Add support for mapping node tree on the client.

mojo/services/public/cpp/view_manager/lib/view_manager_synchronizer.cc

Index: mojo/services/public/cpp/view_manager/lib/view_manager_synchronizer.cc
diff --git a/mojo/services/public/cpp/view_manager/lib/view_manager_synchronizer.cc b/mojo/services/public/cpp/view_manager/lib/view_manager_synchronizer.cc
index 5fe22b4cb9583454cb77dc23e3863b2632c26fcf..609a90e2f9100d9d811f954e1f83cccbd4dffd30 100644
--- a/mojo/services/public/cpp/view_manager/lib/view_manager_synchronizer.cc
+++ b/mojo/services/public/cpp/view_manager/lib/view_manager_synchronizer.cc
@@ -8,12 +8,17 @@
 #include "base/message_loop/message_loop.h"
 #include "mojo/public/cpp/bindings/allocation_scope.h"
 #include "mojo/public/interfaces/shell/shell.mojom.h"
+#include "mojo/services/public/cpp/view_manager/lib/view_manager_observer.h"
 #include "mojo/services/public/cpp/view_manager/lib/view_manager_private.h"
+#include "mojo/services/public/cpp/view_manager/lib/view_tree_node_private.h"
+#include "mojo/services/public/cpp/view_manager/util.h"
 
 namespace mojo {
 namespace services {
 namespace view_manager {
 
+const TransportNodeId kRootNodeId = 1;
+
 class ViewManagerTransaction {
  public:
   virtual ~ViewManagerTransaction() {}
@@ -21,6 +26,7 @@ class ViewManagerTransaction {
   void Commit() {
     DCHECK(!committed_);
     DoCommit();
+    synchronizer_->NotifyCommit();
     committed_ = true;
   }
 
@@ -31,13 +37,15 @@ class ViewManagerTransaction {
   void OnActionCompleted(bool success) {
     DCHECK(success);
     DoActionCompleted(success);
+    synchronizer_->NotifyCommitResponse(success);
     synchronizer_->RemoveFromPendingQueue(this);
   }
 
  protected:
   enum TransactionType {
-    // Node creation.
+    // Node creation and destruction.
     TYPE_CREATE_VIEW_TREE_NODE,
+    TYPE_DESTROY_VIEW_TREE_NODE,
     // Modifications to the hierarchy (addition of or removal of nodes from a
     // parent.)
     TYPE_HIERARCHY
@@ -60,8 +68,10 @@ class ViewManagerTransaction {
 
   IViewManager* service() { return synchronizer_->service_.get(); }
 
-  uint32_t MakeTransportId(uint16_t id) {
-    return (synchronizer_->connection_id_ << 16) | id;
+  TransportNodeId MakeTransportId(uint32_t id) {
+    if (id == kRootNodeId || HiWord(id) != 0)
+      return id;
+    return (synchronizer_->connection_id_ << 16) | LoWord(id);
   }
 
  private:
@@ -73,8 +83,7 @@ class ViewManagerTransaction {
   DISALLOW_COPY_AND_ASSIGN(ViewManagerTransaction);
 };
 
-class CreateViewTreeNodeTransaction
-    : public ViewManagerTransaction {
+class CreateViewTreeNodeTransaction : public ViewManagerTransaction {
  public:
   CreateViewTreeNodeTransaction(uint16_t node_id,
                                 ViewManagerSynchronizer* synchronizer)
@@ -90,7 +99,6 @@ class CreateViewTreeNodeTransaction
         base::Bind(&ViewManagerTransaction::OnActionCompleted,
                    base::Unretained(this)));
   }
-
   virtual void DoActionCompleted(bool success) OVERRIDE {
     // TODO(beng): Failure means we tried to create with an extant id for this
     //             connection. Figure out what to do.
@@ -101,6 +109,31 @@ class CreateViewTreeNodeTransaction
   DISALLOW_COPY_AND_ASSIGN(CreateViewTreeNodeTransaction);
 };
 
+class DestroyViewTreeNodeTransaction : public ViewManagerTransaction {
+ public:
+  DestroyViewTreeNodeTransaction(TransportNodeId node_id,
+                                 ViewManagerSynchronizer* synchronizer)
+      : ViewManagerTransaction(TYPE_DESTROY_VIEW_TREE_NODE, synchronizer),
+        node_id_(node_id) {}
+  virtual ~DestroyViewTreeNodeTransaction() {}
+
+ private:
+  // Overridden from ViewManagerTransaction:
+  virtual void DoCommit() OVERRIDE {
+    service()->DeleteNode(
+        node_id_,
+        change_id(),
+        base::Bind(&ViewManagerTransaction::OnActionCompleted,
+                   base::Unretained(this)));
+  }
+  virtual void DoActionCompleted(bool success) OVERRIDE {
+    // TODO(beng): recovery?
+  }
+
+  TransportNodeId node_id_;
+  DISALLOW_COPY_AND_ASSIGN(DestroyViewTreeNodeTransaction);
+};
+
 class HierarchyTransaction : public ViewManagerTransaction {
  public:
   enum HierarchyChangeType {
@@ -108,8 +141,8 @@ class HierarchyTransaction : public ViewManagerTransaction {
     TYPE_REMOVE
   };
   HierarchyTransaction(HierarchyChangeType hierarchy_change_type,
-                       uint16_t child_id,
-                       uint16_t parent_id,
+                       TransportNodeId child_id,
+                       TransportNodeId parent_id,
                        ViewManagerSynchronizer* synchronizer)
       : ViewManagerTransaction(TYPE_HIERARCHY, synchronizer),
         hierarchy_change_type_(hierarchy_change_type),
@@ -145,8 +178,8 @@ class HierarchyTransaction : public ViewManagerTransaction {
   }
 
   const HierarchyChangeType hierarchy_change_type_;
-  const uint16_t child_id_;
-  const uint16_t parent_id_;
+  const TransportNodeId child_id_;
+  const TransportNodeId parent_id_;
 
   DISALLOW_COPY_AND_ASSIGN(HierarchyTransaction);
 };
@@ -155,7 +188,7 @@ ViewManagerSynchronizer::ViewManagerSynchronizer(ViewManager* view_manager)
     : view_manager_(view_manager),
       connected_(false),
       connection_id_(0),
-      next_id_(0),
+      next_id_(1),
       next_change_id_(0) {
   InterfacePipe<services::view_manager::IViewManager, AnyInterface>
       view_manager_pipe;
@@ -169,13 +202,20 @@ ViewManagerSynchronizer::~ViewManagerSynchronizer() {
 }
 
 uint16_t ViewManagerSynchronizer::CreateViewTreeNode() {
-  uint16_t id = next_id_++;
+  uint16_t id = ++next_id_;
   pending_transactions_.push_back(new CreateViewTreeNodeTransaction(id, this));
   ScheduleSync();
   return id;
 }
 
-void ViewManagerSynchronizer::AddChild(uint16_t child_id, uint16_t parent_id) {
+void ViewManagerSynchronizer::DestroyViewTreeNode(TransportNodeId node_id) {
+  pending_transactions_.push_back(
+      new DestroyViewTreeNodeTransaction(node_id, this));
+  ScheduleSync();
+}
+
+void ViewManagerSynchronizer::AddChild(TransportNodeId child_id,
+                                       TransportNodeId parent_id) {
   pending_transactions_.push_back(
       new HierarchyTransaction(HierarchyTransaction::TYPE_ADD,
                                child_id,
@@ -184,8 +224,8 @@ void ViewManagerSynchronizer::AddChild(uint16_t child_id, uint16_t parent_id) {
   ScheduleSync();
 }
 
-void ViewManagerSynchronizer::RemoveChild(uint16_t child_id,
-                                          uint16_t parent_id) {
+void ViewManagerSynchronizer::RemoveChild(TransportNodeId child_id,
+                                          TransportNodeId parent_id) {
   pending_transactions_.push_back(
       new HierarchyTransaction(HierarchyTransaction::TYPE_REMOVE,
                                child_id,
@@ -194,6 +234,15 @@ void ViewManagerSynchronizer::RemoveChild(uint16_t child_id,
   ScheduleSync();
 }
 
+void ViewManagerSynchronizer::BuildNodeTree(
+    const Callback<void()>& callback) {
+  service_->GetNodeTree(
+      1,
+      base::Bind(&ViewManagerSynchronizer::OnTreeReceived,
+                 base::Unretained(this),
+                 callback));
+}
+
 ////////////////////////////////////////////////////////////////////////////////
 // ViewManagerSynchronizer, IViewManagerClient implementation:
 
@@ -201,6 +250,9 @@ void ViewManagerSynchronizer::OnConnectionEstablished(uint16 connection_id) {
   connected_ = true;
   connection_id_ = connection_id;
   ScheduleSync();
+  FOR_EACH_OBSERVER(ViewManagerObserver,
+                    *ViewManagerPrivate(view_manager_).observers(),
+                    OnViewManagerConnected(view_manager_));
 }
 
 void ViewManagerSynchronizer::OnNodeHierarchyChanged(uint32_t node,
@@ -250,12 +302,53 @@ uint32_t ViewManagerSynchronizer::GetNextChangeId() {
   return next_change_id_;
 }
 
+void ViewManagerSynchronizer::NotifyCommit() {
+  FOR_EACH_OBSERVER(ViewManagerObserver,
+                    *ViewManagerPrivate(view_manager_).observers(),
+                    OnCommit(view_manager_));
+}
+
+void ViewManagerSynchronizer::NotifyCommitResponse(bool success) {
+  FOR_EACH_OBSERVER(ViewManagerObserver,
+                    *ViewManagerPrivate(view_manager_).observers(),
+                    OnCommitResponse(view_manager_, success));
+}
+
 void ViewManagerSynchronizer::RemoveFromPendingQueue(
     ViewManagerTransaction* transaction) {
   DCHECK_EQ(transaction, pending_transactions_.front());
   pending_transactions_.erase(pending_transactions_.begin());
 }
 
+void ViewManagerSynchronizer::OnTreeReceived(
+    const Callback<void()>& callback,
+    const Array<INode>& nodes) {
+  std::vector<ViewTreeNode*> parents;
+  ViewTreeNode* root = NULL;
+  ViewTreeNode* last_node = NULL;
+  for (size_t i = 0; i < nodes.size(); ++i) {
+    if (last_node && nodes[i].parent_id() == last_node->id()) {
+      parents.push_back(last_node);
+    } else if (!parents.empty()) {
+      while (parents.back()->id() != nodes[i].parent_id())
+        parents.pop_back();
+    }
+    // We don't use the ctor that takes a ViewManager here, since it will call
+    // back to the service and attempt to create a new node.
+    ViewTreeNode* node = new ViewTreeNode;
+    ViewTreeNodePrivate private_node(node);
+    private_node.set_view_manager(view_manager_);
+    private_node.set_id(nodes[i].node_id());
+    if (!parents.empty())
+      ViewTreeNodePrivate(parents.back()).LocalAddChild(node);
+    if (!last_node)
+      root = node;
+    last_node = node;
+  }
+  ViewManagerPrivate(view_manager_).set_tree(root);
+  callback.Run();
+}
+
 }  // namespace view_manager
 }  // namespace services
 }  // namespace mojo