class-amendment.ts

import { AbstractClass } from '@proc7ts/primitives';
import { Amendatory } from '../base';
import { AeClass, DecoratedAeClass } from './ae-class';

/**
 * Class amendment.
 *
 * Can be used as class decorator, unless expects an amended entity other than {@link AeClass}.
 *
 * @typeParam TClass - A type of amended class.
 * @typeParam TAmended - A type of amended entity representing a class to amend.
 */
export type ClassAmendment<
  TClass extends AbstractClass,
  TAmended extends AeClass<TClass> = AeClass<TClass>,
> = AeClass<any> extends TAmended
  ? ClassAmendmentDecorator<TClass>
  : ClassAmendatory<TClass, TAmended>;

export namespace ClassAmendment {
  export type ForBase<
    TBase extends AeClass<TClass>,
    TClass extends AbstractClass,
    TAmended extends TBase,
  > = TBase extends TAmended
    ? ClassAmendmentDecorator<TClass>
    : ClassAmendatory.ForBase<TBase, TClass, TAmended>;
}

/**
 * Class amendatory instance.
 *
 * @typeParam TClass - A type of amended class.
 * @typeParam TAmended - A type of amended entity representing a class to amend.
 */
export interface ClassAmendatory<
  TClass extends AbstractClass,
  TAmended extends AeClass<TClass> = AeClass<TClass>,
> extends ClassAmendatory.ForBase<AeClass<TClass>, TClass, TAmended> {
  /**
   * Decorates the given class.
   *
   * @param decorated - Decorated class representation.
   */
  decorateAmended(this: void, decorated: DecoratedAeClass<TClass, TAmended>): void;
}

export namespace ClassAmendatory {
  /**
   * Class amendatory instance for the given base amended entity type..
   *
   * @typeParam TBase - Base amended entity type.
   * @typeParam TClass - A type of amended class.
   * @typeParam TAmended - A type of amended entity representing a class to amend.
   */
  export interface ForBase<
    TBase extends AeClass<TClass>,
    TClass extends AbstractClass,
    TAmended extends TBase,
  > extends Amendatory<TAmended> {
    /**
     * Decorates the given class.
     *
     * @param decorated - Decorated class representation.
     */
    decorateAmended(this: void, decorated: DecoratedAeClass.ForBase<TBase, TClass, TAmended>): void;
  }
}

/**
 * Class amendment that can be used as class decorator.
 *
 * @typeParam TClass - A type of amended class.
 */
export interface ClassAmendmentDecorator<TClass extends AbstractClass>
  extends ClassAmendatory<TClass> {
  /**
   * Applies this amendment to decorated class.
   *
   * @param classConstructor - Decorated class constructor.
   */
  (this: void, classConstructor: TClass): void;
}