michael@0: // Copyright (c) 2008 The Chromium Authors. All rights reserved.
michael@0: // Use of this source code is governed by a BSD-style license that can be
michael@0: // found in the LICENSE file.
michael@0: 
michael@0: #include "base/system_monitor.h"
michael@0: #include "base/logging.h"
michael@0: #include "base/message_loop.h"
michael@0: 
michael@0: namespace base {
michael@0: 
michael@0: #if defined(ENABLE_BATTERY_MONITORING)
michael@0: // The amount of time (in ms) to wait before running the initial
michael@0: // battery check.
michael@0: static int kDelayedBatteryCheckMs = 10 * 1000;
michael@0: #endif  // defined(ENABLE_BATTERY_MONITORING)
michael@0: 
michael@0: SystemMonitor::SystemMonitor()
michael@0:     : battery_in_use_(false),
michael@0:       suspended_(false) {
michael@0:   observer_list_ = new ObserverListThreadSafe<PowerObserver>();
michael@0: }
michael@0: 
michael@0: void SystemMonitor::ProcessPowerMessage(PowerEvent event_id) {
michael@0:   // Suppress duplicate notifications.  Some platforms may
michael@0:   // send multiple notifications of the same event.
michael@0:   switch (event_id) {
michael@0:     case POWER_STATE_EVENT:
michael@0:       {
michael@0:         bool on_battery = IsBatteryPower();
michael@0:         if (on_battery != battery_in_use_) {
michael@0:           battery_in_use_ = on_battery;
michael@0:           NotifyPowerStateChange();
michael@0:         }
michael@0:       }
michael@0:       break;
michael@0:     case RESUME_EVENT:
michael@0:       if (suspended_) {
michael@0:         suspended_ = false;
michael@0:         NotifyResume();
michael@0:       }
michael@0:       break;
michael@0:     case SUSPEND_EVENT:
michael@0:       if (!suspended_) {
michael@0:         suspended_ = true;
michael@0:         NotifySuspend();
michael@0:       }
michael@0:       break;
michael@0:   }
michael@0: }
michael@0: 
michael@0: void SystemMonitor::AddObserver(PowerObserver* obs) {
michael@0:   observer_list_->AddObserver(obs);
michael@0: }
michael@0: 
michael@0: void SystemMonitor::RemoveObserver(PowerObserver* obs) {
michael@0:   observer_list_->RemoveObserver(obs);
michael@0: }
michael@0: 
michael@0: void SystemMonitor::NotifyPowerStateChange() {
michael@0:   CHROMIUM_LOG(INFO) << "PowerStateChange: "
michael@0:                      << (BatteryPower() ? "On" : "Off") << " battery";
michael@0:   observer_list_->Notify(&PowerObserver::OnPowerStateChange, this);
michael@0: }
michael@0: 
michael@0: void SystemMonitor::NotifySuspend() {
michael@0:   CHROMIUM_LOG(INFO) << "Power Suspending";
michael@0:   observer_list_->Notify(&PowerObserver::OnSuspend, this);
michael@0: }
michael@0: 
michael@0: void SystemMonitor::NotifyResume() {
michael@0:   CHROMIUM_LOG(INFO) << "Power Resuming";
michael@0:   observer_list_->Notify(&PowerObserver::OnResume, this);
michael@0: }
michael@0: 
michael@0: void SystemMonitor::Start() {
michael@0: #if defined(ENABLE_BATTERY_MONITORING)
michael@0:   DCHECK(MessageLoop::current());  // Can't call start too early.
michael@0:   SystemMonitor* monitor = Get();
michael@0:   monitor->delayed_battery_check_.Start(
michael@0:       TimeDelta::FromMilliseconds(kDelayedBatteryCheckMs), monitor,
michael@0:       &SystemMonitor::BatteryCheck);
michael@0: #endif  // defined(ENABLE_BATTERY_MONITORING)
michael@0: }
michael@0: 
michael@0: void SystemMonitor::BatteryCheck() {
michael@0:   ProcessPowerMessage(SystemMonitor::POWER_STATE_EVENT);
michael@0: }
michael@0: 
michael@0: } // namespace base