import { describe, expect, test, vi } from "vitest";
import { extractPeaks } from "../../../utils/player/waveform.ts";
import { calls, fail, route } from "../../fetch.ts";

describe("extractPeaks", () => {
  test("decodes once per URL and takes each block's peak", async () => {
    const data = new Float32Array([0.1, -0.5, 0.2, 0.9, -0.3, 0.4]);
    const decode = vi.fn(() => Promise.resolve({ getChannelData: () => data }));
    const close = vi.fn();
    vi.stubGlobal(
      "AudioContext",
      class {
        decodeAudioData = decode;
        close = close;
      },
    );
    route("GET /api/files/:id", () => new Response(new Uint8Array([1, 2])));

    const peaks = await extractPeaks("http://localhost:8000/api/files/w1", 3);
    expect([...peaks].map((p) => +p.toFixed(2))).toEqual([0.5, 0.9, 0.4]);
    expect(close).toHaveBeenCalled();

    await extractPeaks("http://localhost:8000/api/files/w1", 3);
    expect(decode).toHaveBeenCalledTimes(1);
    expect(calls("GET /api/files/:id")).toHaveLength(1);
  });

  test("a failed fetch throws", async () => {
    route("GET /api/files/:id", () => fail("gone", 404));
    await expect(extractPeaks("http://localhost:8000/api/files/w2", 3)).rejects
      .toThrow(/404/);
  });
});