abstract-things/lights/light-state.js

Base for building libraries that interact with physical things, such as IoT-devices

'use strict';

const Thing = require('../thing');
const RestorableState = require('../common/restorable-state');

module.exports = Thing.mixin(Parent => class extends Parent.with(RestorableState) {
	/**
	 * Set the state of this light. The default implementation simply
	 * delegates to `change`-methods in capabilities.
	 *
	 * For light implementations that support changing several properties
	 * at once it is recommended to override this method to do manual state
	 * switching.
	 *
	 * @param {object} state
	 */
	setLightState(state) {
		return Promise.resolve();
	}

	mapLightState(state) {
	}

	/**
	 * Restore the state of this light. Hooks into those lights that support
	 * action and delegates restore to `restoreLightState`.
	 *
	 * @param {object} state
	 */
	changeState(state) {
		try {
			return Promise.resolve(super.changeState(state))
				.then(() => {
					const stateCopy = Object.assign({}, state);
					this.mapLightState(stateCopy);
					return this.setLightState(stateCopy);
				});
		} catch(ex) {
			return Promise.reject(ex);
		}
	}
});