gsender

/*
 * Copyright (C) 2021 Sienci Labs Inc.
 *
 * This file is part of gSender.
 *
 * gSender is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, under version 3 of the License.
 *
 * gSender is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with gSender.  If not, see <https://www.gnu.org/licenses/>.
 *
 * Contact for information regarding this program and its license
 * can be sent through gSender@sienci.com or mailed to the main office
 * of Sienci Labs Inc. in Waterloo, Ontario, Canada.
 *
 */

import events from "events";
import _ from "lodash";

class ImmutableStore extends events.EventEmitter {
	state = {};

	constructor(state = {}) {
		super();

		this.state = state;
	}

	get(key, defaultValue) {
		return _.get(this.state, key, defaultValue);
	}

	set(key, value) {
		this.state = _.merge({}, this.state, _.set({}, key, value));
		this.emit("change", this.state);
		return this.state;
	}

	unset(key) {
		const state = _.extend({}, this.state);
		_.unset(state, key);
		this.state = state;
		this.emit("change", this.state);
		return this.state;
	}

	replace(key, value) {
		this.unset(key);
		this.set(key, value);
	}

	clear() {
		this.state = {};
		this.emit("change", this.state);
		return this.state;
	}
}

export default ImmutableStore;