import { IsInt, IsOptional, IsString, MinLength, Validate } from 'class-validator';
import { Category } from './category.entity';
import { Unique } from './validator';

export class CategoryDto {
  @IsInt()
  // checks if value of CategoryDto.id is unique by searching in Category.id in DB
  @Validate(Unique, [Category])
  public id: string;
  
  @IsString()
  // checks if value of CategoryDto.title is unique by searching in Category.title in DB
  @Validate(Unique, [Category])
  public title: string;
  
  @IsString()
  // checks if value of CategoryDto.someField is unique by searching in Category.title in DB
  @Validate(Unique, [Category, 'title'])
  public someField: string;
  
  @Column()
  @IsNotEmpty()
  @IsString()
  // checks if pair of provided title+description is unique in DB
  @Validate(
    Unique,
    [
      Category,
      ({ object: { title, description } }: { object: CategoryForm }) => ({
        title,
        description,
      }),
    ],
    {
      message: ({
        targetName,
      }: ValidationArguments) =>
        `${targetName} with the same pair of title and description already exist`,
    },
  )
  public description: string;
}