Add standalone export for Two Rivers at Moonrise

assets/scripts/games/two-rivers/systems/audio.mjs

@@ -0,0 +1,77 @@
+export class AudioDirector {
+  constructor(records, getSettings) {
+    this.getSettings = getSettings;
+    this.records = records;
+    this.sounds = new Map();
+    this.music = null;
+    this.ambience = null;
+    this.unlocked = false;
+    records.forEach((record) => {
+      this.sounds.set(record.id, new window.Howl({
+        src: record.urls || [record.url],
+        loop: record.type !== "sfx",
+        preload: record.type === "sfx",
+        volume: 0
+      }));
+    });
+    document.addEventListener("visibilitychange", () => {
+      if (document.hidden) window.Howler?.mute(true);
+      else if (this.getSettings().sound) window.Howler?.mute(false);
+    });
+  }
+
+  unlock() {
+    this.unlocked = true;
+    window.Howler?.ctx?.resume?.();
+    this.sync();
+  }
+
+  sync() {
+    const settings = this.getSettings();
+    window.Howler.volume(settings.masterVolume);
+    window.Howler.mute(!settings.sound);
+    if (this.music) this.sounds.get(this.music)?.volume(settings.musicVolume);
+    if (this.ambience) this.sounds.get(this.ambience)?.volume(settings.ambienceVolume * 0.35);
+  }
+
+  playLocation(music, ambience) {
+    if (!this.unlocked) return;
+    this.crossfade("music", music);
+    this.crossfade("ambience", ambience);
+  }
+
+  crossfade(channel, nextId) {
+    const currentId = this[channel];
+    if (currentId === nextId) return;
+    const settings = this.getSettings();
+    const target = channel === "music" ? settings.musicVolume : settings.ambienceVolume * 0.35;
+    if (currentId && this.sounds.has(currentId)) {
+      const old = this.sounds.get(currentId);
+      old.fade(old.volume(), 0, 500);
+      window.setTimeout(() => old.stop(), 520);
+    }
+    this[channel] = nextId;
+    const next = this.sounds.get(nextId);
+    if (next) {
+      next.volume(0);
+      if (!next.playing()) next.play();
+      next.fade(0, target, 700);
+    }
+  }
+
+  sfx(id) {
+    if (!this.unlocked || !this.getSettings().sound) return;
+    const sound = this.sounds.get(id);
+    if (sound) {
+      sound.volume(this.getSettings().sfxVolume);
+      sound.play();
+    }
+  }
+
+  duck(active) {
+    if (!this.music) return;
+    const sound = this.sounds.get(this.music);
+    const volume = this.getSettings().musicVolume * (active ? 0.45 : 1);
+    sound?.fade(sound.volume(), volume, 250);
+  }
+}