feat(streamer): now-playing watcher with cover resolver

streamer/tests/nowplaying.test.ts

@@ -0,0 +1,103 @@
+import { describe, expect, it, beforeEach, afterEach } from "vitest";
+import { mkdtempSync, writeFileSync, rmSync, cpSync } from "node:fs";
+import { tmpdir } from "node:os";
+import { join } from "node:path";
+import { NowPlayingWatcher } from "../src/nowplaying.ts";
+
+let tmpRoot: string;
+
+beforeEach(() => {
+  tmpRoot = mkdtempSync(join(tmpdir(), "denpa-np-"));
+  cpSync("tests/fixtures/now-playing", join(tmpRoot, "now-playing"), { recursive: true });
+  cpSync("tests/fixtures/library", join(tmpRoot, "library"), { recursive: true });
+});
+
+afterEach(() => {
+  rmSync(tmpRoot, { recursive: true, force: true });
+});
+
+describe("NowPlayingWatcher", () => {
+  it("reads initial state from disk", async () => {
+    const watcher = new NowPlayingWatcher({
+      station: "minecraft",
+      nowPlayingDir: join(tmpRoot, "now-playing"),
+      libraryDir: join(tmpRoot, "library"),
+    });
+    await watcher.start();
+    const state = watcher.current();
+    expect(state).not.toBeNull();
+    expect(state!.title).toBe("Sweden");
+    expect(state!.cover_url).toMatch(/^\/cover\?path=/);
+    expect(state!.up_next).toHaveLength(1);
+    watcher.stop();
+  });
+
+  it("rewrites cover_path to /cover?path=… url", async () => {
+    const watcher = new NowPlayingWatcher({
+      station: "minecraft",
+      nowPlayingDir: join(tmpRoot, "now-playing"),
+      libraryDir: join(tmpRoot, "library"),
+    });
+    await watcher.start();
+    expect(watcher.current()!.cover_url).toContain(
+      encodeURIComponent("/library/minecraft/tracks/Volume Alpha/cover.jpg"),
+    );
+    watcher.stop();
+  });
+
+  it("emits change events on file rewrite", async () => {
+    const watcher = new NowPlayingWatcher({
+      station: "minecraft",
+      nowPlayingDir: join(tmpRoot, "now-playing"),
+      libraryDir: join(tmpRoot, "library"),
+    });
+    await watcher.start();
+
+    let changes = 0;
+    watcher.on("change", () => changes++);
+
+    const newPayload = JSON.stringify({
+      station: "minecraft",
+      title: "Pigstep",
+      artist: "Lena Raine",
+      album: "Nether Update",
+      filename: "/library/minecraft/tracks/Nether/01. Pigstep.flac",
+      duration: "148",
+      started_at: "1730358500",
+      cover_path: "",
+      up_next: [],
+    });
+    writeFileSync(join(tmpRoot, "now-playing", "minecraft.json"), newPayload);
+
+    await new Promise((r) => setTimeout(r, 200));
+    expect(changes).toBeGreaterThan(0);
+    expect(watcher.current()!.title).toBe("Pigstep");
+    watcher.stop();
+  });
+
+  it("falls back to station cover when track cover missing", async () => {
+    const payload = JSON.stringify({
+      station: "minecraft",
+      title: "Untagged Track",
+      artist: "?",
+      album: "?",
+      filename: "/library/minecraft/tracks/UnknownAlbum/track.flac",
+      duration: "120",
+      started_at: "1730358000",
+      cover_path: "",
+      up_next: [],
+    });
+    writeFileSync(join(tmpRoot, "now-playing", "minecraft.json"), payload);
+
+    const watcher = new NowPlayingWatcher({
+      station: "minecraft",
+      nowPlayingDir: join(tmpRoot, "now-playing"),
+      libraryDir: join(tmpRoot, "library"),
+    });
+    await watcher.start();
+    expect(watcher.current()!.cover_url).toContain(
+      encodeURIComponent("/library/minecraft/cover.jpg"),
+    );
+    watcher.stop();
+  });
+});