import { describe, expect, it } from "vitest";

import {
  TOOLCRAFT_MAX_VIDEO_ARTIFACT_BYTES,
  getToolcraftVideoExportBitrate,
  resolveToolcraftVideoEncodingPolicy,
} from "./video-encoding-policy";

describe("video encoding policy", () => {
  it("prefers AVC for MP4 and VP9 then VP8 for WebM", () => {
    const support = { avc: true, vp8: true, vp9: true };

    expect(
      resolveToolcraftVideoEncodingPolicy({
        durationSeconds: 1,
        height: 1080,
        requestedFormat: "mp4",
        support,
        width: 1920,
      }),
    ).toMatchObject({ codec: "avc", extension: ".mp4" });
    expect(
      resolveToolcraftVideoEncodingPolicy({
        durationSeconds: 1,
        height: 1080,
        requestedFormat: "webm",
        support,
        width: 1920,
      }),
    ).toMatchObject({ codec: "vp9", extension: ".webm" });
  });

  it("falls back to the other real container without changing quality", () => {
    expect(
      resolveToolcraftVideoEncodingPolicy({
        durationSeconds: 1,
        height: 2160,
        requestedFormat: "mp4",
        support: { avc: false, vp8: true, vp9: false },
        width: 3840,
      }),
    ).toEqual({
      bitrate: 12_000_000,
      codec: "vp8",
      extension: ".webm",
      mediaType: "video/webm",
    });
  });

  it("bounds bitrate and the maximum supported artifact", () => {
    expect(getToolcraftVideoExportBitrate(320, 180)).toBe(2_000_000);
    expect(getToolcraftVideoExportBitrate(3840, 2160)).toBe(12_000_000);
    const projectedBytes = (12_000_000 * 60 * 1.1) / 8;
    expect(projectedBytes).toBeLessThan(TOOLCRAFT_MAX_VIDEO_ARTIFACT_BYTES);
  });

  it("fails visibly when no timestamped codec is supported", () => {
    expect(() =>
      resolveToolcraftVideoEncodingPolicy({
        durationSeconds: 1,
        height: 1080,
        requestedFormat: "mp4",
        support: { avc: false, vp8: false, vp9: false },
        width: 1920,
      }),
    ).toThrow("timestamped video encoder");
  });
});