lots of important stuff (#1883)

* lots of important stuff

* Update Constants.js

src/client/BaseClient.js

@@ -0,0 +1,126 @@
+const EventEmitter = require('events');
+const RESTManager = require('../rest/RESTManager');
+const ClientDataResolver = require('./ClientDataResolver');
+const Util = require('../util/Util');
+const Constants = require('../util/Constants');
+
+/**
+ * The base class for all clients.
+ * @extends {EventEmitter}
+ */
+class BaseClient extends EventEmitter {
+  constructor(options = {}) {
+    super();
+
+    /**
+     * The options the client was instantiated with
+     * @type {ClientOptions}
+     */
+    this.options = Util.mergeDefault(Constants.DefaultOptions, options);
+
+    /**
+     * The REST manager of the client
+     * @type {RESTManager}
+     * @private
+     */
+    this.rest = new RESTManager(this, options._tokenType);
+
+    /**
+     * The data resolver of the client
+     * @type {ClientDataResolver}
+     * @private
+     */
+    this.resolver = new ClientDataResolver(this);
+
+    /**
+     * Timeouts set by {@link WebhookClient#setTimeout} that are still active
+     * @type {Set<Timeout>}
+     * @private
+     */
+    this._timeouts = new Set();
+
+    /**
+     * Intervals set by {@link WebhookClient#setInterval} that are still active
+     * @type {Set<Timeout>}
+     * @private
+     */
+    this._intervals = new Set();
+  }
+
+  /**
+   * Whether the client is in a browser environment
+   * @type {boolean}
+   * @readonly
+   */
+  get browser() {
+    return typeof window !== 'undefined';
+  }
+
+  /**
+   * API shortcut
+   * @type {Object}
+   * @private
+   */
+  get api() {
+    return this.rest.api;
+  }
+
+  /**
+   * Destroys all assets used by the base client.
+   */
+  destroy() {
+    for (const t of this._timeouts) clearTimeout(t);
+    for (const i of this._intervals) clearInterval(i);
+    this._timeouts.clear();
+    this._intervals.clear();
+  }
+
+  /**
+   * Sets a timeout that will be automatically cancelled if the client is destroyed.
+   * @param {Function} fn Function to execute
+   * @param {number} delay Time to wait before executing (in milliseconds)
+   * @param {...*} args Arguments for the function
+   * @returns {Timeout}
+   */
+  setTimeout(fn, delay, ...args) {
+    const timeout = setTimeout(() => {
+      fn(...args);
+      this._timeouts.delete(timeout);
+    }, delay);
+    this._timeouts.add(timeout);
+    return timeout;
+  }
+
+  /**
+   * Clears a timeout.
+   * @param {Timeout} timeout Timeout to cancel
+   */
+  clearTimeout(timeout) {
+    clearTimeout(timeout);
+    this._timeouts.delete(timeout);
+  }
+
+  /**
+   * Sets an interval that will be automatically cancelled if the client is destroyed.
+   * @param {Function} fn Function to execute
+   * @param {number} delay Time to wait before executing (in milliseconds)
+   * @param {...*} args Arguments for the function
+   * @returns {Timeout}
+   */
+  setInterval(fn, delay, ...args) {
+    const interval = setInterval(fn, delay, ...args);
+    this._intervals.add(interval);
+    return interval;
+  }
+
+  /**
+   * Clears an interval.
+   * @param {Timeout} interval Interval to cancel
+   */
+  clearInterval(interval) {
+    clearInterval(interval);
+    this._intervals.delete(interval);
+  }
+}
+
+module.exports = BaseClient;