Issue 2844 - Create Microsoft Edge coming soon landing page

static/js/index.js

 (function()
 {
+  function addListener(obj, type, listener, useCapture)
+  {
+    if ("addEventListener" in obj)
+    {
+      obj.addEventListener(type, function(ev)
+      {
+        if (listener(ev) === false)
+          ev.preventDefault();
+      }, useCapture);
+    }
+    else
+    {
+      // IE 8
+      if (type == "DOMContentLoaded")
+        type = "readystatechange";
+
+      type = "on" + type;
+      if ("attachEvent" in obj)
+      {
+        obj.attachEvent(type, function()
+        {
+          if (document.readyState == "complete" && listener(event) === false)
+            event.returnValue = false;
+        });
+      }
+      else
+      {
+        obj[type] = listener;
+      }
+    }
+  }
+
+  function addPlaceholder(textbox)
+  {
+    textbox.setAttribute("class", "placeholder");
+    textbox.value = getPlaceholderText(textbox);
+  }
+
+  function getPlaceholderText(textbox)
+  {
+    return textbox.getAttribute("placeholder");
+  }
+
+  function initSubscriptionForm(subscriptionElement)
+  {
+    var emailTextbox = subscriptionElement.getElementsByClassName("subscribe-textbox")[0];
+
+    // IE9 + Safari iOS
+    if (!("placeholder" in document.createElement("input"))
+        && !emailTextbox.value)
+    {
+      addPlaceholder(emailTextbox);
+      addListener(emailTextbox, "focus", function()
+      {
+        if (emailTextbox.value == getPlaceholderText(textbox))
+        {
+          emailTextbox.value = "";
+          emailTextbox.setAttribute("class", "");
+        }
+      }, false);
+
+      addListener(emailTextbox, "blur", function()
+      {
+        if (!emailTextbox.value)
+          addPlaceholder(emailTextbox);
+      }, false);
+    }
+
+    var formElement = subscriptionElement.getElementsByTagName("form")[0];
+    addListener(formElement, "submit", function()
+    {
+      if (!window.XMLHttpRequest)
+      {
+        formElement.submit();
+        return false;
+      }
+
+      var inputs = formElement.getElementsByTagName("input");
+      var params = "";
+      for (var i = 0; i < inputs.length; i++)
+      {
+        if (params)
+          params += "&";
+        params += inputs[i].name + "=" + encodeURIComponent(inputs[i].value);
+      }      
+      var request = new XMLHttpRequest();
+      request.open("POST", "/submitEmail", true);
+      request.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");
+      addListener(request, "readystatechange", function()
+      {
+        if (request.readyState == 4)
+        {
+          if (request.status >= 200 && request.status < 300)
+          {
+            formElement.setAttribute("class", "success");
+          }
+          else if (request.status == 400)
+          {
+            formElement.setAttribute("class", "invalid");
+          }
+          else
+          {
+            var errorWrapper = document.getElementById("response-error");
+            if ("textContent" in errorWrapper)
+              errorWrapper.textContent = request.statusText;
+            else // IE8
+              errorWrapper.innerText = request.statusText;
+
+            formElement.setAttribute("class", "error");
+          }
+        }
+      }, false);
+      request.send(params);
+      return false;
+    }, false);
+  }
+
   var visibleTab;
   var container;
-  
+
   window.toggleMore = function()
   {
     if (container.className == "hidden")
       container.className = visibleTab || getDefaultTab();
     else
       container.className = "hidden";
   }
-  
+
   window.showTab = function(button)
   {
     var id = button.id.substr(5);
     container.className = id;
     visibleTab = id;
   }
-  
+
   function getDefaultTab()
   {
     var content = document.getElementById("content");
     var ua = content.className.match(/ua\-([^\s]+)/);
     visibleTab = ua && ua[1] || "firefox";
     return visibleTab;
   }
-  
+
   function init()
   {
     container = document.getElementById("more-container");
+    initSubscriptionForm(document.getElementById("edge-subscription"));
   }
-  
+
   init();
 })();