import {
  IsIn,
  IsNotEmpty,
  IsNotIn,
  IsOptional,
  IsUrl,
  validateSync,
} from 'class-validator';
import { plainToInstance } from 'class-transformer';

export class EnvironmentVariables {
  @IsNotEmpty()
  @IsUrl(
    { protocols: ['postgres', 'postgresql'], require_tld: false },
    { message: 'DATABASE_URL must be a valid postgres connection string' },
  )
  DATABASE_URL: string;

  @IsNotEmpty()
  @IsUrl(
    { protocols: ['redis', 'rediss'], require_tld: false },
    { message: 'REDIS_URL must be a valid redis connection string' },
  )
  REDIS_URL: string;

  @IsOptional()
  @IsUrl({ protocols: ['http', 'https'], require_tld: false })
  APP_URL: string;

  @IsNotEmpty()
  @IsNotIn(['REPLACE_WITH_LONG_SECRET'])
  APP_SECRET: string;

  @IsOptional()
  @IsIn(['smtp', 'postmark'])
  MAIL_DRIVER: string;

  @IsOptional()
  @IsIn(['local', 's3'])
  STORAGE_DRIVER: string;
}

export function validate(config: Record<string, any>) {
  const validatedConfig = plainToInstance(EnvironmentVariables, config);

  const errors = validateSync(validatedConfig);

  if (errors.length > 0) {
    console.error(
      'The Environment variables has failed the following validations:',
    );

    errors.map((error) => {
      console.error(JSON.stringify(error.constraints));
    });

    console.error(
      'Please fix the environment variables and try again. Exiting program...',
    );
    process.exit(1);
  }

  return validatedConfig;
}