Add Document, Window, and Body

Fixes #124

Ooui/Body.cs

@@ -0,0 +1,13 @@
+using System;
+
+namespace Ooui
+{
+    public class Body : Element
+    {
+        public Body ()
+            : base ("Body")
+        {
+            Id = "document.body";
+        }
+    }
+}

Ooui/Document.cs

@@ -0,0 +1,23 @@
+using System;
+
+namespace Ooui
+{
+    public class Document : EventTarget
+    {
+        public Window Window { get; } = new Window ();
+        public Body Body { get; } = new Body ();
+
+        public Document ()
+            : base ("document")
+        {
+            Id = "document";
+            Window.MessageSent += Proxy_MessageSent;
+            Body.MessageSent += Proxy_MessageSent;
+        }
+
+        void Proxy_MessageSent (Message message)
+        {
+            Send (message);
+        }
+    }
+}

Ooui/Element.cs

@@ -1,6 +1,7 @@
 using System;
 using System.Collections.Generic;
 using System.ComponentModel;
+using System.Threading;
 
 namespace Ooui
 {
@@ -8,6 +9,8 @@ namespace Ooui
     {
         readonly Dictionary<string, object> attributes = new Dictionary<string, object> ();
 
+        Document document = null;
+
         public string ClassName {
             get => GetStringAttribute ("class", "");
             set => SetAttributeProperty ("class", value);
@@ -90,6 +93,17 @@ namespace Ooui
             remove => RemoveEventListener ("wheel", value);
         }
 
+        public Document Document {
+            get {
+                if (document == null) {
+                    if (Interlocked.CompareExchange (ref document, new Document (), null) == null) {
+                        document.MessageSent += Document_MessageSent;
+                    }
+                }
+                return document;
+            }
+        }
+
         /// <summary>
         /// A signal to Ooui that this element should take up the
         /// entire browser window.
@@ -229,6 +243,11 @@ namespace Ooui
             SendSet ("style." + Style.GetJsName (e.PropertyName), Style[e.PropertyName]);
         }
 
+        void Document_MessageSent (Message message)
+        {
+            Send (message);
+        }
+
         protected virtual bool HtmlNeedsFullEndElement => false;
 
 #if !NO_XML

Ooui/EventTarget.cs

@@ -13,7 +13,7 @@ namespace Ooui
         readonly Dictionary<string, List<TargetEventHandler>> eventListeners =
             new Dictionary<string, List<TargetEventHandler>> ();
 
-        public string Id { get; private set; } = GenerateId ();
+        public string Id { get; protected set; } = GenerateId ();
 
         public string TagName { get; private set; }
 

Ooui/Window.cs

@@ -0,0 +1,24 @@
+namespace Ooui
+{
+    public class Window : EventTarget
+    {
+        string location = "";
+
+        public string Location {
+            get => location;
+            set {
+                if (string.IsNullOrEmpty (value) || location == value)
+                    return;
+                location = value;
+                Send (Message.Set ("window", "location", value));
+                OnPropertyChanged ("Location");
+            }
+        }
+
+        public Window ()
+            : base ("window")
+        {
+            Id = "window";
+        }
+    }
+}

Tests/WindowTests.cs

@@ -0,0 +1,93 @@
+using System;
+
+#if NUNIT
+using NUnit.Framework;
+using TestClassAttribute = NUnit.Framework.TestFixtureAttribute;
+using TestMethodAttribute = NUnit.Framework.TestCaseAttribute;
+#else
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+#endif
+
+using Ooui;
+
+namespace Tests
+{
+    [TestClass]
+    public class WindowTests
+    {
+        [TestMethod]
+        public void ElementDocumentNotNull ()
+        {
+            var b = new Button ();
+            Assert.IsNotNull (b.Document);
+        }
+
+        [TestMethod]
+        public void DocumentWindowNotNull ()
+        {
+            var d = new Document ();
+            Assert.IsNotNull (d.Window);
+        }
+
+        [TestMethod]
+        public void DocumentBodyNotNull ()
+        {
+            var d = new Document ();
+            Assert.IsNotNull (d.Body);
+        }
+
+        [TestMethod]
+        public void WindowIdIsWindow ()
+        {
+            Assert.AreEqual ("window", new Window ().Id);
+        }
+
+        [TestMethod]
+        public void DocumentIdIsDocument ()
+        {
+            Assert.AreEqual ("document", new Document ().Id);
+        }
+
+        [TestMethod]
+        public void BodyIdIsDocumentBody ()
+        {
+            Assert.AreEqual ("document.body", new Body ().Id);
+        }
+
+        [TestMethod]
+        public void DocumentGetsWindowMessages ()
+        {
+            var d = new Document ();
+            var received = false;
+            d.MessageSent += m => {
+                received = m.TargetId == "window";
+            };
+            d.Window.Location = "http://google.com";
+            Assert.IsTrue (received);
+        }
+
+        [TestMethod]
+        public void ElementGetsWindowMessages ()
+        {
+            var b = new Button ();
+            var received = false;
+            b.MessageSent += m => {
+                received = m.TargetId == "window";
+            };
+            b.Document.Window.Location = "http://google.com";
+            Assert.IsTrue (received);
+        }
+
+        [TestMethod]
+        public void ElementGetsBodyMessages ()
+        {
+            var b = new Button ();
+            var received = false;
+            b.MessageSent += m => {
+                received = m.TargetId == "document.body";
+            };
+            b.Document.Body.Call ("foo");
+            Assert.IsTrue (received);
+        }
+    }
+}