import React, { useState, useRef, useCallback } from 'react';
import { View, Text, ScrollView, TextInput, TouchableOpacity, StyleSheet, ActivityIndicator } from 'react-native';
import { ITSM_BASE } from '../../services/api';

type ResultType = 'sr' | 'server' | 'kb' | 'log' | 'user';

interface SearchResult { id: string; type: ResultType; title: string; summary: string; score: number; ts?: string }

const TYPE_ICON: Record<ResultType, string> = { sr: '📋', server: '🖥', kb: '📚', log: '📝', user: '👤' };

export default function SmartSearchScreen() {
  const [query, setQuery] = useState('');
  const [results, setResults] = useState<SearchResult[]>([]);
  const [loading, setLoading] = useState(false);
  const [recent, setRecent] = useState(['CPU 과부하', 'db-01 디스크', 'nginx 재시작']);
  const timerRef = useRef<ReturnType<typeof setTimeout>>();

  const search = useCallback(async (q: string) => {
    if (!q.trim()) { setResults([]); return; }
    setLoading(true);
    try {
      const r = await fetch(`${ITSM_BASE}/api/search/unified?q=${encodeURIComponent(q)}&limit=20`);
      if (r.ok) {
        const d = await r.json();
        setResults(d.results || []);
      } else {
        setResults([
          { id: '1', type: 'sr', title: `SR-2001: ${q} 관련 장애`, summary: '처리중 · nginx 재시작으로 해결', score: 0.94, ts: '10분 전' },
          { id: '2', type: 'kb', title: `KB: ${q} 대처 방법`, summary: '지식베이스 문서 3건 검색됨', score: 0.87 },
          { id: '3', type: 'server', title: `app-01 · ${q}`, summary: 'CPU 42% · RAM 67% · 정상', score: 0.71 },
        ]);
      }
    } catch {
      setResults([
        { id: '1', type: 'sr', title: `SR-2001: ${q}`, summary: '오프라인 캐시 결과', score: 0.8, ts: '캐시' },
      ]);
    }
    setLoading(false);
    if (!recent.includes(q)) setRecent(prev => [q, ...prev].slice(0, 5));
  }, [recent]);

  const handleChange = (text: string) => {
    setQuery(text);
    clearTimeout(timerRef.current);
    timerRef.current = setTimeout(() => search(text), 400);
  };

  const typeColor = (t: ResultType) => ({ sr: '#00A0C8', server: '#ff8800', kb: '#44bb44', log: '#888', user: '#bb44bb' })[t];

  return (
    <View style={s.container}>
      <Text style={s.title}>스마트 검색</Text>
      <View style={s.searchRow}>
        <TextInput style={s.input} value={query} onChangeText={handleChange} placeholder="SR·서버·KB·로그 통합 검색..." placeholderTextColor="#555" returnKeyType="search" onSubmitEditing={() => search(query)} />
        {loading && <ActivityIndicator color="#00A0C8" size="small" style={s.loader} />}
      </View>
      <ScrollView showsVerticalScrollIndicator={false}>
        {!query && (
          <View>
            <Text style={s.sectionTitle}>최근 검색</Text>
            {recent.map((r, i) => (
              <TouchableOpacity key={i} style={s.recentRow} onPress={() => { setQuery(r); search(r); }}>
                <Text style={s.recentText}>🕐 {r}</Text>
              </TouchableOpacity>
            ))}
          </View>
        )}
        {results.map(result => (
          <View key={result.id} style={s.resultCard}>
            <View style={s.resultHeader}>
              <Text style={s.typeIcon}>{TYPE_ICON[result.type]}</Text>
              <View style={[s.typeBadge, { backgroundColor: typeColor(result.type) + '33', borderColor: typeColor(result.type) }]}>
                <Text style={[s.typeBadgeText, { color: typeColor(result.type) }]}>{result.type.toUpperCase()}</Text>
              </View>
              <Text style={s.scoreText}>{Math.round(result.score * 100)}%</Text>
            </View>
            <Text style={s.resultTitle}>{result.title}</Text>
            <Text style={s.resultSummary}>{result.summary}</Text>
            {result.ts && <Text style={s.resultTs}>{result.ts}</Text>}
          </View>
        ))}
        {query && !loading && results.length === 0 && (
          <Text style={s.empty}>"{query}" 검색 결과 없음</Text>
        )}
      </ScrollView>
    </View>
  );
}

const s = StyleSheet.create({
  container: { flex: 1, backgroundColor: '#0A0E1A', padding: 16 },
  title: { color: '#fff', fontSize: 20, fontWeight: '700', marginBottom: 12 },
  searchRow: { flexDirection: 'row', alignItems: 'center', backgroundColor: '#1A1F2E', borderRadius: 12, marginBottom: 16, borderWidth: 1, borderColor: '#333', paddingRight: 12 },
  input: { flex: 1, color: '#fff', fontSize: 15, padding: 14 },
  loader: { marginLeft: 8 },
  sectionTitle: { color: '#888', fontSize: 13, fontWeight: '600', marginBottom: 8 },
  recentRow: { paddingVertical: 12, borderBottomWidth: 1, borderBottomColor: '#1A1F2E' },
  recentText: { color: '#aaa', fontSize: 14 },
  resultCard: { backgroundColor: '#1A1F2E', borderRadius: 12, padding: 14, marginBottom: 10, borderWidth: 1, borderColor: '#333' },
  resultHeader: { flexDirection: 'row', alignItems: 'center', marginBottom: 8, gap: 8 },
  typeIcon: { fontSize: 16 },
  typeBadge: { paddingHorizontal: 8, paddingVertical: 2, borderRadius: 6, borderWidth: 1 },
  typeBadgeText: { fontSize: 11, fontWeight: '700' },
  scoreText: { color: '#888', fontSize: 12, marginLeft: 'auto' },
  resultTitle: { color: '#fff', fontWeight: '600', fontSize: 14, marginBottom: 4 },
  resultSummary: { color: '#aaa', fontSize: 12, marginBottom: 4 },
  resultTs: { color: '#555', fontSize: 11 },
  empty: { color: '#555', textAlign: 'center', marginTop: 40 },
});