import {
  CanActivate,
  ExecutionContext,
  Injectable,
  UnauthorizedException,
} from '@nestjs/common';
import { ConfigService } from '@nestjs/config';
import { Reflector } from '@nestjs/core';
import { JwtService } from '@nestjs/jwt';
import { Request } from 'express';
import { RedisService } from 'src/common/helpers/redis.service';
import { EncryptionHelper } from 'src/common/tools/encryption-helper';
import { IS_PUBLIC_KEY } from './auth.decorator';

@Injectable()
export class AppGuard implements CanActivate {
  constructor(
    private readonly jwtService: JwtService,
    private readonly reflector: Reflector,
    private readonly redisService: RedisService,
  ) {}

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

    const request = context.switchToHttp().getRequest();
    const token = this.extractTokenFromHeader(request);
    if (!token) {
      throw new UnauthorizedException('توکن الزامی است');
    }

    try {
      const isBlacklisted = await this.redisService.isTokenBlacklisted(token); // ✅ Using service method
      if (isBlacklisted) {
        throw new UnauthorizedException('توکن در لیست سیاه قرار دارد');
      }

      const decryptedToken = EncryptionHelper.decrypt(token);
      const payload = await this.jwtService.verifyAsync(decryptedToken, {
        secret: process.env.auth_jwt_secret,
        // issuer: process.env.auth_jwt_issuer,
      });
      //    await bcrypt. JSON.parse(payload)
      request['user'] = payload;
    } catch {
      throw new UnauthorizedException('عدم احراز هویت');
    }
    return true;
  }

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

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