Wake Lock API implementation (Chromium part)

content/browser/wake_lock/wake_lock_service_context.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/browser/wake_lock/wake_lock_service_context.h"
+
+#include "base/bind.h"
+#include "content/browser/frame_host/frame_tree_node.h"
+#include "content/browser/frame_host/render_frame_host_impl.h"
+#include "content/browser/power_save_blocker_impl.h"
+#include "content/public/browser/browser_thread.h"
+#include "content/public/browser/power_save_blocker.h"
+#include "content/public/common/service_registry.h"
+
+namespace content {
+
+WakeLockServiceContext::WakeLockServiceContext(WebContents* web_contents)
+    : WebContentsObserver(web_contents),
+      weak_factory_(this) {
+}
+
+WakeLockServiceContext::~WakeLockServiceContext() {
+}
+
+void WakeLockServiceContext::CreateService(
+    int frame_id,
+    mojo::InterfaceRequest<WakeLockService> request) {
+  new WakeLockServiceImpl(weak_factory_.GetWeakPtr(),
+                          frame_id,
+                          request.Pass());
+}
+
+void WakeLockServiceContext::RenderFrameDeleted(
+    RenderFrameHost* render_frame_host) {
+  CancelWakeLockForRFH(render_frame_host);
+}
+
+void WakeLockServiceContext::RenderFrameHostChanged(RenderFrameHost* old_host,
+                                                    RenderFrameHost* new_host) {
+  CancelWakeLockForRFH(old_host);
+}
+
+void WakeLockServiceContext::RequestWakeLock(int frame_id) {
+  DCHECK_CURRENTLY_ON(BrowserThread::UI);
+  frames_requesting_lock_.insert(frame_id);
+  UpdateWakeLock();
+}
+
+void WakeLockServiceContext::CancelWakeLock(int frame_id) {
+  DCHECK_CURRENTLY_ON(BrowserThread::UI);
+  frames_requesting_lock_.erase(frame_id);
+  UpdateWakeLock();
+}
+
+bool WakeLockServiceContext::HasWakeLockForTests() const {
+  return wake_lock_;
+}
+
+void WakeLockServiceContext::CancelWakeLockForRFH(
+    RenderFrameHost* render_frame_host) {
+  if (!render_frame_host)
+    return;
+
+  RenderFrameHostImpl* rfh_impl =
+      static_cast<RenderFrameHostImpl*>(render_frame_host);
+  CancelWakeLock(rfh_impl->frame_tree_node()->frame_tree_node_id());
+}
+
+void WakeLockServiceContext::CreateWakeLock() {
+  DCHECK(!wake_lock_);
+  wake_lock_ = PowerSaveBlocker::Create(
+      PowerSaveBlocker::kPowerSaveBlockPreventDisplaySleep,
+      PowerSaveBlocker::kReasonOther,
+      "Wake Lock API");
+
+  // On Android, additionaly associate the blocker with this WebContents.
+#if defined(OS_ANDROID)
+  DCHECK(web_contents());
+
+  static_cast<PowerSaveBlockerImpl*>(wake_lock_.get())->InitDisplaySleepBlocker(
+      web_contents());
+#endif
+}
+
+void WakeLockServiceContext::RemoveWakeLock() {
+  DCHECK(wake_lock_);
+  wake_lock_.reset();
+}
+
+void WakeLockServiceContext::UpdateWakeLock() {
+  if (!frames_requesting_lock_.empty()) {
+    if (!wake_lock_)
+      CreateWakeLock();
+  } else {
+    if (wake_lock_)
+      RemoveWakeLock();
+  }
+}
+
+}  // namespace content