(function () {
  if (window.__VC_SOUNDS__) return;
  window.__VC_SOUNDS__ = true;

  const ctx = new (window.AudioContext || window.webkitAudioContext)();
  document.addEventListener("click", () => {
    if (ctx.state === "suspended") ctx.resume();
  }, { once: true });

  // ─── Synth ────────────────────────────────────────────────────────────────────
  // Warm, low, soft — layered sine + triangle with a slow attack and long decay.
  // No harsh transients. Frequencies kept in the 200-500hz range.

  function playNote(freq, startTime, duration, volume) {
    // Main body: sine (pure, smooth)
    const osc1 = ctx.createOscillator();
    const gain1 = ctx.createGain();
    osc1.type = "sine";
    osc1.frequency.value = freq;
    osc1.connect(gain1);
    gain1.connect(ctx.destination);

    // Warmth layer: triangle an octave down (adds body without brightness)
    const osc2 = ctx.createOscillator();
    const gain2 = ctx.createGain();
    osc2.type = "triangle";
    osc2.frequency.value = freq / 2;
    osc2.connect(gain2);
    gain2.connect(ctx.destination);

    // Soft attack (~30ms), smooth exponential decay
    gain1.gain.setValueAtTime(0, startTime);
    gain1.gain.linearRampToValueAtTime(volume, startTime + 0.03);
    gain1.gain.exponentialRampToValueAtTime(0.001, startTime + duration);

    gain2.gain.setValueAtTime(0, startTime);
    gain2.gain.linearRampToValueAtTime(volume * 0.4, startTime + 0.03);
    gain2.gain.exponentialRampToValueAtTime(0.001, startTime + duration);

    osc1.start(startTime); osc1.stop(startTime + duration + 0.05);
    osc2.start(startTime); osc2.stop(startTime + duration + 0.05);
  }

  // Join: two soft ascending notes, low register, gentle interval
  function playJoin() {
    if (ctx.state === "suspended") ctx.resume();
    const t = ctx.currentTime + 0.01;
    playNote(294, t,        0.35, 0.14); // D4
    playNote(370, t + 0.28, 0.45, 0.11); // F#4
  }

  // Leave: same notes descending
  function playLeave() {
    if (ctx.state === "suspended") ctx.resume();
    const t = ctx.currentTime + 0.01;
    playNote(370, t,        0.35, 0.14); // F#4
    playNote(294, t + 0.28, 0.45, 0.11); // D4
  }

  // ─── State ────────────────────────────────────────────────────────────────────

  let inVoice = false;
  let initialising = false;
  let initTimer = null;
  let globalObserver = null;

  function onSelfJoined() {
    if (inVoice) return;
    inVoice = true;
    initialising = true;
    playJoin();
    console.debug("[VCSounds] self joined");
    clearTimeout(initTimer);
    initTimer = setTimeout(() => { initialising = false; }, 1500);
  }

  function onSelfLeft() {
    if (!inVoice) return;
    inVoice = false;
    initialising = false;
    clearTimeout(initTimer);
    playLeave();
    console.debug("[VCSounds] self left");
  }

  // ─── Participant entry detection ──────────────────────────────────────────────

  function isParticipantEntry(el) {
    if (el.nodeType !== 1) return false;
    const c = el.className || "";
    return (
      c.includes("p_var(--gap-sm)") &&
      c.includes("pos_relative") &&
      c.includes("d_flex") &&
      c.includes("ai_center")
    );
  }

  // ─── Global mutation observer ─────────────────────────────────────────────────

  function startObserver() {
    if (globalObserver) return;
    globalObserver = new MutationObserver((mutations) => {
      if (!inVoice || initialising) return;
      for (const m of mutations) {
        for (const node of m.addedNodes) {
          if (isParticipantEntry(node)) {
            console.debug("[VCSounds] participant joined");
            playJoin();
          }
        }
        for (const node of m.removedNodes) {
          if (isParticipantEntry(node)) {
            console.debug("[VCSounds] participant left");
            playLeave();
          }
        }
      }
    });
    globalObserver.observe(document.body, { childList: true, subtree: true });
  }

  // ─── Fetch hook ───────────────────────────────────────────────────────────────

  const originalFetch = window.fetch;
  window.fetch = async function (...args) {
    const url = typeof args[0] === "string" ? args[0] : args[0]?.url ?? "";
    const response = await originalFetch.apply(this, args);
    if (url.includes("/join_call") && response.ok) {
      setTimeout(onSelfJoined, 300);
    }
    return response;
  };

  // ─── WebSocket hook ───────────────────────────────────────────────────────────

  const OriginalWebSocket = window.WebSocket;
  window.WebSocket = function (url, protocols) {
    const ws = protocols
      ? new OriginalWebSocket(url, protocols)
      : new OriginalWebSocket(url);
    if (typeof url === "string" && url.includes("/livekit/rtc")) {
      ws.addEventListener("close", () => onSelfLeft());
    }
    return ws;
  };
  Object.assign(window.WebSocket, OriginalWebSocket);
  window.WebSocket.prototype = OriginalWebSocket.prototype;

  startObserver();

})();