interface SegmentedProgressBarProps {
  totalSegments: number;
  currentIndex: number;
  segmentProgress: number;
  onSeek: (ratio: number) => void;
}

export function SegmentedProgressBar({
  totalSegments,
  currentIndex,
  segmentProgress,
  onSeek,
}: SegmentedProgressBarProps) {
  const seekFromClientX = (clientX: number, element: HTMLElement) => {
    const rect = element.getBoundingClientRect();
    onSeek((clientX - rect.left) / rect.width);
  };

  return (
    <div
      className="relative h-1.5 cursor-pointer touch-none"
      onClick={(e) => {
        seekFromClientX(e.clientX, e.currentTarget as HTMLElement);
      }}
      onPointerDown={(e) => {
        if (e.pointerType === "mouse" && e.button !== 0) return;
        e.currentTarget.setPointerCapture(e.pointerId);
        seekFromClientX(e.clientX, e.currentTarget);
      }}
      onPointerMove={(e) => {
        if (!e.currentTarget.hasPointerCapture(e.pointerId)) return;
        seekFromClientX(e.clientX, e.currentTarget);
      }}
      onPointerUp={(e) => {
        if (e.currentTarget.hasPointerCapture(e.pointerId)) {
          e.currentTarget.releasePointerCapture(e.pointerId);
        }
      }}
      onPointerCancel={(e) => {
        if (e.currentTarget.hasPointerCapture(e.pointerId)) {
          e.currentTarget.releasePointerCapture(e.pointerId);
        }
      }}
    >
      <div className="flex gap-1.5 h-full">
        {Array.from({ length: totalSegments }).map((_, i) => {
          let fill = 0;
          if (i < currentIndex) fill = 1;
          else if (i === currentIndex) fill = segmentProgress;
          return (
            <div
              key={i}
              aria-label={`第 ${i + 1} 段`}
              className="relative flex-1 h-full rounded-full bg-white/25 overflow-hidden"
            >
              <div
                className="h-full origin-left bg-white"
                style={{
                  transform: `scaleX(${Math.max(0, Math.min(1, fill))})`,
                }}
              />
            </div>
          );
        })}
      </div>
    </div>
  );
}