import db from '../config/database';
import { AuditService } from './AuditService';
import { AIService } from './AIService';

/**
 * [BIZ_MKT_11] 基于用户画像的个性化定价策略
 * 负责针对不同用户群体（如新客、老客、高价值客户等）自动生成个性化的定价与折扣建议
 */
export class PersonalizedPricingService {
  /**
   * 为特定用户群体生成个性化价格
   */
  static async suggestPersonalizedPrice(
    tenantId: string, 
    productId: string, 
    userSegment: string,
    traceId: string
  ): Promise<number> {
    // 1. 获取商品基础价格
    const product = await db('cf_product').where({ productId }).first();
    const basePrice = product?.price || 0;

    // 2. 个性化策略逻辑 (基于用户画像自动计算最优折扣)
    // 模拟调用 AI 分析用户画像并给出折扣建议
    const discountRate = await AIService.calculateOptimalDiscount(userSegment, productId);
    const personalizedPrice = basePrice * (1 - discountRate);

    // 3. 持久化定价记录
    await db.transaction(async (trx) => {
      const [id] = await trx('cf_personalized_pricing').insert({
        tenant_id: tenantId,
        product_id: productId,
        user_segment: userSegment,
        base_price: basePrice,
        personalized_price: personalizedPrice,
        discount_rate: discountRate
      });

      // 审计记录
      await AuditService.log({
        tenant_id: tenantId,
        action: 'PERSONALIZED_PRICE_SUGGESTED',
        target_type: 'PRICING_STRATEGY',
        target_id: id.toString(),
        trace_id: traceId,
        new_data: JSON.stringify({ personalizedPrice, discountRate }),
        metadata: JSON.stringify({ userSegment, productId })
      });
    });

    return personalizedPrice;
  }

  /**
   * 获取租户所有生效的个性化定价
   */
  static async getActivePricings(tenantId: string) {
    return await db('cf_personalized_pricing')
      .where({ tenant_id: tenantId })
      .orderBy('created_at', 'desc');
  }
}
