michael@0: /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #include <limits>
michael@0: #include "BatteryManager.h"
michael@0: #include "Constants.h"
michael@0: #include "mozilla/DOMEventTargetHelper.h"
michael@0: #include "mozilla/Hal.h"
michael@0: #include "mozilla/Preferences.h"
michael@0: #include "mozilla/dom/BatteryManagerBinding.h"
michael@0: #include "nsIDOMClassInfo.h"
michael@0: 
michael@0: /**
michael@0:  * We have to use macros here because our leak analysis tool things we are
michael@0:  * leaking strings when we have |static const nsString|. Sad :(
michael@0:  */
michael@0: #define LEVELCHANGE_EVENT_NAME           NS_LITERAL_STRING("levelchange")
michael@0: #define CHARGINGCHANGE_EVENT_NAME        NS_LITERAL_STRING("chargingchange")
michael@0: #define DISCHARGINGTIMECHANGE_EVENT_NAME NS_LITERAL_STRING("dischargingtimechange")
michael@0: #define CHARGINGTIMECHANGE_EVENT_NAME    NS_LITERAL_STRING("chargingtimechange")
michael@0: 
michael@0: namespace mozilla {
michael@0: namespace dom {
michael@0: namespace battery {
michael@0: 
michael@0: BatteryManager::BatteryManager(nsPIDOMWindow* aWindow)
michael@0:   : DOMEventTargetHelper(aWindow)
michael@0:   , mLevel(kDefaultLevel)
michael@0:   , mCharging(kDefaultCharging)
michael@0:   , mRemainingTime(kDefaultRemainingTime)
michael@0: {
michael@0: }
michael@0: 
michael@0: void
michael@0: BatteryManager::Init()
michael@0: {
michael@0:   hal::RegisterBatteryObserver(this);
michael@0: 
michael@0:   hal::BatteryInformation batteryInfo;
michael@0:   hal::GetCurrentBatteryInformation(&batteryInfo);
michael@0: 
michael@0:   UpdateFromBatteryInfo(batteryInfo);
michael@0: }
michael@0: 
michael@0: void
michael@0: BatteryManager::Shutdown()
michael@0: {
michael@0:   hal::UnregisterBatteryObserver(this);
michael@0: }
michael@0: 
michael@0: JSObject*
michael@0: BatteryManager::WrapObject(JSContext* aCx)
michael@0: {
michael@0:   return BatteryManagerBinding::Wrap(aCx, this);
michael@0: }
michael@0: 
michael@0: double
michael@0: BatteryManager::DischargingTime() const
michael@0: {
michael@0:   if (mCharging || mRemainingTime == kUnknownRemainingTime) {
michael@0:     return std::numeric_limits<double>::infinity();
michael@0:   }
michael@0: 
michael@0:   return mRemainingTime;
michael@0: }
michael@0: 
michael@0: double
michael@0: BatteryManager::ChargingTime() const
michael@0: {
michael@0:   if (!mCharging || mRemainingTime == kUnknownRemainingTime) {
michael@0:     return std::numeric_limits<double>::infinity();
michael@0:   }
michael@0: 
michael@0:   return mRemainingTime;
michael@0: }
michael@0: 
michael@0: void
michael@0: BatteryManager::UpdateFromBatteryInfo(const hal::BatteryInformation& aBatteryInfo)
michael@0: {
michael@0:   mLevel = aBatteryInfo.level();
michael@0:   mCharging = aBatteryInfo.charging();
michael@0:   mRemainingTime = aBatteryInfo.remainingTime();
michael@0: 
michael@0:   // Add some guards to make sure the values are coherent.
michael@0:   if (mLevel == 1.0 && mCharging == true &&
michael@0:       mRemainingTime != kDefaultRemainingTime) {
michael@0:     mRemainingTime = kDefaultRemainingTime;
michael@0:     NS_ERROR("Battery API: When charging and level at 1.0, remaining time "
michael@0:              "should be 0. Please fix your backend!");
michael@0:   }
michael@0: }
michael@0: 
michael@0: void
michael@0: BatteryManager::Notify(const hal::BatteryInformation& aBatteryInfo)
michael@0: {
michael@0:   double previousLevel = mLevel;
michael@0:   bool previousCharging = mCharging;
michael@0:   double previousRemainingTime = mRemainingTime;
michael@0: 
michael@0:   UpdateFromBatteryInfo(aBatteryInfo);
michael@0: 
michael@0:   if (previousCharging != mCharging) {
michael@0:     DispatchTrustedEvent(CHARGINGCHANGE_EVENT_NAME);
michael@0:   }
michael@0: 
michael@0:   if (previousLevel != mLevel) {
michael@0:     DispatchTrustedEvent(LEVELCHANGE_EVENT_NAME);
michael@0:   }
michael@0: 
michael@0:   /*
michael@0:    * There are a few situations that could happen here:
michael@0:    * 1. Charging state changed:
michael@0:    *   a. Previous remaining time wasn't unkwonw, we have to fire an event for
michael@0:    *      the change.
michael@0:    *   b. New remaining time isn't unkwonw, we have to fire an event for it.
michael@0:    * 2. Charging state didn't change but remainingTime did, we have to fire
michael@0:    *    the event that correspond to the current charging state.
michael@0:    */
michael@0:   if (mCharging != previousCharging) {
michael@0:     if (previousRemainingTime != kUnknownRemainingTime) {
michael@0:       DispatchTrustedEvent(previousCharging ? CHARGINGTIMECHANGE_EVENT_NAME
michael@0:                                             : DISCHARGINGTIMECHANGE_EVENT_NAME);
michael@0:     }
michael@0:     if (mRemainingTime != kUnknownRemainingTime) {
michael@0:       DispatchTrustedEvent(mCharging ? CHARGINGTIMECHANGE_EVENT_NAME
michael@0:                                      : DISCHARGINGTIMECHANGE_EVENT_NAME);
michael@0:     }
michael@0:   } else if (previousRemainingTime != mRemainingTime) {
michael@0:     DispatchTrustedEvent(mCharging ? CHARGINGTIMECHANGE_EVENT_NAME
michael@0:                                    : DISCHARGINGTIMECHANGE_EVENT_NAME);
michael@0:   }
michael@0: }
michael@0: 
michael@0: /* static */ bool
michael@0: BatteryManager::HasSupport()
michael@0: {
michael@0:   return Preferences::GetBool("dom.battery.enabled", true);
michael@0: }
michael@0: 
michael@0: } // namespace battery
michael@0: } // namespace dom
michael@0: } // namespace mozilla