// ── State ─────────────────────────────────────────────────────────────────────
const _t = {
  mode:            'pomodoro',  // 'pomodoro' | 'freeflow'
  phase:           'work',      // 'work' | 'break'
  secondsElapsed:  0,
  running:         false,
  intervalId:      null,
};

const _TIMER_LS_KEY = 'focus_buddy_timer';

function _saveTimerState() {
  const workEl  = document.getElementById('work-dur');
  const breakEl = document.getElementById('break-dur');
  try {
    localStorage.setItem(_TIMER_LS_KEY, JSON.stringify({
      mode:           _t.mode,
      phase:          _t.phase,
      secondsElapsed: _t.secondsElapsed,
      workDur:        workEl?.value  || '25',
      breakDur:       breakEl?.value || '5',
    }));
  } catch (_) {}
}

function _restoreTimerState() {
  try {
    const saved = JSON.parse(localStorage.getItem(_TIMER_LS_KEY) || 'null');
    if (!saved) return;
    _t.mode           = saved.mode  || 'pomodoro';
    _t.phase          = saved.phase || 'work';
    _t.secondsElapsed = saved.secondsElapsed || 0;
    const workEl  = document.getElementById('work-dur');
    const breakEl = document.getElementById('break-dur');
    if (workEl)  workEl.value  = saved.workDur  || '25';
    if (breakEl) breakEl.value = saved.breakDur || '5';
  } catch (_) {}
}

// ── Helpers ───────────────────────────────────────────────────────────────────
function _workSecs()  { return (parseInt(document.getElementById('work-dur')?.value)  || 25) * 60; }
function _breakSecs() { return (parseInt(document.getElementById('break-dur')?.value) || 5)  * 60; }

function _targetSecs() {
  if (_t.mode === 'freeflow') return Infinity;
  return _t.phase === 'work' ? _workSecs() : _breakSecs();
}

function _fmt(secs) {
  const m = Math.floor(secs / 60).toString().padStart(2, '0');
  const s = (secs % 60).toString().padStart(2, '0');
  return `${m}:${s}`;
}

function _setDisplay() {
  const elapsed = document.getElementById('timer-elapsed');
  const target  = document.getElementById('timer-target');
  if (elapsed) elapsed.textContent = _fmt(_t.secondsElapsed);
  if (target) {
    if (_t.mode === 'pomodoro') {
      target.textContent = ' / ' + _fmt(_t.phase === 'work' ? _workSecs() : _breakSecs());
    } else {
      target.textContent = '';
    }
  }
}

function _setPhaseLabel(text) {
  const el = document.getElementById('timer-phase');
  if (el) el.textContent = text;
}

function _setBreakStyle(isBreak) {
  document.getElementById('timer-display')?.classList.toggle('break-phase', isBreak);
}

function _setModeButtonActive(mode) {
  document.getElementById('btn-pomodoro')?.classList.toggle('active', mode === 'pomodoro');
  document.getElementById('btn-freeflow')?.classList.toggle('active', mode === 'freeflow');
}

function _updateStartBtn() {
  const btn = document.getElementById('btn-start-stop');
  if (!btn) return;
  if (_t.running) {
    btn.textContent = '■ Stop';
    btn.classList.add('stop-btn');
    btn.classList.remove('start-btn');
  } else {
    btn.textContent = '▶ Start';
    btn.classList.remove('stop-btn');
    btn.classList.add('start-btn');
  }
  const disabled = _t.running;
  document.getElementById('btn-pomodoro')?.toggleAttribute('disabled', disabled);
  document.getElementById('btn-freeflow')?.toggleAttribute('disabled', disabled);
  // Drive the 3D avatar's base animation off the running state and phase.
  if (window.avatarSetBase) {
    if (_t.running) {
      window.avatarSetBase(_t.phase === 'break' ? 'rest' : 'working');
    } else {
      window.avatarSetBase('idle');
    }
  }
}

// ── Chime (Web Audio API) ─────────────────────────────────────────────────────
function _playChime() {
  try {
    const ctx = new (window.AudioContext || window.webkitAudioContext)();
    [[880, 0, 0.6], [1109, 0.15, 0.4], [880, 0.4, 0.25]].forEach(([freq, delay, vol]) => {
      const osc  = ctx.createOscillator();
      const gain = ctx.createGain();
      osc.connect(gain);
      gain.connect(ctx.destination);
      osc.type = 'sine';
      osc.frequency.value = freq;
      const t = ctx.currentTime + delay;
      gain.gain.setValueAtTime(vol, t);
      gain.gain.exponentialRampToValueAtTime(0.001, t + 1.8);
      osc.start(t);
      osc.stop(t + 1.9);
    });
  } catch (_) {}
}

// ── Core timer logic ──────────────────────────────────────────────────────────
function _tick() {
  _t.secondsElapsed++;
  _setDisplay();
  if (_t.secondsElapsed % 30 === 0) _saveTimerState();

  if (_t.secondsElapsed < _targetSecs()) return;

  // Reached target
  _stopInterval();
  _onComplete();
}

function _stopInterval() {
  if (_t.intervalId !== null) {
    clearInterval(_t.intervalId);
    _t.intervalId = null;
  }
  _t.running = false;
  _updateStartBtn();
  _saveTimerState();
}

function _onComplete() {
  _playChime();
  if (window.avatarPlay) window.avatarPlay('celebrate');

  const el = document.getElementById('timer-display');
  if (el) {
    el.classList.add('ringing');
    setTimeout(() => el.classList.remove('ringing'), 3000);
  }

  if (_t.mode === 'pomodoro') {
    if (_t.phase === 'work') {
      bridgeSend('timer_complete', { mode: 'pomodoro', phase: 'work' });
      _t.phase = 'break';
      _t.secondsElapsed = 0;
      _setPhaseLabel('☕ Break Time');
      _setBreakStyle(true);
    } else {
      bridgeSend('timer_complete', { mode: 'pomodoro', phase: 'break' });
      _t.phase = 'work';
      _t.secondsElapsed = 0;
      _setPhaseLabel('⚔️ Work Session');
      _setBreakStyle(false);
    }
  } else {
    bridgeSend('timer_complete', { mode: 'freeflow', phase: 'work' });
    _t.secondsElapsed = 0;
    _setPhaseLabel('🌊 Free Flow');
  }

  _setDisplay();
}

// ── Public API ────────────────────────────────────────────────────────────────
function timerToggle() {
  if (_t.running) {
    // Capture state before stopping
    const elapsedAtStop = _t.secondsElapsed;
    const phaseAtStop   = _t.phase;
    const modeAtStop    = _t.mode;
    const targetAtStop  = _t.mode === 'pomodoro'
      ? (phaseAtStop === 'work' ? _workSecs() : _breakSecs())
      : null;

    _stopInterval();

    // Send XP event for partial work completed
    if (elapsedAtStop > 0) {
      if (phaseAtStop === 'work' && window.avatarPlay) window.avatarPlay('celebrate');
      const payload = { mode: modeAtStop, phase: phaseAtStop, seconds_elapsed: elapsedAtStop };
      if (targetAtStop !== null) payload.target_secs = targetAtStop;
      bridgeSend('timer_stop', payload);
    }

    // Reset display to 00:00, back to work phase
    _t.phase          = 'work';
    _t.secondsElapsed = 0;
    _setBreakStyle(false);
    _setDisplay();
    _setPhaseLabel(modeAtStop === 'pomodoro' ? '⚔️ Work Session' : '🌊 Free Flow');
    _saveTimerState();
  } else {
    _t.running = true;
    _t.intervalId = setInterval(_tick, 1000);
    _updateStartBtn();
    _saveTimerState();
  }
}

function timerReset() {
  _stopInterval();
  _t.phase = 'work';
  _t.secondsElapsed = 0;
  _setBreakStyle(false);
  _setDisplay();
  _setPhaseLabel(_t.mode === 'pomodoro' ? '⚔️ Work Session' : '🌊 Free Flow');
  _saveTimerState();
}

function setTimerMode(mode) {
  if (_t.running) _stopInterval();
  _t.mode = mode;
  _t.phase = 'work';
  _t.secondsElapsed = 0;
  _setModeButtonActive(mode);
  _setBreakStyle(false);
  _setDisplay();

  const isFreeflow = mode === 'freeflow';
  const workConfig  = document.getElementById('work-config');
  const breakConfig = document.getElementById('break-config');
  if (workConfig)  workConfig.style.display  = isFreeflow ? 'none' : '';
  if (breakConfig) breakConfig.style.display = isFreeflow ? 'none' : '';

  _setPhaseLabel(mode === 'pomodoro' ? '⚔️ Work Session' : '🌊 Free Flow');
  _saveTimerState();
}

// ── LLM-controlled API ────────────────────────────────────────────────────────
function timerStart(durationMinutes, mode) {
  if (_t.running) _stopInterval();
  setTimerMode(mode || 'pomodoro');
  if ((mode || 'pomodoro') === 'pomodoro' && durationMinutes) {
    const el = document.getElementById('work-dur');
    if (el) el.value = durationMinutes;
  }
  _t.running = true;
  _t.intervalId = setInterval(_tick, 1000);
  _updateStartBtn();
}

function timerStop() {
  if (_t.running) _stopInterval();
}

function timerAddMinutes(mins) {
  _t.secondsElapsed = Math.max(0, _t.secondsElapsed + mins * 60);
  _setDisplay();
  _saveTimerState();
}

// Export public API for inline onclick handlers
window.timerToggle = timerToggle;
window.timerReset = timerReset;
window.setTimerMode = setTimerMode;
window.timerStart = timerStart;
window.timerStop = timerStop;
window.timerAddMinutes = timerAddMinutes;

// ── Init ──────────────────────────────────────────────────────────────────────
function _initTimer() {
  if (!document.getElementById('timer-elapsed')) {
    setTimeout(_initTimer, 150);
    return;
  }
  _restoreTimerState();
  _setDisplay();
  _setModeButtonActive(_t.mode);
  _setBreakStyle(_t.phase === 'break');
  _setPhaseLabel(_t.mode === 'freeflow' ? '🌊 Free Flow' : _t.phase === 'break' ? '☕ Break Time' : '⚔️ Work Session');

  const isFreeflow = _t.mode === 'freeflow';
  const workConfig  = document.getElementById('work-config');
  const breakConfig = document.getElementById('break-config');
  if (workConfig)  workConfig.style.display  = isFreeflow ? 'none' : '';
  if (breakConfig) breakConfig.style.display = isFreeflow ? 'none' : '';

  _updateStartBtn();
}

_initTimer();