import { useState, useCallback } from 'react';

interface Props {
  isPlaying: boolean;
  speed: number;
  startTime: number;
  endTime: number;
  onPlay: () => void;
  onPause: () => void;
  onReset: () => void;
  onSpeedChange: (speed: number) => void;
  onRangeChange: (start: number, end: number) => void;
}

const SPEEDS = [1, 2, 4, 8, 16];

// Preset ranges relative to T0 (main strike moment)
const T0 = new Date('2026-03-01T12:01:00Z').getTime();
const HOUR = 3600_000;

const PRESETS = [
  { label: '24H', start: T0 - 12 * HOUR, end: T0 + 12 * HOUR },
  { label: '12H', start: T0 - 6 * HOUR, end: T0 + 6 * HOUR },
  { label: '6H', start: T0 - 3 * HOUR, end: T0 + 3 * HOUR },
  { label: '2H', start: T0 - HOUR, end: T0 + HOUR },
  { label: '30M', start: T0 - 15 * 60_000, end: T0 + 15 * 60_000 },
];

const KST_OFFSET = 9 * 3600_000; // KST = UTC+9

function toKSTInput(ts: number): string {
  // Format as datetime-local value in KST: YYYY-MM-DDTHH:MM
  const d = new Date(ts + KST_OFFSET);
  const pad = (n: number) => n.toString().padStart(2, '0');
  return `${d.getUTCFullYear()}-${pad(d.getUTCMonth() + 1)}-${pad(d.getUTCDate())}T${pad(d.getUTCHours())}:${pad(d.getUTCMinutes())}`;
}

function fromKSTInput(val: string): number {
  // Parse datetime-local as KST → convert to UTC
  return new Date(val + 'Z').getTime() - KST_OFFSET;
}

export function ReplayControls({
  isPlaying,
  speed,
  startTime,
  endTime,
  onPlay,
  onPause,
  onReset,
  onSpeedChange,
  onRangeChange,
}: Props) {
  const [showPicker, setShowPicker] = useState(false);
  const [customStart, setCustomStart] = useState(toKSTInput(startTime));
  const [customEnd, setCustomEnd] = useState(toKSTInput(endTime));

  const handlePreset = useCallback((preset: typeof PRESETS[number]) => {
    onRangeChange(preset.start, preset.end);
    setCustomStart(toKSTInput(preset.start));
    setCustomEnd(toKSTInput(preset.end));
  }, [onRangeChange]);

  const handleCustomApply = useCallback(() => {
    const s = fromKSTInput(customStart);
    const e = fromKSTInput(customEnd);
    if (s < e) {
      onRangeChange(s, e);
      setShowPicker(false);
    }
  }, [customStart, customEnd, onRangeChange]);

  // Find which preset is active
  const activePreset = PRESETS.find(p => p.start === startTime && p.end === endTime);

  return (
    <div className="replay-controls">
      {/* Left: transport controls */}
      <button className="ctrl-btn" onClick={onReset} title="Reset">
        <svg width="18" height="18" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2">
          <path d="M1 4v6h6" />
          <path d="M3.51 15a9 9 0 1 0 2.13-9.36L1 10" />
        </svg>
      </button>

      <button className="ctrl-btn play-btn" onClick={isPlaying ? onPause : onPlay}>
        {isPlaying ? (
          <svg width="22" height="22" viewBox="0 0 24 24" fill="currentColor">
            <rect x="6" y="4" width="4" height="16" />
            <rect x="14" y="4" width="4" height="16" />
          </svg>
        ) : (
          <svg width="22" height="22" viewBox="0 0 24 24" fill="currentColor">
            <polygon points="5,3 19,12 5,21" />
          </svg>
        )}
      </button>

      <div className="speed-controls">
        {SPEEDS.map(s => (
          <button
            key={s}
            className={`speed-btn ${speed === s ? 'active' : ''}`}
            onClick={() => onSpeedChange(s)}
          >
            {s}x
          </button>
        ))}
      </div>

      {/* Spacer */}
      <div style={{ flex: 1 }} />

      {/* Right: range presets + custom picker */}
      <div className="range-controls">
        <div className="range-presets">
          {PRESETS.map(p => (
            <button
              key={p.label}
              className={`range-btn ${activePreset === p ? 'active' : ''}`}
              onClick={() => handlePreset(p)}
            >
              {p.label}
            </button>
          ))}
          <button
            className={`range-btn custom-btn ${showPicker ? 'active' : ''}`}
            onClick={() => setShowPicker(!showPicker)}
            title="Custom range"
          >
            <svg width="14" height="14" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2">
              <rect x="3" y="4" width="18" height="18" rx="2" />
              <line x1="16" y1="2" x2="16" y2="6" />
              <line x1="8" y1="2" x2="8" y2="6" />
              <line x1="3" y1="10" x2="21" y2="10" />
            </svg>
          </button>
        </div>

        {showPicker && (
          <div className="range-picker">
            <div className="range-picker-row">
              <label>
                <span>FROM (KST)</span>
                <input
                  type="datetime-local"
                  value={customStart}
                  onChange={e => setCustomStart(e.target.value)}
                />
              </label>
              <label>
                <span>TO (KST)</span>
                <input
                  type="datetime-local"
                  value={customEnd}
                  onChange={e => setCustomEnd(e.target.value)}
                />
              </label>
              <button className="range-apply-btn" onClick={handleCustomApply}>
                APPLY
              </button>
            </div>
          </div>
        )}
      </div>
    </div>
  );
}
