import { IS_PUBLIC_KEY } from '@hedhog/core';
import {
  CanActivate,
  ExecutionContext,
  Injectable,
  UnauthorizedException,
} from '@nestjs/common';
import { Reflector } from '@nestjs/core';
import { Request } from 'express';
import { AuthService } from '../auth.service';

@Injectable()
export class AuthGuard implements CanActivate {
  constructor(
    private auth: AuthService,
    private reflector: Reflector,
  ) {}

  async canActivate(context: ExecutionContext): Promise<boolean> {
    const isPublic = this.reflector.getAllAndOverride<boolean>(IS_PUBLIC_KEY, [
      context.getHandler(),
      context.getClass(),
    ]);

    const request = context.switchToHttp().getRequest();
    const token = this.extractTokenFromHeader(request);

    if (!token) {
      if (isPublic) {
        return true;
      } else {
        throw new UnauthorizedException();
      }
    }
    try {
      const payload = await this.auth.verifyToken(token);

      request['auth'] = payload;
    } catch (error) {
      if (isPublic) {
        return true;
      } else {
        throw new UnauthorizedException(error);
      }
    }
    return true;
  }

  private extractTokenFromHeader(request: Request): string | undefined {
    const [type, token] = request.headers.authorization?.split(' ') ?? [];

    return type === 'Bearer' ? token : undefined;
  }
}