import React, { useState } from 'react';
import { View, Text, ScrollView, StyleSheet } from 'react-native';
import { useSafeAreaInsets } from 'react-native-safe-area-context';
import { Colors, Fonts, FontSize, BorderRadius, Spacing } from '@/constants/theme';
import { formatPrice, formatPercent, formatCurrency } from '@/utils/format';
import SegmentedControl from '@/components/SegmentedControl';
import AnimatedCard from '@/components/AnimatedCard';
import PillBadge from '@/components/PillBadge';
import { useTradingData } from '@/providers/TradingDataProvider';
import { buildHistoryMetrics } from '@/lib/tradingViewModels';

const FILTERS = ['All', 'Today', 'This Week', 'This Month'];

export default function HistoryScreen() {
  const insets = useSafeAreaInsets();
  const { botState } = useTradingData();
  const tradeHistory = botState?.history || [];
  const profileOptions = ['All', ...Array.from(new Set(tradeHistory.map((trade) => trade.profileName || 'Trading Profile')))];
  const [profileIndex, setProfileIndex] = useState(0);
  const [filterIndex, setFilterIndex] = useState(0);
  const historyMetrics = buildHistoryMetrics(tradeHistory);

  const filteredTrades = profileIndex === 0
    ? tradeHistory
    : tradeHistory.filter((trade) => (trade.profileName || 'Trading Profile') === profileOptions[profileIndex]);

  const timeFilteredTrades = filteredTrades.filter((trade) => {
    if (filterIndex === 0) return true;
    const ageMs = Date.now() - Number(trade.timestamp || 0);
    if (filterIndex === 1) return ageMs <= 24 * 60 * 60 * 1000;
    if (filterIndex === 2) return ageMs <= 7 * 24 * 60 * 60 * 1000;
    return ageMs <= 30 * 24 * 60 * 60 * 1000;
  });

  return (
    <View style={[styles.container, { paddingTop: insets.top }]}>
      <View style={styles.headerSection}>
        <Text style={styles.subtitle}>COMPLETE TRADE LEDGER</Text>
        <Text style={styles.pageTitle}>Audit Logs</Text>
      </View>

      <ScrollView
        style={styles.scroll}
        contentContainerStyle={styles.content}
        showsVerticalScrollIndicator={false}
      >
        <SegmentedControl
          segments={profileOptions}
          activeIndex={profileIndex}
          onPress={setProfileIndex}
        />

        <ScrollView horizontal showsHorizontalScrollIndicator={false} contentContainerStyle={styles.metricsRow}>
          <MetricCard label="TOTAL TRADES" value={historyMetrics.totalTrades.toString()} />
          <MetricCard label="WIN RATE" value={`${historyMetrics.winRate.toFixed(1)}%`} color={Colors.accent.green} />
          <MetricCard label="NET P&L" value={`${historyMetrics.netPnl >= 0 ? '+' : '-'}$${Math.abs(historyMetrics.netPnl).toFixed(2)}`} color={historyMetrics.netPnl >= 0 ? Colors.accent.green : Colors.accent.red} mono />
        </ScrollView>

        <View style={styles.filterRow}>
          {FILTERS.map((f, i) => (
            <PressableFilter
              key={f}
              label={f}
              active={filterIndex === i}
              onPress={() => setFilterIndex(i)}
            />
          ))}
        </View>

        {timeFilteredTrades.length === 0 ? (
          <View style={styles.emptyState}>
            <Text style={styles.emptyText}>No trades found</Text>
            <Text style={styles.emptyHint}>Closed trades will appear here once the bot exits a position.</Text>
          </View>
        ) : timeFilteredTrades.map((trade, index) => (
          <TradeRow key={`${trade.symbol}-${trade.timestamp}-${index}`} trade={trade} index={index} />
        ))}
      </ScrollView>
    </View>
  );
}

function MetricCard({ label, value, color, mono }: { label: string; value: string; color?: string; mono?: boolean }) {
  return (
    <View style={styles.metricCard}>
      <Text style={styles.metricLabel}>{label}</Text>
      <Text style={[styles.metricValue, color ? { color } : null, mono ? { fontFamily: Fonts.mono.extraBold } : null]}>
        {value}
      </Text>
    </View>
  );
}

function PressableFilter({ label, active, onPress }: { label: string; active: boolean; onPress: () => void }) {
  return (
    <View style={[styles.filterPill, active && styles.filterActive]}>
      <Text
        style={[styles.filterText, active && styles.filterTextActive]}
        onPress={onPress}
      >
        {label}
      </Text>
    </View>
  );
}

function TradeRow({ trade, index }: { trade: {
  symbol: string;
  side: string;
  entryPrice: number;
  exitPrice: number;
  size: number;
  pnl: number;
  pnlPercent: number;
  reason: string;
  source?: 'BOT' | 'MANUAL';
  timestamp: number;
}; index: number }) {
  const isLoss = trade.pnl < 0;
  const pnlColor = isLoss ? Colors.accent.red : Colors.accent.green;

  const reasonColors: Record<string, { bg: string; color: string }> = {
    'Take Profit': { bg: 'rgba(0,255,136,0.1)', color: Colors.accent.green },
    'Stop Loss': { bg: 'rgba(255,51,102,0.1)', color: Colors.accent.red },
    'Signal Exit': { bg: 'rgba(52,152,219,0.1)', color: Colors.accent.blue },
    'Manual': { bg: 'rgba(255,255,255,0.05)', color: Colors.text.secondary },
  };
  const rc = reasonColors[trade.reason] || reasonColors['Manual'];

  return (
    <AnimatedCard index={index} style={[styles.tradeCard, isLoss ? styles.tradeCardLoss : undefined]}>
      {isLoss && <View style={styles.lossLeftBorder} />}
      <View style={styles.tradeContent}>
        <View style={styles.tradeHeader}>
          <Text style={styles.tradeSymbol}>{trade.symbol}</Text>
          <PillBadge
            label={trade.side}
            color={trade.side === 'BUY' ? Colors.accent.green : Colors.accent.red}
            bgColor={trade.side === 'BUY' ? 'rgba(0,255,136,0.15)' : 'rgba(255,51,102,0.15)'}
          />
          <Text style={[styles.tradePnl, { color: pnlColor }]}>
            {formatCurrency(trade.pnl)} ({formatPercent(trade.pnlPercent)})
          </Text>
        </View>

        <View style={styles.tradeDetails}>
          <Text style={styles.tradeArrow}>
            {formatPrice(trade.entryPrice)} → {formatPrice(trade.exitPrice)}
          </Text>
          <Text style={styles.tradeSize}>{trade.size} {trade.symbol.split('/')[0]}</Text>
        </View>

        <View style={styles.tradeFooter}>
          <PillBadge label={trade.reason} color={rc.color} bgColor={rc.bg} />
          <PillBadge
            label={trade.source || 'BOT'}
            color={(trade.source || 'BOT') === 'BOT' ? Colors.accent.purple : Colors.accent.orange}
            bgColor={(trade.source || 'BOT') === 'BOT' ? 'rgba(168,85,247,0.15)' : 'rgba(230,126,34,0.15)'}
          />
          <Text style={styles.tradeTime}>{new Date(trade.timestamp).toLocaleString()}</Text>
        </View>
      </View>
    </AnimatedCard>
  );
}

const styles = StyleSheet.create({
  container: {
    flex: 1,
    backgroundColor: Colors.background.primary,
  },
  headerSection: {
    padding: Spacing.screenPadding,
    paddingBottom: 0,
  },
  subtitle: {
    fontFamily: Fonts.inter.black,
    fontSize: FontSize.micro,
    color: Colors.accent.green,
    letterSpacing: 4,
    marginBottom: 8,
  },
  pageTitle: {
    fontFamily: Fonts.inter.black,
    fontSize: FontSize.hero,
    color: Colors.text.primary,
    letterSpacing: -0.5,
    marginBottom: 16,
  },
  scroll: {
    flex: 1,
  },
  content: {
    padding: Spacing.screenPadding,
    gap: 16,
    paddingBottom: 120,
  },
  metricsRow: {
    gap: 12,
  },
  metricCard: {
    backgroundColor: Colors.background.subtle,
    borderRadius: BorderRadius.large,
    borderWidth: 1,
    borderColor: Colors.border.default,
    padding: 20,
    minWidth: 140,
  },
  metricLabel: {
    fontFamily: Fonts.inter.black,
    fontSize: FontSize.micro,
    color: Colors.text.secondary,
    letterSpacing: 3,
    marginBottom: 8,
  },
  metricValue: {
    fontFamily: Fonts.inter.black,
    fontSize: FontSize.hero,
    color: Colors.text.primary,
  },
  filterRow: {
    flexDirection: 'row',
    gap: 8,
  },
  filterPill: {
    paddingHorizontal: 14,
    paddingVertical: 7,
    borderRadius: BorderRadius.xs,
    borderWidth: 1,
    borderColor: Colors.border.medium,
    backgroundColor: 'rgba(255,255,255,0.03)',
  },
  filterActive: {
    borderColor: 'rgba(0,255,136,0.45)',
    backgroundColor: 'rgba(0,255,136,0.08)',
  },
  filterText: {
    fontFamily: Fonts.inter.semiBold,
    fontSize: FontSize.badge,
    color: '#a1a1aa',
  },
  filterTextActive: {
    color: Colors.accent.green,
  },
  tradeCard: {
    backgroundColor: Colors.background.card,
    borderRadius: BorderRadius.medium,
    borderWidth: 1,
    borderColor: Colors.border.default,
    overflow: 'hidden',
    flexDirection: 'row',
  },
  tradeCardLoss: {
    backgroundColor: 'rgba(255,51,102,0.04)',
  },
  lossLeftBorder: {
    width: 2,
    backgroundColor: Colors.accent.red,
  },
  tradeContent: {
    flex: 1,
    padding: 16,
    gap: 8,
  },
  tradeHeader: {
    flexDirection: 'row',
    alignItems: 'center',
    gap: 8,
  },
  tradeSymbol: {
    fontFamily: Fonts.inter.extraBold,
    fontSize: FontSize.bodyLarge,
    color: Colors.text.primary,
  },
  tradePnl: {
    fontFamily: Fonts.mono.extraBold,
    fontSize: FontSize.body,
    marginLeft: 'auto',
  },
  tradeDetails: {
    flexDirection: 'row',
    justifyContent: 'space-between',
    alignItems: 'center',
  },
  tradeArrow: {
    fontFamily: Fonts.mono.medium,
    fontSize: FontSize.body,
    color: Colors.text.primary,
  },
  tradeSize: {
    fontFamily: Fonts.mono.regular,
    fontSize: FontSize.bodySmall,
    color: Colors.text.secondary,
  },
  tradeFooter: {
    flexDirection: 'row',
    alignItems: 'center',
    gap: 8,
    marginTop: 4,
  },
  tradeTime: {
    fontFamily: Fonts.inter.medium,
    fontSize: FontSize.micro,
    color: Colors.text.secondary,
    marginLeft: 'auto',
  },
  emptyState: {
    alignItems: 'center' as const,
    justifyContent: 'center' as const,
    paddingVertical: 60,
    gap: 10,
  },
  emptyText: {
    fontFamily: Fonts.inter.bold,
    fontSize: FontSize.subheading,
    color: Colors.text.secondary,
  },
  emptyHint: {
    fontFamily: Fonts.inter.medium,
    fontSize: FontSize.body,
    color: Colors.text.muted,
    textAlign: 'center' as const,
    maxWidth: 260,
    lineHeight: 20,
  },
});