gecko-dev/dom/battery/BatteryManager.cpp

148 lines
4.2 KiB
C++

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