import { Injectable } from '@nestjs/common';
import { PrismaService } from '../../database/prisma.service';

export interface PerformanceMetrics {
  period: string;
  sales: {
    total: number;
    change: number;
    trend: 'up' | 'down' | 'stable';
  };
  orders: {
    total: number;
    change: number;
    trend: 'up' | 'down' | 'stable';
  };
  revenue: {
    total: number;
    change: number;
    trend: 'up' | 'down' | 'stable';
  };
  customers: {
    total: number;
    newCustomers: number;
    change: number;
  };
  platforms: {
    name: string;
    sales: number;
    orders: number;
    percentage: number;
  }[];
}

@Injectable()
export class PerformanceService {
  constructor(private prisma: PrismaService) {}

  async getDashboardMetrics(tenantId: string): Promise<PerformanceMetrics> {
    // Demo veriler
    return {
      period: 'Bu Ay',
      sales: {
        total: 245890,
        change: 12.5,
        trend: 'up',
      },
      orders: {
        total: 1247,
        change: 8.3,
        trend: 'up',
      },
      revenue: {
        total: 198567,
        change: 15.2,
        trend: 'up',
      },
      customers: {
        total: 892,
        newCustomers: 45,
        change: 5.1,
      },
      platforms: [
        { name: 'Trendyol', sales: 125000, orders: 567, percentage: 45 },
        { name: 'Hepsiburada', sales: 78000, orders: 342, percentage: 30 },
        { name: 'Amazon', sales: 35000, orders: 189, percentage: 15 },
        { name: 'N11', sales: 25000, orders: 149, percentage: 10 },
      ],
    };
  }

  async getSalesAnalytics(tenantId: string, period: string = '30d') {
    // Günlük satış verileri
    const days = period === '7d' ? 7 : period === '30d' ? 30 : 90;
    const salesData: any[] = [];

    for (let i = days - 1; i >= 0; i--) {
      const date = new Date();
      date.setDate(date.getDate() - i);
      salesData.push({
        date: date.toISOString().split('T')[0],
        sales: Math.floor(Math.random() * 10000) + 5000,
        orders: Math.floor(Math.random() * 50) + 20,
        revenue: Math.floor(Math.random() * 8000) + 4000,
      });
    }

    return {
      period,
      data: salesData,
      summary: {
        totalSales: salesData.reduce((a, b) => a + b.sales, 0),
        totalOrders: salesData.reduce((a, b) => a + b.orders, 0),
        totalRevenue: salesData.reduce((a, b) => a + b.revenue, 0),
        avgOrderValue: Math.floor(
          salesData.reduce((a, b) => a + b.sales, 0) /
            salesData.reduce((a, b) => a + b.orders, 0),
        ),
      },
    };
  }

  async getProductPerformance(tenantId: string, limit: number = 10) {
    // En iyi performans gösteren ürünler
    const products = [
      {
        id: 'PRD-001',
        name: 'Samsung Galaxy S24 Ultra',
        sales: 89,
        revenue: 3861111,
        rating: 4.8,
      },
      {
        id: 'PRD-002',
        name: 'iPhone 15 Pro Max',
        sales: 67,
        revenue: 4020000,
        rating: 4.9,
      },
      {
        id: 'PRD-003',
        name: 'Apple MacBook Pro M3',
        sales: 34,
        revenue: 3060000,
        rating: 4.7,
      },
      {
        id: 'PRD-004',
        name: 'Sony WH-1000XM5',
        sales: 156,
        revenue: 936000,
        rating: 4.6,
      },
      {
        id: 'PRD-005',
        name: 'Apple AirPods Pro 2',
        sales: 234,
        revenue: 819000,
        rating: 4.8,
      },
      {
        id: 'PRD-006',
        name: 'Samsung QLED 65"',
        sales: 23,
        revenue: 1150000,
        rating: 4.5,
      },
      {
        id: 'PRD-007',
        name: 'PlayStation 5',
        sales: 45,
        revenue: 900000,
        rating: 4.7,
      },
      {
        id: 'PRD-008',
        name: 'Nintendo Switch OLED',
        sales: 78,
        revenue: 546000,
        rating: 4.6,
      },
      {
        id: 'PRD-009',
        name: 'iPad Pro 12.9',
        sales: 56,
        revenue: 1120000,
        rating: 4.8,
      },
      {
        id: 'PRD-010',
        name: 'Dyson V15 Detect',
        sales: 67,
        revenue: 670000,
        rating: 4.4,
      },
    ];

    return products.slice(0, limit);
  }

  async getCategoryPerformance(tenantId: string) {
    return [
      { category: 'Elektronik', sales: 456000, orders: 234, growth: 15.2 },
      { category: 'Moda', sales: 234000, orders: 567, growth: 8.4 },
      { category: 'Ev & Yaşam', sales: 178000, orders: 189, growth: -2.1 },
      { category: 'Kozmetik', sales: 145000, orders: 412, growth: 22.5 },
      { category: 'Spor', sales: 98000, orders: 156, growth: 5.7 },
      { category: 'Kitap & Hobi', sales: 67000, orders: 234, growth: 11.3 },
    ];
  }

  async getPlatformComparison(tenantId: string) {
    return {
      platforms: [
        {
          name: 'Trendyol',
          logo: '/images/pazaryeri/trendyol.png',
          metrics: {
            sales: 125000,
            orders: 567,
            avgOrderValue: 220,
            rating: 4.7,
            returnRate: 3.2,
            conversionRate: 12.5,
          },
          trend: { sales: 15.2, orders: 12.1 },
        },
        {
          name: 'Hepsiburada',
          logo: '/images/pazaryeri/hepsiburada.png',
          metrics: {
            sales: 78000,
            orders: 342,
            avgOrderValue: 228,
            rating: 4.5,
            returnRate: 4.1,
            conversionRate: 10.8,
          },
          trend: { sales: 8.4, orders: 6.2 },
        },
        {
          name: 'Amazon',
          logo: '/images/pazaryeri/amazon.png',
          metrics: {
            sales: 35000,
            orders: 189,
            avgOrderValue: 185,
            rating: 4.6,
            returnRate: 2.8,
            conversionRate: 14.2,
          },
          trend: { sales: 22.5, orders: 18.7 },
        },
        {
          name: 'N11',
          logo: '/images/pazaryeri/n11.png',
          metrics: {
            sales: 25000,
            orders: 149,
            avgOrderValue: 168,
            rating: 4.3,
            returnRate: 5.5,
            conversionRate: 8.9,
          },
          trend: { sales: -2.1, orders: -4.5 },
        },
      ],
    };
  }

  async getHourlyDistribution(tenantId: string) {
    // Saatlik sipariş dağılımı
    const distribution: any[] = [];
    for (let hour = 0; hour < 24; hour++) {
      // Gerçekçi dağılım: gece az, öğle ve akşam saatlerinde yoğun
      let baseValue = 10;
      if (hour >= 10 && hour <= 14) baseValue = 50;
      if (hour >= 19 && hour <= 23) baseValue = 80;
      if (hour >= 0 && hour <= 6) baseValue = 5;

      distribution.push({
        hour: `${hour.toString().padStart(2, '0')}:00`,
        orders: baseValue + Math.floor(Math.random() * 20),
      });
    }
    return distribution;
  }

  async getRealtimeStats(tenantId: string) {
    // Gerçek zamanlı istatistikler
    return {
      timestamp: new Date(),
      activeVisitors: Math.floor(Math.random() * 100) + 50,
      ordersLastHour: Math.floor(Math.random() * 20) + 5,
      revenueLastHour: Math.floor(Math.random() * 5000) + 2000,
      pendingOrders: Math.floor(Math.random() * 30) + 10,
      lowStockAlerts: Math.floor(Math.random() * 10),
      conversionRate: (Math.random() * 5 + 8).toFixed(1),
    };
  }

  async getCompetitorInsights(tenantId: string) {
    // Rakip analiz verileri
    return {
      pricePosition: {
        belowMarket: 34,
        atMarket: 45,
        aboveMarket: 21,
      },
      opportunities: [
        {
          product: 'Samsung Galaxy S24',
          currentPrice: 42999,
          competitorPrice: 44999,
          potentialProfit: 2000,
        },
        {
          product: 'iPhone 15 Pro',
          currentPrice: 59999,
          competitorPrice: 62999,
          potentialProfit: 3000,
        },
        {
          product: 'AirPods Pro 2',
          currentPrice: 6999,
          competitorPrice: 7499,
          potentialProfit: 500,
        },
      ],
      threats: [
        {
          product: 'MacBook Air M2',
          yourPrice: 42999,
          lowestPrice: 39999,
          seller: 'Rakip A',
        },
        {
          product: 'iPad Air',
          yourPrice: 24999,
          lowestPrice: 23499,
          seller: 'Rakip B',
        },
      ],
    };
  }
}