import { Strategy, VerifyCallback } from 'passport-google-oauth20';
import { PassportStrategy } from '@nestjs/passport';
import { Injectable, UnauthorizedException } from '@nestjs/common';
import { UserService } from 'src/user/user.service';
import * as O from 'fp-ts/Option';
import { AuthService } from '../auth.service';
import * as E from 'fp-ts/Either';

@Injectable()
export class GoogleStrategy extends PassportStrategy(Strategy) {
  constructor(
    private usersService: UserService,
    private authService: AuthService,
  ) {
    super({
      clientID: process.env.GOOGLE_CLIENT_ID,
      clientSecret: process.env.GOOGLE_CLIENT_SECRET,
      callbackURL: process.env.GOOGLE_CALLBACK_URL,
      scope: process.env.GOOGLE_SCOPE.split(','),
      passReqToCallback: true,
      store: true,
    });
  }

  async validate(
    req: Request,
    accessToken,
    refreshToken,
    profile,
    done: VerifyCallback,
  ) {
    const user = await this.usersService.findUserByEmail(
      profile.emails[0].value,
    );

    if (O.isNone(user)) {
      const createdUser = await this.usersService.createUserSSO(
        accessToken,
        refreshToken,
        profile,
      );
      return createdUser;
    }

    /**
     * * displayName and photoURL maybe null if user logged-in via magic-link before SSO
     */
    if (!user.value.displayName || !user.value.photoURL) {
      const updatedUser = await this.usersService.updateUserDetails(
        user.value,
        profile,
      );
      if (E.isLeft(updatedUser)) {
        throw new UnauthorizedException(updatedUser.left);
      }
    }

    /**
     * * Check to see if entry for Google is present in the Account table for user
     * * If user was created with another provider findUserByEmail may return true
     */
    const providerAccountExists =
      await this.authService.checkIfProviderAccountExists(user.value, profile);

    if (O.isNone(providerAccountExists))
      await this.usersService.createProviderAccount(
        user.value,
        accessToken,
        refreshToken,
        profile,
      );

    return user.value;
  }
}