Introduce very beginning of navigation

mojo/examples/embedded_app/embedded_app.cc

Index: mojo/examples/embedded_app/embedded_app.cc
diff --git a/mojo/examples/embedded_app/embedded_app.cc b/mojo/examples/embedded_app/embedded_app.cc
index adcef0264bff9231bc917eb596293548b2638457..003cb82d0f5f192d0ab160cda373895c8188aa16 100644
--- a/mojo/examples/embedded_app/embedded_app.cc
+++ b/mojo/examples/embedded_app/embedded_app.cc
@@ -4,8 +4,11 @@
 
 #include "base/basictypes.h"
 #include "base/bind.h"
+#include "base/logging.h"
+#include "base/strings/string_number_conversions.h"
 #include "mojo/examples/window_manager/window_manager.mojom.h"
 #include "mojo/public/cpp/application/application.h"
+#include "mojo/services/navigation/navigation.mojom.h"
 #include "mojo/services/public/cpp/view_manager/view.h"
 #include "mojo/services/public/cpp/view_manager/view_manager.h"
 #include "mojo/services/public/cpp/view_manager/view_manager_delegate.h"
@@ -13,6 +16,8 @@
 #include "mojo/services/public/cpp/view_manager/view_tree_node.h"
 #include "mojo/services/public/cpp/view_manager/view_tree_node_observer.h"
 #include "ui/events/event_constants.h"
+#include "url/gurl.h"
+#include "url/url_util.h"
 
 using mojo::view_manager::View;
 using mojo::view_manager::ViewManager;
@@ -23,28 +28,54 @@ using mojo::view_manager::ViewTreeNodeObserver;
 
 namespace mojo {
 namespace examples {
-namespace {
-
-const SkColor kColors[] = { SK_ColorYELLOW,
-                            SK_ColorRED,
-                            SK_ColorGREEN,
-                            SK_ColorMAGENTA };
-
-}  // namespace
 
 class EmbeddedApp : public Application,
                     public ViewManagerDelegate,
                     public ViewObserver,
                     public ViewTreeNodeObserver {
  public:
-  EmbeddedApp() {}
+  EmbeddedApp() : view_manager_(NULL) {
+    url::AddStandardScheme("mojo");
+  }
   virtual ~EmbeddedApp() {}
 
+  void SetNodeColor(uint32 node_id, SkColor color) {
+    pending_node_colors_[node_id] = color;
+    ProcessPendingNodeColor(node_id);
+  }
+
  private:
+  class Navigator : public InterfaceImpl<navigation::Navigator> {
+   public:
+    explicit Navigator(EmbeddedApp* app) : app_(app) {}
+   private:
+    virtual void Navigate(uint32 node_id,
+                          navigation::NavigationDetailsPtr details) OVERRIDE {
+      GURL url(details->url.To<std::string>());
+      if (!url.is_valid()) {
+        LOG(ERROR) << "URL is invalid.";
+        return;
+      }
+      // TODO(aa): Verify new URL is same origin as current origin.
+      SkColor color = 0x00;
+      if (!base::HexStringToUInt(url.path().substr(1), &color)) {
+        LOG(ERROR) << "Invalid URL, path not convertible to integer";
+        return;
+      }
+      app_->SetNodeColor(node_id, color);
+    }
+    EmbeddedApp* app_;
+    DISALLOW_COPY_AND_ASSIGN(Navigator);
+  };
+
   // Overridden from Application:
   virtual void Initialize() MOJO_OVERRIDE {
     ViewManager::Create(this, this);
+    // TODO(aa): Weird for embeddee to talk to embedder by URL. Seems like
+    // embedder should be able to specify the SP embeddee receives, then
+    // communication can be anonymous.
     ConnectTo<IWindowManager>("mojo:mojo_window_manager", &window_manager_);
+    AddService<Navigator>(this);
   }
 
   // Overridden from ViewManagerDelegate:
@@ -54,11 +85,14 @@ class EmbeddedApp : public Application,
     view->AddObserver(this);
     root->SetActiveView(view);
     root->AddObserver(this);
-    size_t index = view_manager->GetRoots().size() - 1;
-    view->SetColor(kColors[index % arraysize(kColors)]);
+
+    roots_[root->id()] = root;
+    ProcessPendingNodeColor(root->id());
   }
   virtual void OnRootRemoved(ViewManager* view_manager,
                              ViewTreeNode* root) OVERRIDE {
+    roots_.erase(root->id());
+
     std::map<ViewTreeNode*, View*>::const_iterator it =
         views_to_reap_.find(root);
     if (it != views_to_reap_.end())
@@ -81,9 +115,31 @@ class EmbeddedApp : public Application,
       views_to_reap_[node] = old_view;
   }
 
+  void ProcessPendingNodeColor(uint32 node_id) {
+    RootMap::iterator root = roots_.find(node_id);
+    if (root == roots_.end())
+      return;
+
+    PendingNodeColors::iterator color = pending_node_colors_.find(node_id);
+    if (color == pending_node_colors_.end())
+      return;
+
+    root->second->active_view()->SetColor(color->second);
+    pending_node_colors_.erase(color);
+  }
+
+
+  view_manager::ViewManager* view_manager_;
   IWindowManagerPtr window_manager_;
   std::map<ViewTreeNode*, View*> views_to_reap_;
 
+  typedef std::map<uint32, ViewTreeNode*> RootMap;
+  RootMap roots_;
+
+  // We can receive navigations for nodes we don't have yet.
+  typedef std::map<uint32, SkColor> PendingNodeColors;
+  PendingNodeColors pending_node_colors_;
+
   DISALLOW_COPY_AND_ASSIGN(EmbeddedApp);
 };