fix: URL changes so fast

fixes #252

Author: RomanHotsiy

lib/services/hash.service.ts

@@ -1,15 +1,20 @@
 'use strict';
 import { Injectable } from '@angular/core';
 import { PlatformLocation } from '@angular/common';
-
 import { BehaviorSubject } from 'rxjs/BehaviorSubject';
 
+import { debounce } from '../utils/';
+
 @Injectable()
 export class Hash {
   public value = new BehaviorSubject<string | null>(null);
   private noEmit:boolean = false;
+  private debouncedUpdate: (hash:string, rewrite: boolean) => void;
+
   constructor(private location: PlatformLocation) {
     this.bind();
+
+    this.debouncedUpdate = debounce(this._update.bind(this), 100);
   }
 
   start() {
@@ -28,6 +33,10 @@ export class Hash {
   }
 
   update(hash: string|null, rewriteHistory:boolean = false) {
+    this.debouncedUpdate(hash, rewriteHistory);
+  }
+
+  private _update(hash: string|null, rewriteHistory:boolean = false) {
     if (hash == undefined) return;
     if (rewriteHistory) {
       window.history.replaceState(null, '', window.location.href.split('#')[0] + '#' + hash);
@@ -39,4 +48,5 @@ export class Hash {
       this.noEmit = false;
     });
   }
+
 }

lib/utils/helpers.ts

@@ -99,6 +99,21 @@ export function throttle(fn, threshhold, scope) {
   };
 }
 
+export function debounce(func, wait, immediate = false) {
+	var timeout;
+	return function() {
+		var context = this, args = arguments;
+		var later = function() {
+			timeout = null;
+			if (!immediate) func.apply(context, args);
+		};
+		var callNow = immediate && !timeout;
+		clearTimeout(timeout);
+		timeout = setTimeout(later, wait);
+		if (callNow) func.apply(context, args);
+	};
+}
+
 export const isSafari = Object.prototype.toString.call(window.HTMLElement).indexOf('Constructor') > 0
   || (function (p) { return p.toString() === '[object SafariRemoteNotification]'; })(!window['safari']
   || safari.pushNotification);