netfelix-audio-fix/server/services/__tests__/ffmpeg.test.ts

import { describe, expect, test } from "bun:test";
import type { MediaItem, MediaStream, StreamDecision } from "../../types";
import { buildCommand, buildPipelineCommand, predictExtractedFiles, shellQuote, sortKeptStreams } from "../ffmpeg";

function stream(o: Partial<MediaStream> & Pick<MediaStream, "id" | "type" | "stream_index">): MediaStream {
	return {
		item_id: 1,
		codec: null,
		profile: null,
		language: null,
		language_display: null,
		title: null,
		is_default: 0,
		is_forced: 0,
		is_hearing_impaired: 0,
		channels: null,
		channel_layout: null,
		bit_rate: null,
		sample_rate: null,
		bit_depth: null,
		...o,
	};
}

function decision(o: Partial<StreamDecision> & Pick<StreamDecision, "stream_id" | "action">): StreamDecision {
	return {
		id: 0,
		plan_id: 1,
		target_index: null,
		custom_title: null,
		transcode_codec: null,
		...o,
	};
}

const ITEM: MediaItem = {
	id: 1,
	jellyfin_id: "x",
	type: "Movie",
	name: "Test",
	original_title: null,
	series_name: null,
	series_jellyfin_id: null,
	season_number: null,
	episode_number: null,
	year: null,
	file_path: "/movies/Test.mkv",
	file_size: null,
	container: "mkv",
	runtime_ticks: null,
	date_last_refreshed: null,
	original_language: "eng",
	orig_lang_source: "jellyfin",
	needs_review: 0,
	imdb_id: null,
	tmdb_id: null,
	tvdb_id: null,
	jellyfin_raw: null,
	external_raw: null,
	scan_status: "scanned",
	scan_error: null,
	last_scanned_at: null,
	last_executed_at: null,
	created_at: "",
};

describe("shellQuote", () => {
	test("wraps plain strings in single quotes", () => {
		expect(shellQuote("hello")).toBe("'hello'");
	});

	test("escapes single quotes safely", () => {
		expect(shellQuote("it's")).toBe("'it'\\''s'");
	});

	test("handles paths with spaces", () => {
		expect(shellQuote("/movies/My Movie.mkv")).toBe("'/movies/My Movie.mkv'");
	});
});

describe("sortKeptStreams", () => {
	test("orders by type priority (Video, Audio, Subtitle, Data), then target_index", () => {
		const streams = [
			stream({ id: 1, type: "Audio", stream_index: 1 }),
			stream({ id: 2, type: "Video", stream_index: 0 }),
			stream({ id: 3, type: "Audio", stream_index: 2 }),
		];
		const decisions = [
			decision({ stream_id: 1, action: "keep", target_index: 1 }),
			decision({ stream_id: 2, action: "keep", target_index: 0 }),
			decision({ stream_id: 3, action: "keep", target_index: 0 }),
		];
		const sorted = sortKeptStreams(streams, decisions);
		expect(sorted.map((k) => k.stream.id)).toEqual([2, 3, 1]);
	});

	test("drops streams with action remove", () => {
		const streams = [stream({ id: 1, type: "Audio", stream_index: 0 })];
		const decisions = [decision({ stream_id: 1, action: "remove" })];
		expect(sortKeptStreams(streams, decisions)).toEqual([]);
	});
});

describe("buildCommand", () => {
	test("produces ffmpeg remux with tmp-rename pattern", () => {
		const streams = [
			stream({ id: 1, type: "Video", stream_index: 0, codec: "h264" }),
			stream({ id: 2, type: "Audio", stream_index: 1, codec: "aac", language: "eng" }),
		];
		const decisions = [
			decision({ stream_id: 1, action: "keep", target_index: 0 }),
			decision({ stream_id: 2, action: "keep", target_index: 0 }),
		];
		const cmd = buildCommand(ITEM, streams, decisions);
		expect(cmd).toContain("ffmpeg");
		expect(cmd).toContain("-map 0:v:0");
		expect(cmd).toContain("-map 0:a:0");
		expect(cmd).toContain("-c copy");
		expect(cmd).toContain("'/movies/Test.tmp.mkv'");
		expect(cmd).toContain("mv '/movies/Test.tmp.mkv' '/movies/Test.mkv'");
	});

	test("uses type-relative specifiers (0:a:N) not absolute stream_index", () => {
		const streams = [
			stream({ id: 1, type: "Video", stream_index: 0 }),
			stream({ id: 2, type: "Audio", stream_index: 1 }),
			stream({ id: 3, type: "Audio", stream_index: 2 }),
		];
		// Keep only the second audio; still mapped as 0:a:1
		const decisions = [
			decision({ stream_id: 1, action: "keep", target_index: 0 }),
			decision({ stream_id: 2, action: "remove" }),
			decision({ stream_id: 3, action: "keep", target_index: 0 }),
		];
		const cmd = buildCommand(ITEM, streams, decisions);
		expect(cmd).toContain("-map 0:a:1");
		expect(cmd).not.toContain("-map 0:a:2");
	});

	test("extracts every subtitle to a sidecar even when audio decisions are the main reason to process", () => {
		// Regression: buildCommand used to strip subtitles from the container
		// without extracting them first — a 37-subtitle file would have lost
		// all 37. It now delegates to buildPipelineCommand, so every subtitle
		// gets a -map 0:s:N extraction output.
		const streams = [
			stream({ id: 1, type: "Video", stream_index: 0, codec: "h264" }),
			stream({ id: 2, type: "Audio", stream_index: 1, codec: "aac", language: "eng" }),
			stream({ id: 3, type: "Audio", stream_index: 2, codec: "aac", language: "fra" }),
			stream({ id: 4, type: "Subtitle", stream_index: 3, codec: "subrip", language: "eng" }),
			stream({ id: 5, type: "Subtitle", stream_index: 4, codec: "subrip", language: "deu" }),
		];
		const decisions = [
			decision({ stream_id: 1, action: "keep", target_index: 0 }),
			decision({ stream_id: 2, action: "keep", target_index: 0 }),
			decision({ stream_id: 3, action: "remove" }),
			decision({ stream_id: 4, action: "remove" }),
			decision({ stream_id: 5, action: "remove" }),
		];
		const cmd = buildCommand(ITEM, streams, decisions);
		expect(cmd).toContain("-map 0:s:0");
		expect(cmd).toContain("-map 0:s:1");
		expect(cmd).toContain("'/movies/Test.en.srt'");
		expect(cmd).toContain("'/movies/Test.de.srt'");
	});

	test("writes canonical iso3 language metadata on every kept audio stream", () => {
		const streams = [
			stream({ id: 1, type: "Video", stream_index: 0 }),
			stream({ id: 2, type: "Audio", stream_index: 1, language: "en" }), // 2-letter → eng
			stream({ id: 3, type: "Audio", stream_index: 2, language: "ger" }), // alias → deu
			stream({ id: 4, type: "Audio", stream_index: 3, language: null }), // unknown → und
		];
		const decisions = [
			decision({ stream_id: 1, action: "keep", target_index: 0 }),
			decision({ stream_id: 2, action: "keep", target_index: 0 }),
			decision({ stream_id: 3, action: "keep", target_index: 1 }),
			decision({ stream_id: 4, action: "keep", target_index: 2 }),
		];
		const cmd = buildCommand(ITEM, streams, decisions);
		expect(cmd).toContain("-metadata:s:a:0 language=eng");
		expect(cmd).toContain("-metadata:s:a:1 language=deu");
		expect(cmd).toContain("-metadata:s:a:2 language=und");
	});

	test("writes canonical 'ENG - CODEC · CHANNELS' title on every kept audio stream", () => {
		const streams = [
			stream({ id: 1, type: "Video", stream_index: 0 }),
			stream({
				id: 2,
				type: "Audio",
				stream_index: 1,
				codec: "ac3",
				channels: 6,
				language: "eng",
				title: "Audio Description",
			}),
			stream({ id: 3, type: "Audio", stream_index: 2, codec: "dts", channels: 1, language: "deu" }),
			stream({ id: 4, type: "Audio", stream_index: 3, codec: "aac", channels: 2, language: null }),
		];
		const decisions = [
			decision({ stream_id: 1, action: "keep", target_index: 0 }),
			decision({ stream_id: 2, action: "keep", target_index: 0 }),
			decision({ stream_id: 3, action: "keep", target_index: 1 }),
			decision({ stream_id: 4, action: "keep", target_index: 2 }),
		];
		const cmd = buildCommand(ITEM, streams, decisions);
		// Original "Audio Description" title is replaced with the harmonized form.
		expect(cmd).toContain("-metadata:s:a:0 title='ENG - AC3 · 5.1'");
		// Mono renders as 1.0 (not the legacy "mono" string).
		expect(cmd).toContain("-metadata:s:a:1 title='DEU - DTS · 1.0'");
		// Stereo renders as 2.0.
		expect(cmd).toContain("-metadata:s:a:2 title='AAC · 2.0'");
	});

	test("custom_title still overrides the auto-generated audio title", () => {
		const streams = [
			stream({ id: 1, type: "Video", stream_index: 0 }),
			stream({ id: 2, type: "Audio", stream_index: 1, codec: "ac3", channels: 6, language: "eng" }),
		];
		const decisions = [
			decision({ stream_id: 1, action: "keep", target_index: 0 }),
			decision({ stream_id: 2, action: "keep", target_index: 0, custom_title: "Director's Cut" }),
		];
		const cmd = buildCommand(ITEM, streams, decisions);
		expect(cmd).toContain("-metadata:s:a:0 title='Director'\\''s Cut'");
		expect(cmd).not.toContain("ENG - AC3");
	});

	test("sets first kept audio as default, clears others", () => {
		const streams = [
			stream({ id: 1, type: "Video", stream_index: 0 }),
			stream({ id: 2, type: "Audio", stream_index: 1, language: "eng" }),
			stream({ id: 3, type: "Audio", stream_index: 2, language: "deu" }),
		];
		const decisions = [
			decision({ stream_id: 1, action: "keep", target_index: 0 }),
			decision({ stream_id: 2, action: "keep", target_index: 0 }),
			decision({ stream_id: 3, action: "keep", target_index: 1 }),
		];
		const cmd = buildCommand(ITEM, streams, decisions);
		expect(cmd).toContain("-disposition:a:0 default");
		expect(cmd).toContain("-disposition:a:1 0");
	});
});

describe("buildPipelineCommand", () => {
	test("emits subtitle extraction outputs and final remux in one pass", () => {
		const streams = [
			stream({ id: 1, type: "Video", stream_index: 0 }),
			stream({ id: 2, type: "Audio", stream_index: 1, codec: "aac", language: "eng" }),
			stream({ id: 3, type: "Subtitle", stream_index: 2, codec: "subrip", language: "eng" }),
		];
		const decisions = [
			decision({ stream_id: 1, action: "keep", target_index: 0 }),
			decision({ stream_id: 2, action: "keep", target_index: 0 }),
			decision({ stream_id: 3, action: "remove" }),
		];
		const { command, extractedFiles } = buildPipelineCommand(ITEM, streams, decisions);
		expect(command).toContain("-map 0:s:0");
		expect(command).toContain("-c:s copy");
		expect(command).toContain("'/movies/Test.en.srt'");
		expect(command).toContain("-map 0:v:0");
		expect(command).toContain("-map 0:a:0");
		expect(extractedFiles).toHaveLength(1);
		expect(extractedFiles[0].path).toBe("/movies/Test.en.srt");
	});

	test("transcodes incompatible audio with per-track codec flag", () => {
		const dtsItem = { ...ITEM, container: "mp4", file_path: "/movies/x.mp4" };
		const streams = [
			stream({ id: 1, type: "Video", stream_index: 0 }),
			stream({ id: 2, type: "Audio", stream_index: 1, codec: "dts", language: "eng", channels: 6 }),
		];
		const decisions = [
			decision({ stream_id: 1, action: "keep", target_index: 0 }),
			decision({ stream_id: 2, action: "keep", target_index: 0, transcode_codec: "eac3" }),
		];
		const { command } = buildPipelineCommand(dtsItem, streams, decisions);
		expect(command).toContain("-c:a:0 eac3");
		expect(command).toContain("-b:a:0 640k"); // 6 channels → 640k
	});
});

describe("predictExtractedFiles", () => {
	test("predicts sidecar paths matching extraction output", () => {
		const streams = [
			stream({ id: 1, type: "Subtitle", stream_index: 0, codec: "subrip", language: "eng" }),
			stream({ id: 2, type: "Subtitle", stream_index: 1, codec: "subrip", language: "deu", is_forced: 1 }),
		];
		const files = predictExtractedFiles(ITEM, streams);
		expect(files).toHaveLength(2);
		expect(files[0].file_path).toBe("/movies/Test.en.srt");
		expect(files[1].file_path).toBe("/movies/Test.de.forced.srt");
		expect(files[1].is_forced).toBe(true);
	});

	test("deduplicates paths with a numeric suffix", () => {
		const streams = [
			stream({ id: 1, type: "Subtitle", stream_index: 0, codec: "subrip", language: "eng" }),
			stream({ id: 2, type: "Subtitle", stream_index: 1, codec: "subrip", language: "eng" }),
		];
		const files = predictExtractedFiles(ITEM, streams);
		expect(files[0].file_path).toBe("/movies/Test.en.srt");
		expect(files[1].file_path).toBe("/movies/Test.en.2.srt");
	});
});