kit-ui/components/animate/KeyframeTimeline.tsx

'use client';

import { useRef } from 'react';
import { Plus, Trash2 } from 'lucide-react';
import { cn, iconBtn } from '@/lib/utils';
import type { Keyframe } from '@/types/animate';

interface Props {
  keyframes: Keyframe[];
  selectedId: string | null;
  onSelect: (id: string) => void;
  onAdd: (offset: number) => void;
  onDelete: (id: string) => void;
  onMove: (id: string, newOffset: number) => void;
  embedded?: boolean; // when true, no glass card wrapper (use inside another card)
}

const TICKS = [25, 50, 75];

const timelineBtn = cn(iconBtn, 'w-6 h-6');

export function KeyframeTimeline({ keyframes, selectedId, onSelect, onAdd, onDelete, onMove, embedded = false }: Props) {
  const trackRef = useRef<HTMLDivElement>(null);

  const getOffsetFromEvent = (clientX: number): number => {
    if (!trackRef.current) return 0;
    const rect = trackRef.current.getBoundingClientRect();
    const pct = ((clientX - rect.left) / rect.width) * 100;
    return Math.round(Math.min(100, Math.max(0, pct)));
  };

  const handleTrackClick = (e: React.MouseEvent<HTMLDivElement>) => {
    if ((e.target as HTMLElement).closest('[data-keyframe-marker]')) return;
    onAdd(getOffsetFromEvent(e.clientX));
  };

  const handlePointerDown = (e: React.PointerEvent, id: string) => {
    e.preventDefault();
    onSelect(id);
    const el = e.currentTarget as HTMLElement;
    el.setPointerCapture(e.pointerId);
    const handleMove = (me: PointerEvent) => onMove(id, getOffsetFromEvent(me.clientX));
    const handleUp = () => {
      el.removeEventListener('pointermove', handleMove);
      el.removeEventListener('pointerup', handleUp);
    };
    el.addEventListener('pointermove', handleMove);
    el.addEventListener('pointerup', handleUp);
  };

  const sorted = [...keyframes].sort((a, b) => a.offset - b.offset);
  const selectedKf = keyframes.find((k) => k.id === selectedId);

  const content = (
    <div className="space-y-2">
      {/* Header */}
      <div className="flex items-center justify-between">
        <div className="flex items-center gap-2">
          <span className="text-[10px] font-semibold text-muted-foreground uppercase tracking-widest">
            Keyframes
          </span>
          <span className="text-[9px] text-muted-foreground/40 font-mono">
            {keyframes.length} kf{selectedKf ? ` · ${selectedKf.offset}%` : ''}
          </span>
        </div>
        <div className="flex items-center gap-1">
          <button onClick={() => onAdd(50)} title="Add at 50%" className={timelineBtn}>
            <Plus className="w-3 h-3" />
          </button>
          <button
            onClick={() => selectedId && onDelete(selectedId)}
            disabled={!selectedId || keyframes.length <= 2}
            title="Delete selected"
            className={timelineBtn}
          >
            <Trash2 className="w-3 h-3" />
          </button>
        </div>
      </div>

      {/* Track */}
      <div
        ref={trackRef}
        className="relative h-14 bg-white/3 rounded-lg border border-border/25 cursor-crosshair select-none mx-4"
        onClick={handleTrackClick}
      >
        <div className="absolute inset-x-0 top-1/2 -translate-y-1/2 h-px bg-border/30" />
        {TICKS.map((tick) => (
          <div
            key={tick}
            className="absolute top-0 bottom-0 flex flex-col items-center pointer-events-none -ml-1.5"
            style={{ left: `${tick}%` }}
          >
            <div className="w-px h-2 bg-muted-foreground/20" />
            <span className="text-[8px] text-muted-foreground/30 mt-auto mb-1 font-mono">{tick}%</span>
          </div>
        ))}
        {sorted.map((kf) => (
          <button
            key={kf.id}
            data-keyframe-marker
            className={cn(
              'absolute top-1/2 -translate-y-1/2 -translate-x-1/2 w-3.5 h-3.5 rotate-45 rounded-sm transition-all duration-150 touch-none',
              kf.id === selectedId
                ? 'bg-primary shadow-lg shadow-primary/40 scale-125'
                : 'bg-muted-foreground/40 hover:bg-primary/70'
            )}
            style={{ left: `${kf.offset}%` }}
            onClick={(e) => { e.stopPropagation(); onSelect(kf.id); }}
            onPointerDown={(e) => handlePointerDown(e, kf.id)}
            title={`${kf.offset}% — drag to move`}
          />
        ))}
      </div>

      {/* Offset labels */}
      <div className="relative h-4 mx-4">
        {sorted.map((kf) => (
          <span
            key={kf.id}
            className={cn(
              'absolute -translate-x-1/2 text-[9px] font-mono transition-colors',
              kf.id === selectedId ? 'text-primary font-medium' : 'text-muted-foreground/40'
            )}
            style={{ left: `${kf.offset}%` }}
          >
            {kf.offset}%
          </span>
        ))}
      </div>
    </div>
  );

  if (embedded) return <div>{content}</div>;

  return (
    <div className="glass rounded-xl px-4 pt-4 pb-3 shrink-0">
      {content}
    </div>
  );
}