import {
  BadRequestException,
  ForbiddenException,
  Injectable,
  PreconditionFailedException,
} from '@nestjs/common';
import { LoginRequest } from '../interfaces/auth.interface';
import { JWTService } from './jwt.service';
import { ILike, Repository } from 'typeorm';
import { UserEntity } from '../database/entities/user.entity';
import { compare } from 'bcrypt';
import { instanceToPlain } from 'class-transformer';
import { InjectRepository } from '@nestjs/typeorm';
import { OTPService } from './otp.service';
import { BanService } from './ban.service';
import { UserInfo } from '@freeblox/shared';
import { RoleService } from './role.service';
import { ConfigService } from '@nestjs/config';

@Injectable()
export class AuthService {
  constructor(
    private readonly jwtService: JWTService,
    private readonly otpService: OTPService,
    private readonly banService: BanService,
    private readonly roleService: RoleService,
    @InjectRepository(UserEntity)
    private readonly userRepository: Repository<UserEntity>,
    private readonly config: ConfigService,
  ) {}

  /**
   * Login by username/email and password
   * @param body Username/email and password
   * @returns JWT token
   */
  async login(body: LoginRequest) {
    if (!body.email || !body.password) {
      throw new BadRequestException('Invalid username or password');
    }

    // Prevent wildcards
    const userInput = body.email?.replace(/%/g, '');
    const userEntity = await this.userRepository.findOne({
      where: [
        {
          username: ILike(userInput),
          activated: true,
        },
        {
          email: ILike(userInput),
          activated: true,
        },
      ],
    });

    // User not found
    if (!userEntity) {
      throw new BadRequestException('Invalid username or password');
    }

    // Compare passwords
    const passwordMatch = await compare(body.password, userEntity.password);
    if (!passwordMatch) {
      throw new BadRequestException('Invalid username or password');
    }

    // Check TOTP
    const userOTPToken = await this.otpService.getUserTOTP(userEntity);
    if (userOTPToken) {
      if (!body.totpToken) {
        throw new PreconditionFailedException('TOTP Token required');
      }

      const validate = this.otpService.validateTOTP(
        userOTPToken.token,
        body.totpToken,
      );

      if (!validate) {
        throw new ForbiddenException('Invalid TOTP Token');
      }
    }

    // Check for active ban
    const bans = await this.banService.getActiveBansForUser(userEntity);
    const banned = !!bans.length;

    // Get all privileges applicable to user
    const privileges = await this.roleService.getUserPrivileges(userEntity);

    // Issue token
    const exp = this.config.get('security.tokenExpiry');
    const issuedToken = await this.jwtService.sign({
      sub: userEntity.id,
      username: userEntity.username,
      display_name: userEntity.displayName,
      language: userEntity.language,
      banned: banned,
      privileges: banned
        ? []
        : privileges.map((privilege) => privilege.privilege),
    });

    // Set login time to now
    await this.userRepository.update(
      { id: userEntity.id },
      { loginAt: new Date() },
    );

    return {
      token: issuedToken,
      expires_in: exp,
    };
  }

  /**
   * Get user from token
   * @param token JWT Token
   * @returns User entity
   */
  async getUserFromToken(token: string) {
    const tokenInfo = await this.verifyToken(token);
    const user = await this.userRepository.findOneByOrFail({
      id: tokenInfo.sub,
      activated: true,
    });
    return instanceToPlain(user);
  }

  /**
   * Verify user token
   * @param token JWT token
   * @returns User token info
   */
  async verifyToken(token: string) {
    try {
      return await this.jwtService.verify(token);
    } catch (e) {
      console.error(token, e);
      throw new ForbiddenException('Invalid token');
    }
  }

  /**
   * Get user entity by ID
   * @param id User ID
   * @returns User entity
   */
  async getUserById(id: string) {
    if (!id) throw new BadRequestException('ID is required');
    return instanceToPlain(await this.userRepository.findOneByOrFail({ id }));
  }

  /**
   * Get user bans
   * @param tokeninfo
   */
  async getUserBans(userInfo: UserInfo) {
    const user = await this.userRepository.findOneByOrFail({
      id: userInfo.sub,
      activated: true,
    });
    const bans = await this.banService.getAllBansForUser(user);
    return instanceToPlain(bans);
  }
}