import { Injectable, UnauthorizedException } from '@nestjs/common';
import { JwtService } from '@nestjs/jwt';
import { UserService } from '../users/user.service';
import * as bcrypt from 'bcrypt';

@Injectable()
export class AuthService {
  constructor(
    private readonly userService: UserService,
    private readonly jwtService: JwtService,
  ) {}

  async getProfile(userId: string) {
    return this.userService.findById(userId);
  }

  async validateUser(email: string, password: string): Promise<any> {
    const user = await this.userService.findByEmail(email);
    if (!user) {
      throw new UnauthorizedException('Invalid credentials');
    }

    const isValidPassword = await bcrypt.compare(password, user.passwordHash);
    if (!isValidPassword) {
      throw new UnauthorizedException('Invalid credentials');
    }

    return user;
  }

  async login(user: any) {
    const payload = { sub: user.id, email: user.email, role: user.role?.name || user.role };
    return {
      accessToken: this.jwtService.sign(payload),
      user: {
        id: user.id,
        email: user.email,
        firstName: user.firstName,
        lastName: user.lastName,
        role: user.role?.name || user.role,
      },
    };
  }

  async register(userData: any) {
    const hashedPassword = await bcrypt.hash(userData.password, 10);
    const user = await this.userService.create({
      ...userData,
      passwordHash: hashedPassword,
      role: 'customer',
    });
    return this.login(user);
  }
}