audio-ui/components/editor/AudioEditor.tsx

'use client';

import * as React from 'react';
import { Music, Plus, Upload, Trash2, Settings, Download } from 'lucide-react';
import { PlaybackControls } from './PlaybackControls';
import { MasterControls } from '@/components/controls/MasterControls';
import { FrequencyAnalyzer } from '@/components/analysis/FrequencyAnalyzer';
import { Spectrogram } from '@/components/analysis/Spectrogram';
import { PhaseCorrelationMeter } from '@/components/analysis/PhaseCorrelationMeter';
import { LUFSMeter } from '@/components/analysis/LUFSMeter';
import { AudioStatistics } from '@/components/analysis/AudioStatistics';
import { ThemeToggle } from '@/components/layout/ThemeToggle';
import { CommandPalette } from '@/components/ui/CommandPalette';
import { GlobalSettingsDialog } from '@/components/settings/GlobalSettingsDialog';
import { ExportDialog, type ExportSettings } from '@/components/dialogs/ExportDialog';
import { Button } from '@/components/ui/Button';
import type { CommandAction } from '@/components/ui/CommandPalette';
import { useMultiTrack } from '@/lib/hooks/useMultiTrack';
import { useMultiTrackPlayer } from '@/lib/hooks/useMultiTrackPlayer';
import { useEffectChain } from '@/lib/hooks/useEffectChain';
import { useToast } from '@/components/ui/Toast';
import { TrackList } from '@/components/tracks/TrackList';
import { ImportTrackDialog } from '@/components/tracks/ImportTrackDialog';
import { formatDuration } from '@/lib/audio/decoder';
import { useHistory } from '@/lib/hooks/useHistory';
import { useRecording } from '@/lib/hooks/useRecording';
import type { EffectType } from '@/lib/audio/effects/chain';
import {
  createMultiTrackCutCommand,
  createMultiTrackCopyCommand,
  createMultiTrackDeleteCommand,
  createMultiTrackPasteCommand,
  createMultiTrackDuplicateCommand,
} from '@/lib/history/commands/multi-track-edit-command';
import { extractBufferSegment } from '@/lib/audio/buffer-utils';
import { mixTracks, getMaxTrackDuration } from '@/lib/audio/track-utils';
import { audioBufferToWav, audioBufferToMp3, downloadArrayBuffer } from '@/lib/audio/export';

export function AudioEditor() {
  const [importDialogOpen, setImportDialogOpen] = React.useState(false);
  const [selectedTrackId, setSelectedTrackId] = React.useState<string | null>(null);
  const [zoom, setZoom] = React.useState(1);
  const [masterVolume, setMasterVolume] = React.useState(0.8);
  const [masterPan, setMasterPan] = React.useState(0);
  const [isMasterMuted, setIsMasterMuted] = React.useState(false);
  const [clipboard, setClipboard] = React.useState<AudioBuffer | null>(null);
  const [recordingTrackId, setRecordingTrackId] = React.useState<string | null>(null);
  const [punchInEnabled, setPunchInEnabled] = React.useState(false);
  const [punchInTime, setPunchInTime] = React.useState(0);
  const [punchOutTime, setPunchOutTime] = React.useState(0);
  const [overdubEnabled, setOverdubEnabled] = React.useState(false);
  const [settingsDialogOpen, setSettingsDialogOpen] = React.useState(false);
  const [exportDialogOpen, setExportDialogOpen] = React.useState(false);
  const [isExporting, setIsExporting] = React.useState(false);
  const [analyzerView, setAnalyzerView] = React.useState<'frequency' | 'spectrogram' | 'phase' | 'lufs' | 'stats'>('frequency');

  const { addToast } = useToast();

  // Command history for undo/redo
  const { execute: executeCommand, undo, redo, state: historyState } = useHistory();
  const canUndo = historyState.canUndo;
  const canRedo = historyState.canRedo;

  // Recording hook
  const {
    state: recordingState,
    settings: recordingSettings,
    startRecording,
    stopRecording,
    requestPermission,
    setInputGain,
    setRecordMono,
    setSampleRate,
  } = useRecording();

  // Multi-track hooks
  const {
    tracks,
    addTrack: addTrackOriginal,
    addTrackFromBuffer: addTrackFromBufferOriginal,
    removeTrack,
    updateTrack,
    clearTracks,
  } = useMultiTrack();

  // Track whether we should auto-select on next add (when project is empty)
  const shouldAutoSelectRef = React.useRef(true);

  React.useEffect(() => {
    // Update auto-select flag based on track count
    shouldAutoSelectRef.current = tracks.length === 0;
  }, [tracks.length]);

  // Wrap addTrack to auto-select first track when adding to empty project
  const addTrack = React.useCallback((name?: string) => {
    const shouldAutoSelect = shouldAutoSelectRef.current;
    const track = addTrackOriginal(name);
    if (shouldAutoSelect) {
      setSelectedTrackId(track.id);
      shouldAutoSelectRef.current = false; // Only auto-select once
    }
    return track;
  }, [addTrackOriginal]);

  // Wrap addTrackFromBuffer to auto-select first track when adding to empty project
  const addTrackFromBuffer = React.useCallback((buffer: AudioBuffer, name?: string) => {
    console.log(`[AudioEditor] addTrackFromBuffer wrapper called: ${name}, shouldAutoSelect: ${shouldAutoSelectRef.current}`);
    const shouldAutoSelect = shouldAutoSelectRef.current;
    const track = addTrackFromBufferOriginal(buffer, name);
    console.log(`[AudioEditor] Track created: ${track.name} (${track.id})`);
    if (shouldAutoSelect) {
      console.log(`[AudioEditor] Auto-selecting track: ${track.id}`);
      setSelectedTrackId(track.id);
      shouldAutoSelectRef.current = false; // Only auto-select once
    }
    return track;
  }, [addTrackFromBufferOriginal]);

  // Track which parameters are being touched (for touch/latch modes)
  const [touchedParameters, setTouchedParameters] = React.useState<Set<string>>(new Set());
  const [latchTriggered, setLatchTriggered] = React.useState<Set<string>>(new Set());

  // Track last recorded values to detect changes
  const lastRecordedValuesRef = React.useRef<Map<string, { value: number; time: number }>>(new Map());

  // Automation recording callback
  const handleAutomationRecording = React.useCallback((
    trackId: string,
    laneId: string,
    currentTime: number,
    value: number
  ) => {
    const track = tracks.find(t => t.id === trackId);
    if (!track) return;

    const lane = track.automation.lanes.find(l => l.id === laneId);
    if (!lane) return;

    const paramKey = `${trackId}-${laneId}`;
    let shouldRecord = false;

    // Determine if we should record based on mode
    switch (lane.mode) {
      case 'write':
        // Always record in write mode
        shouldRecord = true;
        break;

      case 'touch':
        // Only record when parameter is being touched
        shouldRecord = touchedParameters.has(paramKey);
        break;

      case 'latch':
        // Record from first touch until stop
        if (touchedParameters.has(paramKey)) {
          setLatchTriggered(prev => new Set(prev).add(paramKey));
        }
        shouldRecord = latchTriggered.has(paramKey);
        break;

      default:
        shouldRecord = false;
    }

    if (!shouldRecord) return;

    // Throttle recording to avoid creating too many automation points
    // This doesn't prevent recording, just limits frequency
    const lastRecorded = lastRecordedValuesRef.current.get(paramKey);

    if (lastRecorded && currentTime - lastRecorded.time < 0.1) {
      // Check if value has changed significantly
      const valueChanged = Math.abs(lastRecorded.value - value) > 0.001;
      if (!valueChanged) {
        // Skip if value hasn't changed and we recorded recently
        return;
      }
    }

    // Update last recorded value
    lastRecordedValuesRef.current.set(paramKey, { value, time: currentTime });

    // Create new automation point
    const newPoint = {
      id: `point-${Date.now()}-${Math.random().toString(36).substr(2, 9)}`,
      time: currentTime,
      value,
      curve: 'linear' as const,
    };

    // In write mode, remove existing points near this time (overwrites)
    const updatedPoints = lane.mode === 'write'
      ? [...lane.points.filter(p => Math.abs(p.time - currentTime) > 0.05), newPoint]
      : [...lane.points, newPoint];

    updatedPoints.sort((a, b) => a.time - b.time);

    // Update the lane with new points
    const updatedLanes = track.automation.lanes.map(l =>
      l.id === laneId ? { ...l, points: updatedPoints } : l
    );

    updateTrack(trackId, {
      automation: {
        ...track.automation,
        lanes: updatedLanes,
      },
    });
  }, [tracks, updateTrack, touchedParameters, latchTriggered]);

  // Helper to mark parameter as touched (for touch/latch modes)
  const setParameterTouched = React.useCallback((trackId: string, laneId: string, touched: boolean) => {
    const paramKey = `${trackId}-${laneId}`;
    setTouchedParameters(prev => {
      const next = new Set(prev);
      if (touched) {
        next.add(paramKey);
      } else {
        next.delete(paramKey);
      }
      return next;
    });
  }, []);

  const {
    isPlaying,
    currentTime,
    duration,
    trackLevels,
    masterPeakLevel,
    masterRmsLevel,
    masterIsClipping,
    masterAnalyser,
    resetClipIndicator,
    play,
    pause,
    stop,
    seek,
    togglePlayPause,
  } = useMultiTrackPlayer(tracks, masterVolume, handleAutomationRecording);

  // Reset latch triggered state when playback stops
  React.useEffect(() => {
    if (!isPlaying) {
      setLatchTriggered(new Set());
      lastRecordedValuesRef.current.clear();
    }
  }, [isPlaying]);

  // Record effect parameter values while touched
  React.useEffect(() => {
    if (!isPlaying) return;

    const recordEffectParams = () => {
      const time = currentTime;

      touchedParameters.forEach(paramKey => {
        const [trackId, laneId] = paramKey.split('-');
        const track = tracks.find(t => t.id === trackId);
        if (!track) return;

        const lane = track.automation.lanes.find(l => l.id === laneId);
        if (!lane || !lane.parameterId.startsWith('effect.')) return;

        // Parse effect parameter ID: effect.{effectId}.{paramName}
        const parts = lane.parameterId.split('.');
        if (parts.length !== 3) return;

        const effectId = parts[1];
        const paramName = parts[2];

        const effect = track.effectChain.effects.find(e => e.id === effectId);
        if (!effect || !effect.parameters) return;

        const currentValue = (effect.parameters as any)[paramName];
        if (currentValue === undefined) return;

        // Normalize value to 0-1 range
        const range = lane.valueRange.max - lane.valueRange.min;
        const normalizedValue = (currentValue - lane.valueRange.min) / range;

        // Record the automation
        handleAutomationRecording(trackId, laneId, time, normalizedValue);
      });
    };

    const interval = setInterval(recordEffectParams, 50); // Record every 50ms while touched
    return () => clearInterval(interval);
  }, [isPlaying, currentTime, touchedParameters, tracks, handleAutomationRecording]);

  // Master effect chain
  const {
    chain: masterEffectChain,
    presets: masterEffectPresets,
    toggleEffectEnabled: toggleMasterEffect,
    removeEffect: removeMasterEffect,
    reorder: reorderMasterEffects,
    clearChain: clearMasterChain,
    savePreset: saveMasterPreset,
    loadPresetToChain: loadMasterPreset,
    deletePreset: deleteMasterPreset,
  } = useEffectChain();

  // Multi-track handlers
  const handleImportTracks = () => {
    setImportDialogOpen(true);
  };

  const handleImportTrack = (buffer: AudioBuffer, name: string) => {
    console.log(`[AudioEditor] handleImportTrack called: ${name}`);
    addTrackFromBuffer(buffer, name);
  };

  const handleClearTracks = () => {
    clearTracks();
    setSelectedTrackId(null);
    addToast({
      title: 'Tracks Cleared',
      description: 'All tracks have been removed',
      variant: 'info',
      duration: 2000,
    });
  };

  const handleRemoveTrack = (trackId: string) => {
    removeTrack(trackId);
    if (selectedTrackId === trackId) {
      setSelectedTrackId(null);
    }
  };

  // Per-track effect chain handlers
  const handleToggleTrackEffect = (effectId: string) => {
    if (!selectedTrack) return;
    const updatedChain = {
      ...selectedTrack.effectChain,
      effects: selectedTrack.effectChain.effects.map((e) =>
        e.id === effectId ? { ...e, enabled: !e.enabled } : e
      ),
    };
    updateTrack(selectedTrack.id, { effectChain: updatedChain });
  };

  const handleRemoveTrackEffect = (effectId: string) => {
    if (!selectedTrack) return;
    const updatedChain = {
      ...selectedTrack.effectChain,
      effects: selectedTrack.effectChain.effects.filter((e) => e.id !== effectId),
    };
    updateTrack(selectedTrack.id, { effectChain: updatedChain });
  };

  const handleReorderTrackEffects = (fromIndex: number, toIndex: number) => {
    if (!selectedTrack) return;
    const effects = [...selectedTrack.effectChain.effects];
    const [removed] = effects.splice(fromIndex, 1);
    effects.splice(toIndex, 0, removed);
    const updatedChain = {
      ...selectedTrack.effectChain,
      effects,
    };
    updateTrack(selectedTrack.id, { effectChain: updatedChain });
  };

  const handleClearTrackChain = () => {
    if (!selectedTrack) return;
    const updatedChain = {
      ...selectedTrack.effectChain,
      effects: [],
    };
    updateTrack(selectedTrack.id, { effectChain: updatedChain });
  };

  // Effects Panel handlers
  const handleAddEffect = React.useCallback((effectType: EffectType) => {
    if (!selectedTrackId) return;
    const track = tracks.find((t) => t.id === selectedTrackId);
    if (!track) return;

    // Import createEffect and EFFECT_NAMES dynamically
    import('@/lib/audio/effects/chain').then(({ createEffect, EFFECT_NAMES }) => {
      const newEffect = createEffect(effectType, EFFECT_NAMES[effectType]);
      const updatedChain = {
        ...track.effectChain,
        effects: [...track.effectChain.effects, newEffect],
      };
      updateTrack(selectedTrackId, { effectChain: updatedChain });
    });
  }, [selectedTrackId, tracks, updateTrack]);

  const handleToggleEffect = React.useCallback((effectId: string) => {
    if (!selectedTrackId) return;
    const track = tracks.find((t) => t.id === selectedTrackId);
    if (!track) return;

    const updatedChain = {
      ...track.effectChain,
      effects: track.effectChain.effects.map((e) =>
        e.id === effectId ? { ...e, enabled: !e.enabled } : e
      ),
    };
    updateTrack(selectedTrackId, { effectChain: updatedChain });
  }, [selectedTrackId, tracks, updateTrack]);

  const handleRemoveEffect = React.useCallback((effectId: string) => {
    if (!selectedTrackId) return;
    const track = tracks.find((t) => t.id === selectedTrackId);
    if (!track) return;

    const updatedChain = {
      ...track.effectChain,
      effects: track.effectChain.effects.filter((e) => e.id !== effectId),
    };
    updateTrack(selectedTrackId, { effectChain: updatedChain });
  }, [selectedTrackId, tracks, updateTrack]);

  const handleUpdateEffect = React.useCallback((effectId: string, parameters: any) => {
    if (!selectedTrackId) return;
    const track = tracks.find((t) => t.id === selectedTrackId);
    if (!track) return;

    const updatedChain = {
      ...track.effectChain,
      effects: track.effectChain.effects.map((e) =>
        e.id === effectId ? { ...e, parameters } : e
      ),
    };
    updateTrack(selectedTrackId, { effectChain: updatedChain });
  }, [selectedTrackId, tracks, updateTrack]);

  const handleToggleEffectExpanded = React.useCallback((effectId: string) => {
    if (!selectedTrackId) return;
    const track = tracks.find((t) => t.id === selectedTrackId);
    if (!track) return;

    const updatedChain = {
      ...track.effectChain,
      effects: track.effectChain.effects.map((e) =>
        e.id === effectId ? { ...e, expanded: !e.expanded } : e
      ),
    };
    updateTrack(selectedTrackId, { effectChain: updatedChain });
  }, [selectedTrackId, tracks, updateTrack]);

  // Preserve effects panel state - don't auto-open/close on track selection

  // Selection handler
  const handleSelectionChange = (trackId: string, selection: { start: number; end: number } | null) => {
    updateTrack(trackId, { selection });
  };

  // Recording handlers
  const handleToggleRecordEnable = React.useCallback((trackId: string) => {
    const track = tracks.find((t) => t.id === trackId);
    if (!track) return;

    // Toggle record enable
    updateTrack(trackId, { recordEnabled: !track.recordEnabled });
  }, [tracks, updateTrack]);

  const handleStartRecording = React.useCallback(async () => {
    // Find first armed track
    const armedTrack = tracks.find((t) => t.recordEnabled);
    if (!armedTrack) {
      addToast({
        title: 'No Track Armed',
        description: 'Please arm a track for recording first',
        variant: 'warning',
        duration: 3000,
      });
      return;
    }

    // Request permission if needed
    const hasPermission = await requestPermission();
    if (!hasPermission) {
      addToast({
        title: 'Microphone Access Denied',
        description: 'Please allow microphone access to record',
        variant: 'error',
        duration: 3000,
      });
      return;
    }

    try {
      await startRecording();
      setRecordingTrackId(armedTrack.id);
      addToast({
        title: 'Recording Started',
        description: `Recording to ${armedTrack.name}`,
        variant: 'success',
        duration: 2000,
      });
    } catch (error) {
      console.error('Failed to start recording:', error);
      addToast({
        title: 'Recording Failed',
        description: 'Failed to start recording',
        variant: 'error',
        duration: 3000,
      });
    }
  }, [tracks, startRecording, requestPermission, addToast]);

  const handleStopRecording = React.useCallback(async () => {
    if (!recordingTrackId) return;

    try {
      const recordedBuffer = await stopRecording();

      if (recordedBuffer) {
        const track = tracks.find((t) => t.id === recordingTrackId);

        // Check if overdub mode is enabled and track has existing audio
        if (overdubEnabled && track?.audioBuffer) {
          // Mix recorded audio with existing audio
          const audioContext = new AudioContext();
          const existingBuffer = track.audioBuffer;

          // Create a new buffer that's long enough for both
          const maxDuration = Math.max(existingBuffer.duration, recordedBuffer.duration);
          const maxChannels = Math.max(existingBuffer.numberOfChannels, recordedBuffer.numberOfChannels);
          const mixedBuffer = audioContext.createBuffer(
            maxChannels,
            Math.floor(maxDuration * existingBuffer.sampleRate),
            existingBuffer.sampleRate
          );

          // Mix each channel
          for (let channel = 0; channel < maxChannels; channel++) {
            const mixedData = mixedBuffer.getChannelData(channel);
            const existingData = channel < existingBuffer.numberOfChannels
              ? existingBuffer.getChannelData(channel)
              : new Float32Array(mixedData.length);
            const recordedData = channel < recordedBuffer.numberOfChannels
              ? recordedBuffer.getChannelData(channel)
              : new Float32Array(mixedData.length);

            // Mix the samples (average them to avoid clipping)
            for (let i = 0; i < mixedData.length; i++) {
              const existingSample = i < existingData.length ? existingData[i] : 0;
              const recordedSample = i < recordedData.length ? recordedData[i] : 0;
              mixedData[i] = (existingSample + recordedSample) / 2;
            }
          }

          updateTrack(recordingTrackId, { audioBuffer: mixedBuffer });

          addToast({
            title: 'Recording Complete (Overdub)',
            description: `Mixed ${recordedBuffer.duration.toFixed(2)}s with existing audio`,
            variant: 'success',
            duration: 3000,
          });
        } else {
          // Normal mode - replace existing audio
          updateTrack(recordingTrackId, { audioBuffer: recordedBuffer });

          addToast({
            title: 'Recording Complete',
            description: `Recorded ${recordedBuffer.duration.toFixed(2)}s of audio`,
            variant: 'success',
            duration: 3000,
          });
        }
      }

      setRecordingTrackId(null);
    } catch (error) {
      console.error('Failed to stop recording:', error);
      addToast({
        title: 'Recording Error',
        description: 'Failed to save recording',
        variant: 'error',
        duration: 3000,
      });
      setRecordingTrackId(null);
    }
  }, [recordingTrackId, stopRecording, updateTrack, addToast, overdubEnabled, tracks]);

  // Edit handlers
  const handleCut = React.useCallback(() => {
    const track = tracks.find((t) => t.selection);
    if (!track || !track.audioBuffer || !track.selection) return;

    // Extract to clipboard
    const extracted = extractBufferSegment(
      track.audioBuffer,
      track.selection.start,
      track.selection.end
    );
    setClipboard(extracted);

    // Execute cut command
    const command = createMultiTrackCutCommand(
      track.id,
      track.audioBuffer,
      track.selection,
      (trackId, buffer, selection) => {
        updateTrack(trackId, { audioBuffer: buffer, selection });
      }
    );
    executeCommand(command);

    addToast({
      title: 'Cut',
      description: 'Selection cut to clipboard',
      variant: 'success',
      duration: 2000,
    });
  }, [tracks, executeCommand, updateTrack, addToast]);

  const handleCopy = React.useCallback(() => {
    const track = tracks.find((t) => t.selection);
    if (!track || !track.audioBuffer || !track.selection) return;

    // Extract to clipboard
    const extracted = extractBufferSegment(
      track.audioBuffer,
      track.selection.start,
      track.selection.end
    );
    setClipboard(extracted);

    // Execute copy command (doesn't modify buffer, just for undo history)
    const command = createMultiTrackCopyCommand(
      track.id,
      track.audioBuffer,
      track.selection,
      (trackId, buffer, selection) => {
        updateTrack(trackId, { audioBuffer: buffer, selection });
      }
    );
    executeCommand(command);

    addToast({
      title: 'Copy',
      description: 'Selection copied to clipboard',
      variant: 'success',
      duration: 2000,
    });
  }, [tracks, executeCommand, updateTrack, addToast]);

  const handlePaste = React.useCallback(() => {
    if (!clipboard || !selectedTrackId) return;

    const track = tracks.find((t) => t.id === selectedTrackId);
    if (!track) return;

    // Paste at current time or at end of buffer
    const pastePosition = currentTime || track.audioBuffer?.duration || 0;

    const command = createMultiTrackPasteCommand(
      track.id,
      track.audioBuffer,
      clipboard,
      pastePosition,
      (trackId, buffer, selection) => {
        updateTrack(trackId, { audioBuffer: buffer, selection });
      }
    );
    executeCommand(command);

    addToast({
      title: 'Paste',
      description: 'Clipboard content pasted',
      variant: 'success',
      duration: 2000,
    });
  }, [clipboard, selectedTrackId, tracks, currentTime, executeCommand, updateTrack, addToast]);

  const handleDelete = React.useCallback(() => {
    const track = tracks.find((t) => t.selection);
    if (!track || !track.audioBuffer || !track.selection) return;

    const command = createMultiTrackDeleteCommand(
      track.id,
      track.audioBuffer,
      track.selection,
      (trackId, buffer, selection) => {
        updateTrack(trackId, { audioBuffer: buffer, selection });
      }
    );
    executeCommand(command);

    addToast({
      title: 'Delete',
      description: 'Selection deleted',
      variant: 'success',
      duration: 2000,
    });
  }, [tracks, executeCommand, updateTrack, addToast]);

  const handleDuplicate = React.useCallback(() => {
    const track = tracks.find((t) => t.selection);
    if (!track || !track.audioBuffer || !track.selection) return;

    const command = createMultiTrackDuplicateCommand(
      track.id,
      track.audioBuffer,
      track.selection,
      (trackId, buffer, selection) => {
        updateTrack(trackId, { audioBuffer: buffer, selection });
      }
    );
    executeCommand(command);

    addToast({
      title: 'Duplicate',
      description: 'Selection duplicated',
      variant: 'success',
      duration: 2000,
    });
  }, [tracks, executeCommand, updateTrack, addToast]);

  // Export handler
  const handleExport = React.useCallback(async (settings: ExportSettings) => {
    if (tracks.length === 0) {
      addToast({
        title: 'No Tracks',
        description: 'Add some tracks before exporting',
        variant: 'warning',
        duration: 3000,
      });
      return;
    }

    setIsExporting(true);

    try {
      const sampleRate = tracks[0]?.audioBuffer?.sampleRate || 44100;

      // Helper function to convert and download a buffer
      const convertAndDownload = async (buffer: AudioBuffer, filename: string) => {
        let exportedBuffer: ArrayBuffer;
        let mimeType: string;
        let fileExtension: string;

        if (settings.format === 'mp3') {
          exportedBuffer = await audioBufferToMp3(buffer, {
            format: 'mp3',
            bitrate: settings.bitrate,
            normalize: settings.normalize,
          });
          mimeType = 'audio/mpeg';
          fileExtension = 'mp3';
        } else {
          // WAV export
          exportedBuffer = audioBufferToWav(buffer, {
            format: 'wav',
            bitDepth: settings.bitDepth,
            normalize: settings.normalize,
          });
          mimeType = 'audio/wav';
          fileExtension = 'wav';
        }

        const fullFilename = `${filename}.${fileExtension}`;
        downloadArrayBuffer(exportedBuffer, fullFilename, mimeType);
        return fullFilename;
      };

      if (settings.scope === 'tracks') {
        // Export each track individually
        let exportedCount = 0;
        for (const track of tracks) {
          if (!track.audioBuffer) continue;

          const trackFilename = `${settings.filename}_${track.name.replace(/[^a-z0-9]/gi, '_')}`;
          await convertAndDownload(track.audioBuffer, trackFilename);
          exportedCount++;
        }

        addToast({
          title: 'Export Complete',
          description: `Exported ${exportedCount} track${exportedCount !== 1 ? 's' : ''}`,
          variant: 'success',
          duration: 3000,
        });
      } else if (settings.scope === 'selection') {
        // Export selected region
        const selectedTrack = tracks.find(t => t.selection);
        if (!selectedTrack || !selectedTrack.selection) {
          addToast({
            title: 'No Selection',
            description: 'No region selected for export',
            variant: 'warning',
            duration: 3000,
          });
          setIsExporting(false);
          return;
        }

        // Extract selection from all tracks and mix
        const selectionStart = selectedTrack.selection.start;
        const selectionEnd = selectedTrack.selection.end;
        const selectionDuration = selectionEnd - selectionStart;

        // Create tracks with only the selected region
        const selectedTracks = tracks.map(track => ({
          ...track,
          audioBuffer: track.audioBuffer
            ? extractBufferSegment(track.audioBuffer, selectionStart, selectionEnd)
            : null,
        }));

        const mixedBuffer = mixTracks(selectedTracks, sampleRate, selectionDuration);
        const filename = await convertAndDownload(mixedBuffer, settings.filename);

        addToast({
          title: 'Export Complete',
          description: `Exported ${filename}`,
          variant: 'success',
          duration: 3000,
        });
      } else {
        // Export entire project (mix all tracks)
        const maxDuration = getMaxTrackDuration(tracks);
        const mixedBuffer = mixTracks(tracks, sampleRate, maxDuration);
        const filename = await convertAndDownload(mixedBuffer, settings.filename);

        addToast({
          title: 'Export Complete',
          description: `Exported ${filename}`,
          variant: 'success',
          duration: 3000,
        });
      }

      setExportDialogOpen(false);
    } catch (error) {
      console.error('Export failed:', error);
      addToast({
        title: 'Export Failed',
        description: 'Failed to export audio',
        variant: 'error',
        duration: 3000,
      });
    } finally {
      setIsExporting(false);
    }
  }, [tracks, addToast]);

  // Zoom controls
  const handleZoomIn = () => {
    setZoom((prev) => Math.min(20, prev + 1));
  };

  const handleZoomOut = () => {
    setZoom((prev) => Math.max(1, prev - 1));
  };

  const handleFitToView = () => {
    setZoom(1);
  };

  // Keyboard shortcuts
  React.useEffect(() => {
    const handleKeyDown = (e: KeyboardEvent) => {
      // Spacebar for play/pause - only if not interacting with form elements
      if (e.code === 'Space') {
        const target = e.target as HTMLElement;
        // Don't trigger if user is typing or interacting with buttons/form elements
        if (
          target instanceof HTMLInputElement ||
          target instanceof HTMLTextAreaElement ||
          target instanceof HTMLButtonElement ||
          target.getAttribute('role') === 'button'
        ) {
          return;
        }
        e.preventDefault();
        togglePlayPause();
      }
    };

    window.addEventListener('keydown', handleKeyDown);
    return () => window.removeEventListener('keydown', handleKeyDown);
  }, [togglePlayPause]);

  // Find selected track
  const selectedTrack = tracks.find((t) => t.id === selectedTrackId);

  // Command palette actions
  const commandActions: CommandAction[] = React.useMemo(() => {
    const actions: CommandAction[] = [
      // Playback
      {
        id: 'play',
        label: 'Play',
        description: 'Start playback',
        shortcut: 'Space',
        category: 'playback',
        action: play,
      },
      {
        id: 'pause',
        label: 'Pause',
        description: 'Pause playback',
        shortcut: 'Space',
        category: 'playback',
        action: pause,
      },
      {
        id: 'stop',
        label: 'Stop',
        description: 'Stop playback',
        category: 'playback',
        action: stop,
      },
      // View
      {
        id: 'zoom-in',
        label: 'Zoom In',
        description: 'Zoom in on waveforms',
        category: 'view',
        action: handleZoomIn,
      },
      {
        id: 'zoom-out',
        label: 'Zoom Out',
        description: 'Zoom out on waveforms',
        category: 'view',
        action: handleZoomOut,
      },
      {
        id: 'fit-to-view',
        label: 'Fit to View',
        description: 'Reset zoom to fit all tracks',
        category: 'view',
        action: handleFitToView,
      },
      // Tracks
      {
        id: 'add-track',
        label: 'Add Empty Track',
        description: 'Create a new empty track',
        category: 'tracks',
        action: () => addTrack(),
      },
      {
        id: 'import-tracks',
        label: 'Import Audio Files',
        description: 'Import multiple audio files as tracks',
        category: 'tracks',
        action: handleImportTracks,
      },
      {
        id: 'clear-tracks',
        label: 'Clear All Tracks',
        description: 'Remove all tracks',
        category: 'tracks',
        action: handleClearTracks,
      },
    ];
    return actions;
  }, [play, pause, stop, handleZoomIn, handleZoomOut, handleFitToView, handleImportTracks, handleClearTracks, addTrack]);

  // Keyboard shortcuts
  React.useEffect(() => {
    const handleKeyDown = (e: KeyboardEvent) => {
      // Prevent shortcuts if typing in an input
      const isTyping = e.target instanceof HTMLInputElement || e.target instanceof HTMLTextAreaElement;

      // Spacebar: Play/Pause (always, unless typing in an input)
      if (e.code === 'Space' && !isTyping) {
        e.preventDefault();
        togglePlayPause();
        return;
      }

      if (isTyping) return;

      // Ctrl/Cmd+Z: Undo
      if ((e.ctrlKey || e.metaKey) && e.key === 'z' && !e.shiftKey) {
        e.preventDefault();
        if (canUndo) {
          undo();
        }
        return;
      }

      // Ctrl/Cmd+Shift+Z or Ctrl/Cmd+Y: Redo
      if (((e.ctrlKey || e.metaKey) && e.key === 'z' && e.shiftKey) || ((e.ctrlKey || e.metaKey) && e.key === 'y')) {
        e.preventDefault();
        if (canRedo) {
          redo();
        }
        return;
      }

      // Ctrl/Cmd+X: Cut
      if ((e.ctrlKey || e.metaKey) && e.key === 'x') {
        e.preventDefault();
        handleCut();
        return;
      }

      // Ctrl/Cmd+C: Copy
      if ((e.ctrlKey || e.metaKey) && e.key === 'c') {
        e.preventDefault();
        handleCopy();
        return;
      }

      // Ctrl/Cmd+V: Paste
      if ((e.ctrlKey || e.metaKey) && e.key === 'v') {
        e.preventDefault();
        handlePaste();
        return;
      }

      // Ctrl/Cmd+D: Duplicate
      if ((e.ctrlKey || e.metaKey) && e.key === 'd') {
        e.preventDefault();
        handleDuplicate();
        return;
      }

      // Delete or Backspace: Delete selection
      if (e.key === 'Delete' || e.key === 'Backspace') {
        e.preventDefault();
        handleDelete();
        return;
      }

      // Escape: Clear selection
      if (e.key === 'Escape') {
        e.preventDefault();
        setSelectedTrackId(null);
      }
    };

    window.addEventListener('keydown', handleKeyDown);
    return () => window.removeEventListener('keydown', handleKeyDown);
  }, [togglePlayPause, canUndo, canRedo, undo, redo, handleCut, handleCopy, handlePaste, handleDelete, handleDuplicate]);

  return (
    <>
      {/* Compact Header */}
      <header className="flex items-center justify-between px-4 py-2 border-b border-border bg-card flex-shrink-0 gap-4">
        {/* Left: Logo */}
        <div className="flex items-center gap-4 flex-shrink-0">
          <div className="flex items-center gap-2">
            <Music className="h-5 w-5 text-primary" />
            <h1 className="text-lg font-bold text-foreground">Audio UI</h1>
          </div>

          {/* Track Actions */}
          <div className="flex items-center gap-2 border-l border-border pl-4">
            <Button variant="outline" size="sm" onClick={() => addTrack()}>
              <Plus className="h-4 w-4 mr-1.5" />
              Add Track
            </Button>
            <Button variant="outline" size="sm" onClick={handleImportTracks}>
              <Upload className="h-4 w-4 mr-1.5" />
              Import
            </Button>
            {tracks.length > 0 && (
              <>
                <Button variant="outline" size="sm" onClick={() => setExportDialogOpen(true)}>
                  <Download className="h-4 w-4 mr-1.5" />
                  Export
                </Button>
                <Button variant="outline" size="sm" onClick={handleClearTracks}>
                  <Trash2 className="h-4 w-4 mr-1.5 text-destructive" />
                  Clear All
                </Button>
              </>
            )}
          </div>
        </div>

        {/* Right: Command Palette + Settings + Theme Toggle */}
        <div className="flex items-center gap-2 flex-shrink-0">
          <CommandPalette actions={commandActions} />
          <Button
            variant="ghost"
            size="icon"
            onClick={() => setSettingsDialogOpen(true)}
            title="Settings"
          >
            <Settings className="h-5 w-5" />
          </Button>
          <ThemeToggle />
        </div>
      </header>

      {/* Main content area */}
      <div className="flex flex-1 overflow-hidden">
        {/* Main canvas area */}
        <main className="flex-1 flex flex-col overflow-hidden bg-background">
          {/* Multi-Track View */}
          <div className="flex-1 flex flex-col overflow-hidden">
            <TrackList
              tracks={tracks}
              zoom={zoom}
              currentTime={currentTime}
              duration={duration}
              selectedTrackId={selectedTrackId}
              onSelectTrack={setSelectedTrackId}
              onAddTrack={addTrack}
              onImportTrack={handleImportTrack}
              onRemoveTrack={handleRemoveTrack}
              onUpdateTrack={updateTrack}
              onSeek={seek}
              onSelectionChange={handleSelectionChange}
              onToggleRecordEnable={handleToggleRecordEnable}
              recordingTrackId={recordingTrackId}
              recordingLevel={recordingState.inputLevel}
              trackLevels={trackLevels}
              onParameterTouched={setParameterTouched}
              isPlaying={isPlaying}
            />
          </div>
        </main>

        {/* Right Sidebar - Master Controls & Analyzers */}
        <aside className="flex-shrink-0 border-l border-border bg-card flex flex-col p-4 gap-4 w-[280px]">
          {/* Master Controls */}
          <div className="flex items-center justify-center">
            <MasterControls
              volume={masterVolume}
              pan={masterPan}
              peakLevel={masterPeakLevel}
              rmsLevel={masterRmsLevel}
              isClipping={masterIsClipping}
              isMuted={isMasterMuted}
              onVolumeChange={setMasterVolume}
              onPanChange={setMasterPan}
              onMuteToggle={() => {
                if (isMasterMuted) {
                  setMasterVolume(0.8);
                  setIsMasterMuted(false);
                } else {
                  setMasterVolume(0);
                  setIsMasterMuted(true);
                }
              }}
              onResetClip={resetClipIndicator}
            />
          </div>

          {/* Analyzer Toggle */}
          <div className="grid grid-cols-5 gap-0.5 bg-muted/20 border border-border/50 rounded-md p-0.5 max-w-[192px] mx-auto">
            <button
              onClick={() => setAnalyzerView('frequency')}
              className={`px-1 py-1 rounded text-[9px] font-bold uppercase tracking-wider transition-all ${
                analyzerView === 'frequency'
                  ? 'bg-accent text-accent-foreground shadow-sm'
                  : 'text-muted-foreground hover:text-foreground'
              }`}
              title="Frequency Analyzer"
            >
              FFT
            </button>
            <button
              onClick={() => setAnalyzerView('spectrogram')}
              className={`px-1 py-1 rounded text-[9px] font-bold uppercase tracking-wider transition-all ${
                analyzerView === 'spectrogram'
                  ? 'bg-accent text-accent-foreground shadow-sm'
                  : 'text-muted-foreground hover:text-foreground'
              }`}
              title="Spectrogram"
            >
              SPEC
            </button>
            <button
              onClick={() => setAnalyzerView('phase')}
              className={`px-1 py-1 rounded text-[9px] font-bold uppercase tracking-wider transition-all ${
                analyzerView === 'phase'
                  ? 'bg-accent text-accent-foreground shadow-sm'
                  : 'text-muted-foreground hover:text-foreground'
              }`}
              title="Phase Correlation"
            >
              PHS
            </button>
            <button
              onClick={() => setAnalyzerView('lufs')}
              className={`px-1 py-1 rounded text-[9px] font-bold uppercase tracking-wider transition-all ${
                analyzerView === 'lufs'
                  ? 'bg-accent text-accent-foreground shadow-sm'
                  : 'text-muted-foreground hover:text-foreground'
              }`}
              title="LUFS Loudness"
            >
              LUFS
            </button>
            <button
              onClick={() => setAnalyzerView('stats')}
              className={`px-1 py-1 rounded text-[9px] font-bold uppercase tracking-wider transition-all ${
                analyzerView === 'stats'
                  ? 'bg-accent text-accent-foreground shadow-sm'
                  : 'text-muted-foreground hover:text-foreground'
              }`}
              title="Audio Statistics"
            >
              INFO
            </button>
          </div>

          {/* Analyzer Display */}
          <div className="flex-1 min-h-[360px] flex items-start justify-center">
            <div className="w-[192px]">
              {analyzerView === 'frequency' && <FrequencyAnalyzer analyserNode={masterAnalyser} />}
              {analyzerView === 'spectrogram' && <Spectrogram analyserNode={masterAnalyser} />}
              {analyzerView === 'phase' && <PhaseCorrelationMeter analyserNode={masterAnalyser} />}
              {analyzerView === 'lufs' && <LUFSMeter analyserNode={masterAnalyser} />}
              {analyzerView === 'stats' && <AudioStatistics tracks={tracks} />}
            </div>
          </div>
        </aside>
      </div>

      {/* Transport Controls */}
      <div className="border-t border-border bg-card p-3 flex justify-center">
        <PlaybackControls
          isPlaying={isPlaying}
          isPaused={!isPlaying}
          currentTime={currentTime}
          duration={duration}
          volume={masterVolume}
          onPlay={play}
          onPause={pause}
          onStop={stop}
          onSeek={seek}
          onVolumeChange={setMasterVolume}
          currentTimeFormatted={formatDuration(currentTime)}
          durationFormatted={formatDuration(duration)}
          isRecording={recordingState.isRecording}
          onStartRecording={handleStartRecording}
          onStopRecording={handleStopRecording}
          punchInEnabled={punchInEnabled}
          punchInTime={punchInTime}
          punchOutTime={punchOutTime}
          onPunchInEnabledChange={setPunchInEnabled}
          onPunchInTimeChange={setPunchInTime}
          onPunchOutTimeChange={setPunchOutTime}
          overdubEnabled={overdubEnabled}
          onOverdubEnabledChange={setOverdubEnabled}
        />
      </div>

      {/* Import Track Dialog */}
      <ImportTrackDialog
        open={importDialogOpen}
        onClose={() => setImportDialogOpen(false)}
        onImportTrack={handleImportTrack}
      />

      {/* Global Settings Dialog */}
      <GlobalSettingsDialog
        open={settingsDialogOpen}
        onClose={() => setSettingsDialogOpen(false)}
        recordingSettings={recordingSettings}
        onInputGainChange={setInputGain}
        onRecordMonoChange={setRecordMono}
        onSampleRateChange={setSampleRate}
      />

      {/* Export Dialog */}
      <ExportDialog
        open={exportDialogOpen}
        onClose={() => setExportDialogOpen(false)}
        onExport={handleExport}
        isExporting={isExporting}
        hasSelection={tracks.some(t => t.selection !== null)}
      />
    </>
  );
}