import {
  McpToolProvider,
  McpToolDefinition,
  McpToolHandler,
  McpContext,
} from '../interfaces';

/**
 * Sales Tools Service
 * Provides MCP tools for sales management and reporting.
 * Used by: ADMIN, SUPERVISOR, OPERATOR roles
 */
export class SalesToolsService implements McpToolProvider {
  getTools(): McpToolDefinition[] {
    return [
      {
        name: 'get_sales_summary',
        description: 'Obtiene resumen de ventas del dia, semana o mes',
        category: 'sales',
        parameters: {
          type: 'object',
          properties: {
            period: {
              type: 'string',
              enum: ['today', 'week', 'month', 'year'],
              description: 'Periodo del resumen',
              default: 'today',
            },
            branch_id: {
              type: 'string',
              format: 'uuid',
              description: 'Filtrar por sucursal (opcional)',
            },
          },
        },
        returns: {
          type: 'object',
          properties: {
            total_sales: { type: 'number' },
            transaction_count: { type: 'number' },
            average_ticket: { type: 'number' },
          },
        },
      },
      {
        name: 'get_sales_report',
        description: 'Genera reporte detallado de ventas por rango de fechas',
        category: 'sales',
        parameters: {
          type: 'object',
          properties: {
            start_date: {
              type: 'string',
              format: 'date',
              description: 'Fecha inicial (YYYY-MM-DD)',
            },
            end_date: {
              type: 'string',
              format: 'date',
              description: 'Fecha final (YYYY-MM-DD)',
            },
            group_by: {
              type: 'string',
              enum: ['day', 'week', 'month', 'branch', 'category', 'seller'],
              description: 'Agrupar resultados por',
              default: 'day',
            },
            branch_id: {
              type: 'string',
              format: 'uuid',
              description: 'Filtrar por sucursal',
            },
          },
          required: ['start_date', 'end_date'],
        },
        returns: { type: 'array', items: { type: 'object' } },
      },
      {
        name: 'get_top_products',
        description: 'Obtiene los productos mas vendidos',
        category: 'sales',
        parameters: {
          type: 'object',
          properties: {
            period: {
              type: 'string',
              enum: ['today', 'week', 'month', 'year'],
              default: 'month',
            },
            limit: { type: 'number', default: 10 },
            branch_id: { type: 'string', format: 'uuid' },
          },
        },
        returns: { type: 'array', items: { type: 'object' } },
      },
      {
        name: 'get_top_customers',
        description: 'Obtiene los clientes con mas compras',
        category: 'sales',
        parameters: {
          type: 'object',
          properties: {
            period: {
              type: 'string',
              enum: ['month', 'quarter', 'year'],
              default: 'month',
            },
            limit: { type: 'number', default: 10 },
            order_by: {
              type: 'string',
              enum: ['amount', 'transactions'],
              default: 'amount',
            },
          },
        },
        returns: { type: 'array', items: { type: 'object' } },
      },
      {
        name: 'get_sales_by_branch',
        description: 'Compara ventas entre sucursales',
        category: 'sales',
        parameters: {
          type: 'object',
          properties: {
            period: {
              type: 'string',
              enum: ['today', 'week', 'month'],
              default: 'today',
            },
          },
        },
        returns: { type: 'array', items: { type: 'object' } },
      },
      {
        name: 'get_my_sales',
        description: 'Obtiene las ventas del usuario actual (operador)',
        category: 'sales',
        parameters: {
          type: 'object',
          properties: {
            period: {
              type: 'string',
              enum: ['today', 'week', 'month'],
              default: 'today',
            },
          },
        },
        returns: {
          type: 'object',
          properties: {
            total: { type: 'number' },
            count: { type: 'number' },
            sales: { type: 'array' },
          },
        },
      },
      {
        name: 'create_sale',
        description: 'Registra una nueva venta',
        category: 'sales',
        parameters: {
          type: 'object',
          properties: {
            items: {
              type: 'array',
              items: {
                type: 'object',
                properties: {
                  product_id: { type: 'string', format: 'uuid' },
                  quantity: { type: 'number', minimum: 1 },
                  unit_price: { type: 'number' },
                  discount: { type: 'number', default: 0 },
                },
                required: ['product_id', 'quantity'],
              },
            },
            customer_id: { type: 'string', format: 'uuid' },
            payment_method: {
              type: 'string',
              enum: ['cash', 'card', 'transfer', 'credit'],
            },
            notes: { type: 'string' },
          },
          required: ['items', 'payment_method'],
        },
        returns: {
          type: 'object',
          properties: {
            sale_id: { type: 'string' },
            total: { type: 'number' },
            status: { type: 'string' },
          },
        },
      },
    ];
  }

  getHandler(toolName: string): McpToolHandler | undefined {
    const handlers: Record<string, McpToolHandler> = {
      get_sales_summary: this.getSalesSummary.bind(this),
      get_sales_report: this.getSalesReport.bind(this),
      get_top_products: this.getTopProducts.bind(this),
      get_top_customers: this.getTopCustomers.bind(this),
      get_sales_by_branch: this.getSalesByBranch.bind(this),
      get_my_sales: this.getMySales.bind(this),
      create_sale: this.createSale.bind(this),
    };
    return handlers[toolName];
  }

  private async getSalesSummary(
    params: { period?: string; branch_id?: string },
    context: McpContext
  ): Promise<any> {
    // TODO: Connect to SalesService
    const period = params.period || 'today';
    return {
      period,
      branch_id: params.branch_id || 'all',
      total_sales: 15750.00,
      transaction_count: 42,
      average_ticket: 375.00,
      comparison: {
        previous_period: 14200.00,
        change_percent: 10.9,
      },
      message: 'Conectar a SalesService real',
    };
  }

  private async getSalesReport(
    params: { start_date: string; end_date: string; group_by?: string; branch_id?: string },
    context: McpContext
  ): Promise<any[]> {
    // TODO: Connect to SalesService
    return [
      {
        date: params.start_date,
        total: 5250.00,
        count: 15,
        avg_ticket: 350.00,
      },
      {
        date: params.end_date,
        total: 4800.00,
        count: 12,
        avg_ticket: 400.00,
      },
    ];
  }

  private async getTopProducts(
    params: { period?: string; limit?: number; branch_id?: string },
    context: McpContext
  ): Promise<any[]> {
    // TODO: Connect to SalesService
    return [
      { rank: 1, product: 'Producto A', quantity: 150, revenue: 7500.00 },
      { rank: 2, product: 'Producto B', quantity: 120, revenue: 6000.00 },
      { rank: 3, product: 'Producto C', quantity: 100, revenue: 5000.00 },
    ].slice(0, params.limit || 10);
  }

  private async getTopCustomers(
    params: { period?: string; limit?: number; order_by?: string },
    context: McpContext
  ): Promise<any[]> {
    // TODO: Connect to CustomersService
    return [
      { rank: 1, customer: 'Cliente A', total: 25000.00, transactions: 15 },
      { rank: 2, customer: 'Cliente B', total: 18000.00, transactions: 12 },
    ].slice(0, params.limit || 10);
  }

  private async getSalesByBranch(
    params: { period?: string },
    context: McpContext
  ): Promise<any[]> {
    // TODO: Connect to SalesService + BranchesService
    return [
      { branch: 'Sucursal Centro', total: 8500.00, count: 25 },
      { branch: 'Sucursal Norte', total: 7250.00, count: 17 },
    ];
  }

  private async getMySales(
    params: { period?: string },
    context: McpContext
  ): Promise<any> {
    // TODO: Connect to SalesService with context.userId
    return {
      user_id: context.userId,
      period: params.period || 'today',
      total: 3500.00,
      count: 8,
      sales: [
        { id: 'sale-1', total: 450.00, time: '10:30' },
        { id: 'sale-2', total: 680.00, time: '11:45' },
      ],
    };
  }

  private async createSale(
    params: {
      items: Array<{ product_id: string; quantity: number; unit_price?: number; discount?: number }>;
      customer_id?: string;
      payment_method: string;
      notes?: string;
    },
    context: McpContext
  ): Promise<any> {
    // TODO: Connect to SalesService
    const total = params.items.reduce((sum, item) => {
      const price = item.unit_price || 100; // Default price for demo
      const discount = item.discount || 0;
      return sum + (price * item.quantity * (1 - discount / 100));
    }, 0);

    return {
      sale_id: `SALE-${Date.now()}`,
      total,
      items_count: params.items.length,
      payment_method: params.payment_method,
      status: 'completed',
      created_by: context.userId,
      message: 'Conectar a SalesService real',
    };
  }
}