videoDir + sep);
}

app.delete("/:id/files/:fileId", (c) => {
	const db = getDb();
	const itemId = parseId(c.req.param("id"));
	const fileId = parseId(c.req.param("fileId"));
	if (itemId == null || fileId == null) return c.json({ error: "invalid id" }, 400);

	const file = db.prepare("SELECT * FROM subtitle_files WHERE id = ? AND item_id = ?").get(fileId, itemId) as
		| SubtitleFile
		| undefined;
	if (!file) return c.notFound();

	const item = db.prepare("SELECT file_path FROM media_items WHERE id = ?").get(itemId) as
		| { file_path: string }
		| undefined;
	if (!item || !isSidecarOfItem(file.file_path, item.file_path)) {
		logError(`Refusing to delete subtitle file outside media dir: ${file.file_path}`);
		db.prepare("DELETE FROM subtitle_files WHERE id = ?").run(fileId);
		return c.json({ ok: false, error: "file path outside media directory; DB entry removed without touching disk" }, 400);
	}

	try {
		unlinkSync(file.file_path);
	} catch {
		/* file may not exist */
	}
	db.prepare("DELETE FROM subtitle_files WHERE id = ?").run(fileId);

	const files = db
		.prepare("SELECT * FROM subtitle_files WHERE item_id = ? ORDER BY file_path")
		.all(itemId) as SubtitleFile[];
	return c.json({ ok: true, files });
});

// ─── Rescan ──────────────────────────────────────────────────────────────────

app.post("/:id/rescan", async (c) => {
	const db = getDb();
	const id = parseId(c.req.param("id"));
	if (id == null) return c.json({ error: "invalid id" }, 400);
	const item = db.prepare("SELECT * FROM media_items WHERE id = ?").get(id) as MediaItem | undefined;
	if (!item) return c.notFound();

	const cfg = getAllConfig();
	const jfCfg = { url: cfg.jellyfin_url, apiKey: cfg.jellyfin_api_key, userId: cfg.jellyfin_user_id };

	await refreshItem(jfCfg, item.jellyfin_id);

	const fresh = await getItem(jfCfg, item.jellyfin_id);
	if (fresh) {
		const insertStream = db.prepare(`
			INSERT INTO media_streams (item_id, stream_index, type, codec, language, language_display,
				title, is_default, is_forced, is_hearing_impaired, channels, channel_layout, bit_rate, sample_rate)
			VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
		`);
		db.prepare("DELETE FROM media_streams WHERE item_id = ?").run(id);
		for (const jStream of fresh.MediaStreams ?? []) {
			if (jStream.IsExternal) continue;
			const s = mapStream(jStream);
			insertStream.run(
				id,
				s.stream_index,
				s.type,
				s.codec,
				s.language,
				s.language_display,
				s.title,
				s.is_default,
				s.is_forced,
				s.is_hearing_impaired,
				s.channels,
				s.channel_layout,
				s.bit_rate,
				s.sample_rate,
			);
		}
	}

	const detail = loadDetail(db, id);
	if (!detail) return c.notFound();
	return c.json(detail);
});

// ─── Batch delete subtitle files ─────────────────────────────────────────────

app.post("/batch-delete", async (c) => {
	const db = getDb();
	const body = await c.req.json<{ categories: { language: string | null; variant: "standard" | "forced" | "cc" }[] }>();

	let deleted = 0;
	for (const cat of body.categories) {
		const isForced = cat.variant === "forced" ? 1 : 0;
		const isHI = cat.variant === "cc" ? 1 : 0;

		let files: SubtitleFile[];
		if (cat.language === null) {
			files = db
				.prepare(`
				SELECT * FROM subtitle_files
				WHERE language IS NULL AND is_forced = ? AND is_hearing_impaired = ?
			`)
				.all(isForced, isHI) as SubtitleFile[];
		} else {
			files = db
				.prepare(`
				SELECT * FROM subtitle_files
				WHERE language = ? AND is_forced = ? AND is_hearing_impaired = ?
			`)
				.all(cat.language, isForced, isHI) as SubtitleFile[];
		}

		for (const file of files) {
			const item = db.prepare("SELECT file_path FROM media_items WHERE id = ?").get(file.item_id) as
				| { file_path: string }
				| undefined;
			if (item && isSidecarOfItem(file.file_path, item.file_path)) {
				try {
					unlinkSync(file.file_path);
				} catch {
					/* file may not exist */
				}
			} else {
				logError(`Refusing to delete subtitle file outside media dir: ${file.file_path}`);
			}
			db.prepare("DELETE FROM subtitle_files WHERE id = ?").run(file.id);
			deleted++;
		}

		// Reset subs_extracted for affected items that now have no subtitle files
		const affectedItems = new Set(files.map((f) => f.item_id));
		for (const itemId of affectedItems) {
			const remaining = (
				db.prepare("SELECT COUNT(*) as n FROM subtitle_files WHERE item_id = ?").get(itemId) as { n: number }
			).n;
			if (remaining === 0) {
				db.prepare("UPDATE review_plans SET subs_extracted = 0 WHERE item_id = ?").run(itemId);
			}
		}
	}

	return c.json({ ok: true, deleted });
});

// ─── Normalize titles ────────────────────────────────────────────────────────

app.post("/normalize-titles", (c) => {
	const db = getDb();

	// Get title groups per language
	const titleRows = db
		.prepare(`
		SELECT language, title, COUNT(*) as cnt
		FROM media_streams WHERE type = 'Subtitle'
		GROUP BY language, title
		ORDER BY language, cnt DESC
	`)
		.all() as { language: string | null; title: string | null; cnt: number }[];

	// Find canonical (most common) title per language
	const canonicalByLang = new Map<string | null, string | null>();
	for (const r of titleRows) {
		if (!canonicalByLang.has(r.language)) canonicalByLang.set(r.language, r.title);
	}

	let normalized = 0;
	for (const r of titleRows) {
		const canonical = canonicalByLang.get(r.language);
		if (r.title === canonical) continue;

		// Find all streams matching this language+title and set custom_title on their decisions
		let streams: { id: number; item_id: number }[];
		if (r.language === null) {
			streams = db
				.prepare(`
				SELECT id, item_id FROM media_streams
				WHERE type = 'Subtitle' AND language IS NULL AND title IS ?
			`)
				.all(r.title) as { id: number; item_id: number }[];
		} else {
			streams = db
				.prepare(`
				SELECT id, item_id FROM media_streams
				WHERE type = 'Subtitle' AND language = ? AND title IS ?
			`)
				.all(r.language, r.title) as { id: number; item_id: number }[];
		}

		for (const stream of streams) {
			// Ensure review_plan exists
			let plan = db.prepare("SELECT id FROM review_plans WHERE item_id = ?").get(stream.item_id) as
				| { id: number }
				| undefined;
			if (!plan) {
				db.prepare("INSERT INTO review_plans (item_id, status, is_noop) VALUES (?, 'pending', 0)").run(stream.item_id);
				plan = db.prepare("SELECT id FROM review_plans WHERE item_id = ?").get(stream.item_id) as { id: number };
			}

			// Upsert stream_decision with custom_title
			const existing = db
				.prepare("SELECT id FROM stream_decisions WHERE plan_id = ? AND stream_id = ?")
				.get(plan.id, stream.id);
			if (existing) {
				db
					.prepare("UPDATE stream_decisions SET custom_title = ? WHERE plan_id = ? AND stream_id = ?")
					.run(canonical, plan.id, stream.id);
			} else {
				db
					.prepare("INSERT INTO stream_decisions (plan_id, stream_id, action, custom_title) VALUES (?, ?, 'keep', ?)")
					.run(plan.id, stream.id, canonical);
			}
			normalized++;
		}
	}

	return c.json({ ok: true, normalized });
});

export default app;