[PresentationAPI] Implementing start/joinSession from WebPresentationClient to PresentationService.

content/renderer/presentation/presentation_dispatcher.cc

 // 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.
 
 #include "content/renderer/presentation/presentation_dispatcher.h"
 
 #include "content/common/presentation/presentation_service.mojom.h"
 #include "content/public/common/service_registry.h"
 #include "content/public/renderer/render_frame.h"
+#include "content/renderer/presentation/presentation_session_client.h"
+#include "third_party/WebKit/public/platform/WebString.h"
 #include "third_party/WebKit/public/platform/modules/presentation/WebPresentationController.h"
+#include "third_party/WebKit/public/platform/modules/presentation/WebPresentationError.h"
+
+namespace {
+
+blink::WebPresentationError::ErrorType GetWebPresentationErrorTypeFromMojo(
+    presentation::PresentationErrorType mojoErrorType) {
+  switch (mojoErrorType) {
+    case presentation::PRESENTATION_ERROR_TYPE_NO_AVAILABLE_SCREENS:
+      return blink::WebPresentationError::ErrorTypeNoAvailableScreens;
+    case presentation::PRESENTATION_ERROR_TYPE_SESSION_REQUEST_CANCELLED:
+      return blink::WebPresentationError::ErrorTypeSessionRequestCancelled;
+    case presentation::PRESENTATION_ERROR_TYPE_NO_PRESENTATION_FOUND:
+      return blink::WebPresentationError::ErrorTypeNoPresentationFound;
+    case presentation::PRESENTATION_ERROR_TYPE_UNKNOWN:
+    default:
+      return blink::WebPresentationError::ErrorTypeUnknown;
+  }
+}
+
+}  // namespace
 
 namespace content {
 
 PresentationDispatcher::PresentationDispatcher(RenderFrame* render_frame)
     : RenderFrameObserver(render_frame),
       controller_(nullptr) {
 }
 
 PresentationDispatcher::~PresentationDispatcher() {
   // Controller should be destroyed before the dispatcher when frame is
@@ skipping 16 matching lines @@
   if (watched) {
     presentation_service_->GetScreenAvailability(
         mojo::String(),
         base::Bind(&PresentationDispatcher::OnScreenAvailabilityChanged,
                  base::Unretained(this)));
   } else {
     presentation_service_->OnScreenAvailabilityListenerRemoved();
   }
 }
 
+void PresentationDispatcher::startSession(
+    const blink::WebString& presentationUrl,
+    const blink::WebString& presentationId,
+    blink::WebPresentationSessionClientCallbacks* callback) {
+  ConnectToPresentationServiceIfNeeded();
+  presentation_service_->StartSession(
+      presentationUrl.utf8(),
+      presentationId.utf8(),
+      base::Bind(&PresentationDispatcher::OnSessionCreated,
+          base::Unretained(this),
+          base::Owned(callback)));
+}
+
+void PresentationDispatcher::joinSession(
+    const blink::WebString& presentationUrl,
+    const blink::WebString& presentationId,
+    blink::WebPresentationSessionClientCallbacks* callback) {
+  ConnectToPresentationServiceIfNeeded();
+  presentation_service_->JoinSession(

[mlamouri (slow - plz ping), 2015/02/26 22:24:26]

You don't have to apply that change but I wonder if we could do something like
this:
presentation::PresentationServicePtr& GetPresentationService() {
  if (!presentation_service_.get())
    render_frame()->GetServiceRegistry()->ConnectToRemoteService(
        &presentation_service_);

  return presentationt_service_;
}

Then you can do things like:
GetPresentationService()->JoinSession(...);

WDYT?

[whywhat, 2015/02/27 14:44:45]

Would look a little better but then you can't really return the pointer by value
and returning by reference is somewhat against the style guide. A smart pointer
would be nice  I guess but I'll leave it out of this CL.

+      presentationUrl.utf8(),
+      presentationId.utf8(),
+      base::Bind(&PresentationDispatcher::OnSessionCreated,
+          base::Unretained(this),
+          base::Owned(callback)));
+}
+
 void PresentationDispatcher::OnScreenAvailabilityChanged(bool available) {
   if (!controller_)
     return;
 
   // Reset the callback to get the next event.
   updateAvailableChangeWatched(controller_->isAvailableChangeWatched());
 
   controller_->didChangeAvailability(available);
 }
 
+void PresentationDispatcher::OnSessionCreated(
+    blink::WebPresentationSessionClientCallbacks* callback,
+    presentation::PresentationSessionInfoPtr session_info,
+    presentation::PresentationErrorPtr error) {
+  if (!callback)
+    return;

[mlamouri (slow - plz ping), 2015/02/26 22:24:26]

How could that happen? If it's not expected, please add a DCHECK.

[whywhat, 2015/02/27 14:44:45]

Done.

+  if (!error.is_null()) {
+    DCHECK(session_info.is_null());
+    callback->onError(new blink::WebPresentationError(
+        GetWebPresentationErrorTypeFromMojo(error->errorType),
+        blink::WebString::fromUTF8(error->message)));
+    return;
+  }
+
+  DCHECK(!session_info.is_null());
+  PresentationSessionDispatcher* session_dispatcher =
+      new PresentationSessionDispatcher(session_info.Pass());
+  presentation_sessions_.push_back(session_dispatcher);
+  callback->onSuccess(new PresentationSessionClient(session_dispatcher));
+}
+
 void PresentationDispatcher::ConnectToPresentationServiceIfNeeded() {
   if (presentation_service_.get())
     return;
 
   render_frame()->GetServiceRegistry()->ConnectToRemoteService(
       &presentation_service_);
 }
 
 }  // namespace content