audio-ui/components/tracks/Track.tsx

'use client';

import * as React from 'react';
import type { Track as TrackType } from '@/types/track';
import { TrackHeader } from './TrackHeader';
import { cn } from '@/lib/utils/cn';

export interface TrackProps {
  track: TrackType;
  zoom: number;
  currentTime: number;
  duration: number;
  isSelected?: boolean;
  onSelect?: () => void;
  onToggleMute: () => void;
  onToggleSolo: () => void;
  onToggleCollapse: () => void;
  onVolumeChange: (volume: number) => void;
  onPanChange: (pan: number) => void;
  onRemove: () => void;
  onNameChange: (name: string) => void;
  onSeek?: (time: number) => void;
}

export function Track({
  track,
  zoom,
  currentTime,
  duration,
  isSelected,
  onSelect,
  onToggleMute,
  onToggleSolo,
  onToggleCollapse,
  onVolumeChange,
  onPanChange,
  onRemove,
  onNameChange,
  onSeek,
}: TrackProps) {
  const canvasRef = React.useRef<HTMLCanvasElement>(null);
  const containerRef = React.useRef<HTMLDivElement>(null);

  // Draw waveform
  React.useEffect(() => {
    if (!track.audioBuffer || !canvasRef.current || track.collapsed) return;

    const canvas = canvasRef.current;
    const ctx = canvas.getContext('2d');
    if (!ctx) return;

    const dpr = window.devicePixelRatio || 1;
    const rect = canvas.getBoundingClientRect();

    canvas.width = rect.width * dpr;
    canvas.height = rect.height * dpr;
    ctx.scale(dpr, dpr);

    const width = rect.width;
    const height = rect.height;

    // Clear canvas
    ctx.fillStyle = 'rgb(15, 23, 42)';
    ctx.fillRect(0, 0, width, height);

    const buffer = track.audioBuffer;
    const channelData = buffer.getChannelData(0);
    const samplesPerPixel = Math.floor(buffer.length / (width * zoom));

    // Draw waveform
    ctx.fillStyle = track.color;
    ctx.strokeStyle = track.color;
    ctx.lineWidth = 1;

    for (let x = 0; x < width; x++) {
      const startSample = Math.floor(x * samplesPerPixel);
      const endSample = Math.floor((x + 1) * samplesPerPixel);

      let min = 1.0;
      let max = -1.0;

      for (let i = startSample; i < endSample && i < channelData.length; i++) {
        const sample = channelData[i];
        if (sample < min) min = sample;
        if (sample > max) max = sample;
      }

      const y1 = (height / 2) * (1 - max);
      const y2 = (height / 2) * (1 - min);

      ctx.beginPath();
      ctx.moveTo(x, y1);
      ctx.lineTo(x, y2);
      ctx.stroke();
    }

    // Draw center line
    ctx.strokeStyle = 'rgba(148, 163, 184, 0.2)';
    ctx.lineWidth = 1;
    ctx.beginPath();
    ctx.moveTo(0, height / 2);
    ctx.lineTo(width, height / 2);
    ctx.stroke();

    // Draw playhead
    if (duration > 0) {
      const playheadX = (currentTime / duration) * width;
      ctx.strokeStyle = 'rgba(59, 130, 246, 0.8)';
      ctx.lineWidth = 2;
      ctx.beginPath();
      ctx.moveTo(playheadX, 0);
      ctx.lineTo(playheadX, height);
      ctx.stroke();
    }
  }, [track.audioBuffer, track.color, track.collapsed, zoom, currentTime, duration]);

  const handleCanvasClick = (e: React.MouseEvent<HTMLCanvasElement>) => {
    if (!onSeek || !duration) return;

    const rect = e.currentTarget.getBoundingClientRect();
    const x = e.clientX - rect.left;
    const clickTime = (x / rect.width) * duration;
    onSeek(clickTime);
  };

  if (track.collapsed) {
    return (
      <div
        className={cn(
          'border-b border-border cursor-pointer',
          isSelected && 'ring-2 ring-primary ring-inset'
        )}
        onClick={onSelect}
      >
        <TrackHeader
          track={track}
          onToggleMute={onToggleMute}
          onToggleSolo={onToggleSolo}
          onToggleCollapse={onToggleCollapse}
          onVolumeChange={onVolumeChange}
          onPanChange={onPanChange}
          onRemove={onRemove}
          onNameChange={onNameChange}
        />
      </div>
    );
  }

  return (
    <div
      ref={containerRef}
      className={cn(
        'border-b border-border cursor-pointer',
        isSelected && 'ring-2 ring-primary ring-inset'
      )}
      onClick={onSelect}
    >
      <TrackHeader
        track={track}
        onToggleMute={onToggleMute}
        onToggleSolo={onToggleSolo}
        onToggleCollapse={onToggleCollapse}
        onVolumeChange={onVolumeChange}
        onPanChange={onPanChange}
        onRemove={onRemove}
        onNameChange={onNameChange}
      />
      <div className="relative" style={{ height: track.height }}>
        {track.audioBuffer ? (
          <canvas
            ref={canvasRef}
            className="w-full h-full cursor-pointer"
            onClick={handleCanvasClick}
          />
        ) : (
          <div className="flex items-center justify-center h-full text-sm text-muted-foreground">
            No audio loaded
          </div>
        )}
      </div>
    </div>
  );
}