import { Directive, Input, OnInit } from '@angular/core';
import { NgControl } from '@angular/forms';

@Directive({
  selector: '[mkDisableControl]'
})
export class DisableControlDirective implements OnInit {

  private _currentState = false;

  constructor(private _ngControl: NgControl) {
  }

  get mkDisableControl(): boolean {
    return this._currentState;
  }

  @Input()
  set mkDisableControl(condition: boolean) {
    this._currentState = condition;
    this._applyDisableState(this._currentState);
  }

  ngOnInit(): void {
    if (this._ngControl.control) {
      this._ngControl.control.statusChanges.subscribe(
        state => {
          const active = state === 'DISABLED';
          if (active !== this._currentState) {
            this._applyDisableState(this._currentState);
          }
        }
      );
    }
  }

  private _applyDisableState(state: boolean): void {
    if (this._ngControl.control) {
      if (state) {
        this._ngControl.control.disable();
      }
      else {
        this._ngControl.control.enable();
      }
    }
  }
}