import { useState, useMemo, useEffect } from 'react';
import { ChevronLeft, ChevronRight, ChevronsLeft, ChevronsRight, Cpu } from 'lucide-react';
import ResponseBlock from './ResponseBlock';
import ResponseCarousel from './ResponseCarousel';

function buildModelLookup(providers) {
  const map = {};
  for (const p of providers) {
    for (const m of p.models) {
      map[m.id] = { name: m.name, params: m.params || '' };
    }
  }
  return map;
}

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

export default function ResultsArea({ results, multipleNeon, comparisonModelOrder = [], comparisonProviders = [], showPersonaPrompt = false, showPrePromptIndicator = false }) {
  const [carouselOffset, setCarouselOffset] = useState(0);
  const screenWidth = useWindowWidth();

  const modelLookup = useMemo(() => buildModelLookup(comparisonProviders), [comparisonProviders]);

  const orderedComparisonIds = comparisonModelOrder;

  const sortComparisons = (responses) => {
    const byId = {};
    for (const r of responses) byId[r.model_id] = r;
    const ordered = [];
    for (const id of orderedComparisonIds) {
      if (byId[id]) ordered.push(byId[id]);
    }
    for (const r of responses) {
      if (!orderedComparisonIds.includes(r.model_id)) ordered.push(r);
    }
    return ordered;
  };

  const totalComparisons = orderedComparisonIds.length;
  const isMobile = screenWidth <= 480;
  const isTablet = screenWidth <= 900;
  const visible = isMobile ? 1 : (isTablet ? 1 : 2);
  const maxOffset = Math.max(0, totalComparisons - visible);

  const skipStart = () => setCarouselOffset(0);
  const prev = () => setCarouselOffset(o => Math.max(0, o - 1));
  const next = () => setCarouselOffset(o => Math.min(maxOffset, o + 1));
  const skipEnd = () => setCarouselOffset(maxOffset);

  const visibleComparisonIds = orderedComparisonIds.slice(carouselOffset, carouselOffset + visible);
  const visibleColumnHeaders = visibleComparisonIds.map(id => {
    const info = modelLookup[id];
    return info ? { name: info.name, params: info.params } : { name: id.split('/').pop(), params: '' };
  });

  if (!results.length) {
    return null;
  }

  return (
    <div className="results-area">
      {results.map((result, ri) => (
        <div key={ri} className="result-group">
          {multipleNeon ? (
            <>
              <div className="result-sticky-header">
                <div className="result-query">
                  <span className="result-query-label">Q:</span>
                  {result.query}
                </div>

                {showPersonaPrompt && result.groups.map((group, gi) => {
                  if (!group.system_prompt) return null;
                  const rawId = (group.neon_model_id || '').split('@')[0];
                  const modelName = rawId.includes('/') ? rawId.split('/').pop() : rawId;
                  const persona = group.neon_persona || '';
                  const label = `${modelName} - ${persona} pre-prompt:`;
                  return (
                    <div key={gi} className="result-query result-preprompt">
                      <span className="result-query-label">{label}</span>
                      {group.system_prompt}
                    </div>
                  );
                })}

                {totalComparisons > visible && (
                  <div className="carousel-unified-controls">
                    <button className="carousel-btn" onClick={skipStart} disabled={carouselOffset === 0} title="First">
                      <ChevronsLeft size={16} />
                    </button>
                    <button className="carousel-btn" onClick={prev} disabled={carouselOffset === 0} title="Previous">
                      <ChevronLeft size={16} />
                    </button>
                    <span className="carousel-indicator">
                      {carouselOffset + 1}–{Math.min(carouselOffset + visible, totalComparisons)} of {totalComparisons}
                    </span>
                    <button className="carousel-btn" onClick={next} disabled={carouselOffset >= maxOffset} title="Next">
                      <ChevronRight size={16} />
                    </button>
                    <button className="carousel-btn" onClick={skipEnd} disabled={carouselOffset >= maxOffset} title="Last">
                      <ChevronsRight size={16} />
                    </button>
                  </div>
                )}

                <div className="column-headers">
                  <div className="column-header neon-column-header">
                    <Cpu size={16} />
                    <span className="col-header-name">Neon.ai</span>
                    <span className="col-header-params">24B (quantized)</span>
                  </div>
                  <div className="column-headers-comparison">
                    {visibleColumnHeaders.map((col, i) => (
                      <div key={visibleComparisonIds[i]} className="column-header comparison-column-header">
                        <span className="col-header-name">{col.name}</span>
                        {col.params && <span className="col-header-params">{col.params}</span>}
                      </div>
                    ))}
                  </div>
                </div>
              </div>

              {result.groups.map((group, gi) => {
                const neonResponse = group.responses.find(r => r.is_neon);
                const comparisonResponses = sortComparisons(group.responses.filter(r => !r.is_neon));

                return (
                  <div key={gi} className="carousel-wrapper">
                    {neonResponse ? (
                      <ResponseCarousel
                        neonResponse={neonResponse}
                        comparisonResponses={comparisonResponses}
                        offset={carouselOffset}
                        showPrePromptIndicator={showPrePromptIndicator}
                      />
                    ) : (
                      <div className="result-flat-grid">
                        {comparisonResponses.map((r, ci) => (
                          <ResponseBlock key={ci} response={r} showBadge={false} isComparisonEmphasis={true} showPrePromptIndicator={showPrePromptIndicator} />
                        ))}
                        {group.responses.length === 0 && (
                          <div className="response-pending">Waiting for responses...</div>
                        )}
                      </div>
                    )}
                  </div>
                );
              })}
            </>
          ) : (
            <>
              <div className="result-query">
                <span className="result-query-label">Q:</span>
                {result.query}
              </div>
              {showPersonaPrompt && result.groups[0]?.system_prompt && (() => {
                const g = result.groups[0];
                const rawId = (g.neon_model_id || '').split('@')[0];
                const modelName = rawId.includes('/') ? rawId.split('/').pop() : rawId;
                const persona = g.neon_persona || '';
                const label = `${modelName} - ${persona} pre-prompt:`;
                return (
                  <div className="result-query result-preprompt">
                    <span className="result-query-label">{label}</span>
                    {g.system_prompt}
                  </div>
                );
              })()}
              {result.groups.map((group, gi) => {
                const neonResponse = group.responses.find(r => r.is_neon);
                const comparisonResponses = sortComparisons(group.responses.filter(r => !r.is_neon));

                return (
                  <div key={gi} className="result-flat-grid">
                    {neonResponse && (
                      <ResponseBlock
                        response={neonResponse}
                        isNeonEmphasis={true}
                        showBadge={false}
                        showModelName={true}
                        showPersona={false}
                        showPrePromptIndicator={showPrePromptIndicator}
                      />
                    )}
                    {comparisonResponses.map((r, ci) => (
                      <ResponseBlock key={ci} response={r} showBadge={false} isComparisonEmphasis={true} showPrePromptIndicator={showPrePromptIndicator} />
                    ))}
                    {group.responses.length === 0 && (
                      <div className="response-pending">Waiting for responses...</div>
                    )}
                  </div>
                );
              })}
            </>
          )}
        </div>
      ))}

      <style>{`
        .results-area {
          display: flex;
          flex-direction: column;
          gap: 28px;
        }
        .result-group {
          display: flex;
          flex-direction: column;
          gap: 14px;
        }
        .result-sticky-header {
          position: sticky;
          top: 0;
          z-index: 10;
          background: var(--bg-gradient);
          padding-bottom: 6px;
          display: flex;
          flex-direction: column;
          gap: 8px;
        }
        .result-query {
          font-size: 15px;
          font-weight: 500;
          color: var(--text-primary);
          padding: 10px 14px;
          background: var(--bg-tertiary);
          border-radius: 10px;
          border-left: 4px solid var(--query-accent);
        }
        .result-query-label {
          font-weight: 700;
          color: var(--query-accent);
          margin-right: 6px;
        }
        .result-preprompt {
          white-space: pre-wrap;
          max-height: 200px;
          overflow-y: auto;
          border-left-color: var(--neon-border);
        }
        .result-preprompt .result-query-label {
          color: var(--neon-accent);
        }
        .carousel-unified-controls {
          display: flex;
          align-items: center;
          justify-content: center;
          gap: 6px;
          padding: 4px 0;
        }
        .carousel-btn {
          display: flex;
          align-items: center;
          justify-content: center;
          width: 30px;
          height: 30px;
          border: 1px solid var(--border-primary);
          border-radius: 6px;
          background: var(--card-bg);
          color: var(--text-secondary);
          transition: all 0.15s;
        }
        .carousel-btn:hover:not(:disabled) {
          background: var(--bg-tertiary);
          border-color: var(--accent-primary);
          color: var(--accent-primary);
        }
        .carousel-btn:disabled {
          opacity: 0.3;
          cursor: not-allowed;
        }
        .carousel-indicator {
          font-size: 12px;
          color: var(--text-muted);
          white-space: nowrap;
          min-width: 80px;
          text-align: center;
          font-weight: 500;
        }

        /* Column headers */
        .column-headers {
          display: grid;
          grid-template-columns: 1fr 2fr;
          gap: 12px;
        }
        .column-header {
          padding: 8px 12px;
          border-radius: 8px;
          font-size: 15px;
          font-weight: 700;
          display: flex;
          align-items: center;
          gap: 8px;
          min-width: 0;
        }
        .neon-column-header {
          color: #111827;
          background: var(--neon-bg);
          border: 2px solid var(--neon-border);
        }
        :root[data-theme="dark"] .neon-column-header {
          color: #F9FAFB;
        }
        .column-headers-comparison {
          display: flex;
          gap: 12px;
          min-width: 0;
        }
        .comparison-column-header {
          flex: 1;
          min-width: 0;
          background: var(--comp-bg);
          border: 2px solid var(--comp-border);
          color: var(--text-primary);
        }
        .col-header-name {
          white-space: nowrap;
          overflow: hidden;
          text-overflow: ellipsis;
        }
        .col-header-params {
          font-weight: 400;
          font-size: 12px;
          color: var(--text-secondary);
          white-space: nowrap;
          margin-left: auto;
        }

        .result-flat-grid {
          display: grid;
          grid-template-columns: repeat(auto-fill, minmax(min(100%, 320px), 1fr));
          gap: 12px;
        }
        .response-pending {
          display: flex;
          align-items: center;
          justify-content: center;
          padding: 24px;
          color: var(--text-muted);
          font-size: 13px;
          font-style: italic;
          border: 1px dashed var(--border-primary);
          border-radius: 12px;
          grid-column: 1 / -1;
        }

        /* Responsive: tablet */
        @media (max-width: 900px) {
          .result-sticky-header {
            position: relative;
          }
          .column-headers {
            grid-template-columns: 1fr 1fr;
            gap: 8px;
          }
          .column-header {
            font-size: 13px;
            padding: 6px 10px;
            gap: 4px;
          }
          .col-header-params {
            font-size: 10px;
          }
          .carousel-btn {
            width: 36px;
            height: 36px;
          }
          .result-flat-grid {
            grid-template-columns: 1fr;
          }
        }

        /* Responsive: phone */
        @media (max-width: 480px) {
          .result-query {
            font-size: 13px;
            padding: 8px 10px;
          }
          .column-headers {
            grid-template-columns: 1fr;
            gap: 6px;
          }
          .column-headers-comparison {
            flex-direction: column;
            gap: 6px;
          }
          .carousel-btn {
            width: 40px;
            height: 40px;
          }
          .carousel-indicator {
            font-size: 13px;
          }
        }
      `}</style>
    </div>
  );
}