import { Column, Entity, ManyToOne, PrimaryGeneratedColumn } from 'typeorm';
import { TransformationType } from './transformation-type';
import { Work } from './work';

/**
 * This entity describes how one work is transformed to another.
 */
@Entity()
export class Transformation implements IIdentifiableEntity, IOrderableEntity {
  @PrimaryGeneratedColumn()
  public id!: number;

  /**
   * the work based on the original
   */
  @ManyToOne(() => Work, (work: Work) => work.transformationOf, {
    nullable: false,
    onDelete: 'CASCADE',
    onUpdate: 'CASCADE',
  })
  public byWork!: Promise<Work>;

  /**
   * the transformation type
   */
  @ManyToOne(() => TransformationType, (transformationType: TransformationType) => transformationType.transformations, {
    nullable: false,
    onDelete: 'RESTRICT',
    onUpdate: 'CASCADE',
  })
  public type!: Promise<TransformationType>;

  /**
   * the original work
   */
  @ManyToOne(() => Work, (work: Work) => work.transformedBy, {
    nullable: false,
    onDelete: 'CASCADE',
    onUpdate: 'CASCADE',
  })
  public ofWork!: Promise<Work>;

  @Column({
    nullable: false,
    default: 0,
  })
  public order!: number;
}