import { useState, useEffect, useMemo } from 'react';
import { useNavigate } from 'react-router-dom';
import { getAgentHistory, mapHistoryMessagesToItems, type HistoryItem } from '../lib/api';
import Icon from './Icon';

interface Props {
  locale: string;
  dashboard: { brandName: string; navHome: string; navStore: string; navDivination: string; navManual: string; navAuto: string; navHistory: string; navLanguage: string; navSettings: string; logout: string };
  history: { title: string; statTotal: string; statLatest: string; filters: string; filterAll: string; filterCareer: string; filterLove: string; filterWealth: string; noResults: string };
}

const ALL_CATEGORIES = ['career', 'love', 'wealth', 'fortune', 'dream', 'health', 'study', 'search', 'other'] as const;
type CategoryKey = typeof ALL_CATEGORIES[number];

const CATEGORY_COLORS: Record<string, string> = {
  'career': 'bg-blue-50 text-blue-500',
  'love': 'bg-pink-50 text-pink-500',
  'wealth': 'bg-amber-50 text-amber-600',
  'fortune': 'bg-purple-50 text-purple-500',
  'dream': 'bg-indigo-50 text-indigo-500',
  'health': 'bg-red-50 text-red-500',
  'study': 'bg-green-50 text-green-600',
  'search': 'bg-cyan-50 text-cyan-600',
  'other': 'bg-slate-100 text-slate-500',
};

const CATEGORY_LABELS_ZH: Record<string, string> = {
  'career': '事业',
  'love': '感情',
  'wealth': '财富',
  'fortune': '运势',
  'dream': '解梦',
  'health': '健康',
  'study': '学业',
  'search': '寻物',
  'other': '其他',
};

const CATEGORY_LABELS_EN: Record<string, string> = {
  'career': 'Career',
  'love': 'Love',
  'wealth': 'Wealth',
  'fortune': 'Fortune',
  'dream': 'Dream',
  'health': 'Health',
  'study': 'Study',
  'search': 'Search',
  'other': 'Other',
};

const RATING_COLORS: Record<string, string> = {
  '上上签': 'bg-amber-50 text-amber-500',
  '上签': 'bg-amber-50 text-amber-500',
  '中上签': 'bg-violet-50 text-violet-600',
  '中签': 'bg-slate-100 text-slate-500',
  '下签': 'bg-red-50 text-red-500',
};

export default function HistoryListPage({ locale, history: i18n }: Props) {
  const navigate = useNavigate();
  const [allItems, setAllItems] = useState<HistoryItem[]>([]);
  const [loading, setLoading] = useState(true);
  const [error, setError] = useState('');
  const [selectedId, setSelectedId] = useState<string | null>(null);
  const [activeFilter, setActiveFilter] = useState<CategoryKey | 'all'>('all');
  const [searchQuery, setSearchQuery] = useState('');

  // 获取历史数据
  useEffect(() => {
    let alive = true;
    setLoading(true);
    setError('');

    getAgentHistory()
      .then((data) => {
        if (!alive) return;
        setAllItems(mapHistoryMessagesToItems(data.messages));
      })
      .catch((err) => {
        if (!alive) return;
        setError(err instanceof Error ? err.message : 'Failed to load history');
      })
      .finally(() => {
        if (alive) setLoading(false);
      });

    return () => {
      alive = false;
    };
  }, []);

  const stats = useMemo(() => {
    const total = allItems.length;
    const latest = allItems.length > 0 ? allItems[0].created_at : null;
    return { total, latest };
  }, [allItems]);

  // 过滤后的列表
  const filteredItems = useMemo(() => {
    let items = allItems;

    // 分类筛选
    if (activeFilter !== 'all') {
      items = items.filter((item) => item.category === activeFilter);
    }

    // 搜索筛选
    if (searchQuery.trim()) {
      const query = searchQuery.toLowerCase();
      items = items.filter(
        (item) =>
          item.question.toLowerCase().includes(query) ||
          item.hexagram_name.toLowerCase().includes(query)
      );
    }

    return items;
  }, [allItems, activeFilter, searchQuery]);

  // 各分类数量
  const filterCounts = useMemo(() => {
    const counts: Record<string, number> = { all: allItems.length };
    for (const cat of ALL_CATEGORIES) {
      counts[cat] = allItems.filter((item) => item.category === cat).length;
    }
    return counts;
  }, [allItems]);

  // 格式化最近时间
  const formatLatest = (dateStr: string | null) => {
    if (!dateStr) return '--';
    const date = new Date(dateStr);
    const now = new Date();
    const isToday = date.toDateString() === now.toDateString();
    const timeStr = date.toLocaleTimeString(locale === 'en' ? 'en-US' : 'zh-CN', {
      hour: '2-digit',
      minute: '2-digit',
    });
    if (isToday) {
      return locale === 'en' ? `Today ${timeStr}` : `今天 ${timeStr}`;
    }
    return date.toLocaleDateString(locale === 'en' ? 'en-US' : 'zh-CN', {
      month: 'short',
      day: 'numeric',
    });
  };

  // 点击卡片跳转
  const handleItemClick = (item: HistoryItem) => {
    setSelectedId(item.id);
    navigate(`/${locale}/history/${item.threadId}`);
  };

  // 返回首页
  const handleBackHome = () => {
    navigate(`/${locale}/dashboard`);
  };

  return (
    <div className="flex flex-col gap-5 min-h-full">
      {/* Header */}
      <div className="flex items-center justify-between gap-4">
        <div className="flex items-center gap-3">
          <button
            onClick={handleBackHome}
            className="w-10 h-10 rounded-full bg-white border border-slate-200 flex items-center justify-center hover:bg-slate-50 transition-colors"
            aria-label={locale === 'en' ? 'Back to home' : '返回首页'}
          >
            <Icon name="arrow_back" className="w-5 h-5 text-slate-600" />
          </button>
          <div>
            <h1 className="text-slate-900 text-xl font-semibold">{i18n.title}</h1>
          </div>
        </div>
        <div className="flex items-center gap-2">
          {/* Search */}
          <div className="relative">
            <Icon name="search" className="absolute left-3 top-1/2 -translate-y-1/2 w-4 h-4 text-slate-400" />
            <input
              type="text"
              placeholder={locale === 'en' ? 'Search question or hexagram' : '搜索问题或卦名'}
              value={searchQuery}
              onChange={(e) => setSearchQuery(e.target.value)}
              className="w-60 pl-9 pr-4 py-2 rounded-full bg-white border border-slate-200 text-sm focus:outline-none focus:border-violet-400 transition-colors"
            />
          </div>
        </div>
      </div>

      {/* Error */}
      {error && (
        <div className="rounded-xl border border-red-200 bg-red-50 px-4 py-3 text-sm text-red-600">
          {error}
        </div>
      )}

      {/* Stats */}
      <div className="grid grid-cols-1 sm:grid-cols-2 gap-4">
        <div className="bg-white rounded-xl p-4 border border-slate-200 flex flex-col gap-1">
          <p className="text-slate-500 text-xs">{i18n.statTotal}</p>
          <p className="text-slate-900 text-2xl font-bold">{stats.total}</p>
        </div>
        <div className="bg-white rounded-xl p-4 border border-slate-200 flex flex-col gap-1">
          <p className="text-slate-500 text-xs">{i18n.statLatest}</p>
          <p className="text-slate-900 text-lg font-bold">{formatLatest(stats.latest)}</p>
        </div>
      </div>

      {/* Main Content: List + Filters */}
      <div className="flex flex-col lg:flex-row gap-5 flex-1 min-h-0">
        {/* List */}
        <div className="flex-1 bg-white rounded-2xl p-4 border border-slate-200 flex flex-col gap-3 overflow-y-auto">
          <div className="flex items-center justify-between">
            <h3 className="text-slate-900 text-sm font-bold">{i18n.title}</h3>
            <span className="text-slate-400 text-xs">{filteredItems.length} {locale === 'en' ? 'items' : '条'}</span>
          </div>

          {loading ? (
            <div className="text-slate-400 text-sm py-8 text-center">{locale === 'en' ? 'Loading...' : '加载中...'}</div>
          ) : filteredItems.length === 0 ? (
            <div className="text-slate-400 text-sm py-8 text-center">{i18n.noResults}</div>
          ) : (
            <div className="flex flex-col gap-2">
              {filteredItems.map((item) => (
                <button
                  key={item.id}
                  onClick={() => handleItemClick(item)}
                  className={`flex items-center gap-3 rounded-xl p-4 text-left transition-all cursor-pointer border ${
                    selectedId === item.id
                      ? 'bg-violet-50 border-violet-400'
                      : 'bg-white border-slate-200 hover:bg-slate-50'
                  }`}
                >
                  <div className="w-11 h-11 rounded-[10px] bg-blue-50 flex items-center justify-center shrink-0">
                    <Icon name="auto_awesome" className="w-5 h-5 text-blue-400" />
                  </div>
                  <div className="flex-1 min-w-0">
                    <p className="text-slate-900 text-sm font-semibold truncate">{item.question}</p>
                    <div className="flex items-center gap-2 mt-1">
                      {item.category && (
                        <span className={`px-2 py-0.5 rounded-md text-xs font-medium ${CATEGORY_COLORS[item.category] || 'bg-slate-100 text-slate-500'}`}>
                          {locale === 'en' ? (CATEGORY_LABELS_EN[item.category] || item.category) : (CATEGORY_LABELS_ZH[item.category] || item.category)}
                        </span>
                      )}
                      {item.hexagram_name && (
                        <span className="px-2 py-0.5 rounded-md bg-violet-50 text-violet-600 text-xs font-medium">{item.hexagram_name}</span>
                      )}
                      {item.rating && (
                        <span className={`px-2 py-0.5 rounded-md text-xs font-medium ${RATING_COLORS[item.rating] || 'bg-slate-100 text-slate-500'}`}>
                          {item.rating}
                        </span>
                      )}
                    </div>
                  </div>
                  <div className="flex flex-col items-end gap-1 shrink-0 w-24">
                    <span className="text-slate-400 text-xs">{item.created_at?.slice(0, 10) || ''}</span>
                    <span className="text-violet-500">
                      <Icon name="chevron_right" className="w-5 h-5" />
                    </span>
                  </div>
                </button>
              ))}
            </div>
          )}
        </div>

        {/* Side: Quick Filters */}
        <div className="w-full lg:w-[280px] flex flex-col gap-4 shrink-0">
          <div className="bg-white rounded-2xl p-4 border border-slate-200 flex flex-col gap-2">
            <h3 className="text-slate-900 text-sm font-bold">{i18n.filters}</h3>
            <button
              onClick={() => setActiveFilter('all')}
              className={`flex items-center justify-between px-3 py-2 rounded-lg text-sm transition-colors ${
                activeFilter === 'all' ? 'bg-slate-100 text-violet-600 font-semibold' : 'text-slate-500 hover:bg-slate-50'
              }`}
            >
              <span>{i18n.filterAll}</span>
              <span className={activeFilter === 'all' ? 'text-violet-500' : 'text-slate-400'}>{filterCounts.all}</span>
            </button>
            {ALL_CATEGORIES.map((cat) => (
              <button
                key={cat}
                onClick={() => setActiveFilter(cat)}
                className={`flex items-center justify-between px-3 py-2 rounded-lg text-sm transition-colors ${
                  activeFilter === cat ? 'bg-slate-100 text-violet-600 font-semibold' : 'text-slate-500 hover:bg-slate-50'
                }`}
              >
                <span>{locale === 'en' ? (CATEGORY_LABELS_EN[cat] || cat) : (CATEGORY_LABELS_ZH[cat] || cat)}</span>
                <span className={activeFilter === cat ? 'text-violet-500' : 'text-slate-400'}>{filterCounts[cat] || 0}</span>
              </button>
            ))}
          </div>
        </div>
      </div>
    </div>
  );
}