tidy up comments and use of constant for storage key

js/coinbin.js

@@ -8,6 +8,8 @@ $(document).ready(function() {
 
 	var wallet_timer = false;
 
+	var LOCALSTORAGE_COIN_KEY = "coinjs_coin_option"
+
 	$("#openBtn").click(function(){
 		var email = $("#openEmail").val().toLowerCase();
 		if(email.match(/[\s\w\d]+@[\s\w\d]+/g)){
@@ -1933,7 +1935,7 @@ $(document).ready(function() {
 
 	$("#coinjs_coin").change(function(){
 		// set localStorage for use after page (re)load
-		localStorage.setItem("coinbin_coin_option", $(this).val());
+		localStorage.setItem(LOCALSTORAGE_COIN_KEY, $(this).val());
 
 		optionSeleted = ($("option:selected",this).attr("rel")).split(";");
 
@@ -2287,10 +2289,10 @@ $(document).ready(function() {
 		return true;
 	};
 
-	/* set network from cookie on page load */
+	/* set network from localStorage on page load */
 
 	function setNetwork () {
-		var storageItem = localStorage.getItem("coinbin_coin_option");
+		var storageItem = localStorage.getItem(LOCALSTORAGE_COIN_KEY);
 		if(storageItem)
 		{
 			$("#coinjs_coin").val(storageItem)

js/cookie.js

@@ -0,0 +1,82 @@
+class Cookie {
+    constructor(name) {
+        this.name = name;
+        this.value;
+
+        // read the cookies value (initializes value)
+        this.get();
+    }
+
+    get() {
+        var allCookies = document.cookie;
+        var cookie;
+
+        // find out how much cookies are set to be able to pick the right one
+        if(!allCookies)
+        {
+            // the tray is empty. leave fields as initialized
+            return;
+        }
+
+        if(allCookies.indexOf(";") > 0)
+        {
+            // many cookies found, pick one
+            cookie = this.pickCookie(allCookies);
+        } else {
+            // only one cookie found. Check if its the right one
+            if(this.validateCookie(allCookies))
+            {
+                cookie = allCookies;
+            }
+        }
+
+        // read contents of the picked cookie
+        if(cookie) {
+            this.value = this.readCookieContents(cookie);
+        } else {
+            console.log("Coudn't get cookie");
+        }
+    }
+
+    pickCookie(manyCookies) {
+        manyCookies.split(";").forEach((cookie, _) => {
+            if(this.validateCookie(cookie))
+            {
+                return cookie;
+            }
+        });
+    }
+
+    validateCookie(cookie) {
+        if(cookie.indexOf("=") >= 0)
+        {
+            var cookieCredentials = cookie.split("=");
+            var name = cookieCredentials[0]
+            return name == this.name;
+        } else {
+            return false;
+        }
+    }
+
+    readCookieContents(cookie) {
+        var cookieCredentials = cookie.split("=");
+        var value = cookieCredentials[1];
+        return JSON.parse(value);
+    }
+
+    setValue(valueToBeSet) {
+        // update internal record
+        this.value = valueToBeSet;
+
+        // prepare value for storing
+        var valueJSON = JSON.stringify(valueToBeSet);
+
+        // set cookie with expiry on browser close
+        document.cookie = this.name+"="+valueJSON;
+    }
+
+    getValue() {
+        this.get();
+        return this.value;
+    }
+}