import {AbstractControl, FormArray, FormControl, FormGroup} from "@angular/forms";

export function isNullOrUndefined(object: any): boolean {
	return object === null || object === undefined;
}

export function isNumeric(val: any): val is number | string {
	return !Array.isArray(val) && (val - parseFloat(val) + 1) >= 0;
}

/**
 * Deep clones the given AbstractControl, preserving values, validators, async validators, and disabled status.
 * @param control AbstractControl
 * @returns AbstractControl
 */
export function cloneAbstractControl<T extends AbstractControl>(control: T): T {
	let newControl: T;

	if (control instanceof FormGroup) {
		const formGroup = new FormGroup({}, control.validator, control.asyncValidator);
		const controls = control.controls;

		Object.keys(controls).forEach(key => {
			formGroup.addControl(key, cloneAbstractControl(controls[key]));
		})

		newControl = formGroup as any;
	}
	else if (control instanceof FormArray) {
		const formArray = new FormArray([], control.validator, control.asyncValidator);

		control.controls.forEach(formControl => formArray.push(cloneAbstractControl(formControl)))

		newControl = formArray as any;
	}
	else if (control instanceof FormControl) {
		newControl = new FormControl(control.value, control.validator, control.asyncValidator) as any;
	}
	else {
		throw new Error('Error: unexpected control value');
	}

	if (control.disabled) newControl.disable({emitEvent: false});

	return newControl;
}