[Presentation API] Handle multiple Presentation URLs in PresentationRequest::getAvailability()

content/renderer/presentation/presentation_dispatcher.h

 // Copyright 2015 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 CONTENT_RENDERER_PRESENTATION_PRESENTATION_DISPATCHER_H_
 #define CONTENT_RENDERER_PRESENTATION_PRESENTATION_DISPATCHER_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 29 matching lines @@
 // Blink. It forwards the calls to the Mojo PresentationService.
 class CONTENT_EXPORT PresentationDispatcher
     : public RenderFrameObserver,
       public NON_EXPORTED_BASE(blink::WebPresentationClient),
       public NON_EXPORTED_BASE(blink::mojom::PresentationServiceClient) {
  public:
   explicit PresentationDispatcher(RenderFrame* render_frame);
   ~PresentationDispatcher() override;
 
  private:
+  friend class PresentationDispatcherTest;
   struct SendMessageRequest {
     SendMessageRequest(blink::mojom::PresentationSessionInfoPtr session_info,
                        blink::mojom::ConnectionMessagePtr message);
     ~SendMessageRequest();
 
     blink::mojom::PresentationSessionInfoPtr session_info;
     blink::mojom::ConnectionMessagePtr message;
   };
 
   static SendMessageRequest* CreateSendTextMessageRequest(
@@ skipping 29 matching lines @@
                        size_t length) override;
   void sendBlobData(const blink::WebURL& presentationUrl,
                     const blink::WebString& presentationId,
                     const uint8_t* data,
                     size_t length) override;
   void closeSession(const blink::WebURL& presentationUrl,
                     const blink::WebString& presentationId) override;
   void terminateSession(const blink::WebURL& presentationUrl,
                         const blink::WebString& presentationId) override;
   void getAvailability(
       const blink::WebVector<blink::WebURL>& availabilityUrl,

[mark a. foltz, 2016/12/23 01:04:22]

Nit: availabilityUrls

[zhaobin, 2016/12/29 18:48:38]

Done.

       std::unique_ptr<blink::WebPresentationAvailabilityCallbacks> callbacks)
       override;
   void startListening(blink::WebPresentationAvailabilityObserver*) override;
   void stopListening(blink::WebPresentationAvailabilityObserver*) override;
   void setDefaultPresentationUrls(
       const blink::WebVector<blink::WebURL>& presentationUrls) override;
 
   // RenderFrameObserver implementation.
   void DidCommitProvisionalLoad(
       bool is_new_navigation,
@@ skipping 23 matching lines @@
   void OnReceiverConnectionAvailable(
       blink::mojom::PresentationSessionInfoPtr) override;
 
   // Call to PresentationService to send the message in |request|.
   // |session_info| and |message| of |reuqest| will be consumed.
   // |HandleSendMessageRequests| will be invoked after the send is attempted.
   void DoSendMessage(SendMessageRequest* request);
   void HandleSendMessageRequests(bool success);
 
   void ConnectToPresentationServiceIfNeeded();
+  void SetPresentationServiceForTest(
+      blink::mojom::PresentationServicePtr presentation_service);
 
   void UpdateListeningState();
 
   // Used as a weak reference. Can be null since lifetime is bound to the frame.
   blink::WebPresentationController* controller_;
   blink::WebPresentationReceiver* receiver_;
   blink::mojom::PresentationServicePtr presentation_service_;
   mojo::Binding<blink::mojom::PresentationServiceClient> binding_;
 
   // Message requests are queued here and only one message at a time is sent
   // over mojo channel.
   using MessageRequestQueue = std::queue<std::unique_ptr<SendMessageRequest>>;
   MessageRequestQueue message_request_queue_;
 
   enum class ListeningState {
     INACTIVE,
     WAITING,
     ACTIVE,
   };
 
+  enum class ScreenAvailability {
+    UNKNOWN,
+    AVAILABLE,
+    UNAVAILABLE,
+    UNSUPPORTED

[mark a. foltz, 2016/12/23 01:04:22]

I don't recall exactly why we have an API in the dispatcher to report that a
specific URL is not supported for screen availability monitoring.  I would
normally think this is a property of the entire browser (for example a setting
or low battery mode) but this does give the embedder maximum flexibility.

I'm not sure how we should report overall availability for a request when some
of the URLs are unsupported...  maybe handle this the same as UNKNOWN?

[zhaobin, 2016/12/29 18:48:38]

Done.

+  };
+
   using AvailabilityCallbacksMap =
       IDMap<std::unique_ptr<blink::WebPresentationAvailabilityCallbacks>>;
   using AvailabilityObserversSet =
       std::set<blink::WebPresentationAvailabilityObserver*>;
 
   // Tracks status of presentation displays availability for |availability_url|.
   struct AvailabilityStatus {
-    explicit AvailabilityStatus(const GURL& availability_url);
+    explicit AvailabilityStatus(const std::vector<GURL>& availability_urls);
     ~AvailabilityStatus();
 
-    const GURL url;
-    bool last_known_availability;
-    ListeningState listening_state;
+    const std::vector<GURL> urls;
     AvailabilityCallbacksMap availability_callbacks;
     AvailabilityObserversSet availability_observers;
   };
 
   // Map of AvailabilityStatus for known URLs.
-  std::map<GURL, std::unique_ptr<AvailabilityStatus>>
+  std::map<std::vector<GURL>, std::unique_ptr<AvailabilityStatus>>

[mark a. foltz, 2016/12/23 01:04:22]

Is it okay to use a container as a map key? 

I usually think of availability as applying to a specific URL.

[zhaobin, 2016/12/29 18:48:38]

Code removed.

       availability_status_;
 
+  // Map of ScreenAvailability for known URL.
+  std::map<GURL, ScreenAvailability> screen_availability_;
+
+  // Map of ListeningState for known URL.
+  std::map<GURL, ListeningState> url_listening_state_;

[mark a. foltz, 2016/12/23 01:04:22]

Can we combine these with AvailabilityStatus?

[zhaobin, 2016/12/29 18:48:38]

Code removed.

+
   // Updates the listening state of availability for |status| and notifies the
   // client.
   void UpdateListeningState(AvailabilityStatus* status);
 
+  // Called when all urls in |status| reports ScreenAvailability::UNSUPPORTED.
+  void OnScreenAvailabilityNotSupported(AvailabilityStatus* status);
+
+  // Called when all urls in |status| reports their screen availability.
+  void OnScreenAvailabilityUpdated(AvailabilityStatus* status, bool available);
+
+  void OnScreenAvailabilityUpdated(const GURL& url, ScreenAvailability);
+
+  // Returns UNKNOWN if any url in |urls| has screen availability UNKNOWN.
+  // Returns AVAILABLE if at least one url in |urls| has screen availability
+  // AVAILABLE, and no url has screen availability UNKNOWN;
+  // Returns UNAVAILABLE is at least one url in |urls| has screen availability
+  // UNAVAILABLE, and no url has screen availability UNKNOWN or AVAILABLE;
+  // Returns UNSUPPORTED if all urls in |urls| have screen availability
+  // UNSUPPORTED.
+  PresentationDispatcher::ScreenAvailability GetRequestAvailability(
+      const std::vector<GURL>& urls);
+
   DISALLOW_COPY_AND_ASSIGN(PresentationDispatcher);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_PRESENTATION_PRESENTATION_DISPATCHER_H_