rocketry/src/components/trajectory/TimelineBar.jsx

import { useState, useRef, useEffect } from 'react'

export function TimelineBar({
  simulationResults,
  currentTime,
  onTimeChange,
  isPlaying,
  onPlayPause,
  playbackSpeed,
  onPlaybackSpeedChange,
}) {
  const [showEventForm, setShowEventForm] = useState(false)
  const [newEventTime, setNewEventTime] = useState('')
  const [newEventLabel, setNewEventLabel] = useState('')
  const [newEventType, setNewEventType] = useState('marker')
  const timelineRef = useRef(null)

  if (!simulationResults) {
    return (
      <div className="bg-slate-800 border-t border-slate-700 p-4 h-32">
        <p className="text-slate-400 text-sm">Run simulation to see timeline</p>
      </div>
    )
  }

  const { states, events, summary } = simulationResults
  const maxTime = summary.t_max

  // Handle timeline scrub
  const handleTimelineClick = (e) => {
    if (!timelineRef.current) return
    const rect = timelineRef.current.getBoundingClientRect()
    const percent = (e.clientX - rect.left) / rect.width
    const t = Math.max(0, Math.min(maxTime, percent * maxTime))
    onTimeChange(t)
  }

  // Event colors
  const eventColors = {
    engine: '#ef4444',
    guidance: '#f59e0b',
    marker: '#8b5cf6',
    jettison: '#06b6d4',
  }

  return (
    <div className="bg-slate-800 border-t border-slate-700">
      {/* Playback controls */}
      <div className="flex items-center gap-3 px-4 py-3 border-b border-slate-700">
        <button
          onClick={() => onTimeChange(0)}
          className="px-2 py-1 bg-slate-700 hover:bg-slate-600 rounded text-xs text-slate-300"
          title="Rewind"
        >
          ◀◀
        </button>

        <button
          onClick={onPlayPause}
          className={`px-3 py-1 rounded text-xs font-medium ${
            isPlaying
              ? 'bg-red-600 hover:bg-red-500 text-white'
              : 'bg-blue-600 hover:bg-blue-500 text-white'
          }`}
        >
          {isPlaying ? '⏸ Pause' : '▶ Play'}
        </button>

        <div className="flex items-center gap-1">
          <span className="text-xs text-slate-400">Speed:</span>
          <select
            value={playbackSpeed}
            onChange={e => onPlaybackSpeedChange(parseFloat(e.target.value))}
            className="px-2 py-0.5 bg-slate-700 border border-slate-600 rounded text-xs text-slate-300 focus:outline-none"
          >
            <option value={1}>1×</option>
            <option value={5}>5×</option>
            <option value={10}>10×</option>
          </select>
        </div>

        <span className="text-sm text-slate-300 font-mono ml-auto">
          t = {currentTime.toFixed(2)} s / {maxTime.toFixed(1)} s
        </span>
      </div>

      {/* Timeline */}
      <div className="relative px-4 py-4">
        <div
          ref={timelineRef}
          onClick={handleTimelineClick}
          className="relative h-12 bg-slate-900 border border-slate-700 rounded cursor-pointer hover:bg-slate-800 transition-colors"
        >
          {/* Event markers */}
          {events.map(event => {
            const percent = (event.t / maxTime) * 100
            return (
              <div
                key={event.id}
                style={{
                  left: `${percent}%`,
                  backgroundColor: event.color || eventColors[event.type] || '#64748b',
                }}
                className="absolute top-0 bottom-0 w-1 rounded-t hover:brightness-150"
                title={`${event.label} @ t=${event.t.toFixed(2)}s`}
              >
                {/* Label above */}
                <div className="absolute bottom-full mb-1 left-1/2 transform -translate-x-1/2 bg-slate-700 border border-slate-600 rounded px-2 py-1 text-xs text-white whitespace-nowrap opacity-0 hover:opacity-100 transition-opacity z-10">
                  {event.label}
                </div>
              </div>
            )
          })}

          {/* Playhead */}
          <div
            style={{ left: `${(currentTime / maxTime) * 100}%` }}
            className="absolute top-0 bottom-0 w-0.5 bg-emerald-400 pointer-events-none"
          />
        </div>

        {/* Event list below */}
        <div className="mt-3 text-xs space-y-1">
          {events.slice(0, 5).map(event => (
            <div key={event.id} className="flex items-center gap-2 text-slate-400">
              <div
                className="w-2 h-2 rounded-full"
                style={{ backgroundColor: event.color || eventColors[event.type] || '#64748b' }}
              />
              <span className="w-20 text-slate-500">{event.t.toFixed(1)}s</span>
              <span>{event.label}</span>
            </div>
          ))}
          {events.length > 5 && (
            <div className="text-slate-500">+{events.length - 5} more events</div>
          )}
        </div>
      </div>
    </div>
  )
}