web/src/components/risk-simulation-panel.tsx

import {
  type DriverTweak,
  distributionSupportsSpread,
  IDENTITY_TWEAK,
  isIdentityTweak,
  tweakedInputs,
  tweakSummary,
} from '@szl-holdings/monte-carlo';
import { runScenarioInPool } from '@szl-holdings/monte-carlo/scenario-pool';
import {
  type MonteCarloResult,
  runScenarioSimulation as runScenarioSimulationSync,
} from '@szl-holdings/monte-carlo/scenario-simulation';
import type { InputVariable, ScenarioDefinition } from '@szl-holdings/monte-carlo/schema';
import { DriverTweakPresets } from '@szl-holdings/shared-ui/driver-tweak-presets';
import { LANE_ACCENT_HEX } from '@szl-holdings/shared-ui/lane-colors';
import { type SavedRiskRun, SaveRiskRunButton } from '@szl-holdings/shared-ui/risk-evidence';
import { motion } from 'framer-motion';
import {
  Activity,
  BarChart3,
  BookmarkPlus,
  ChevronDown,
  ChevronUp,
  Layers,
  RefreshCw,
  RotateCcw,
  Sliders,
  X,
} from 'lucide-react';
import { useEffect, useMemo, useRef, useState } from 'react';
import RiskSimulationWorker from '@/workers/risk-simulation.worker?worker';

const VESSELS_ACCENT = LANE_ACCENT_HEX.vessels.primaryLight;

export type { MonteCarloResult };
export { runScenarioSimulationSync as runScenarioSimulation };

interface SimulationProgressState {
  completed: number;
  total: number;
}

function formatValue(value: number, format?: string): string {
  if (!Number.isFinite(value)) return '—';
  if (format === 'currency') {
    const abs = Math.abs(value);
    if (abs >= 1000) return `$${(value / 1000).toFixed(1)}K`;
    return `$${value.toFixed(2)}`;
  }
  if (format === 'percentage') return `${value.toFixed(1)}%`;
  if (format === 'years') return `${value.toFixed(1)}y`;
  return value.toLocaleString(undefined, { maximumFractionDigits: 2 });
}

function formatSignedValue(value: number, format?: string): string {
  if (!Number.isFinite(value)) return '—';
  const sign = value > 0 ? '+' : value < 0 ? '−' : '';
  return `${sign}${formatValue(Math.abs(value), format)}`;
}

function formatPctDelta(curr: number, base: number): string {
  if (!Number.isFinite(curr) || !Number.isFinite(base) || base === 0) return '—';
  const pct = ((curr - base) / Math.abs(base)) * 100;
  const sign = pct > 0 ? '+' : pct < 0 ? '−' : '';
  return `${sign}${Math.abs(pct).toFixed(1)}%`;
}

interface BaselineSnapshot {
  result: MonteCarloResult;
  capturedAt: number;
  tweakCount: number;
}

interface RiskSimulationPanelProps {
  scenario: ScenarioDefinition;
  iterations?: number;
  accentColor?: string;
  title?: string;
  subtitle?: string;
  evidenceDomain?: string;
}

export function RiskSimulationPanel({
  scenario,
  iterations = 5000,
  accentColor = VESSELS_ACCENT,
  title,
  subtitle,
  evidenceDomain = 'vessels',
}: RiskSimulationPanelProps) {
  const [result, setResult] = useState<MonteCarloResult | null>(null);
  const [iterCount, setIterCount] = useState<number>(iterations);
  const [running, setRunning] = useState<boolean>(true);
  const [progress, setProgress] = useState<SimulationProgressState | null>(null);
  const [runKey, setRunKey] = useState<number>(0);
  const requestIdRef = useRef<number>(0);
  const [tweaks, setTweaks] = useState<Record<string, DriverTweak>>({});
  const [showTweaks, setShowTweaks] = useState<boolean>(false);
  const [appliedTweaks, setAppliedTweaks] = useState<Record<string, DriverTweak>>({});
  const [baseline, setBaseline] = useState<BaselineSnapshot | null>(null);

  useEffect(() => {
    setTweaks({});
    setAppliedTweaks({});
    setBaseline(null);
  }, [scenario.id]);

  const modifiedIds = useMemo(
    () => new Set(Object.keys(appliedTweaks).filter((id) => !isIdentityTweak(appliedTweaks[id]))),
    [appliedTweaks],
  );

  const effectiveScenario = useMemo<ScenarioDefinition>(() => {
    if (modifiedIds.size === 0) return scenario;
    const inputs = tweakedInputs(scenario.inputs, appliedTweaks);
    return { ...scenario, inputs };
  }, [scenario, appliedTweaks, modifiedIds]);

  useEffect(() => {
    setRunning(true);
    setProgress(null);
    const requestId = ++requestIdRef.current;
    const tweaksActive = modifiedIds.size > 0;
    let cancelled = false;

    // Workers only know registered scenarios by id and cannot apply
    // user-supplied driver tweaks, so we fall back to a synchronous run
    // on the main thread whenever overrides are in effect.
    if (!tweaksActive) {
      let workerCreationFailed = false;
      try {
        // Probe the worker constructor; if it throws we'll fall through
        // to the synchronous path below.
        new RiskSimulationWorker().terminate();
      } catch {
        workerCreationFailed = true;
      }
      if (!workerCreationFailed) {
        runScenarioInPool({
          scenario: effectiveScenario,
          iterations: iterCount,
          workerFactory: () => new RiskSimulationWorker(),
          onProgress: (p) => {
            if (cancelled || requestId !== requestIdRef.current) return;
            setProgress({ completed: p.completed, total: p.total });
          },
        })
          .then((r) => {
            if (cancelled || requestId !== requestIdRef.current) return;
            setResult(r);
            setProgress(null);
            setRunning(false);
          })
          .catch((_err) => {
            if (cancelled || requestId !== requestIdRef.current) return;
            try {
              const r = runScenarioSimulationSync(effectiveScenario, iterCount);
              if (requestId === requestIdRef.current) setResult(r);
            } finally {
              if (requestId === requestIdRef.current) {
                setProgress(null);
                setRunning(false);
              }
            }
          });
        return () => {
          cancelled = true;
        };
      }
    }

    // Fallback: synchronous run via setTimeout if workers are unavailable
    // or if driver tweaks are active.
    const handle = window.setTimeout(() => {
      try {
        const r = runScenarioSimulationSync(effectiveScenario, iterCount);
        if (requestId === requestIdRef.current) setResult(r);
      } finally {
        if (requestId === requestIdRef.current) {
          setProgress(null);
          setRunning(false);
        }
      }
    }, 30);
    return () => {
      cancelled = true;
      window.clearTimeout(handle);
    };
  }, [effectiveScenario, scenario.id, iterCount, runKey, modifiedIds]);

  const pendingChanges = useMemo(() => {
    const ids = new Set([...Object.keys(tweaks), ...Object.keys(appliedTweaks)]);
    for (const id of ids) {
      const a = tweaks[id] ?? IDENTITY_TWEAK;
      const b = appliedTweaks[id] ?? IDENTITY_TWEAK;
      if (Math.abs(a.meanMultiplier - b.meanMultiplier) > 1e-9) return true;
      if (Math.abs(a.spreadMultiplier - b.spreadMultiplier) > 1e-9) return true;
    }
    return false;
  }, [tweaks, appliedTweaks]);

  const updateTweak = (id: string, patch: Partial<DriverTweak>) => {
    setTweaks((prev) => {
      const current = prev[id] ?? IDENTITY_TWEAK;
      return { ...prev, [id]: { ...current, ...patch } };
    });
  };
  const resetInput = (id: string) => {
    setTweaks((prev) => ({ ...prev, [id]: { ...IDENTITY_TWEAK } }));
  };
  const resetAll = () => {
    setTweaks({});
    setAppliedTweaks({});
  };
  const applyAndRun = () => {
    setAppliedTweaks({ ...tweaks });
    setRunKey((k) => k + 1);
  };
  const captureBaseline = () => {
    if (!result) return;
    setBaseline({ result, capturedAt: Date.now(), tweakCount: modifiedIds.size });
  };
  const clearBaseline = () => setBaseline(null);
  const loadPresetTweaks = (preset: Record<string, DriverTweak>) => {
    setTweaks(preset);
    setAppliedTweaks(preset);
    setRunKey((k) => k + 1);
  };

  const primary = scenario.outputs[0];
  const primaryMetric = primary ? result?.metrics[primary.id] : undefined;

  const metricRows = useMemo(() => {
    if (!result) return [];
    return scenario.outputs
      .map((o) => ({
        id: o.id,
        label: o.label,
        format: o.format,
        stat: result.metrics[o.id],
      }))
      .filter((r) => r.stat);
  }, [result, scenario]);

  const maxP95 = useMemo(() => {
    const vals = metricRows.map((r) => Math.abs(r.stat?.p95 ?? 0));
    if (baseline) {
      for (const o of scenario.outputs) {
        const m = baseline.result.metrics[o.id];
        if (m) vals.push(Math.abs(m.p95));
      }
    }
    return Math.max(...vals, 0.0001);
  }, [metricRows, baseline, scenario]);

  const baselineCapturedLabel = useMemo(() => {
    if (!baseline) return null;
    const t = new Date(baseline.capturedAt);
    const hh = String(t.getHours()).padStart(2, '0');
    const mm = String(t.getMinutes()).padStart(2, '0');
    const ss = String(t.getSeconds()).padStart(2, '0');
    const tweakDesc =
      baseline.tweakCount === 0
        ? 'no tweaks'
        : `${baseline.tweakCount} tweak${baseline.tweakCount === 1 ? '' : 's'}`;
    return `Baseline captured ${hh}:${mm}:${ss} · ${tweakDesc}`;
  }, [baseline]);

  return (
    <div className="space-y-5">
      <div className="flex items-start justify-between gap-4 flex-wrap">
        <div>
          <h2 className="text-base font-semibold text-white tracking-tight">
            {title ?? scenario.title}
          </h2>
          <p className="text-[12px] mt-1 max-w-2xl" style={{ color: 'rgba(255,255,255,0.5)' }}>
            {subtitle ?? scenario.description}
          </p>
        </div>
        <div className="flex items-center gap-2">
          <select
            value={iterCount}
            onChange={(e) => setIterCount(Number(e.target.value))}
            className="text-[11px] bg-transparent border rounded-md px-2 py-1.5 font-mono text-white/80"
            style={{ borderColor: 'rgba(255,255,255,0.1)' }}
            aria-label="Monte Carlo iterations"
          >
            <option value={1000}>1,000 iter</option>
            <option value={5000}>5,000 iter</option>
            <option value={10000}>10,000 iter</option>
            <option value={25000}>25,000 iter</option>
            <option value={50000}>50,000 iter</option>
            <option value={100000}>100,000 iter</option>
          </select>
          <button
            onClick={() => setShowTweaks((s) => !s)}
            className="flex items-center gap-1.5 text-[11px] font-medium rounded-md px-2.5 py-1.5 transition-colors text-white/80 hover:text-white"
            style={{
              background: modifiedIds.size > 0 ? `${accentColor}20` : 'rgba(255,255,255,0.04)',
              border: `1px solid ${modifiedIds.size > 0 ? `${accentColor}40` : 'rgba(255,255,255,0.1)'}`,
            }}
            aria-label="Toggle driver tweaks"
            aria-expanded={showTweaks}
          >
            <Sliders className="w-3 h-3" />
            Tweak Drivers
            {modifiedIds.size > 0 && (
              <span
                className="ml-1 px-1.5 py-0.5 rounded text-[9px] font-mono"
                style={{ background: accentColor, color: '#000' }}
              >
                {modifiedIds.size}
              </span>
            )}
            {showTweaks ? <ChevronUp className="w-3 h-3" /> : <ChevronDown className="w-3 h-3" />}
          </button>
          <button
            onClick={() => setRunKey((k) => k + 1)}
            disabled={running}
            className="flex items-center gap-1.5 text-[11px] font-medium rounded-md px-2.5 py-1.5 transition-colors disabled:opacity-50"
            style={{
              background: `${accentColor}15`,
              color: accentColor,
              border: `1px solid ${accentColor}30`,
            }}
            aria-label="Re-run simulation"
          >
            <RefreshCw className={`w-3 h-3 ${running ? 'animate-spin' : ''}`} />
            {running
              ? progress
                ? `Running ${Math.round((progress.completed / progress.total) * 100)}%`
                : 'Running…'
              : 'Re-run'}
          </button>
          {baseline ? (
            <button
              onClick={clearBaseline}
              className="flex items-center gap-1.5 text-[11px] font-medium rounded-md px-2.5 py-1.5 transition-colors text-white/80 hover:text-white"
              style={{
                background: 'rgba(255,255,255,0.04)',
                border: '1px solid rgba(255,255,255,0.15)',
              }}
              aria-label="Clear saved baseline"
            >
              <X className="w-3 h-3" />
              Clear baseline
            </button>
          ) : (
            <button
              onClick={captureBaseline}
              disabled={running || !result}
              className="flex items-center gap-1.5 text-[11px] font-medium rounded-md px-2.5 py-1.5 transition-colors text-white/80 hover:text-white disabled:opacity-40"
              style={{
                background: 'rgba(255,255,255,0.04)',
                border: '1px solid rgba(255,255,255,0.15)',
              }}
              aria-label="Capture current run as baseline"
            >
              <BookmarkPlus className="w-3 h-3" />
              Capture baseline
            </button>
          )}
          <SaveRiskRunButton
            domain={evidenceDomain}
            accentColor={accentColor}
            disabled={running || !result}
            build={() => {
              if (!result) return null;
              const payload: Omit<SavedRiskRun, 'evidenceId' | 'savedAt'> = {
                scenarioId: scenario.id,
                scenarioVersion: scenario.version,
                scenarioTitle: title ?? scenario.title,
                domain: scenario.domain,
                iterations: result.iterations,
                validIterations: result.validIterations,
                durationMs: result.durationMs,
                metrics: scenario.outputs
                  .map((o) => {
                    const m = result.metrics[o.id];
                    if (!m) return null;
                    return {
                      id: o.id,
                      label: m.label,
                      format: m.format,
                      mean: m.mean,
                      p5: m.p5,
                      p25: m.p25,
                      p50: m.p50,
                      p75: m.p75,
                      p95: m.p95,
                      min: m.min,
                      max: m.max,
                      stdDev: m.stdDev,
                    };
                  })
                  .filter((x): x is NonNullable<typeof x> => x !== null),
                sensitivities: result.inputSensitivity.map((s) => ({
                  inputId: s.inputId,
                  label: s.label,
                  impact: s.impact,
                })),
                inputs: effectiveScenario.inputs.map((inp) => ({
                  id: inp.id,
                  label: inp.label,
                  unit: inp.unit,
                  format: inp.format,
                  distribution: inp.distribution,
                })),
              };
              return payload;
            }}
          />
        </div>
      </div>

      {showTweaks && (
        <DriverTweaksPanel
          inputs={scenario.inputs}
          tweaks={tweaks}
          accentColor={accentColor}
          onChange={updateTweak}
          onResetInput={resetInput}
          onResetAll={resetAll}
          onApply={applyAndRun}
          pendingChanges={pendingChanges}
          modifiedIds={modifiedIds}
          running={running}
          presetScopeKey={`${evidenceDomain}:${scenario.id}`}
          onLoadPreset={loadPresetTweaks}
        />
      )}

      <div
        className="rounded-xl border p-4 grid grid-cols-2 md:grid-cols-4 gap-4"
        style={{ borderColor: 'rgba(255,255,255,0.08)', background: 'rgba(255,255,255,0.02)' }}
      >
        <div>
          <div
            className="text-[9px] uppercase tracking-wider mb-1"
            style={{ color: 'rgba(255,255,255,0.4)' }}
          >
            Iterations
          </div>
          <div className="text-sm font-mono text-white">
            {running && progress
              ? `${progress.completed.toLocaleString()} / ${progress.total.toLocaleString()}`
              : (result?.iterations.toLocaleString() ?? '—')}
          </div>
          {running && progress && (
            <div
              className="mt-1.5 h-1 rounded-full overflow-hidden"
              style={{ background: 'rgba(255,255,255,0.06)' }}
              role="progressbar"
              aria-label="Simulation progress"
              aria-valuemin={0}
              aria-valuemax={progress.total}
              aria-valuenow={progress.completed}
            >
              <div
                className="h-full rounded-full transition-[width] duration-200 ease-out"
                style={{
                  width: `${Math.min(100, (progress.completed / progress.total) * 100)}%`,
                  background: accentColor,
                }}
              />
            </div>
          )}
        </div>
        <div>
          <div
            className="text-[9px] uppercase tracking-wider mb-1"
            style={{ color: 'rgba(255,255,255,0.4)' }}
          >
            Valid Runs
          </div>
          <div className="text-sm font-mono text-white">
            {result?.validIterations.toLocaleString() ?? '—'}
          </div>
        </div>
        <div>
          <div
            className="text-[9px] uppercase tracking-wider mb-1"
            style={{ color: 'rgba(255,255,255,0.4)' }}
          >
            Compute
          </div>
          <div className="text-sm font-mono text-white">
            {result ? `${result.durationMs.toFixed(0)}ms` : '—'}
          </div>
        </div>
        <div>
          <div
            className="text-[9px] uppercase tracking-wider mb-1"
            style={{ color: 'rgba(255,255,255,0.4)' }}
          >
            Domain
          </div>
          <div className="text-sm font-mono uppercase" style={{ color: accentColor }}>
            {result?.domain ?? scenario.domain}
          </div>
        </div>
      </div>

      <div
        className="rounded-xl border p-5"
        style={{ borderColor: 'rgba(255,255,255,0.08)', background: 'rgba(255,255,255,0.02)' }}
      >
        <div className="flex items-center gap-2 mb-4">
          <BarChart3 className="w-3.5 h-3.5" style={{ color: accentColor }} />
          <h3
            className="text-[10px] font-semibold uppercase tracking-wider"
            style={{ color: 'rgba(255,255,255,0.55)' }}
          >
            Output Distributions — {result?.scenarioId ?? scenario.id}
          </h3>
        </div>
        {baselineCapturedLabel && (
          <div
            className="flex items-center justify-between gap-3 mb-3 px-2.5 py-1.5 rounded-md text-[10px] font-mono"
            style={{
              background: 'rgba(255,255,255,0.04)',
              border: '1px solid rgba(255,255,255,0.08)',
              color: 'rgba(255,255,255,0.6)',
            }}
          >
            <span className="flex items-center gap-2">
              <span
                className="inline-block w-2 h-2 rounded-sm"
                style={{ background: 'rgba(255,255,255,0.35)' }}
              />
              {baselineCapturedLabel}
            </span>
            <span className="flex items-center gap-2" style={{ color: accentColor }}>
              <span
                className="inline-block w-2 h-2 rounded-sm"
                style={{ background: accentColor }}
              />
              current run
            </span>
          </div>
        )}
        <div className="space-y-4">
          {metricRows.map(({ id, label, format, stat }, rowIdx) => {
            if (!stat) return null;
            const baseStat = baseline?.result.metrics[id];
            const p95 = Math.abs(stat.p95);
            const p5 = Math.abs(stat.p5);
            const mean = Math.abs(stat.mean);
            const p95Pct = maxP95 > 0 ? Math.min(100, (p95 / maxP95) * 100) : 0;
            const p5Pct = maxP95 > 0 ? Math.min(100, (p5 / maxP95) * 100) : 0;
            const iqrPct = Math.max(0, p95Pct - p5Pct);
            const meanPct = maxP95 > 0 ? Math.min(100, (mean / maxP95) * 100) : 0;
            const delay = rowIdx * 0.1;
            const meanDelta = baseStat ? stat.mean - baseStat.mean : 0;
            return (
              <div key={id}>
                <div className="flex items-center justify-between mb-1.5">
                  <span className="text-[12px] font-semibold text-white">{label}</span>
                  <span className="text-sm font-bold text-white flex items-baseline gap-2">
                    {formatValue(stat.mean, format)}{' '}
                    <span
                      className="text-[10px] font-normal"
                      style={{ color: 'rgba(255,255,255,0.4)' }}
                    >
                      (mean)
                    </span>
                    {baseStat && (
                      <span
                        className="text-[10px] font-mono px-1.5 py-0.5 rounded"
                        style={{
                          color: accentColor,
                          background: `${accentColor}15`,
                          border: `1px solid ${accentColor}30`,
                        }}
                        title={`Baseline mean ${formatValue(baseStat.mean, format)}`}
                      >
                        Δ {formatSignedValue(meanDelta, format)} (
                        {formatPctDelta(stat.mean, baseStat.mean)})
                      </span>
                    )}
                  </span>
                </div>
                <div
                  className="relative h-6 rounded-md overflow-hidden"
                  style={{ background: 'rgba(255,255,255,0.05)' }}
                >
                  <motion.div
                    className="absolute top-0 left-0 h-full rounded-md"
                    style={{ background: `${accentColor}33` }}
                    initial={{ width: 0 }}
                    animate={{ width: `${p95Pct}%` }}
                    transition={{ duration: 0.7, delay, ease: 'easeOut' }}
                  />
                  <motion.div
                    className="absolute top-1 bottom-1 rounded-sm"
                    style={{ background: `${accentColor}66`, left: `${p5Pct}%` }}
                    initial={{ width: 0 }}
                    animate={{ width: `${iqrPct}%` }}
                    transition={{ duration: 0.7, delay: delay + 0.1, ease: 'easeOut' }}
                  />
                  <motion.div
                    className="absolute top-0 bottom-0 w-0.5 bg-white"
                    initial={{ left: 0, opacity: 0 }}
                    animate={{ left: `${meanPct}%`, opacity: 1 }}
                    transition={{ duration: 0.7, delay: delay + 0.2, ease: 'easeOut' }}
                  />
                </div>
                {baseStat &&
                  (() => {
                    const bP95 = Math.abs(baseStat.p95);
                    const bP5 = Math.abs(baseStat.p5);
                    const bMean = Math.abs(baseStat.mean);
                    const bP95Pct = maxP95 > 0 ? Math.min(100, (bP95 / maxP95) * 100) : 0;
                    const bP5Pct = maxP95 > 0 ? Math.min(100, (bP5 / maxP95) * 100) : 0;
                    const bIqrPct = Math.max(0, bP95Pct - bP5Pct);
                    const bMeanPct = maxP95 > 0 ? Math.min(100, (bMean / maxP95) * 100) : 0;
                    return (
                      <div
                        className="relative h-3 rounded-md overflow-hidden mt-1"
                        style={{ background: 'rgba(255,255,255,0.03)' }}
                      >
                        <div
                          className="absolute top-0 left-0 h-full rounded-md"
                          style={{ background: 'rgba(255,255,255,0.10)', width: `${bP95Pct}%` }}
                        />
                        <div
                          className="absolute top-0.5 bottom-0.5 rounded-sm"
                          style={{
                            background: 'rgba(255,255,255,0.25)',
                            left: `${bP5Pct}%`,
                            width: `${bIqrPct}%`,
                          }}
                        />
                        <div
                          className="absolute top-0 bottom-0 w-0.5"
                          style={{ background: 'rgba(255,255,255,0.6)', left: `${bMeanPct}%` }}
                        />
                      </div>
                    );
                  })()}
                <div
                  className="flex justify-between text-[9px] mt-1 font-mono"
                  style={{ color: 'rgba(255,255,255,0.4)' }}
                >
                  <span>P5: {formatValue(stat.p5, format)}</span>
                  <span>P25: {formatValue(stat.p25, format)}</span>
                  <span>P50: {formatValue(stat.p50, format)}</span>
                  <span>P75: {formatValue(stat.p75, format)}</span>
                  <span>P95: {formatValue(stat.p95, format)}</span>
                </div>
                {baseStat && (
                  <div
                    className="flex justify-between text-[9px] mt-0.5 font-mono"
                    style={{ color: 'rgba(255,255,255,0.3)' }}
                  >
                    <span>base P5: {formatValue(baseStat.p5, format)}</span>
                    <span>P25: {formatValue(baseStat.p25, format)}</span>
                    <span>P50: {formatValue(baseStat.p50, format)}</span>
                    <span>P75: {formatValue(baseStat.p75, format)}</span>
                    <span>P95: {formatValue(baseStat.p95, format)}</span>
                  </div>
                )}
              </div>
            );
          })}
        </div>
      </div>

      <div className="grid grid-cols-1 md:grid-cols-3 gap-3">
        <div
          className="md:col-span-2 rounded-xl border p-4"
          style={{ borderColor: 'rgba(255,255,255,0.08)', background: 'rgba(255,255,255,0.02)' }}
        >
          <div className="flex items-center gap-2 mb-3">
            <Layers className="w-3.5 h-3.5" style={{ color: accentColor }} />
            <h4
              className="text-[10px] font-semibold uppercase tracking-wider"
              style={{ color: 'rgba(255,255,255,0.55)' }}
            >
              Input Sensitivity{primary ? ` (Correlation to ${primary.label})` : ''}
            </h4>
          </div>
          <div className="space-y-2">
            {result?.inputSensitivity.slice(0, 8).map((item, i) => (
              <div key={item.inputId} className="flex items-center gap-2">
                <span
                  className="text-[11px] w-44 truncate flex-shrink-0 flex items-center gap-1.5"
                  style={{ color: 'rgba(255,255,255,0.6)' }}
                >
                  {item.label}
                  {modifiedIds.has(item.inputId) && (
                    <span
                      className="px-1 py-0.5 rounded text-[8px] font-mono uppercase tracking-wider"
                      style={{ background: `${accentColor}30`, color: accentColor }}
                    >
                      tweaked
                    </span>
                  )}
                </span>
                <div
                  className="flex-1 h-3 rounded-full overflow-hidden"
                  style={{ background: 'rgba(255,255,255,0.05)' }}
                >
                  <motion.div
                    className="h-full rounded-full"
                    style={{ background: accentColor, opacity: 0.7 }}
                    initial={{ width: 0 }}
                    animate={{ width: `${Math.min(100, item.impact * 100)}%` }}
                    transition={{ duration: 0.6, delay: i * 0.05, ease: 'easeOut' }}
                  />
                </div>
                <span className="text-[10px] font-mono w-10 text-right text-white">
                  {(item.impact * 100).toFixed(0)}%
                </span>
              </div>
            )) ?? null}
            {!result && (
              <p className="text-[11px]" style={{ color: 'rgba(255,255,255,0.3)' }}>
                Sampling driver impact…
              </p>
            )}
          </div>
        </div>
        <div
          className="rounded-xl border p-4 flex flex-col gap-3"
          style={{ borderColor: 'rgba(255,255,255,0.08)', background: 'rgba(255,255,255,0.02)' }}
        >
          <div className="flex items-center gap-2 mb-1">
            <Activity className="w-3.5 h-3.5" style={{ color: accentColor }} />
            <h4
              className="text-[10px] font-semibold uppercase tracking-wider"
              style={{ color: 'rgba(255,255,255,0.55)' }}
            >
              Risk Bands
            </h4>
          </div>
          {primary &&
            primaryMetric &&
            (() => {
              const basePrimary = baseline?.result.metrics[primary.id];
              const renderDelta = (curr: number, base: number | undefined) => {
                if (base === undefined || !Number.isFinite(base)) return null;
                return (
                  <span
                    className="ml-2 text-[9px] font-mono px-1 py-0.5 rounded"
                    style={{
                      color: accentColor,
                      background: `${accentColor}15`,
                      border: `1px solid ${accentColor}30`,
                    }}
                  >
                    Δ {formatSignedValue(curr - base, primary.format)} ({formatPctDelta(curr, base)}
                    )
                  </span>
                );
              };
              const baseLine = (text: string) => (
                <div
                  className="text-[10px] font-mono mt-0.5"
                  style={{ color: 'rgba(255,255,255,0.4)' }}
                >
                  base · {text}
                </div>
              );
              return (
                <>
                  <div>
                    <div
                      className="text-[9px] uppercase tracking-wider mb-1"
                      style={{ color: 'rgba(255,255,255,0.4)' }}
                    >
                      Standard Deviation
                    </div>
                    <div className="text-sm font-bold text-white flex items-center flex-wrap">
                      {formatValue(primaryMetric.stdDev, primary.format)}
                      {renderDelta(primaryMetric.stdDev, basePrimary?.stdDev)}
                    </div>
                    {basePrimary && baseLine(formatValue(basePrimary.stdDev, primary.format))}
                  </div>
                  <div>
                    <div
                      className="text-[9px] uppercase tracking-wider mb-1"
                      style={{ color: 'rgba(255,255,255,0.4)' }}
                    >
                      90% Confidence Band
                    </div>
                    <div className="text-sm font-semibold text-white flex items-center flex-wrap">
                      {formatValue(primaryMetric.p5, primary.format)} –{' '}
                      {formatValue(primaryMetric.p95, primary.format)}
                      {renderDelta(
                        primaryMetric.p95 - primaryMetric.p5,
                        basePrimary ? basePrimary.p95 - basePrimary.p5 : undefined,
                      )}
                    </div>
                    {basePrimary &&
                      baseLine(
                        `${formatValue(basePrimary.p5, primary.format)} – ${formatValue(basePrimary.p95, primary.format)}`,
                      )}
                  </div>
                  <div>
                    <div
                      className="text-[9px] uppercase tracking-wider mb-1"
                      style={{ color: 'rgba(255,255,255,0.4)' }}
                    >
                      50% Interquartile
                    </div>
                    <div className="text-sm font-semibold text-white flex items-center flex-wrap">
                      {formatValue(primaryMetric.p25, primary.format)} –{' '}
                      {formatValue(primaryMetric.p75, primary.format)}
                      {renderDelta(
                        primaryMetric.p75 - primaryMetric.p25,
                        basePrimary ? basePrimary.p75 - basePrimary.p25 : undefined,
                      )}
                    </div>
                    {basePrimary &&
                      baseLine(
                        `${formatValue(basePrimary.p25, primary.format)} – ${formatValue(basePrimary.p75, primary.format)}`,
                      )}
                  </div>
                  <div>
                    <div
                      className="text-[9px] uppercase tracking-wider mb-1"
                      style={{ color: 'rgba(255,255,255,0.4)' }}
                    >
                      Range
                    </div>
                    <div className="text-sm font-mono text-white">
                      {formatValue(primaryMetric.min, primary.format)} →{' '}
                      {formatValue(primaryMetric.max, primary.format)}
                    </div>
                    {basePrimary &&
                      baseLine(
                        `${formatValue(basePrimary.min, primary.format)} → ${formatValue(basePrimary.max, primary.format)}`,
                      )}
                  </div>
                  <div>
                    <div
                      className="text-[9px] uppercase tracking-wider mb-1"
                      style={{ color: 'rgba(255,255,255,0.4)' }}
                    >
                      Mean
                    </div>
                    <div className="text-sm font-bold text-white flex items-center flex-wrap">
                      {formatValue(primaryMetric.mean, primary.format)}
                      {renderDelta(primaryMetric.mean, basePrimary?.mean)}
                    </div>
                    {basePrimary && baseLine(formatValue(basePrimary.mean, primary.format))}
                  </div>
                </>
              );
            })()}
        </div>
      </div>
    </div>
  );
}

interface DriverTweaksPanelProps {
  inputs: InputVariable[];
  tweaks: Record<string, DriverTweak>;
  accentColor: string;
  onChange: (id: string, patch: Partial<DriverTweak>) => void;
  onResetInput: (id: string) => void;
  onResetAll: () => void;
  onApply: () => void;
  pendingChanges: boolean;
  modifiedIds: Set<string>;
  running: boolean;
  presetScopeKey: string;
  onLoadPreset: (tweaks: Record<string, DriverTweak>) => void;
}

function formatDriverValue(value: number, format?: string): string {
  if (!Number.isFinite(value)) return '—';
  if (format === 'currency') {
    const abs = Math.abs(value);
    if (abs >= 1_000_000) return `$${(value / 1_000_000).toFixed(2)}M`;
    if (abs >= 1000) return `$${(value / 1000).toFixed(1)}K`;
    return `$${value.toFixed(2)}`;
  }
  if (format === 'percentage') return `${(value * 100).toFixed(1)}%`;
  if (format === 'years') return `${value.toFixed(1)}y`;
  return value.toLocaleString(undefined, { maximumFractionDigits: 3 });
}

function DriverTweaksPanel({
  inputs,
  tweaks,
  accentColor,
  onChange,
  onResetInput,
  onResetAll,
  onApply,
  pendingChanges,
  modifiedIds,
  running,
  presetScopeKey,
  onLoadPreset,
}: DriverTweaksPanelProps) {
  return (
    <div
      className="rounded-xl border p-4"
      style={{ borderColor: `${accentColor}30`, background: `${accentColor}08` }}
    >
      <div className="flex items-center justify-between gap-2 mb-3 flex-wrap">
        <div className="flex items-center gap-2">
          <Sliders className="w-3.5 h-3.5" style={{ color: accentColor }} />
          <h4
            className="text-[10px] font-semibold uppercase tracking-wider"
            style={{ color: 'rgba(255,255,255,0.7)' }}
          >
            Driver Assumptions — override before re-running
          </h4>
        </div>
        <div className="flex items-center gap-2 flex-wrap">
          <DriverTweakPresets
            scopeKey={presetScopeKey}
            accentColor={accentColor}
            currentTweaks={tweaks}
            onLoad={onLoadPreset}
          />
          <button
            onClick={onResetAll}
            className="flex items-center gap-1 text-[10px] font-medium rounded-md px-2 py-1 transition-colors text-white/70 hover:text-white"
            style={{
              background: 'rgba(255,255,255,0.05)',
              border: '1px solid rgba(255,255,255,0.1)',
            }}
            aria-label="Reset all drivers to baseline"
          >
            <RotateCcw className="w-3 h-3" />
            Reset to baseline
          </button>
          <button
            onClick={onApply}
            disabled={running || !pendingChanges}
            className="flex items-center gap-1 text-[10px] font-semibold rounded-md px-2.5 py-1 transition-colors disabled:opacity-40"
            style={{ background: accentColor, color: '#000' }}
            aria-label="Apply tweaks and re-run simulation"
          >
            <RefreshCw className={`w-3 h-3 ${running ? 'animate-spin' : ''}`} />
            {pendingChanges ? 'Apply & re-run' : 'No changes'}
          </button>
        </div>
      </div>

      <div className="grid grid-cols-1 md:grid-cols-2 gap-x-5 gap-y-3">
        {inputs.map((inp) => {
          const t = tweaks[inp.id] ?? IDENTITY_TWEAK;
          const baseline = tweakSummary(inp.distribution);
          const projectedCenter = baseline.center * t.meanMultiplier;
          const projectedSpread = baseline.spread * t.spreadMultiplier;
          const supportsSpread = distributionSupportsSpread(inp.distribution);
          const isModified = modifiedIds.has(inp.id) || !isIdentityTweak(t);
          return (
            <div
              key={inp.id}
              className="rounded-md p-2.5"
              style={{
                background: 'rgba(0,0,0,0.25)',
                border: `1px solid ${isModified ? `${accentColor}40` : 'rgba(255,255,255,0.06)'}`,
              }}
            >
              <div className="flex items-center justify-between gap-2 mb-1.5">
                <div className="flex items-center gap-1.5 min-w-0">
                  <span className="text-[11px] font-medium text-white truncate">{inp.label}</span>
                  {isModified && (
                    <span
                      className="px-1 py-0.5 rounded text-[8px] font-mono uppercase"
                      style={{ background: `${accentColor}30`, color: accentColor }}
                    >
                      modified
                    </span>
                  )}
                </div>
                <button
                  onClick={() => onResetInput(inp.id)}
                  className="text-[9px] text-white/40 hover:text-white/80 transition-colors flex-shrink-0"
                  aria-label={`Reset ${inp.label}`}
                >
                  reset
                </button>
              </div>
              <div
                className="flex items-center justify-between text-[9px] font-mono mb-2"
                style={{ color: 'rgba(255,255,255,0.5)' }}
              >
                <span>
                  baseline {formatDriverValue(baseline.center, inp.format)}
                  {supportsSpread && baseline.spread > 0
                    ? ` ± ${formatDriverValue(baseline.spread, inp.format)}`
                    : ''}
                </span>
                <span style={{ color: isModified ? accentColor : 'rgba(255,255,255,0.5)' }}>
                  → {formatDriverValue(projectedCenter, inp.format)}
                  {supportsSpread && projectedSpread > 0
                    ? ` ± ${formatDriverValue(projectedSpread, inp.format)}`
                    : ''}
                </span>
              </div>
              <div className="space-y-1.5">
                <div className="flex items-center gap-2">
                  <span
                    className="text-[9px] uppercase tracking-wider w-12 flex-shrink-0"
                    style={{ color: 'rgba(255,255,255,0.45)' }}
                  >
                    Mean
                  </span>
                  <input
                    type="range"
                    min={0.5}
                    max={1.5}
                    step={0.01}
                    value={t.meanMultiplier}
                    onChange={(e) => onChange(inp.id, { meanMultiplier: Number(e.target.value) })}
                    className="flex-1 accent-current"
                    style={{ accentColor }}
                    aria-label={`${inp.label} mean multiplier`}
                  />
                  <span
                    className="text-[10px] font-mono w-12 text-right"
                    style={{
                      color:
                        Math.abs(t.meanMultiplier - 1) > 1e-9
                          ? accentColor
                          : 'rgba(255,255,255,0.6)',
                    }}
                  >
                    {(t.meanMultiplier * 100).toFixed(0)}%
                  </span>
                </div>
                {supportsSpread && (
                  <div className="flex items-center gap-2">
                    <span
                      className="text-[9px] uppercase tracking-wider w-12 flex-shrink-0"
                      style={{ color: 'rgba(255,255,255,0.45)' }}
                    >
                      Spread
                    </span>
                    <input
                      type="range"
                      min={0}
                      max={3}
                      step={0.05}
                      value={t.spreadMultiplier}
                      onChange={(e) =>
                        onChange(inp.id, { spreadMultiplier: Number(e.target.value) })
                      }
                      className="flex-1"
                      style={{ accentColor }}
                      aria-label={`${inp.label} spread multiplier`}
                    />
                    <span
                      className="text-[10px] font-mono w-12 text-right"
                      style={{
                        color:
                          Math.abs(t.spreadMultiplier - 1) > 1e-9
                            ? accentColor
                            : 'rgba(255,255,255,0.6)',
                      }}
                    >
                      {t.spreadMultiplier.toFixed(2)}×
                    </span>
                  </div>
                )}
              </div>
            </div>
          );
        })}
      </div>
    </div>
  );
}