import { existsSync } from "node:fs";
import { rm, writeFile } from "node:fs/promises";
import { join } from "node:path";
import { afterAll, beforeAll, describe, expect, it } from "vitest";
import type { FfmpegProgress } from "./ffmpeg.js";
import {
  createFfmpegProgressParser,
  detectFfmpeg,
  extractAudio,
  FfmpegError,
  ffmpegInputArgs,
  ffmpegSeconds,
  packetDurationMs,
  parseProbeOutput,
  probeMedia,
  renderPoster,
  runFfmpeg,
} from "./ffmpeg.js";
import type { TestClips } from "./media-test-support.js";
import { createTestClips } from "./media-test-support.js";

const ffmpeg = await detectFfmpeg();

describe("ffmpeg progress", () => {
  it("reports each block, tolerates split chunks and N/A times, and marks the end", () => {
    const updates: FfmpegProgress[] = [];
    const feed = createFfmpegProgressParser((update) => updates.push(update));
    feed("frame=0\nout_time_us=N/A\ntotal_size=48\nprogress=cont");
    feed("inue\nframe=75\nout_time_us=2995");
    feed("374\nout_time_ms=2995374\ntotal_size=42300\nprogress=end\n");
    expect(updates).toEqual([
      { totalSize: 48, done: false },
      { outTimeUs: 2_995_374, totalSize: 42_300, done: true },
    ]);
  });
});

describe("probe parsing", () => {
  const stream = (fields: Record<string, unknown>) => ({
    codec_type: "video",
    codec_name: "h264",
    ...fields,
  });

  it("swaps the size of rotated video and reads frame rate and audio", () => {
    const probe = parseProbeOutput(
      JSON.stringify({
        format: { duration: "12.345", format_name: "mov,mp4,m4a,3gp,3g2,mj2" },
        streams: [
          stream({
            width: 1920,
            height: 1080,
            avg_frame_rate: "30000/1001",
            sample_aspect_ratio: "1:1",
            side_data_list: [{ side_data_type: "Display Matrix", rotation: -90 }],
          }),
          { codec_type: "audio", codec_name: "aac", sample_rate: "48000", channels: 2 },
        ],
      }),
    );
    expect(probe).toEqual({
      durationMs: 12_345,
      video: {
        codec: "h264",
        width: 1080,
        height: 1920,
        rotation: 270,
        fps: 30000 / 1001,
        sampleAspectRatio: 1,
      },
      audio: { codec: "aac", sampleRate: 48_000, channels: 2 },
      hasAudio: true,
    });
  });

  it("reads legacy rotate tags, skips cover art and falls back to stream durations", () => {
    const probe = parseProbeOutput(
      JSON.stringify({
        format: { format_name: "mov" },
        streams: [
          stream({ width: 600, height: 600, disposition: { attached_pic: 1 } }),
          stream({
            width: 640,
            height: 480,
            avg_frame_rate: "0/0",
            r_frame_rate: "90000/1",
            sample_aspect_ratio: "4:3",
            tags: { rotate: "90" },
            duration: "4.5",
          }),
        ],
      }),
    );
    expect(probe.durationMs).toBe(4500);
    expect(probe.hasAudio).toBe(false);
    expect(probe.video).toMatchObject({
      width: 480,
      height: 640,
      rotation: 90,
      fps: 0,
      sampleAspectRatio: 3 / 4,
    });
  });

  it("reads the end of the last packet when the container has no duration", () => {
    expect(packetDurationMs("0.000000,0.040000\n2.960000,0.040000\nN/A,N/A\n")).toBe(3000);
    expect(packetDurationMs("")).toBe(0);
  });
});

describe("ffmpeg arguments", () => {
  it("opens inputs through the file protocol with the demuxer of their MIME type", () => {
    expect(
      ffmpegInputArgs("/a/b.webm", {
        mimeType: "video/webm",
        startSeconds: 2,
        durationSeconds: 1.5,
      }),
    ).toEqual([
      ...["-ss", "2", "-t", "1.5", "-protocol_whitelist", "file", "-f", "matroska"],
      ...["-i", "file:/a/b.webm"],
    ]);
    expect(ffmpegInputArgs("/a/b", { mimeType: "application/octet-stream" })).toEqual([
      ...["-protocol_whitelist", "file", "-i", "file:/a/b"],
    ]);
    expect(ffmpegSeconds(1e-7)).toBe("0");
    expect(ffmpegSeconds(12.34567)).toBe("12.346");
  });
});

// CI runners may not have ffmpeg; these run wherever it is installed.
describe.skipIf(!ffmpeg)("ffmpeg integration", () => {
  let clips: TestClips;

  beforeAll(async () => {
    clips = await createTestClips();
  });

  afterAll(async () => {
    if (clips) await rm(clips.dir, { recursive: true, force: true });
  });

  it("probes duration, size, frame rate and audio", async () => {
    const probe = await probeMedia(clips.landscape, { mimeType: "video/mp4" });
    expect(probe.durationMs).toBeGreaterThanOrEqual(2900);
    expect(probe.durationMs).toBeLessThanOrEqual(3100);
    expect(probe.video).toMatchObject({ codec: "h264", width: 320, height: 180, fps: 25 });
    expect(probe.hasAudio).toBe(true);
    const silent = await probeMedia(clips.silentPortrait, { mimeType: "video/mp4" });
    expect(silent.hasAudio).toBe(false);
    expect(silent.video).toMatchObject({ width: 180, height: 320 });
  });

  it("refuses a playlist disguised as an MP4 instead of following its URLs", async () => {
    const playlist = join(clips.dir, "playlist.mp4");
    await writeFile(
      playlist,
      `#EXTM3U\n#EXT-X-MEDIA-SEQUENCE:0\n#EXTINF:1.0,\nfile:${clips.srt}\n#EXT-X-ENDLIST\n`,
    );
    await expect(probeMedia(playlist, { mimeType: "video/mp4" })).rejects.toThrow(FfmpegError);
  });

  it("reports progress up to 1 for a run", async () => {
    const output = join(clips.dir, "progress.mp4");
    const fractions: number[] = [];
    await runFfmpeg(
      [
        ...ffmpegInputArgs(clips.landscape, { mimeType: "video/mp4" }),
        ...[
          "-c:v",
          "libx264",
          "-preset",
          "ultrafast",
          "-c:a",
          "aac",
          "-f",
          "mp4",
          `file:${output}`,
        ],
      ],
      { durationMs: 3000, onProgress: (fraction) => fractions.push(fraction) },
    );
    expect(fractions.at(-1)).toBe(1);
    expect(fractions).toEqual([...fractions].sort((a, b) => a - b));
    expect(existsSync(output)).toBe(true);
  });

  it("fails with the last stderr line, without directory paths, and removes outputs", async () => {
    const output = join(clips.dir, "broken.mp4");
    await writeFile(output, "partial");
    const failure = runFfmpeg(
      [
        ...ffmpegInputArgs(join(clips.dir, "missing.mp4"), { mimeType: "video/mp4" }),
        `file:${output}`,
      ],
      { outputs: [output] },
    );
    const error = await failure.catch((caught: unknown) => caught);
    expect(error).toBeInstanceOf(FfmpegError);
    expect((error as Error).message).toMatch(/^ffmpeg failed: .*missing\.mp4.*No such file/);
    expect((error as Error).message).not.toContain(clips.dir);
    expect(existsSync(output)).toBe(false);
  });

  it("kills ffmpeg on abort and removes the partial output", async () => {
    const output = join(clips.dir, "aborted.mp4");
    const controller = new AbortController();
    const run = runFfmpeg(
      [
        ...["-re", "-f", "lavfi", "-i", "testsrc=size=320x180:rate=25"],
        ...["-t", "60", "-c:v", "libx264", "-preset", "ultrafast", "-f", "mp4", `file:${output}`],
      ],
      {
        signal: controller.signal,
        durationMs: 60_000,
        onProgress: () => controller.abort(new Error("cancelled")),
        outputs: [output],
      },
    );
    await expect(run).rejects.toThrow("cancelled");
    expect(existsSync(output)).toBe(false);
  });

  it("stops when the output outgrows its cap", async () => {
    const output = join(clips.dir, "too-large.mp4");
    const run = runFfmpeg(
      [
        ...["-f", "lavfi", "-i", "testsrc=size=640x360:rate=25:duration=20"],
        ...["-c:v", "libx264", "-preset", "ultrafast", "-crf", "0", "-f", "mp4", `file:${output}`],
      ],
      { maxOutputBytes: 64 * 1024, outputs: [output] },
    );
    await expect(run).rejects.toThrow("The result would exceed 0 MB.");
    expect(existsSync(output)).toBe(false);
  });

  it("extracts 16 kHz mono WAV for transcription, optionally a range", async () => {
    const output = join(clips.dir, "speech.wav");
    await extractAudio(clips.landscape, output, { mimeType: "video/mp4", startMs: 1000 });
    const probe = await probeMedia(output, { mimeType: "audio/wav" });
    expect(probe.audio).toEqual({ codec: "pcm_s16le", sampleRate: 16_000, channels: 1 });
    expect(probe.video).toBeUndefined();
    expect(Math.abs(probe.durationMs - 2000)).toBeLessThan(100);
    await expect(
      extractAudio(clips.silentPortrait, join(clips.dir, "none.wav"), { mimeType: "video/mp4" }),
    ).rejects.toThrow("The file has no audio track.");
  });

  it("renders a poster frame, falling back to the first frame past the end", async () => {
    const poster = join(clips.dir, "poster.jpg");
    await renderPoster(clips.landscape, poster, { mimeType: "video/mp4", atMs: 60_000 });
    const probe = await probeMedia(poster);
    expect(probe.video).toMatchObject({ codec: "mjpeg", width: 320, height: 180 });
  });
});