modelling/lib/ControlModel.ts

/*
 * Copyright (C) Sapphirecode - All Rights Reserved
 * This file is part of Modelling which is released under MIT.
 * See file 'LICENSE' for full license details.
 * Created by Timo Hocker <timo@scode.ovh>, May 2020
 */

import { Persistent } from './Persistent';
import { PersistentType, ControlObserver, Observer } from './Types';

export abstract class ControlModel extends Persistent {
  private _before_change: Record<string, ControlObserver[]> = {};
  private _observers: Record<string, Observer[]> = {};

  public constructor (obj?: Record<string, PersistentType>) {
    super ();
    this.define_properties ();
    if (typeof obj !== 'undefined')
      this.assign_object (obj);
  }

  public set (key: string, value: PersistentType): void {
    const prev = this.get (key);
    if (typeof this._before_change[key] !== 'undefined') {
      for (const obs of this._before_change[key]) {
        if (!obs (value, prev, key))
          return;
      }
    }

    super.set (key, value);
    if (typeof this._observers[key] !== 'undefined') {
      for (const obs of this._observers[key])
        obs (value, prev, key);
    }
  }

  public before_change (key: string, func: ControlObserver): void {
    if (typeof this._before_change[key] === 'undefined')
      this._before_change[key] = [];
    this._before_change[key].push (func);
  }

  public register_observer (key: string, func: Observer): void {
    if (typeof this._observers[key] === 'undefined')
      this._observers[key] = [];
    this._observers[key].push (func);
  }

  protected abstract define_properties(): void;
}