src/App.js

import { useState, useRef, useCallback } from "react";

// ─────────────────────────────────────────────────────────
// THEME DEFINITIONS
// ─────────────────────────────────────────────────────────
const THEMES = {
  dark: {
    name: "dark",
    bg:             "#070d14",
    surface:        "#0f1923",
    surfaceAlt:     "#0a1520",
    border:         "#1e2d3d",
    borderFocus:    "#3b82f6",
    text:           "#e2e8f0",
    textMuted:      "#4a6080",
    textSub:        "#94a3b8",
    textBody:       "#cbd5e1",
    inputBg:        "#0a1520",
    uploadBg:       "#0a1520",
    uploadHover:    "#1e2d3d",
    scrollTrack:    "#0f1923",
    scrollThumb:    "#1e3a5f",
    infoBg:         "#0a1520",
    emptyColor:     "#1e3a5f",
    cardBg:         "#0f1923",
    barTrack:       "#1e2d3d",
    btnDisabled:    "#1e2d3d",
    btnDisabledTxt: "#4a6080",
    headerShadow:   "none",
    cardShadow:     "none",
  },
  light: {
    name: "light",
    bg:             "#f0f4f8",
    surface:        "#ffffff",
    surfaceAlt:     "#f8fafc",
    border:         "#d1dde9",
    borderFocus:    "#2563eb",
    text:           "#0f172a",
    textMuted:      "#64748b",
    textSub:        "#475569",
    textBody:       "#334155",
    inputBg:        "#ffffff",
    uploadBg:       "#f8fafc",
    uploadHover:    "#e2eaf4",
    scrollTrack:    "#e2e8f0",
    scrollThumb:    "#94a3b8",
    infoBg:         "#f1f5f9",
    emptyColor:     "#94a3b8",
    cardBg:         "#ffffff",
    barTrack:       "#e2e8f0",
    btnDisabled:    "#e2e8f0",
    btnDisabledTxt: "#94a3b8",
    headerShadow:   "0 1px 6px rgba(0,0,0,0.07)",
    cardShadow:     "0 1px 4px rgba(0,0,0,0.06)",
  },
};

// ─────────────────────────────────────────────────────────
// THEME TOGGLE
// ─────────────────────────────────────────────────────────
const ThemeToggle = ({ theme, onToggle }) => {
  const isDark = theme.name === "dark";
  return (
    <button onClick={onToggle} title={`Switch to ${isDark ? "light" : "dark"} mode`}
      style={{
        display: "flex", alignItems: "center", gap: 9,
        background: isDark ? "#1a2d42" : "#e8f0fa",
        border: `1px solid ${isDark ? "#2d4a6a" : "#c4d4e8"}`,
        borderRadius: 24, padding: "6px 14px 6px 8px",
        cursor: "pointer", color: theme.text,
        fontSize: 12, fontWeight: 600, letterSpacing: 0.4,
        transition: "background .3s, border-color .3s",
      }}>
      <div style={{
        width: 42, height: 23, borderRadius: 12,
        background: isDark ? "#1d4ed8" : "#f59e0b",
        position: "relative", flexShrink: 0,
        transition: "background .35s ease",
      }}>
        <div style={{
          position: "absolute", top: "50%", transform: "translateY(-50%)",
          left: isDark ? 22 : 3, width: 17, height: 17, borderRadius: "50%",
          background: "#fff", boxShadow: "0 1px 5px rgba(0,0,0,0.25)",
          display: "grid", placeItems: "center", fontSize: 9,
          transition: "left .28s ease",
        }}>{isDark ? "🌙" : "☀️"}</div>
      </div>
      <span style={{ color: theme.textMuted, userSelect: "none" }}>
        {isDark ? "Dark" : "Light"}
      </span>
    </button>
  );
};

// ─────────────────────────────────────────────────────────
// HF JUDGE SCORE BADGE  (replaces ROUGE-L badge)
// ─────────────────────────────────────────────────────────
const HFJudgeBadge = ({ score }) => {
  const pct   = parseFloat(score) * 100;
  const color = pct >= 60 ? "#22c55e" : pct >= 35 ? "#f59e0b" : "#ef4444";
  return (
    <span style={{
      background: color + "22", color,
      border: `1px solid ${color}55`,
      borderRadius: 6, padding: "2px 10px",
      fontFamily: "monospace", fontWeight: 700, fontSize: 13,
    }}>HF Judge: {pct.toFixed(1)}%</span>
  );
};

// ─────────────────────────────────────────────────────────
// OUTPUT CARD
// ─────────────────────────────────────────────────────────
const OutputCard = ({ title, icon, content, badge, accent, loading, theme }) => (
  <div style={{
    background: theme.cardBg, border: `1px solid ${accent}33`,
    borderRadius: 14, padding: 20, position: "relative", overflow: "hidden",
    boxShadow: theme.cardShadow, transition: "background .3s, box-shadow .3s",
  }}>
    <div style={{ position: "absolute", top: 0, left: 0, right: 0, height: 3, background: accent }} />
    <div style={{ display: "flex", alignItems: "center", gap: 8, marginBottom: 12 }}>
      <span style={{ fontSize: 18 }}>{icon}</span>
      <span style={{
        fontFamily: "'Courier New', monospace",
        fontSize: 11, fontWeight: 700, color: accent,
        textTransform: "uppercase", letterSpacing: 2,
      }}>{title}</span>
      {badge && <div style={{ marginLeft: "auto" }}>{badge}</div>}
    </div>
    {loading ? (
      <div style={{ display: "flex", gap: 6, alignItems: "center", color: theme.textMuted, fontSize: 13 }}>
        {[0, 0.2, 0.4].map((d, i) => (
          <span key={i} style={{ animation: `pulse 1s infinite ${d}s` }}>●</span>
        ))}
        <span style={{ marginLeft: 8 }}>Generating…</span>
      </div>
    ) : content ? (
      <p style={{ margin: 0, fontSize: 14, lineHeight: 1.78, color: theme.textBody, fontFamily: "Georgia, serif" }}>
        {content}
      </p>
    ) : (
      <p style={{ margin: 0, fontSize: 13, color: theme.textMuted, fontStyle: "italic" }}>
        Awaiting input…
      </p>
    )}
  </div>
);

// ─────────────────────────────────────────────────────────
// REWARD BREAKDOWN CARD  — mirrors inference.py output exactly
// ─────────────────────────────────────────────────────────
const RewardBar = ({ label, score, color, desc, theme }) => {
  const pct = Math.round(parseFloat(score) * 100);
  return (
    <div style={{ marginBottom: 10 }}>
      <div style={{ display: "flex", justifyContent: "space-between", marginBottom: 3 }}>
        <span style={{ fontSize: 12, color: theme.textSub, fontWeight: 600 }}>{label}</span>
        <span style={{ fontSize: 12, fontFamily: "monospace", color, fontWeight: 700 }}>
          {parseFloat(score).toFixed(4)}
        </span>
      </div>
      <div style={{ height: 8, background: theme.barTrack, borderRadius: 4 }}>
        <div style={{
          width: `${pct}%`, height: 8, borderRadius: 4,
          background: color, transition: "width 1s ease",
        }} />
      </div>
      <div style={{ fontSize: 11, color: theme.textMuted, marginTop: 2 }}>{desc}</div>
    </div>
  );
};

const RewardBreakdownCard = ({ breakdown, label, accent, theme }) => {
  if (!breakdown) return null;
  const totalPct = Math.round(parseFloat(breakdown.total) * 100);
  const totalColor = totalPct >= 60 ? "#22c55e" : totalPct >= 40 ? "#f59e0b" : "#ef4444";

  return (
    <div style={{
      background: theme.cardBg, border: `1px solid ${accent}33`,
      borderRadius: 14, padding: 20, position: "relative", overflow: "hidden",
      boxShadow: theme.cardShadow, transition: "background .3s",
      animation: "fadeIn .4s ease",
    }}>
      <div style={{ position: "absolute", top: 0, left: 0, right: 0, height: 3, background: accent }} />

      {/* Header */}
      <div style={{ display: "flex", alignItems: "center", justifyContent: "space-between", marginBottom: 16 }}>
        <div style={{ display: "flex", alignItems: "center", gap: 8 }}>
          <span style={{ fontSize: 18 }}>📊</span>
          <span style={{
            fontFamily: "'Courier New', monospace", fontSize: 11,
            fontWeight: 700, color: accent, textTransform: "uppercase", letterSpacing: 2,
          }}>
            {label} Reward Breakdown
          </span>
        </div>
        {/* Total score pill */}
        <span style={{
          background: totalColor + "22", color: totalColor,
          border: `1px solid ${totalColor}55`,
          borderRadius: 6, padding: "3px 12px",
          fontFamily: "monospace", fontWeight: 700, fontSize: 14,
        }}>
          TOTAL: {parseFloat(breakdown.total).toFixed(4)}
        </span>
      </div>

      {/* Component bars */}
      <RewardBar label="Contrastive"      score={breakdown.contrastive}     color="#3498db" desc="Beats BM25 retrieval baseline"     theme={theme} />
      <RewardBar label="ROUGE-L"          score={breakdown.rouge_l}         color="#9b59b6" desc="Surface overlap with reference"    theme={theme} />
      <RewardBar label="Negation Safety"  score={breakdown.negation_safety} color="#e67e22" desc="No hallucinated negations"         theme={theme} />
      <RewardBar label="HF Judge"         score={breakdown.hf_judge}        color="#1abc9c" desc={`BiomedBERT sim (${parseFloat(breakdown.biomed_sim).toFixed(3)}) + NLI quality (${parseFloat(breakdown.nli_quality).toFixed(3)})`} theme={theme} />

      {/* Total bar */}
      <div style={{ borderTop: `1px solid ${theme.border}`, paddingTop: 10, marginTop: 6 }}>
        <div style={{ display: "flex", justifyContent: "space-between", marginBottom: 3 }}>
          <span style={{ fontSize: 12, color: theme.text, fontWeight: 700 }}>TOTAL</span>
          <span style={{ fontSize: 13, fontFamily: "monospace", color: totalColor, fontWeight: 700 }}>
            {parseFloat(breakdown.total).toFixed(4)} / 1.0
          </span>
        </div>
        <div style={{ height: 10, background: theme.barTrack, borderRadius: 5 }}>
          <div style={{
            width: `${totalPct}%`, height: 10, borderRadius: 5,
            background: totalColor, transition: "width 1.2s ease",
          }} />
        </div>
        <div style={{ fontSize: 11, color: theme.textMuted, marginTop: 2 }}>
          Weighted average (0.25 × each component)
        </div>
      </div>
    </div>
  );
};

// ─────────────────────────────────────────────────────────
// MAIN APP
// ─────────────────────────────────────────────────────────
export default function App() {
  const [themeName, setThemeName] = useState("dark");
  const theme = THEMES[themeName];
  const toggleTheme = () => setThemeName(t => t === "dark" ? "light" : "dark");

  const [image,         setImage]         = useState(null);
  const [imageFile,     setImageFile]     = useState(null);
  const [groundTruth,   setGroundTruth]   = useState("");
  const [sftOutput,     setSftOutput]     = useState("");
  const [rewardOutput,  setRewardOutput]  = useState("");
  const [grpoOutput,    setGrpoOutput]    = useState("");
  const [rewardScore,   setRewardScore]   = useState(null);
  // ── NEW: HF Judge scores from server (replaces client-side ROUGE-L) ──
  const [sftHFJudge,    setSftHFJudge]    = useState(null);
  const [grpoHFJudge,   setGrpoHFJudge]  = useState(null);
  const [loading,       setLoading]       = useState(false);
  const [dragging,      setDragging]      = useState(false);
  const fileRef = useRef();

  // ── Pipeline ─────────────────────────────────────────
  const runInference = async () => {
    if (!image || !imageFile) return;
    setLoading(true);
    setSftOutput(""); setRewardOutput(""); setGrpoOutput("");
    setRewardScore(null);
    // ── Reset HF Judge scores ──
    setSftHFJudge(null);
    setGrpoHFJudge(null);
    const BASE = "";

    try {
      // 1. SFT
      const sftForm = new FormData();
      sftForm.append("file", imageFile);
      const sftRes  = await fetch(`${BASE}/sft`, { method: "POST", body: sftForm });
      const sftData = await sftRes.json();
      setSftOutput(sftData.report);

      // 2. Reward — send ground truth for full breakdown + hf_judge
      const rmForm = new FormData();
      rmForm.append("file", imageFile);
      rmForm.append("ground_truth", groundTruth);
      const rmRes  = await fetch(`${BASE}/reward`, { method: "POST", body: rmForm });
      const rmData = await rmRes.json();
      setRewardOutput(rmData.feedback);
      setRewardScore(parseFloat(rmData.score).toFixed(2));
      // ── Capture SFT HF Judge score from server ──
      if (rmData.hf_judge !== null && rmData.hf_judge !== undefined) {
        setSftHFJudge(rmData.hf_judge);
      }

      // 3. GRPO + its reward breakdown + hf_judge
      const grpoForm = new FormData();
      grpoForm.append("file", imageFile);
      grpoForm.append("ground_truth", groundTruth);
      const grpoRes  = await fetch(`${BASE}/grpo_reward`, { method: "POST", body: grpoForm });
      const grpoData = await grpoRes.json();
      setGrpoOutput(grpoData.report);
      // ── Capture GRPO HF Judge score from server ──
      if (grpoData.hf_judge !== null && grpoData.hf_judge !== undefined) {
        setGrpoHFJudge(grpoData.hf_judge);
      }

    } catch (err) {
      console.error("Inference error:", err);
      setSftOutput("⚠️ Could not connect to server. Please check your connection.");
    }

    setLoading(false);
  };

  // ── File handling ─────────────────────────────────────
  const handleFile = (file) => {
    if (!file || !file.type.startsWith("image/")) return;
    setImageFile(file);
    const reader = new FileReader();
    reader.onload = e => setImage(e.target.result);
    reader.readAsDataURL(file);
  };

  const onDrop = useCallback((e) => {
    e.preventDefault(); setDragging(false);
    handleFile(e.dataTransfer.files[0]);
  }, []); // eslint-disable-line

  const clearAll = () => {
    setImage(null); setImageFile(null);
    setSftOutput(""); setRewardOutput(""); setGrpoOutput("");
    setRewardScore(null);
    setSftHFJudge(null);
    setGrpoHFJudge(null);
    if (fileRef.current) fileRef.current.value = "";
  };

  return (
    <div style={{
      minHeight: "100vh", background: theme.bg, color: theme.text,
      fontFamily: "system-ui, -apple-system, sans-serif",
      transition: "background .3s ease, color .3s ease",
    }}>
      <style>{`
        @keyframes pulse  { 0%,100%{opacity:.3} 50%{opacity:1} }
        @keyframes fadeIn { from{opacity:0;transform:translateY(8px)} to{opacity:1;transform:translateY(0)} }
        * { box-sizing: border-box; margin: 0; padding: 0; }
        ::-webkit-scrollbar { width: 6px; }
        ::-webkit-scrollbar-track { background: ${theme.scrollTrack}; }
        ::-webkit-scrollbar-thumb { background: ${theme.scrollThumb}; border-radius: 3px; }
        textarea { font-family: system-ui, sans-serif; }
        textarea:focus {
          outline: none;
          border-color: ${theme.borderFocus} !important;
          box-shadow: 0 0 0 3px ${theme.borderFocus}22;
        }
        button { transition: all .22s ease !important; }
        button:not(:disabled):hover  { filter: brightness(1.1); transform: translateY(-1px); }
        button:not(:disabled):active { transform: translateY(0px); filter: brightness(0.97); }
      `}</style>

      {/* ═══ HEADER ═══ */}
      <header style={{
        borderBottom: `2px solid ${theme.border}`, padding: "20px 32px",
        display: "flex", alignItems: "center", gap: 18,
        background: `linear-gradient(135deg, ${theme.surface} 0%, ${theme.surfaceAlt} 100%)`,
        boxShadow: "0 4px 20px rgba(0,0,0,0.1)",
        transition: "background .3s, border-color .3s, box-shadow .3s",
        position: "sticky", top: 0, zIndex: 100,
        backdropFilter: "blur(10px)", WebkitBackdropFilter: "blur(10px)",
      }}>
        <div style={{
          width: 52, height: 52, flexShrink: 0,
          background: "linear-gradient(135deg,#3b82f6,#06b6d4)",
          borderRadius: 14, display: "grid", placeItems: "center",
          fontSize: 24, boxShadow: "0 4px 16px rgba(59,130,246,0.4)",
          border: "2px solid rgba(255,255,255,0.2)",
        }}>🫁</div>
        <div>
          <div style={{
            fontWeight: 900, fontSize: 22, letterSpacing: -0.8, color: theme.text,
            textShadow: theme.name === "dark" ? "0 1px 2px rgba(0,0,0,0.3)" : "none",
            marginBottom: 4,
          }}>BioStack</div>
          <div style={{
            fontSize: 12, color: theme.textMuted, letterSpacing: 1.2,
            textTransform: "uppercase", fontWeight: 600, opacity: 0.9,
          }}>NeMo Gym Based Medical Report Generation</div>
        </div>
        <div style={{ flex: 1 }} />
        <ThemeToggle theme={theme} onToggle={toggleTheme} />
      </header>

      {/* ═══ MAIN GRID ═══ */}
      <div style={{
        display: "grid", gridTemplateColumns: "370px 1fr",
        height: "calc(100vh - 155px)", overflow: "hidden",
      }}>

        {/* ══ LEFT PANEL ══ */}
        <aside style={{
          borderRight: `1px solid ${theme.border}`, padding: "15px 18px",
          display: "flex", flexDirection: "column", gap: 14,
          background: theme.surface, overflowY: "auto",
          transition: "background .3s, border-color .3s", height: "100%",
        }}>
          <div style={{ fontSize: 10, color: theme.textMuted, textTransform: "uppercase", letterSpacing: 2, fontWeight: 700 }}>
            📤 Input
          </div>

          {/* Upload zone */}
          <div>
            <label style={{
              fontSize: 11, color: theme.textMuted, textTransform: "uppercase",
              letterSpacing: 1.5, fontWeight: 700, display: "block", marginBottom: 8,
            }}>Chest X-Ray Image</label>
            <div
              onClick={() => fileRef.current.click()}
              onDragOver={e => { e.preventDefault(); setDragging(true); }}
              onDragLeave={() => setDragging(false)}
              onDrop={onDrop}
              style={{
                border: `2px dashed ${dragging ? "#3b82f6" : image ? "#22c55e66" : theme.border}`,
                borderRadius: 14, minHeight: 190,
                display: "flex", flexDirection: "column",
                alignItems: "center", justifyContent: "center",
                cursor: "pointer",
                background: dragging ? theme.uploadHover : theme.uploadBg,
                transition: "all .22s", overflow: "hidden",
              }}
            >
              {image ? (
                <img src={image} alt="X-Ray" style={{
                  width: "100%", height: "100%",
                  objectFit: "contain", maxHeight: 240, borderRadius: 12,
                }} />
              ) : (
                <>
                  <div style={{ fontSize: 40, marginBottom: 10, opacity: 0.65 }}>🩻</div>
                  <div style={{ fontSize: 13, color: theme.textMuted, textAlign: "center", lineHeight: 1.65 }}>
                    Click or drag &amp; drop<br />
                    <span style={{ fontSize: 11, color: theme.emptyColor }}>PNG, JPG, DICOM supported</span>
                  </div>
                </>
              )}
            </div>
            <input ref={fileRef} type="file" accept="image/*" style={{ display: "none" }}
              onChange={e => handleFile(e.target.files[0])} />
          </div>

          {image && (
            <button onClick={clearAll} style={{
              background: "transparent", border: `1px solid ${theme.border}`,
              color: theme.textMuted, borderRadius: 8, padding: "5px 14px",
              cursor: "pointer", fontSize: 12, alignSelf: "flex-start",
            }}>✕ Clear Image</button>
          )}


          {/* Ground truth */}
          <div>
            <label style={{
              fontSize: 11, color: theme.textMuted, textTransform: "uppercase",
              letterSpacing: 1.5, fontWeight: 700, display: "block", marginBottom: 8,
            }}>
              📋 Ground Truth{" "}
              <span style={{ color: theme.emptyColor, textTransform: "none", letterSpacing: 0, fontWeight: 400, fontSize: 11 }}>
              </span>
            </label>
            <textarea
              value={groundTruth}
              onChange={e => setGroundTruth(e.target.value)}
              placeholder="Paste the radiologist ground truth report here"
              rows={5}
              style={{
                width: "100%", background: theme.inputBg,
                border: `1px solid ${theme.border}`, borderRadius: 10,
                color: theme.text, padding: "10px 12px",
                fontSize: 13, resize: "vertical", lineHeight: 1.65,
                transition: "border .2s, box-shadow .2s, background .3s, color .3s",
              }}
            />
            {groundTruth && (
              <div style={{
                marginTop: 6, fontSize: 11, color: "#22c55e",
                display: "flex", alignItems: "center", gap: 4,
              }}>
                ✓ Ground Truth Provided — HF Judge scores will be computed
              </div>
            )}
          </div>

          {/* Run button */}
          <button
            onClick={runInference}
            disabled={!image || loading}
            style={{
              background: image && !loading
                ? "linear-gradient(135deg,#1d4ed8,#0891b2)"
                : theme.btnDisabled,
              color: image && !loading ? "#fff" : theme.btnDisabledTxt,
              border: "none", borderRadius: 12, padding: "13px 20px",
              fontSize: 14, fontWeight: 700,
              cursor: image && !loading ? "pointer" : "not-allowed",
              letterSpacing: 0.5, width: "100%",
              boxShadow: image && !loading ? "0 4px 16px rgba(29,78,216,0.38)" : "none",
            }}>
            {loading ? "⏳  Running Pipeline…" : "▶  Run NeMo Gym  Pipeline"}
          </button>
        </aside>

        {/* ══ RIGHT PANEL ══ */}
        <main style={{
          padding: "18px 22px", display: "flex", flexDirection: "column", gap: 16,
          overflowY: "auto", background: theme.bg,
          transition: "background .3s", height: "100%",
        }}>
          <div style={{ fontSize: 10, color: theme.textMuted, textTransform: "uppercase", letterSpacing: 2, fontWeight: 700 }}>
            📊 Pipeline Outputs
          </div>

          {/* SFT output — badge shows HF Judge score from server */}
          <div style={{ animation: sftOutput ? "fadeIn .4s ease" : "none" }}>
            <OutputCard
              theme={theme} title="SFT Model Output" icon="🧠" accent="#3b82f6"
              content={sftOutput} loading={loading && !sftOutput}
              badge={sftHFJudge !== null && <HFJudgeBadge score={sftHFJudge} />}
            />
          </div>

          {/* Reward output card */}
          <div style={{ animation: rewardOutput ? "fadeIn .4s ease" : "none" }}>
            <OutputCard
              theme={theme} title="Reward Model Output" icon="⚖️" accent="#f59e0b"
              content={rewardOutput} loading={loading && sftOutput && !rewardOutput}
              badge={rewardScore && (
                <div style={{
                  background: "#f59e0b22", color: "#f59e0b",
                  border: "1px solid #f59e0b55",
                  borderRadius: 6, padding: "6px 10px",
                  fontFamily: "monospace", fontWeight: 700, fontSize: 12,
                  display: "flex", flexDirection: "column", gap: 2,
                }}>
                  <div>
                    Reward: {rewardScore}
                  </div>
                  <div style={{ fontSize: 11, fontWeight: 600, opacity: 0.9 }}>
                    (0.25 × contrastive + 0.25 × ROUGE-L + 0.25 × negation_safety + 0.25 × hf_judge)
                  </div>
                </div>
              )}
            />
          </div>

          {/* GRPO output — badge shows HF Judge score from server */}
          <div style={{ animation: grpoOutput ? "fadeIn .4s ease" : "none" }}>
            <OutputCard
              theme={theme} title="NeMo Gym Output" icon="🎯" accent="#22c55e"
              content={grpoOutput} loading={loading && rewardOutput && !grpoOutput}
              badge={grpoHFJudge !== null && <HFJudgeBadge score={grpoHFJudge} />}
            />
          </div>

          {/* ── HF JUDGE COMPARISON (replaces ROUGE-L comparison) ── */}
          {groundTruth && sftOutput && grpoOutput && sftHFJudge !== null && grpoHFJudge !== null && (
            <div style={{
              background: theme.surface, border: `1px solid ${theme.border}`,
              borderRadius: 14, padding: 20, animation: "fadeIn .5s ease",
              boxShadow: theme.cardShadow, transition: "background .3s, border-color .3s",
            }}>
              <div style={{ fontSize: 10, color: theme.textMuted, textTransform: "uppercase", letterSpacing: 2, fontWeight: 700, marginBottom: 6 }}>
                🤖 HF Judge Score Comparison vs Ground Truth
              </div>
              <div style={{ fontSize: 11, color: theme.textMuted, marginBottom: 16 }}>
                BiomedBERT semantic similarity + NLI quality — computed by the server reward model
              </div>
              <div style={{ display: "grid", gridTemplateColumns: "1fr 1fr", gap: 16 }}>
                {[
                  { label: "SFT (Original)", score: sftHFJudge,  color: "#3b82f6" },
                  { label: "GRPO (Final)",   score: grpoHFJudge, color: "#22c55e" },
                ].map(({ label, score, color }) => {
                  const pct = (parseFloat(score) * 100).toFixed(1);
                  const isGRPO = label.includes("GRPO");
                  const sftPct = parseFloat(sftHFJudge) * 100;
                  const grpoPct = parseFloat(grpoHFJudge) * 100;
                  const improved = isGRPO && grpoPct > sftPct;
                  const delta = (grpoPct - sftPct).toFixed(1);
                  return (
                    <div key={label} style={{
                      background: theme.surfaceAlt, borderRadius: 10, padding: 16,
                      border: `1px solid ${color}33`, transition: "background .3s",
                    }}>
                      <div style={{ fontSize: 12, color: theme.textMuted, marginBottom: 8 }}>{label}</div>
                      <div style={{ fontSize: 28, fontWeight: 800, color, fontFamily: "monospace" }}>
                        {pct}%
                      </div>
                      <div style={{ fontSize: 11, color: theme.textMuted, marginBottom: 10 }}>
                        raw: {parseFloat(score).toFixed(4)}
                      </div>
                      <div style={{ height: 5, background: theme.barTrack, borderRadius: 3 }}>
                        <div style={{
                          width: `${pct}%`, height: "100%",
                          background: color, borderRadius: 3, transition: "width 1.2s ease",
                        }} />
                      </div>
                      {improved && (
                        <div style={{ fontSize: 11, color: "#22c55e", marginTop: 7, fontWeight: 600 }}>
                          ▲ +{delta}% improvement
                        </div>
                      )}
                      {isGRPO && !improved && grpoPct < sftPct && (
                        <div style={{ fontSize: 11, color: "#f59e0b", marginTop: 7, fontWeight: 600 }}>
                          ▼ {delta}% vs SFT
                        </div>
                      )}
                    </div>
                  );
                })}
              </div>
            </div>
          )}

          {/* Ground truth reference */}
          {groundTruth && (
            <div style={{
              background: theme.surface, border: `1px solid ${theme.border}`,
              borderRadius: 14, padding: 20,
              boxShadow: theme.cardShadow, transition: "background .3s, border-color .3s",
            }}>
              <div style={{ fontSize: 10, color: theme.textMuted, textTransform: "uppercase", letterSpacing: 2, fontWeight: 700, marginBottom: 10 }}>
                📋 Ground Truth Reference
              </div>
              <p style={{ fontSize: 14, lineHeight: 1.78, color: theme.textSub, fontFamily: "Georgia, serif" }}>
                {groundTruth}
              </p>
            </div>
          )}

          {/* Empty state */}
          {!image && !loading && (
            <div style={{
              flex: 1, display: "flex", flexDirection: "column",
              alignItems: "center", justifyContent: "center",
              color: theme.emptyColor, gap: 14, paddingTop: 60,
            }}>
              <div style={{ fontSize: 64, opacity: 0.35 }}>🩻</div>
              <div style={{ fontSize: 14, fontWeight: 600, opacity: 0.45 }}>Upload a chest X-ray to begin</div>
              <div style={{ fontSize: 12, opacity: 0.3 }}>Results will appear here after running the pipeline</div>
            </div>
          )}
        </main>
      </div>

      {/* ═══ FOOTER ═══ */}
      <footer style={{
        borderTop: `2px solid ${theme.border}`, padding: "18px 32px",
        background: `linear-gradient(135deg, ${theme.surfaceAlt} 0%, ${theme.surface} 100%)`,
        textAlign: "center", fontSize: 13, color: theme.textMuted,
        fontWeight: 600, letterSpacing: 0.5,
        transition: "background .3s, border-color .3s, color .3s",
        boxShadow: "0 -2px 10px rgba(0,0,0,0.05)",
        backdropFilter: "blur(8px)", WebkitBackdropFilter: "blur(8px)",
      }}>
        <div style={{ display: "flex", alignItems: "center", justifyContent: "center", gap: 8, opacity: 0.8 }}>
          <span style={{ fontSize: 16 }}>©</span>
          <span>2026 BioStack. All rights reserved.</span>
        </div>
      </footer>
    </div>
  );
}