text: // Copyright 2014 The Chromium Authors. All rights reserved.
  // Use of this source code is governed by a BSD-style license that can be
  // found in the LICENSE file.
  
  #ifndef MOJO_SERVICES_VIEW_MANAGER_VIEW_MANAGER_SERVICE_IMPL_H_
  #define MOJO_SERVICES_VIEW_MANAGER_VIEW_MANAGER_SERVICE_IMPL_H_
  
  #include <set>
  #include <string>
  #include <vector>
  
  #include "base/basictypes.h"
  #include "base/containers/hash_tables.h"
  #include "base/memory/scoped_ptr.h"
  #include "mojo/services/public/interfaces/surfaces/surface_id.mojom.h"
  #include "mojo/services/public/interfaces/view_manager/view_manager.mojom.h"
  #include "mojo/services/view_manager/access_policy_delegate.h"
  #include "mojo/services/view_manager/ids.h"
  
  namespace gfx {
  class Rect;
  }
  
  namespace mojo {
  namespace service {
  
  class AccessPolicy;
  class ConnectionManager;
  class ServerView;
  
  // An instance of ViewManagerServiceImpl is created for every ViewManagerService
  // request. ViewManagerServiceImpl tracks all the state and views created by a
  // client. ViewManagerServiceImpl coordinates with ConnectionManager to update
  // the client (and internal state) as necessary.
  class ViewManagerServiceImpl : public ViewManagerService,
                                 public AccessPolicyDelegate {
   public:
    using ViewIdSet = base::hash_set<Id>;
  
    ViewManagerServiceImpl(ConnectionManager* connection_manager,
                           ConnectionSpecificId creator_id,
                           const std::string& creator_url,
                           const std::string& url,
                           const ViewId& root_id);
    ~ViewManagerServiceImpl() override;
  
    // |service_provider| is the ServiceProvider to pass to the client via
    // OnEmbed().
    void Init(ViewManagerClient* client,
              InterfaceRequest<ServiceProvider> service_provider);
  
    ConnectionSpecificId id() const { return id_; }
    ConnectionSpecificId creator_id() const { return creator_id_; }
    const std::string& url() const { return url_; }
  
    ViewManagerClient* client() { return client_; }
  
    // Returns the View with the specified id.
    ServerView* GetView(const ViewId& id) {
      return const_cast<ServerView*>(
          const_cast<const ViewManagerServiceImpl*>(this)->GetView(id));
    }
    const ServerView* GetView(const ViewId& id) const;
  
    // Returns true if this connection's root is |id|.
    bool IsRoot(const ViewId& id) const;
  
    // Returns the id of the root node. This is null if the root has been
    // destroyed but the connection is still valid.
    const ViewId* root() const { return root_.get(); }
  
    // Invoked when a connection is about to be destroyed.
    void OnWillDestroyViewManagerServiceImpl(ViewManagerServiceImpl* connection);
  
    // These functions are synchronous variants of those defined in the mojom. The
    // ViewManagerService implementations all call into these. See the mojom for
    // details.
    ErrorCode CreateView(const ViewId& view_id);
    bool AddView(const ViewId& parent_id, const ViewId& child_id);
    std::vector<const ServerView*> GetViewTree(const ViewId& view_id) const;
    bool SetViewVisibility(const ViewId& view_id, bool visible);
    bool Embed(const std::string& url,
               const ViewId& view_id,
               InterfaceRequest<ServiceProvider> service_provider);
  
    // The following methods are invoked after the corresponding change has been
    // processed. They do the appropriate bookkeeping and update the client as
    // necessary.
    void ProcessViewBoundsChanged(const ServerView* view,
                                  const gfx::Rect& old_bounds,
                                  const gfx::Rect& new_bounds,
                                  bool originated_change);
    void ProcessWillChangeViewHierarchy(const ServerView* view,
                                        const ServerView* new_parent,
                                        const ServerView* old_parent,
                                        bool originated_change);
    void ProcessViewPropertyChanged(const ServerView* view,
                                    const std::string& name,
                                    const std::vector<uint8_t>* new_data,
                                    bool originated_change);
    void ProcessViewHierarchyChanged(const ServerView* view,
                                     const ServerView* new_parent,
                                     const ServerView* old_parent,
                                     bool originated_change);
    void ProcessViewReorder(const ServerView* view,
                            const ServerView* relative_view,
                            OrderDirection direction,
                            bool originated_change);
    void ProcessViewDeleted(const ViewId& view, bool originated_change);
    void ProcessWillChangeViewVisibility(const ServerView* view,
                                         bool originated_change);
    void ProcessViewPropertiesChanged(const ServerView* view,
                                      bool originated_change);
  
   private:
    typedef std::map<ConnectionSpecificId, ServerView*> ViewMap;
  
    bool IsViewKnown(const ServerView* view) const;
  
    // These functions return true if the corresponding mojom function is allowed
    // for this connection.
    bool CanReorderView(const ServerView* view,
                        const ServerView* relative_view,
                        OrderDirection direction) const;
  
    // Deletes a view owned by this connection. Returns true on success. |source|
    // is the connection that originated the change.
    bool DeleteViewImpl(ViewManagerServiceImpl* source, ServerView* view);
  
    // If |view| is known (in |known_views_|) does nothing. Otherwise adds |view|
    // to |views|, marks |view| as known and recurses.
    void GetUnknownViewsFrom(const ServerView* view,
                             std::vector<const ServerView*>* views);
  
    // Removes |view| and all its descendants from |known_views_|. This does not
    // recurse through views that were created by this connection. All views owned
    // by this connection are added to |local_views|.
    void RemoveFromKnown(const ServerView* view,
                         std::vector<ServerView*>* local_views);
  
    // Resets the root of this connection.
    void RemoveRoot();
  
    void RemoveChildrenAsPartOfEmbed(const ViewId& view_id);
  
    // Converts View(s) to ViewData(s) for transport. This assumes all the views
    // are valid for the client. The parent of views the client is not allowed to
    // see are set to NULL (in the returned ViewData(s)).
    Array<ViewDataPtr> ViewsToViewDatas(
        const std::vector<const ServerView*>& views);
    ViewDataPtr ViewToViewData(const ServerView* view);
  
    // Implementation of GetViewTree(). Adds |view| to |views| and recurses if
    // CanDescendIntoViewForViewTree() returns true.
    void GetViewTreeImpl(const ServerView* view,
                         std::vector<const ServerView*>* views) const;
  
    // Notify the client if the drawn state of any of the roots changes.
    // |view| is the view that is changing to the drawn state |new_drawn_value|.
    void NotifyDrawnStateChanged(const ServerView* view, bool new_drawn_value);
  
    // Deletes all Views we own.
    void DestroyViews();
  
    // ViewManagerService:
    void CreateView(Id transport_view_id,
                    const Callback<void(ErrorCode)>& callback) override;
    void DeleteView(Id transport_view_id,
                    const Callback<void(bool)>& callback) override;
    void AddView(Id parent_id,
                 Id child_id,
                 const Callback<void(bool)>& callback) override;
    void RemoveViewFromParent(Id view_id,
                              const Callback<void(bool)>& callback) override;
    void ReorderView(Id view_id,
                     Id relative_view_id,
                     OrderDirection direction,
                     const Callback<void(bool)>& callback) override;
    void GetViewTree(Id view_id,
                     const Callback<void(Array<ViewDataPtr>)>& callback) override;
    void SetViewSurfaceId(Id view_id,
                          SurfaceIdPtr surface_id,
                          const Callback<void(bool)>& callback) override;
    void SetViewBounds(Id view_id,
                       RectPtr bounds,
                       const Callback<void(bool)>& callback) override;
    void SetViewVisibility(Id view_id,
                           bool visible,
                           const Callback<void(bool)>& callback) override;
    void SetViewProperty(Id view_id,
                         const String& name,
                         Array<uint8_t> value,
                         const Callback<void(bool)>& callback) override;
    void Embed(const String& url,
               Id view_id,
               InterfaceRequest<ServiceProvider> service_provider,
               const Callback<void(bool)>& callback) override;
  
    // AccessPolicyDelegate:
    bool IsRootForAccessPolicy(const ViewId& id) const override;
    bool IsViewKnownForAccessPolicy(const ServerView* view) const override;
    bool IsViewRootOfAnotherConnectionForAccessPolicy(
        const ServerView* view) const override;
  
    ConnectionManager* connection_manager_;
  
    // Id of this connection as assigned by ConnectionManager.
    const ConnectionSpecificId id_;
  
    // URL this connection was created for.
    const std::string url_;
  
    // ID of the connection that created us. If 0 it indicates either we were
    // created by the root, or the connection that created us has been destroyed.
    ConnectionSpecificId creator_id_;
  
    // The URL of the app that embedded the app this connection was created for.
    const std::string creator_url_;
  
    ViewManagerClient* client_;
  
    scoped_ptr<AccessPolicy> access_policy_;
  
    // The views created by this connection. This connection owns these objects.
    ViewMap view_map_;
  
    // The set of views that has been communicated to the client.
    ViewIdSet known_views_;
  
    // The root of this connection. This is a scoped_ptr to reinforce the
    // connection may have no root. A connection has no root if either the root
    // is destroyed or Embed() is invoked on the root.
    scoped_ptr<ViewId> root_;
  
    DISALLOW_COPY_AND_ASSIGN(ViewManagerServiceImpl);
  };
  
  }  // namespace service
  }  // namespace mojo
  
  #endif  // MOJO_SERVICES_VIEW_MANAGER_VIEW_MANAGER_SERVICE_IMPL_H_
  