export default class FlagsEnum {
	/**
	 * Determines if flag-enum contains specified flag
	 *
	 * @param value Value of the flag-enum
	 * @param flag Flag searched
	 */
	static enumHasFlag(value: number, flag: number): boolean {
		return (value & flag) == flag;
	}

	/**
	 * Adds flag to enum if not already present
	 *
	 * @param value Value of the flag-enum
	 * @param flag Flag searched
	 */
	static addFlagToEnum(value: number, flag: number): number {
		if (!FlagsEnum.enumHasFlag(value, flag)) {
			value += flag;
		}

		return value;
	}

	/**
	 * Removes flag from the enum if present
	 *
	 * @param value Value of the flag-enum
	 * @param flag Flag searched
	 */
	static removeFlagFromEnum(value: number, flag: number): number {
		if (FlagsEnum.enumHasFlag(value, flag)) {
			value -= flag;
		}

		return value;
	}

	/**
	 * Toggles flags enum to given state
	 *
	 * @param value Value of the flag-enum
	 * @param flag Flag searched
	 * @param present Determines if the flag is presented
	 */
	static toggleEnumFlag(
		value: number,
		flag: number,
		present: boolean,
	): number {
		if (present) {
			return FlagsEnum.addFlagToEnum(value, flag);
		} else {
			return FlagsEnum.removeFlagFromEnum(value, flag);
		}
	}
}