import { Injectable, Inject } from '@nestjs/common';
import { QueryRunner, DataSource } from 'typeorm';
import { DATA_SOURCE } from '../core/constants';
import { RedisClientToken } from '../core/configs/cache/redis-client.adapter.provider';
import { IRedisClient } from '../core/configs/cache/IRedisClient';
import { getOrSetCache } from '../shared/cache.util';

@Injectable()
export class clientesService {
  private readonly CUSTOMERS_TTL = 60 * 60 * 12; // 12 horas
  private readonly CUSTOMERS_CACHE_KEY = 'clientes:search';

  constructor(
    @Inject(DATA_SOURCE)
    private readonly dataSource: DataSource,
    @Inject(RedisClientToken)
    private readonly redisClient: IRedisClient,
  ) {}

  /**
   * Buscar clientes com cache otimizado
   * @param filter - Filtro de busca (código, CPF/CNPJ ou nome)
   * @returns Array de clientes encontrados
   */
  async customers(filter: string) {
    const cacheKey = `${this.CUSTOMERS_CACHE_KEY}:${filter}`;

    return getOrSetCache(
      this.redisClient,
      cacheKey,
      this.CUSTOMERS_TTL,
      async () => {
        const queryRunner: QueryRunner = this.dataSource.createQueryRunner();
        await queryRunner.connect();

        try {
          // Primeira tentativa: busca por código do cliente
          let sql = `SELECT  PCCLIENT.CODCLI   as "id"
                            ,PCCLIENT.CODCLI || ' - '|| PCCLIENT.CLIENTE||
                              ' ( '||REGEXP_REPLACE(PCCLIENT.CGCENT, '[^0-9]', '')||' )' as "name"
                            ,PCCLIENT.ESTCOB as "estcob"
                      FROM PCCLIENT
                     WHERE PCCLIENT.CODCLI = REGEXP_REPLACE('${filter}', '[^0-9]', '')
                     ORDER BY PCCLIENT.CLIENTE`;
          let customers = await queryRunner.manager.query(sql);

          // Segunda tentativa: busca por CPF/CNPJ se não encontrou por código
          if (customers.length === 0) {
            sql = `SELECT PCCLIENT.CODCLI as "id",
                          PCCLIENT.CODCLI || ' - '|| PCCLIENT.CLIENTE||
                            ' ( '||REGEXP_REPLACE(PCCLIENT.CGCENT, '[^0-9]', '')||' )' as "name"
                          ,PCCLIENT.ESTCOB as "estcob"
                     FROM PCCLIENT
                    WHERE REGEXP_REPLACE(PCCLIENT.CGCENT, '[^0-9]', '') = REGEXP_REPLACE('${filter}', '[^0-9]', '')
                    ORDER BY PCCLIENT.CLIENTE`;
            customers = await queryRunner.manager.query(sql);
          }

          // Terceira tentativa: busca por nome do cliente se não encontrou por código ou CPF/CNPJ
          if (customers.length === 0) {
            sql = `SELECT PCCLIENT.CODCLI as "id",
                          PCCLIENT.CODCLI || ' - '|| PCCLIENT.CLIENTE||
                            ' ( '||REGEXP_REPLACE(PCCLIENT.CGCENT, '[^0-9]', '')||' )' as "name"
                          ,PCCLIENT.ESTCOB as "estcob"
                     FROM PCCLIENT
                    WHERE PCCLIENT.CLIENTE LIKE '${filter
                      .toUpperCase()
                      .replace('@', '%')}%'
                    ORDER BY PCCLIENT.CLIENTE`;
            customers = await queryRunner.manager.query(sql);
          }

          return customers;
        } finally {
          await queryRunner.release();
        }
      },
    );
  }

  /**
   * Buscar todos os clientes com cache
   * @returns Array de todos os clientes
   */
  async getAllCustomers() {
    const cacheKey = 'clientes:all';

    return getOrSetCache(
      this.redisClient,
      cacheKey,
      this.CUSTOMERS_TTL,
      async () => {
        const queryRunner: QueryRunner = this.dataSource.createQueryRunner();
        await queryRunner.connect();

        try {
          const sql = `SELECT  PCCLIENT.CODCLI   as "id"
                              ,PCCLIENT.CODCLI || ' - '|| PCCLIENT.CLIENTE||
                                ' ( '||REGEXP_REPLACE(PCCLIENT.CGCENT, '[^0-9]', '')||' )' as "name"
                              ,PCCLIENT.ESTCOB as "estcob"
                        FROM PCCLIENT
                       ORDER BY PCCLIENT.CLIENTE`;

          return await queryRunner.manager.query(sql);
        } finally {
          await queryRunner.release();
        }
      },
    );
  }

  /**
   * Buscar cliente por ID específico com cache
   * @param customerId - ID do cliente
   * @returns Cliente encontrado ou null
   */
  async getCustomerById(customerId: string) {
    const cacheKey = `clientes:id:${customerId}`;

    return getOrSetCache(
      this.redisClient,
      cacheKey,
      this.CUSTOMERS_TTL,
      async () => {
        const queryRunner: QueryRunner = this.dataSource.createQueryRunner();
        await queryRunner.connect();

        try {
          const sql = `SELECT  PCCLIENT.CODCLI   as "id"
                              ,PCCLIENT.CODCLI || ' - '|| PCCLIENT.CLIENTE||
                                ' ( '||REGEXP_REPLACE(PCCLIENT.CGCENT, '[^0-9]', '')||' )' as "name"
                              ,PCCLIENT.ESTCOB as "estcob"
                        FROM PCCLIENT
                       WHERE PCCLIENT.CODCLI = '${customerId}'`;

          const customers = await queryRunner.manager.query(sql);
          return customers.length > 0 ? customers[0] : null;
        } finally {
          await queryRunner.release();
        }
      },
    );
  }


  async clearCustomersCache(pattern?: string) {
    const cachePattern = pattern || 'clientes:*';

  }
}