import { logger } from '../utils/logger';
import db from '../config/database';

export interface DisputeEvent {
  tenantId: string;
  orderId: string;
  externalDisputeId: string;
  reason: string;
  customerMessage: string;
  evidenceUrls: string[];
}

/**
 * [BIZ_AUTO_05] AI 自动化售后争议处理服务
 * @description 基于历史判责数据与规则，自动生成申诉材料或执行退款决策
 */
export class DisputeResolverService {
  private static readonly DISPUTE_TABLE = 'cf_disputes';

  /**
   * 初始化表
   */
  static async initTable(): Promise<void> {
    const hasTable = await db.schema.hasTable(this.DISPUTE_TABLE);
    if (!hasTable) {
      console.log(`📦 Creating ${this.DISPUTE_TABLE} table...`);
      await db.schema.createTable(this.DISPUTE_TABLE, (table) => {
        table.increments('id').primary();
        table.string('tenant_id', 64).notNullable();
        table.string('order_id', 64).notNullable();
        table.string('external_dispute_id', 128).unique();
        table.string('reason', 255);
        table.string('status', 32).defaultTo('PENDING_AI'); // PENDING_AI, AI_RESPONDED, MANUAL_REVIEW, CLOSED
        table.text('ai_response');
        table.timestamps(true, true);
        table.index(['tenant_id', 'status']);
      });
      console.log(`✅ Table ${this.DISPUTE_TABLE} created`);
    }
  }

  /**
   * 处理新争议 (BIZ_AUTO_05)
   */
  static async processDispute(event: DisputeEvent): Promise<void> {
    logger.info(`[DisputeResolver] Processing dispute ${event.externalDisputeId} for Order: ${event.orderId}`);

    // 1. 记录争议
    await db(this.DISPUTE_TABLE).insert({
      tenant_id: event.tenantId,
      order_id: event.orderId,
      external_dispute_id: event.externalDisputeId,
      reason: event.reason,
      status: 'PENDING_AI',
      created_at: new Date(),
      updated_at: new Date()
    });

    // 2. AI 判责逻辑 (BIZ_AUTO_05)
    // 简单规则：如果是“未收到货”且物流已妥投，自动提交签收证明
    const aiResponse = await this.analyzeAndRespond(event);

    // 3. 更新状态
    await db(this.DISPUTE_TABLE).where({ external_dispute_id: event.externalDisputeId }).update({
      ai_response: aiResponse,
      status: 'AI_RESPONDED',
      updated_at: new Date()
    });
  }

  /**
   * [BIZ_AI_16-EXT] 主动发起纠纷 (由 AGI 建议触发)
   */
  static async initiateDispute(tenantId: string, orderId: string, reason: string): Promise<string> {
    const externalDisputeId = `EXT-DISP-${Date.now()}`;
    logger.info(`[DisputeResolver] Initiating dispute for Order: ${orderId}, Reason: ${reason}`);

    await db(this.DISPUTE_TABLE).insert({
      tenant_id: tenantId,
      order_id: orderId,
      external_dispute_id: externalDisputeId,
      reason: reason,
      status: 'PENDING_AI',
      created_at: new Date(),
      updated_at: new Date()
    });

    return externalDisputeId;
  }

  private static async analyzeAndRespond(event: DisputeEvent): Promise<string> {
    // 模拟 AI 分析
    if (event.reason.includes('not received')) {
      return "Logistics record shows DELIVERED on 2026-03-10. Attaching delivery proof.";
    }
    return "Product matches description. Customer provided no clear evidence of defect. Requesting more details.";
  }
}