import React, { useState, useEffect } from 'react';
import { useApp } from '../context/AppContext';
import { Sparkles, Upload, FileText, CheckCircle2, AlertTriangle, X, Loader2, TrendingUp, Sliders, Info } from 'lucide-react';
import confetti from 'canvas-confetti';
import { getAiConfig } from '../services/ai';

const tl = (n) => (typeof n === 'number' && isFinite(n) ? '₺' + n.toLocaleString('tr-TR') : '—');

export const AiSpecAnalyzerModal = () => {
  const {
    isAiSpecAnalyzerOpen, setIsAiSpecAnalyzerOpen,
    analyzeSpecPdfWithGemini, aiAnalysisResults, activeAiModel, activeTenderDetail,
  } = useApp();

  const [isAnalyzing, setIsAnalyzing] = useState(false);
  const [selectedFile, setSelectedFile] = useState(null);
  const [error, setError] = useState(null);
  const [progress, setProgress] = useState('');
  const [customBid, setCustomBid] = useState(null);
  const [aiCfg, setAiCfg] = useState(null);

  useEffect(() => {
    if (isAiSpecAnalyzerOpen && aiCfg === null) getAiConfig().then(setAiCfg);
  }, [isAiSpecAnalyzerOpen, aiCfg]);

  if (!isAiSpecAnalyzerOpen) return null;

  const results = aiAnalysisResults;
  const bid = results?.bidAnalysis || {};

  const runAnalysis = async (text, fileName) => {
    setError(null);
    setIsAnalyzing(true);
    setSelectedFile(fileName);
    try {
      setProgress('Model analiz ediyor…');
      const r = await analyzeSpecPdfWithGemini({ text, fileName, tender: activeTenderDetail });
      if (typeof r?.bidAnalysis?.recommendedBid === 'number') setCustomBid(r.bidAnalysis.recommendedBid);
      confetti({ particleCount: 80, spread: 70 });
    } catch (e) {
      setError(e.message);
    } finally {
      setIsAnalyzing(false);
      setProgress('');
    }
  };

  const handleFile = async (file) => {
    setError(null);
    setIsAnalyzing(true);
    setSelectedFile(file.name);
    try {
      setProgress('Belge metni çıkarılıyor…');
      const { extractText } = await import('../services/pdfText');
      const { text, usedPages, pageCount } = await extractText(file);
      if (!text || text.length < 40) {
        throw new Error('Belgeden metin çıkarılamadı. Taranmış (görüntü) PDF olabilir — metin tabanlı bir dosya deneyin.');
      }
      setProgress(`${usedPages}/${pageCount} sayfa okundu, model analiz ediyor…`);
      const r = await analyzeSpecPdfWithGemini({ text, fileName: file.name, tender: activeTenderDetail });
      if (typeof r?.bidAnalysis?.recommendedBid === 'number') setCustomBid(r.bidAnalysis.recommendedBid);
      confetti({ particleCount: 80, spread: 70 });
    } catch (e) {
      setError(e.message);
    } finally {
      setIsAnalyzing(false);
      setProgress('');
    }
  };

  // Açık ihalenin ilan metnini analiz et
  const analyzeCurrentTender = () => {
    const t = activeTenderDetail;
    const text = [t?.baslik, t?.kurum, t?.aciklama, ...(t?.yeterlikKriterleri || [])].filter(Boolean).join('\n');
    if (!text || text.length < 40) {
      setError('Açık ihalenin ilan metni analiz için yeterli değil. Bir şartname dosyası yükleyin.');
      return;
    }
    runAnalysis(text, `${t.ikn || 'ihale'} — ilan metni`);
  };

  const modelEtiketi = aiCfg?.providers?.length
    ? aiCfg.providers.map((p) => p.label).join(' → ')
    : `${activeAiModel.label} (${activeAiModel.provider})`;

  return (
    <div className="fixed inset-0 z-50 flex items-center justify-center p-4 bg-slate-900/75 backdrop-blur-xs animate-fade-in">
      <div className="bg-white rounded-2xl border border-slate-200 shadow-2xl w-full max-w-4xl overflow-hidden my-auto flex flex-col max-h-[92vh]">

        {/* Header */}
        <div className="bg-linear-to-r from-blue-900 via-indigo-900 to-purple-900 text-white px-6 py-4 flex items-center justify-between border-b border-indigo-800">
          <div className="flex items-center gap-3">
            <div className="w-10 h-10 rounded-xl bg-amber-400 text-slate-900 flex items-center justify-center shadow-md font-black">
              <Sparkles className="w-6 h-6" />
            </div>
            <div>
              <div className="flex items-center gap-2 flex-wrap">
                <h2 className="font-extrabold text-base">Teknik Şartname & Teklif Analiz Asistanı</h2>
                <span className="bg-amber-400 text-slate-900 text-[10px] font-black px-2 py-0.5 rounded-full uppercase tracking-wider">
                  {modelEtiketi}
                </span>
              </div>
              <p className="text-xs text-blue-200">Şartname dosyanızı yükleyin; yeterlik, riskler ve teklif aralığı gerçek AI ile analiz edilsin.</p>
            </div>
          </div>
          <button onClick={() => setIsAiSpecAnalyzerOpen(false)} className="text-slate-400 hover:text-white p-1 rounded-lg transition-colors">
            <X className="w-6 h-6" />
          </button>
        </div>

        <div className="p-6 space-y-6 overflow-y-auto">

          {/* AI yapılandırılmamış uyarısı */}
          {aiCfg && !aiCfg.configured && (
            <div className="bg-amber-50 border border-amber-200 rounded-xl p-4 flex gap-3">
              <Info className="w-4 h-4 text-amber-700 shrink-0 mt-0.5" />
              <p className="text-xs text-amber-900 leading-relaxed">
                <strong>AI henüz yapılandırılmamış.</strong> En kolayı: sunucuya tek bir{' '}
                <code className="bg-amber-100 px-1 rounded">OPENROUTER_API_KEY</code> ekleyin —
                zincirdeki tüm modeller (GLM, DeepSeek, Gemini, Grok, GPT, Claude) bu tek anahtarla çalışır.
                Dilerseniz tek tek sağlayıcı anahtarı da verebilirsiniz; doğrudan anahtar OpenRouter'ı ezer.
                Model sırası Admin → AI Model Ayarları'ndan belirlenir.</p>
            </div>
          )}

          {/* Uploader */}
          <div className="bg-slate-50 border-2 border-dashed border-blue-300 hover:border-blue-500 rounded-2xl p-6 text-center space-y-3 transition-colors">
            <div className="w-12 h-12 rounded-2xl bg-blue-100 text-blue-600 flex items-center justify-center mx-auto shadow-xs">
              <Upload className="w-6 h-6" />
            </div>
            <div>
              <h3 className="font-bold text-sm text-slate-800">Teknik Şartname Dosyası Yükleyin</h3>
              <p className="text-xs text-slate-500">Metin tabanlı <code>.pdf</code> veya <code>.txt</code> dosyası — belge tarayıcınızda okunur, yalnızca metni analiz için gönderilir.</p>
            </div>

            <div className="flex justify-center gap-3 pt-2 flex-wrap">
              <label className={`font-extrabold text-xs px-5 py-2.5 rounded-xl shadow-md transition-colors flex items-center gap-2 ${
                isAnalyzing ? 'bg-slate-300 text-slate-500 cursor-not-allowed' : 'bg-blue-600 hover:bg-blue-500 text-white cursor-pointer'
              }`}>
                <Upload className="w-4 h-4" />
                <span>Dosya Seç (PDF / TXT)</span>
                <input
                  type="file"
                  accept=".pdf,.txt,.md"
                  className="hidden"
                  disabled={isAnalyzing}
                  onChange={(e) => { if (e.target.files?.[0]) handleFile(e.target.files[0]); }}
                />
              </label>

              {activeTenderDetail && (
                <button
                  type="button"
                  disabled={isAnalyzing}
                  onClick={analyzeCurrentTender}
                  className="bg-white hover:bg-slate-100 disabled:opacity-50 text-slate-700 font-bold text-xs px-4 py-2.5 rounded-xl border border-slate-300 transition-colors flex items-center gap-2"
                >
                  <FileText className="w-4 h-4 text-purple-600" />
                  <span>Açık İhalenin İlan Metnini Analiz Et</span>
                </button>
              )}
            </div>
          </div>

          {/* Hata */}
          {error && (
            <div className="bg-red-50 border border-red-200 rounded-xl p-4 flex gap-3">
              <AlertTriangle className="w-4 h-4 text-red-600 shrink-0 mt-0.5" />
              <div>
                <p className="text-xs font-bold text-red-900">Analiz tamamlanamadı</p>
                <p className="text-xs text-red-800 mt-0.5 leading-relaxed">{error}</p>
              </div>
            </div>
          )}

          {/* Yükleniyor */}
          {isAnalyzing && (
            <div className="bg-linear-to-r from-blue-50 to-indigo-50 border border-blue-200 p-6 rounded-2xl space-y-2 animate-fade-in shadow-xs">
              <div className="flex items-center gap-2 font-extrabold text-xs text-blue-900">
                <Loader2 className="w-5 h-5 text-blue-600 animate-spin" />
                <span>{progress || 'İşleniyor…'}</span>
              </div>
              <p className="text-xs text-slate-600">{selectedFile}</p>
            </div>
          )}

          {/* Sonuç */}
          {!isAnalyzing && results && (
            <div className="space-y-6 animate-fade-in">

              <div className="bg-slate-900 text-white p-5 rounded-2xl space-y-3 shadow-md">
                <div className="flex items-center justify-between border-b border-slate-800 pb-2 gap-2 flex-wrap">
                  <span className="text-xs font-extrabold text-amber-400 uppercase tracking-wider flex items-center gap-1.5">
                    <Sparkles className="w-4 h-4" /> Şartname Özeti
                  </span>
                  <span className="text-[10px] text-slate-400">
                    {results.model} · {results.analyzedAt}
                  </span>
                </div>
                <p className="text-xs text-slate-300 leading-relaxed font-medium">{results.summary || 'Özet üretilemedi.'}</p>
                {results.fileName && <p className="text-[10px] text-slate-500">Kaynak: {results.fileName}</p>}
              </div>

              {/* Teklif analizi — yalnızca model sayı ürettiyse */}
              {(bid.estimatedCost != null || bid.recommendedBid != null) && (
                <div className="bg-linear-to-br from-emerald-950 via-slate-900 to-blue-950 text-white p-6 rounded-2xl space-y-4 shadow-xl border border-emerald-800/40">
                  <div className="flex items-center justify-between gap-2 flex-wrap">
                    <div className="flex items-center gap-2">
                      <TrendingUp className="w-5 h-5 text-emerald-400" />
                      <h3 className="font-black text-base">Önerilen Teklif Aralığı</h3>
                    </div>
                    {bid.winProbability != null && (
                      <span className="bg-emerald-500 text-slate-950 font-black text-xs px-3 py-1 rounded-full shadow-xs">
                        %{bid.winProbability} Kazanma Tahmini
                      </span>
                    )}
                  </div>

                  <div className="grid grid-cols-1 md:grid-cols-3 gap-4 pt-2">
                    <div className="bg-white/10 p-3.5 rounded-xl border border-white/10">
                      <span className="text-[11px] text-slate-300 font-medium block">İdare Yaklaşık Maliyeti</span>
                      <span className="text-base font-black text-white mt-1 block">{tl(bid.estimatedCost)}</span>
                    </div>
                    <div className="bg-emerald-500/20 p-3.5 rounded-xl border border-emerald-400/40">
                      <span className="text-[11px] text-emerald-300 font-bold block">Önerilen Optimal Teklif</span>
                      <span className="text-xl font-black text-amber-300 mt-0.5 block">{tl(bid.recommendedBid)}</span>
                    </div>
                    <div className="bg-white/10 p-3.5 rounded-xl border border-white/10">
                      <span className="text-[11px] text-slate-300 font-medium block">Rekabet Değerlendirmesi</span>
                      <span className="text-xs font-bold text-blue-300 mt-1 block leading-snug">{bid.competitionLevel || '—'}</span>
                    </div>
                  </div>

                  {bid.minBidLimit != null && bid.maxBidLimit != null && bid.maxBidLimit > bid.minBidLimit && (
                    <div className="bg-black/30 p-4 rounded-xl space-y-2 border border-white/10">
                      <div className="flex justify-between items-center text-xs">
                        <span className="font-bold text-slate-300 flex items-center gap-1.5">
                          <Sliders className="w-4 h-4 text-amber-400" /> Teklif Fiyatınızı Simüle Edin:
                        </span>
                        <span className="font-black text-sm text-emerald-400">{tl(customBid ?? bid.recommendedBid)}</span>
                      </div>
                      <input
                        type="range"
                        min={bid.minBidLimit}
                        max={bid.maxBidLimit}
                        step={Math.max(1, Math.round((bid.maxBidLimit - bid.minBidLimit) / 200))}
                        value={customBid ?? bid.recommendedBid ?? bid.minBidLimit}
                        onChange={(e) => setCustomBid(Number(e.target.value))}
                        className="w-full accent-emerald-500 cursor-pointer h-2 bg-slate-800 rounded-lg"
                      />
                      <div className="flex justify-between text-[10px] text-slate-400 font-medium">
                        <span>Min: {tl(bid.minBidLimit)}</span>
                        <span className="text-amber-300 font-bold">Önerilen: {tl(bid.recommendedBid)}</span>
                        <span>Maks: {tl(bid.maxBidLimit)}</span>
                      </div>
                    </div>
                  )}
                  {bid.notes && <p className="text-[11px] text-slate-400 leading-relaxed">{bid.notes}</p>}
                </div>
              )}

              <div className="grid grid-cols-1 md:grid-cols-2 gap-6">
                <div className="bg-white p-5 rounded-2xl border border-slate-200 shadow-xs space-y-3">
                  <h4 className="font-extrabold text-sm text-slate-900 flex items-center gap-2 border-b border-slate-100 pb-2">
                    <CheckCircle2 className="w-4 h-4 text-emerald-600" /> Yeterlik Kriterleri & Zorunlu Belgeler
                  </h4>
                  <ul className="space-y-2 text-xs text-slate-700">
                    {(results.qualificationCriteria || []).length === 0 && (
                      <li className="text-slate-400">Belgede yeterlik kriteri tespit edilemedi.</li>
                    )}
                    {(results.qualificationCriteria || []).map((item, idx) => (
                      <li key={idx} className="flex items-start gap-2 bg-slate-50 p-2.5 rounded-lg border border-slate-200 font-medium">
                        <span className="w-2 h-2 rounded-full bg-emerald-600 mt-1.5 shrink-0"></span>
                        <span>{item}</span>
                      </li>
                    ))}
                  </ul>
                  {(results.criticalRequirements || []).length > 0 && (
                    <>
                      <h4 className="font-extrabold text-xs text-slate-900 pt-2 border-t border-slate-100">Kritik Şartlar</h4>
                      <ul className="space-y-1.5 text-xs text-slate-700">
                        {results.criticalRequirements.map((item, idx) => (
                          <li key={idx} className="flex items-start gap-2">
                            <span className="w-1.5 h-1.5 rounded-full bg-blue-600 mt-1.5 shrink-0"></span>
                            <span>{item}</span>
                          </li>
                        ))}
                      </ul>
                    </>
                  )}
                </div>

                <div className="bg-white p-5 rounded-2xl border border-slate-200 shadow-xs space-y-3">
                  <h4 className="font-extrabold text-sm text-slate-900 flex items-center gap-2 border-b border-slate-100 pb-2">
                    <AlertTriangle className="w-4 h-4 text-rose-600" /> Riskler & Cezai Hükümler
                  </h4>
                  <div className="space-y-2 text-xs">
                    {(results.risksAndPenalties || []).length === 0 && (
                      <p className="text-slate-400">Belgede cezai hüküm/risk tespit edilemedi.</p>
                    )}
                    {(results.risksAndPenalties || []).map((risk, idx) => (
                      <div key={idx} className="p-3 bg-slate-50 rounded-lg border border-slate-200 space-y-1">
                        <div className="flex items-center justify-between gap-2">
                          <span className="font-bold text-slate-900">{risk.clause || '—'}</span>
                          <span className={`text-[10px] font-extrabold px-2 py-0.5 rounded shrink-0 ${
                            risk.level === 'Yüksek' ? 'bg-red-100 text-red-800' :
                            risk.level === 'Orta' ? 'bg-amber-100 text-amber-800' : 'bg-slate-200 text-slate-800'
                          }`}>
                            {risk.level || 'Bilgi'} Risk
                          </span>
                        </div>
                        <p className="text-slate-600 leading-snug">{risk.text}</p>
                      </div>
                    ))}
                  </div>
                </div>
              </div>

              <p className="text-[10px] text-slate-400 text-center leading-relaxed">
                Analiz yapay zeka tarafından üretilmiştir; teklif kararı öncesi şartnamenin aslını doğrulayın.
              </p>
            </div>
          )}

        </div>

        <div className="bg-slate-50 p-4 border-t border-slate-200 flex justify-end">
          <button
            onClick={() => setIsAiSpecAnalyzerOpen(false)}
            className="bg-slate-800 hover:bg-slate-700 text-white font-bold text-xs px-6 py-2.5 rounded-xl transition-colors"
          >
            Kapat
          </button>
        </div>

      </div>
    </div>
  );
};