'use client';

import { useState, useEffect } from 'react';
import { Card, CardContent, CardDescription, CardHeader, CardTitle } from '@/components/ui/card';
import { Badge } from '@/components/ui/badge';
import { Button } from '@/components/ui/button';
import { RefreshCw, TrendingUp, TrendingDown, Activity, Brain, DollarSign, Target } from 'lucide-react';

export default function AILearningDashboard() {
  const [analytics, setAnalytics] = useState(null);
  const [loading, setLoading] = useState(true);
  const [refreshing, setRefreshing] = useState(false);
  const [error, setError] = useState(null);

  const fetchAnalytics = async () => {
    try {
      const response = await fetch('/api/ai-analytics');
      if (!response.ok) throw new Error('Failed to fetch analytics');
      const data = await response.json();
      setAnalytics(data);
      setError(null);
    } catch (err) {
      setError(err.message);
    } finally {
      setLoading(false);
      setRefreshing(false);
    }
  };

  const handleRefresh = async () => {
    setRefreshing(true);
    await fetchAnalytics();
  };

  useEffect(() => {
    fetchAnalytics();
    const interval = setInterval(fetchAnalytics, 30000);
    return () => clearInterval(interval);
  }, []);

  if (loading) {
    return (
      <div className="flex items-center justify-center p-8">
        <div className="animate-spin rounded-full h-8 w-8 border-b-2 border-blue-600"></div>
        <span className="ml-2">Loading AI analytics...</span>
      </div>
    );
  }

  if (error) {
    return (
      <div className="p-4 bg-red-50 border border-red-200 rounded-lg">
        <p className="text-red-600">Error loading analytics: {error}</p>
        <Button onClick={handleRefresh} className="mt-2" size="sm">
          Try Again
        </Button>
      </div>
    );
  }

  if (!analytics) return null;

  const { overview, improvements, pnl, currentPosition, realTimeMetrics, learningProof } = analytics;

  const getTrendIcon = (trend) => {
    switch (trend) {
      case 'IMPROVING': return <TrendingUp className=\"h-4 w-4 text-green-500\" />;
      case 'DECLINING': return <TrendingDown className=\"h-4 w-4 text-red-500\" />;
      default: return <Activity className=\"h-4 w-4 text-yellow-500\" />;
    }
  };

  const getTrendColor = (trend) => {
    switch (trend) {
      case 'IMPROVING': return 'bg-green-100 text-green-800';
      case 'DECLINING': return 'bg-red-100 text-red-800';
      default: return 'bg-yellow-100 text-yellow-800';
    }
  };

  const formatCurrency = (value) => {
    return new Intl.NumberFormat('en-US', {
      style: 'currency',
      currency: 'USD',
      minimumFractionDigits: 2,
      maximumFractionDigits: 4
    }).format(value);
  };

  const formatPercentage = (value) => {
    return `${value > 0 ? '+' : ''}${value.toFixed(2)}%`;
  };

  return (
    <div className=\"space-y-6\">
      {/* Header */}
      <div className=\"flex items-center justify-between\">
        <div>
          <h2 className=\"text-2xl font-bold text-gray-900 flex items-center gap-2\">
            <Brain className=\"h-6 w-6 text-blue-600\" />
            AI Learning Analytics
          </h2>
          <p className=\"text-gray-600\">
            Proof of AI improvement and trading performance since {new Date(analytics.period.start).toLocaleDateString()}
          </p>
        </div>
        <Button 
          onClick={handleRefresh} 
          disabled={refreshing}
          variant=\"outline\"
          size=\"sm\"
        >
          <RefreshCw className={`h-4 w-4 mr-2 ${refreshing ? 'animate-spin' : ''}`} />
          Refresh
        </Button>
      </div>

      {/* Overview Stats */}
      <div className=\"grid grid-cols-1 md:grid-cols-4 gap-4\">
        <Card>
          <CardHeader className=\"flex flex-row items-center justify-between space-y-0 pb-2\">
            <CardTitle className=\"text-sm font-medium\">Learning Records</CardTitle>
            <Brain className=\"h-4 w-4 text-muted-foreground\" />
          </CardHeader>
          <CardContent>
            <div className=\"text-2xl font-bold\">{overview.totalLearningRecords.toLocaleString()}</div>
            <p className=\"text-xs text-muted-foreground\">
              {realTimeMetrics.learningRecordsPerDay}/day average
            </p>
          </CardContent>
        </Card>

        <Card>
          <CardHeader className=\"flex flex-row items-center justify-between space-y-0 pb-2\">
            <CardTitle className=\"text-sm font-medium\">AI Trades</CardTitle>
            <Activity className=\"h-4 w-4 text-muted-foreground\" />
          </CardHeader>
          <CardContent>
            <div className=\"text-2xl font-bold\">{overview.totalTrades}</div>
            <p className=\"text-xs text-muted-foreground\">
              {realTimeMetrics.tradesPerDay}/day average
            </p>
          </CardContent>
        </Card>

        <Card>
          <CardHeader className=\"flex flex-row items-center justify-between space-y-0 pb-2\">
            <CardTitle className=\"text-sm font-medium\">Active Sessions</CardTitle>
            <Target className=\"h-4 w-4 text-muted-foreground\" />
          </CardHeader>
          <CardContent>
            <div className=\"text-2xl font-bold\">{overview.activeSessions}</div>
            <p className=\"text-xs text-muted-foreground\">
              of {overview.totalSessions} total sessions
            </p>
          </CardContent>
        </Card>

        <Card>
          <CardHeader className=\"flex flex-row items-center justify-between space-y-0 pb-2\">
            <CardTitle className=\"text-sm font-medium\">Days Active</CardTitle>
            <Activity className=\"h-4 w-4 text-muted-foreground\" />
          </CardHeader>
          <CardContent>
            <div className=\"text-2xl font-bold\">{realTimeMetrics.daysSinceAIStarted}</div>
            <p className=\"text-xs text-muted-foreground\">
              Since AI trading began
            </p>
          </CardContent>
        </Card>
      </div>

      {/* Learning Improvements */}
      <Card>
        <CardHeader>
          <CardTitle className=\"flex items-center gap-2\">
            <Brain className=\"h-5 w-5\" />
            AI Learning Improvements
          </CardTitle>
          <CardDescription>
            Statistical proof of AI learning effectiveness over time
          </CardDescription>
        </CardHeader>
        <CardContent>
          <div className=\"grid grid-cols-1 md:grid-cols-2 gap-6\">
            <div>
              <div className=\"flex items-center justify-between mb-2\">
                <span className=\"text-sm font-medium\">Confidence Trend</span>
                <Badge className={getTrendColor(improvements.trend)}>
                  {getTrendIcon(improvements.trend)}
                  <span className=\"ml-1\">{improvements.trend}</span>
                </Badge>
              </div>
              <div className=\"text-2xl font-bold\">
                {formatPercentage(improvements.confidenceImprovement)}
              </div>
              <div className=\"text-xs text-muted-foreground mt-1\">
                Early: {improvements.earlyPeriod.avgConfidence}% → Recent: {improvements.recentPeriod.avgConfidence}%
              </div>
            </div>

            <div>
              <div className=\"flex items-center justify-between mb-2\">
                <span className=\"text-sm font-medium\">Sample Size</span>
                <Badge variant={learningProof.isStatisticallySignificant ? 'default' : 'secondary'}>
                  {learningProof.isStatisticallySignificant ? 'Significant' : 'Building'}
                </Badge>
              </div>
              <div className=\"text-2xl font-bold\">{learningProof.sampleSize}</div>
              <div className=\"text-xs text-muted-foreground mt-1\">
                {improvements.earlyPeriod.samples} early + {improvements.recentPeriod.samples} recent samples
              </div>
            </div>
          </div>

          {learningProof.isStatisticallySignificant && (
            <div className=\"mt-4 p-3 bg-blue-50 border border-blue-200 rounded-lg\">
              <div className=\"flex items-center gap-2 text-blue-800\">
                <Brain className=\"h-4 w-4\" />
                <span className=\"font-medium\">Learning Status:</span>
                {learningProof.hasImprovement ? 
                  'AI is demonstrably improving over time!' : 
                  'AI is learning and adapting to market conditions'}
              </div>
            </div>
          )}
        </CardContent>
      </Card>

      {/* PnL Analysis */}
      <Card>
        <CardHeader>
          <CardTitle className=\"flex items-center gap-2\">
            <DollarSign className=\"h-5 w-5\" />
            Total PnL Since AI Started
          </CardTitle>
          <CardDescription>
            Complete trading performance analysis since AI automation began
          </CardDescription>
        </CardHeader>
        <CardContent>
          <div className=\"grid grid-cols-1 md:grid-cols-3 gap-6\">
            <div className=\"text-center\">
              <div className=\"text-3xl font-bold text-blue-600\">
                {formatCurrency(pnl.totalPnL)}
              </div>
              <div className=\"text-sm text-muted-foreground\">Total PnL</div>
              <div className=\"text-xs text-green-600 mt-1\">
                {formatPercentage(pnl.totalPnLPercent)} overall
              </div>
            </div>

            <div className=\"text-center\">
              <div className=\"text-3xl font-bold text-green-600\">
                {pnl.winRate.toFixed(1)}%
              </div>
              <div className=\"text-sm text-muted-foreground\">Win Rate</div>
              <div className=\"text-xs text-muted-foreground mt-1\">
                {pnl.winningTrades}W / {pnl.losingTrades}L / {pnl.breakEvenTrades}BE
              </div>
            </div>

            <div className=\"text-center\">
              <div className=\"text-3xl font-bold text-purple-600\">
                {formatCurrency(pnl.avgTradeSize)}
              </div>
              <div className=\"text-sm text-muted-foreground\">Avg Trade Size</div>
              <div className=\"text-xs text-muted-foreground mt-1\">
                {pnl.totalTrades} total trades
              </div>
            </div>
          </div>

          {pnl.totalTrades > 0 && (
            <div className=\"mt-6 grid grid-cols-1 md:grid-cols-2 gap-4 pt-4 border-t\">
              <div>
                <div className=\"text-sm font-medium mb-1\">Average Win</div>
                <div className=\"text-lg font-bold text-green-600\">{formatCurrency(pnl.avgWin)}</div>
              </div>
              <div>
                <div className=\"text-sm font-medium mb-1\">Average Loss</div>
                <div className=\"text-lg font-bold text-red-600\">{formatCurrency(pnl.avgLoss)}</div>
              </div>
            </div>
          )}
        </CardContent>
      </Card>

      {/* Current Position */}
      {currentPosition && currentPosition.hasPosition && (
        <Card>
          <CardHeader>
            <CardTitle className=\"flex items-center gap-2\">
              <Activity className=\"h-5 w-5\" />
              Current AI Position
            </CardTitle>
            <CardDescription>
              Live position being managed by AI risk system
            </CardDescription>
          </CardHeader>
          <CardContent>
            <div className=\"grid grid-cols-1 md:grid-cols-4 gap-4\">
              <div>
                <div className=\"text-sm font-medium\">Symbol</div>
                <div className=\"text-lg font-bold\">{currentPosition.symbol}</div>
                <Badge variant=\"outline\">{currentPosition.side.toUpperCase()}</Badge>
              </div>
              <div>
                <div className=\"text-sm font-medium\">Size</div>
                <div className=\"text-lg font-bold\">{currentPosition.size}</div>
              </div>
              <div>
                <div className=\"text-sm font-medium\">Unrealized PnL</div>
                <div className={`text-lg font-bold ${currentPosition.unrealizedPnl >= 0 ? 'text-green-600' : 'text-red-600'}`}>
                  {formatCurrency(currentPosition.unrealizedPnl)}
                </div>
              </div>
              <div>
                <div className=\"text-sm font-medium\">Risk Level</div>
                <Badge className={
                  currentPosition.riskLevel === 'LOW' ? 'bg-green-100 text-green-800' :
                  currentPosition.riskLevel === 'MEDIUM' ? 'bg-yellow-100 text-yellow-800' :
                  'bg-red-100 text-red-800'
                }>
                  {currentPosition.riskLevel}
                </Badge>
                <div className=\"text-xs text-muted-foreground mt-1\">
                  {currentPosition.distanceFromStopLoss}% from SL
                </div>
              </div>
            </div>
          </CardContent>
        </Card>
      )}

      {/* Footer */}
      <div className=\"text-center text-xs text-muted-foreground\">
        Last updated: {new Date(analytics.generated).toLocaleString()}
        • Auto-refreshes every 30 seconds
      </div>
    </div>
  );
}