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 /* -*- 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 "Hal.h"

 #include "HalImpl.h"

 #include "nsITimer.h"

 #include "mozilla/Preferences.h"

 #include "mozilla/dom/battery/Constants.h"

 #include "nsComponentManagerUtils.h"

 #include <windows.h>

 #include "mozilla/WindowsVersion.h"

 using namespace mozilla::dom::battery;

 namespace mozilla {

 namespace hal_impl {

 static nsCOMPtr<nsITimer> sUpdateTimer;

 /* Power Event API is Vista or later */

 static decltype(RegisterPowerSettingNotification)* sRegisterPowerSettingNotification = nullptr;

 static decltype(UnregisterPowerSettingNotification)* sUnregisterPowerSettingNotification = nullptr;

 static HPOWERNOTIFY sPowerHandle = nullptr;

 static HPOWERNOTIFY sCapacityHandle = nullptr;

 static HWND sHWnd = nullptr;

 static void

 UpdateHandler(nsITimer* aTimer, void* aClosure) {

   NS_ASSERTION(!IsVistaOrLater(),

                "We shouldn't call this function for Vista or later version!");

   static hal::BatteryInformation sLastInfo;

   hal::BatteryInformation currentInfo;

   hal_impl::GetCurrentBatteryInformation(&currentInfo);

   if (sLastInfo.level() != currentInfo.level() ||

       sLastInfo.charging() != currentInfo.charging() ||

       sLastInfo.remainingTime() != currentInfo.remainingTime()) {

     hal::NotifyBatteryChange(currentInfo);

     sLastInfo = currentInfo;

   }

 }

 static

 LRESULT CALLBACK

 BatteryWindowProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam) {

   if (msg != WM_POWERBROADCAST || wParam != PBT_POWERSETTINGCHANGE) {

     return DefWindowProc(hwnd, msg, wParam, lParam);

   }

   hal::BatteryInformation currentInfo;

   // Since we need update remainingTime, we cannot use LPARAM.

   hal_impl::GetCurrentBatteryInformation(&currentInfo);

   hal::NotifyBatteryChange(currentInfo);

   return TRUE;

 }

 void

 EnableBatteryNotifications()

 {

   if (IsVistaOrLater()) {

     // RegisterPowerSettingNotification is from Vista or later.

     // Use this API if available.

     HMODULE hUser32 = GetModuleHandleW(L"USER32.DLL");

     if (!sRegisterPowerSettingNotification)

       sRegisterPowerSettingNotification = (decltype(RegisterPowerSettingNotification)*)

         GetProcAddress(hUser32, "RegisterPowerSettingNotification");

     if (!sUnregisterPowerSettingNotification)

       sUnregisterPowerSettingNotification = (decltype(UnregisterPowerSettingNotification)*)

         GetProcAddress(hUser32, "UnregisterPowerSettingNotification");

     if (!sRegisterPowerSettingNotification ||

         !sUnregisterPowerSettingNotification) {

       NS_ASSERTION(false, "Canot find PowerSettingNotification functions.");

       return;

     }

     // Create custom window to watch battery event

     // If we can get Gecko's window handle, this is unnecessary.

     if (sHWnd == nullptr) {

       WNDCLASSW wc;

       HMODULE hSelf = GetModuleHandle(nullptr);

       if (!GetClassInfoW(hSelf, L"MozillaBatteryClass", &wc)) {

         ZeroMemory(&wc, sizeof(WNDCLASSW));

         wc.hInstance = hSelf;

         wc.lpfnWndProc = BatteryWindowProc;

         wc.lpszClassName = L"MozillaBatteryClass";

         RegisterClassW(&wc);

       }

       sHWnd = CreateWindowW(L"MozillaBatteryClass", L"Battery Watcher",

                             0, 0, 0, 0, 0,

                             nullptr, nullptr, hSelf, nullptr);

     }

     if (sHWnd == nullptr) {

       return;

     }

     sPowerHandle =

       sRegisterPowerSettingNotification(sHWnd,

                                         &GUID_ACDC_POWER_SOURCE,

                                         DEVICE_NOTIFY_WINDOW_HANDLE);

     sCapacityHandle =

       sRegisterPowerSettingNotification(sHWnd,

                                         &GUID_BATTERY_PERCENTAGE_REMAINING,

                                         DEVICE_NOTIFY_WINDOW_HANDLE);

   } else

   {

     // for Windows XP.  If we remove Windows XP support,

     // we should remove timer-based power notification

     sUpdateTimer = do_CreateInstance(NS_TIMER_CONTRACTID);

     if (sUpdateTimer) {

       sUpdateTimer->InitWithFuncCallback(UpdateHandler,

                                          nullptr,

                                          Preferences::GetInt("dom.battery.timer",

                                                              30000 /* 30s */),

                                          nsITimer::TYPE_REPEATING_SLACK);

     } 

   }

 }

 void

 DisableBatteryNotifications()

 {

   if (IsVistaOrLater()) {

     if (sPowerHandle) {

       sUnregisterPowerSettingNotification(sPowerHandle);

       sPowerHandle = nullptr;

     }

     if (sCapacityHandle) {

       sUnregisterPowerSettingNotification(sCapacityHandle);

       sCapacityHandle = nullptr;

     }

     if (sHWnd) {

       DestroyWindow(sHWnd);

       sHWnd = nullptr;

     }

   } else

   {

     if (sUpdateTimer) {

       sUpdateTimer->Cancel();

       sUpdateTimer = nullptr;

     }

   }

 }

 void

 GetCurrentBatteryInformation(hal::BatteryInformation* aBatteryInfo)

 {

   SYSTEM_POWER_STATUS status;

   if (!GetSystemPowerStatus(&status)) {

     aBatteryInfo->level() = kDefaultLevel;

     aBatteryInfo->charging() = kDefaultCharging;

     aBatteryInfo->remainingTime() = kDefaultRemainingTime;

     return;

   }

   aBatteryInfo->level() =

     status.BatteryLifePercent == 255 ? kDefaultLevel

                                      : ((double)status.BatteryLifePercent) / 100.0;

   aBatteryInfo->charging() = (status.ACLineStatus != 0);

   if (status.ACLineStatus != 0) {

     if (aBatteryInfo->level() == 1.0) {

       // GetSystemPowerStatus API may returns -1 for BatteryFullLifeTime.

       // So, if battery is 100%, set kDefaultRemainingTime at force.

       aBatteryInfo->remainingTime() = kDefaultRemainingTime;

     } else {

       aBatteryInfo->remainingTime() =

         status.BatteryFullLifeTime == (DWORD)-1 ? kUnknownRemainingTime

                                                 : status.BatteryFullLifeTime;

     }

   } else {

     aBatteryInfo->remainingTime() =

       status.BatteryLifeTime == (DWORD)-1 ? kUnknownRemainingTime

                                           : status.BatteryLifeTime;

   }

 }

 } // hal_impl

 } // mozilla