Support listening for available screens for multiple presentation urls in the same frame

content/browser/presentation/presentation_service_impl.cc

Index: content/browser/presentation/presentation_service_impl.cc
diff --git a/content/browser/presentation/presentation_service_impl.cc b/content/browser/presentation/presentation_service_impl.cc
index c106757562029e1620064e9d14833b0edf61ab85..02e2773080adf269686f341838ed690469a7c15e 100644
--- a/content/browser/presentation/presentation_service_impl.cc
+++ b/content/browser/presentation/presentation_service_impl.cc
@@ -5,29 +5,200 @@
 #include "content/browser/presentation/presentation_service_impl.h"
 
 #include "base/logging.h"
+#include "content/public/browser/content_browser_client.h"
+#include "content/public/browser/navigation_details.h"
+#include "content/public/browser/render_frame_host.h"
+#include "content/public/browser/render_process_host.h"
+#include "content/public/browser/web_contents.h"
+#include "content/public/common/content_client.h"
+#include "content/public/common/frame_navigate_params.h"
 
 namespace content {
 
-PresentationServiceImpl::PresentationServiceImpl() {
+PresentationServiceImpl::PresentationServiceImpl(
+    RenderFrameHost* render_frame_host,
+    WebContents* web_contents,
+    PresentationServiceDelegate* delegate)
+    : WebContentsObserver(web_contents),
+      render_frame_host_(render_frame_host),
+      delegate_(delegate) {
+  DCHECK(render_frame_host_);
+  DCHECK(web_contents);
+  VLOG(2) << "PresentationServiceImpl: "
+          << render_frame_host_->GetProcess()->GetID() << ", "
+          << render_frame_host_->GetRoutingID();
+  if (delegate_)
+    delegate_->AddObserver(this);
 }
 
 PresentationServiceImpl::~PresentationServiceImpl() {
+  if (delegate_)
+    delegate_->RemoveObserver(this);
 }
 
 // static
 void PresentationServiceImpl::CreateMojoService(
+    RenderFrameHost* render_frame_host,
     mojo::InterfaceRequest<presentation::PresentationService> request) {
-  mojo::BindToRequest(new PresentationServiceImpl(), &request);
+  VLOG(2) << "PresentationServiceImpl::CreateService";
+  WebContents* web_contents =
+      WebContents::FromRenderFrameHost(render_frame_host);
+  DCHECK(web_contents);
+
+  mojo::BindToRequest(
+      new PresentationServiceImpl(
+          render_frame_host,
+          web_contents,
+          GetContentClient()->browser()->GetPresentationServiceDelegate(
+              web_contents)),
+          &request);
+}
+
+void PresentationServiceImpl::OnConnectionError() {
+  VLOG(1) << "PresentationServiceImpl::OnConnectionError: "
+          << render_frame_host_->GetProcess()->GetID() << ", "
+          << render_frame_host_->GetRoutingID();
 }
 
 void PresentationServiceImpl::GetScreenAvailability(
     const mojo::String& presentation_url,
-    const AvailabilityCallback& callback) {
-  NOTIMPLEMENTED();
+    const ScreenAvailabilityMojoCallback& callback) {
+  VLOG(2) << "PresentationServiceImpl::GetScreenAvailability";
+  if (!delegate_)
+    return;
+
+  const std::string& presentation_url_str = !presentation_url.is_null() ?
+      presentation_url.get() : default_presentation_url_;
+
+  // GetScreenAvailability() is called with no URL and there is no default
+  // Presentation URL.
+  if (presentation_url_str.empty())
+    return;
+
+  auto it = availability_contexts_.find(presentation_url_str);
+  if (it == availability_contexts_.end()) {
+    linked_ptr<ScreenAvailabilityContext> context(
+        new ScreenAvailabilityContext(presentation_url_str));
+
+    if (!delegate_->AddScreenAvailabilityListener(
+        render_frame_host_->GetProcess()->GetID(),
+        render_frame_host_->GetRoutingID(),
+        context.get())) {
+      VLOG(1) << "AddScreenAvailabilityListener failed. Ignoring request.";
+      return;
+    }
+
+    it = availability_contexts_.insert(
+        std::make_pair(presentation_url_str, context)).first;
+  }
+
+  it->second->CallbackReceived(callback);
 }
 
 void PresentationServiceImpl::OnScreenAvailabilityListenerRemoved() {
   NOTIMPLEMENTED();
 }
 
+void PresentationServiceImpl::DidNavigateAnyFrame(
+    content::RenderFrameHost* render_frame_host,
+    const content::LoadCommittedDetails& details,
+    const content::FrameNavigateParams& params) {
+  VLOG(2) << "PresentationServiceImpl::DidNavigateAnyFrame";
+  if (render_frame_host_ != render_frame_host)
+    return;
+
+  std::string prev_url_host = details.previous_url.host();
+  std::string curr_url_host = params.url.host();
+
+  // If a frame navigation is in-page (e.g. navigating to a fragment in
+  // same page) then we do not unregister listeners.
+  bool in_page_navigation = details.is_in_page ||
+      details.type == content::NAVIGATION_TYPE_IN_PAGE;
+
+  VLOG(2) << "DidNavigateAnyFrame: "
+          << "prev host: " << prev_url_host << ", curr host: " << curr_url_host
+          << ", in_page_navigation: " << in_page_navigation;
+
+  if (in_page_navigation)
+    return;
+
+  // Unregister all sources if the frame actually navigated.
+  RemoveAllListeners();
+}
+
+void PresentationServiceImpl::RenderFrameDeleted(
+    content::RenderFrameHost* render_frame_host) {
+  VLOG(2) << "PresentationServiceImpl::RenderFrameDeleted";
+  if (render_frame_host_ != render_frame_host)
+    return;
+
+  // RenderFrameDeleted means this object is getting deleted soon.
+  RemoveAllListeners();
+}
+
+void PresentationServiceImpl::RemoveAllListeners() {
+  VLOG(2) << "PresentationServiceImpl::RemoveAllListeners";
+  if (!delegate_)
+    return;
+
+  delegate_->RemoveAllScreenAvailabilityListeners(
+        render_frame_host_->GetProcess()->GetID(),
+        render_frame_host_->GetRoutingID());
+
+  availability_contexts_.clear();
+}
+
+void PresentationServiceImpl::OnDelegateDestroyed() {
+  VLOG(2) << "PresentationServiceImpl::OnDelegateDestroyed";
+  delegate_ = nullptr;
+}
+
+PresentationServiceImpl::ScreenAvailabilityContext::ScreenAvailabilityContext(
+    const std::string& presentation_url)
+    : presentation_url_(presentation_url) {
+}
+
+PresentationServiceImpl::ScreenAvailabilityContext::
+~ScreenAvailabilityContext() {
+}
+
+void PresentationServiceImpl::ScreenAvailabilityContext::CallbackReceived(
+    const ScreenAvailabilityMojoCallback& callback) {
+  // NOTE: This will overwrite previously registered callback if any.
+  if (!available_ptr_) {
+    // No results yet, store callback for later invocation.
+    callback_ptr_.reset(new ScreenAvailabilityMojoCallback(callback));
+  } else {
+    // Run callback now, reset result.
+    // There shouldn't be any callbacks stored in this scenario.
+    DCHECK(!callback_ptr_);
+    callback.Run(*available_ptr_);
+    Reset();
+  }
+}
+
+void PresentationServiceImpl::ScreenAvailabilityContext::Reset() {
+  callback_ptr_.reset();
+  available_ptr_.reset();
+}
+
+std::string PresentationServiceImpl::ScreenAvailabilityContext
+    ::GetPresentationUrl() const {
+  return presentation_url_;
+}
+
+void PresentationServiceImpl::ScreenAvailabilityContext
+    ::OnScreenAvailabilityChanged(bool available) {
+  if (!callback_ptr_) {
+    // No callback, stash the result for now.
+    available_ptr_.reset(new bool(available));
+  } else {
+    // Invoke callback and erase it.
+    // There shouldn't be any result stored in this scenario.
+    DCHECK(!available_ptr_);
+    callback_ptr_->Run(available);
+    Reset();
+  }
+}
+
 }  // namespace content