import { useState, useEffect } from 'react';
import ResponseBlock from './ResponseBlock';

function useWindowWidth() {
  const [w, setW] = useState(typeof window !== 'undefined' ? window.innerWidth : 1200);
  useEffect(() => {
    const h = () => setW(window.innerWidth);
    window.addEventListener('resize', h);
    return () => window.removeEventListener('resize', h);
  }, []);
  return w;
}

export default function ResponseCarousel({ neonResponse, comparisonResponses, offset = 0, showPrePromptIndicator = false }) {
  const screenWidth = useWindowWidth();
  const isMobile = screenWidth <= 480;
  const isTablet = screenWidth <= 900;
  const visible = isMobile ? 1 : (isTablet ? 1 : 2);
  const visibleComparisons = comparisonResponses.slice(offset, offset + visible);

  return (
    <div className={`carousel-track ${isMobile ? 'carousel-track--stacked' : ''} ${isTablet && !isMobile ? 'carousel-track--tablet' : ''}`}>
      <div className="carousel-sticky">
        <ResponseBlock
          response={neonResponse}
          isNeonEmphasis={true}
          showBadge={false}
          showModelName={true}
          showPersona={true}
          showFooterParams={false}
          showPrePromptIndicator={showPrePromptIndicator}
        />
      </div>
      <div className="carousel-scrollable">
        {visibleComparisons.map((r, i) => (
          <ResponseBlock
            key={`${r.model_id}-${offset + i}`}
            response={r}
            showBadge={false}
            showModelName={false}
            showFooterParams={false}
            isComparisonEmphasis={true}
            showPrePromptIndicator={showPrePromptIndicator}
          />
        ))}
        {comparisonResponses.length === 0 && (
          <div className="carousel-empty">No comparison models selected</div>
        )}
      </div>

      <style>{`
        .carousel-track {
          display: grid;
          grid-template-columns: 1fr 2fr;
          gap: 12px;
          align-items: stretch;
        }
        .carousel-track--tablet {
          grid-template-columns: 1fr 1fr;
        }
        .carousel-track--stacked {
          grid-template-columns: 1fr;
        }
        .carousel-sticky {
          min-width: 0;
          display: flex;
        }
        .carousel-scrollable {
          display: flex;
          gap: 12px;
          min-width: 0;
          overflow: hidden;
        }
        .carousel-scrollable .response-block {
          flex: 1;
          min-width: 0;
        }
        .carousel-empty {
          display: flex;
          align-items: center;
          justify-content: center;
          flex: 1;
          color: var(--text-muted);
          font-size: 13px;
          font-style: italic;
          border: 1px dashed var(--border-primary);
          border-radius: 12px;
          padding: 24px;
        }
      `}</style>
    </div>
  );
}