import { Injectable, BadRequestException } from '@nestjs/common';
import { JwtService } from '@nestjs/jwt';
import { PrismaService } from '../prisma/prisma.service';
import { RedisService } from '../redis/redis.service';
import { SendOtpDto } from './dto/send-otp.dto';
import { VerifyOtpDto } from './dto/verify-otp.dto';

@Injectable()
export class AuthService {
  constructor(
    private prisma: PrismaService,
    private jwtService: JwtService,
    private redisService: RedisService,
  ) {}

  async sendOtp(sendOtpDto: SendOtpDto) {
    const { phoneNumber } = sendOtpDto;

    const code = Math.floor(10000 + Math.random() * 90000).toString();
    console.log(`[Mock SMS] Sending OTP ${code} to ${phoneNumber}`);

    await this.redisService.set(`otp:${phoneNumber}`, code, 120);

    return { success: true, message: 'کد تایید ارسال شد', code };
  }

  async verifyOtp(verifyOtpDto: VerifyOtpDto) {
    const { phoneNumber, code } = verifyOtpDto;

    const savedCode = await this.redisService.get(`otp:${phoneNumber}`);

    if (!savedCode) {
      throw new BadRequestException({ message: 'کد تایید منقضی شده است', error: 'OTP_EXPIRED' });
    }

    if (savedCode !== code) {
      throw new BadRequestException({ message: 'کد تایید اشتباه است', error: 'OTP_INVALID' });
    }

    await this.redisService.del(`otp:${phoneNumber}`);

    let user = await this.prisma.user.findUnique({ where: { mobile: phoneNumber } });

    if (!user) {
      user = await this.prisma.user.create({
        data: { 
          mobile: phoneNumber,
          firstName: 'کاربر',
          lastName: 'جدید',
          email: `${phoneNumber}@temp.local`,
        },
      });
    }

    const payload = { sub: user.id, phoneNumber: user.mobile };
    const accessToken = this.jwtService.sign(payload);

    return {
      success: true,
      data: {
        user,
        accessToken,
      },
    };
  }

  async adminLogin(body: any) {
    if (body.email === 'admin@canina-iran.com' && body.password === 'admin123') {
      const payload = { sub: '12345678-1234-1234-1234-123456789012', email: body.email, role: 'Admin' };
      return {
        success: true,
        data: {
          user: { id: '12345678-1234-1234-1234-123456789012', email: body.email, role: 'Admin' },
          accessToken: this.jwtService.sign(payload),
        },
      };
    }
    throw new BadRequestException({ message: 'ایمیل یا رمز عبور اشتباه است', error: 'INVALID_CREDENTIALS' });
  }
}