Bug 343416 - implement nsIIdleService - API to get the last time user activity occurred on the system

r=roc@ocallahan.org (Robert O'Callahan)
sr=neil@parkwaycc.co.uk (Neil Rashbrook)

widget/public/Makefile.in

@@ -114,6 +114,7 @@ XPIDLSRCS	= \
 		nsIPrintSettings.idl \
 		nsIPrintSettingsService.idl \
 		nsIPrintOptions.idl \
+		nsIIdleService.idl \
 		$(NULL)
 
 ifeq ($(MOZ_WIDGET_TOOLKIT),windows)

widget/public/nsIIdleService.idl

@@ -0,0 +1,97 @@
+/* -*- Mode: IDL; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ *
+ * ***** BEGIN LICENSE BLOCK *****
+ * Version: MPL 1.1/GPL 2.0/LGPL 2.1
+ *
+ * The contents of this file are subject to the Mozilla Public License Version
+ * 1.1 (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ * http://www.mozilla.org/MPL/
+ *
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+ * for the specific language governing rights and limitations under the
+ * License.
+ *
+ * The Original Code is mozilla.org code.
+ *
+ * The Initial Developer of the Original Code is
+ * Gijs Kruitbosch <gijskruitbosch@gmail.com>
+ * Portions created by the Initial Developer are Copyright (C) 2007
+ * the Initial Developer. All Rights Reserved.
+ *
+ * Contributor(s):
+ *   Gijs Kruitbosch <gijskruitbosch@gmail.com>
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * either the GNU General Public License Version 2 or later (the "GPL"), or
+ * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
+ * in which case the provisions of the GPL or the LGPL are applicable instead
+ * of those above. If you wish to allow use of your version of this file only
+ * under the terms of either the GPL or the LGPL, and not to allow others to
+ * use your version of this file under the terms of the MPL, indicate your
+ * decision by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL or the LGPL. If you do not delete
+ * the provisions above, a recipient may use your version of this file under
+ * the terms of any one of the MPL, the GPL or the LGPL.
+ *
+ * ***** END LICENSE BLOCK ***** */
+
+#include "nsISupports.idl"
+interface nsIObserver;
+
+/**
+ * This interface lets you monitor how long the user has been 'idle',
+ * i.e. not used their mouse or keyboard. You can get the idle time directly,
+ * but in most cases you will want to register an observer for a predefined
+ * interval. The observer will get an 'idle' notification when the user is idle
+ * for that interval (or longer), and receive a 'back' notification when the
+ * user starts using their computer again.
+ */
+
+[scriptable, uuid(cc52f19a-63ae-4a1c-9cc3-e79eace0b471)]
+interface nsIIdleService : nsISupports
+{
+    /**
+     * The amount of time in milliseconds that has passed
+     * since the last user activity.
+     */
+    readonly attribute unsigned long idleTime;
+
+    /**
+     * Add an observer to be notified when the user idles for some period of
+     * time, and when they get back from that.
+     *
+     * @param observer the observer to be notified
+     * @param time the amount of time in minutes the user should idle before
+     *             the observer should be notified.
+     *
+     * @note
+     * The subject of the notification the observer will get is always the
+     * nsIIdleService itself.
+     * When the user goes idle, the observer topic is "idle" and when they get
+     * back, the observer topic is "back".
+     * The data param for the notification contains the current user idle time.
+     *
+     * @note
+     * You can add the same observer twice.
+     * @note
+     * Most implementations need to poll the OS for idle info themselves,
+     * meaning your notifications could arrive with a delay up to the length
+     * of the polling interval in that implementation.
+     * Current implementations use a delay of 5 seconds.
+     */
+    void addIdleObserver(in nsIObserver observer, in unsigned long time);
+
+    /**
+     * Remove an observer registered with addIdleObserver.
+     * @param observer the observer that needs to be removed.
+     * @param time the amount of time they were listening for.
+     * @note
+     * Removing an observer will remove it once, for the idle time you specify. 
+     * If you have added an observer multiple times, you will need to remove it
+     * just as many times.
+     */
+    void removeIdleObserver(in nsIObserver observer, in unsigned long time);
+};
+

widget/public/nsWidgetsCID.h

@@ -144,6 +144,9 @@
 #define NS_SCREENMANAGER_CID \
 { 0xc401eb80, 0xf9ea, 0x11d3, { 0xbb, 0x6f, 0xe7, 0x32, 0xb7, 0x3e, 0xbe, 0x7c } }
 
+// {6987230e-0089-4e78-bc5f-1493ee7519fa}
+#define NS_IDLE_SERVICE_CID \
+{ 0x6987230e, 0x0098, 0x4e78, { 0xbc, 0x5f, 0x14, 0x93, 0xee, 0x75, 0x19, 0xfa } }
 
 //-----------------------------------------------------------
 //Printing

widget/src/gtk2/Makefile.in

@@ -113,6 +113,7 @@ CPPSRCS		= \
 		nsPrintJobFactoryGTK.cpp \
 		nsPrintJobGTK.cpp \
 		nsTempfilePS.cpp \
+		nsIdleServiceGTK.cpp \
 		$(NULL)
 
 # build our subdirs, too

widget/src/gtk2/nsIdleServiceGTK.cpp

@@ -0,0 +1,146 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* vim:expandtab:shiftwidth=4:tabstop=4:
+ */
+/* ***** BEGIN LICENSE BLOCK *****
+ * Version: MPL 1.1/GPL 2.0/LGPL 2.1
+ *
+ * The contents of this file are subject to the Mozilla Public License Version
+ * 1.1 (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ * http://www.mozilla.org/MPL/
+ *
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+ * for the specific language governing rights and limitations under the
+ * License.
+ *
+ * The Original Code is mozilla.org code.
+ *
+ * The Initial Developer of the Original Code is
+ * Gijs Kruitbosch <gijskruitbosch@gmail.com>.
+ * Portions created by the Initial Developer are Copyright (C) 2007
+ * the Initial Developer. All Rights Reserved.
+ *
+ * Contributor(s):
+ *  Gijs Kruitbosch <gijskruitbosch@gmail.com> 
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * either the GNU General Public License Version 2 or later (the "GPL"), or
+ * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
+ * in which case the provisions of the GPL or the LGPL are applicable instead
+ * of those above. If you wish to allow use of your version of this file only
+ * under the terms of either the GPL or the LGPL, and not to allow others to
+ * use your version of this file under the terms of the MPL, indicate your
+ * decision by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL or the LGPL. If you do not delete
+ * the provisions above, a recipient may use your version of this file under
+ * the terms of any one of the MPL, the GPL or the LGPL.
+ *
+ * ***** END LICENSE BLOCK ***** */
+
+#include "nsIdleServiceGTK.h"
+#include "nsIServiceManager.h"
+#include "nsDebug.h"
+#include "prlink.h"
+#include "prlog.h"
+
+
+#ifdef PR_LOGGING
+static PRLogModuleInfo* sIdleLog = nsnull;
+#endif
+
+typedef PRBool (*_XScreenSaverQueryExtension_fn)(Display* dpy, int* event_base,
+                                                 int* error_base);
+
+typedef XScreenSaverInfo* (*_XScreenSaverAllocInfo_fn)(void);
+
+typedef void (*_XScreenSaverQueryInfo_fn)(Display* dpy, Drawable drw,
+                                          XScreenSaverInfo *info);
+
+static PRLibrary* xsslib = nsnull;
+static _XScreenSaverQueryExtension_fn _XSSQueryExtension = nsnull;
+static _XScreenSaverAllocInfo_fn _XSSAllocInfo = nsnull;
+static _XScreenSaverQueryInfo_fn _XSSQueryInfo = nsnull;
+
+
+NS_IMPL_ISUPPORTS1(nsIdleServiceGTK, nsIIdleService)
+
+nsIdleServiceGTK::nsIdleServiceGTK()
+    : mXssInfo(nsnull)
+{
+#ifdef PR_LOGGING
+    if (!sIdleLog)
+        sIdleLog = PR_NewLogModule("nsIIdleService");
+#endif
+
+    xsslib = PR_LoadLibrary("libXss.so.1");
+    if (!xsslib) // ouch.
+    {
+#ifdef PR_LOGGING
+        PR_LOG(sIdleLog, PR_LOG_WARNING, ("Failed to find libXss.so!\n"));
+#endif
+        return;
+    }
+
+    _XSSQueryExtension = (_XScreenSaverQueryExtension_fn)
+        PR_FindFunctionSymbol(xsslib, "XScreenSaverQueryExtension");
+    _XSSAllocInfo = (_XScreenSaverAllocInfo_fn)
+        PR_FindFunctionSymbol(xsslib, "XScreenSaverAllocInfo");
+    _XSSQueryInfo = (_XScreenSaverQueryInfo_fn)
+        PR_FindFunctionSymbol(xsslib, "XScreenSaverQueryInfo");
+#ifdef PR_LOGGING
+    if (!_XSSQueryExtension)
+        PR_LOG(sIdleLog, PR_LOG_WARNING, ("Failed to get XSSQueryExtension!\n"));
+    if (!_XSSAllocInfo)
+        PR_LOG(sIdleLog, PR_LOG_WARNING, ("Failed to get XSSAllocInfo!\n"));
+    if (!_XSSQueryInfo)
+        PR_LOG(sIdleLog, PR_LOG_WARNING, ("Failed to get XSSQueryInfo!\n"));
+#endif
+ 
+}
+
+nsIdleServiceGTK::~nsIdleServiceGTK()
+{
+    if (mXssInfo)
+        XFree(mXssInfo);
+    if (xsslib)
+        PR_UnloadLibrary(xsslib);
+}
+
+NS_IMETHODIMP
+nsIdleServiceGTK::GetIdleTime(PRUint32 *aTimeDiff)
+{
+    // Ask xscreensaver about idle time:
+    int event_base, error_base;
+    *aTimeDiff = 0;
+
+    // We might not have a display (cf. in xpcshell)
+    Display *dplay = GDK_DISPLAY();
+    if (!dplay || !_XSSQueryExtension || !_XSSAllocInfo || !_XSSQueryInfo)
+    {
+#ifdef PR_LOGGING
+        if (!dplay)
+            PR_LOG(sIdleLog, PR_LOG_WARNING, ("No display found!\n"));
+        else
+            PR_LOG(sIdleLog, PR_LOG_WARNING, ("One of the Xss functions is missing!\n"));
+#endif
+        return NS_ERROR_FAILURE;
+    }
+
+    if (_XSSQueryExtension(dplay, &event_base, &error_base))
+    {
+        if (!mXssInfo)
+            mXssInfo = _XSSAllocInfo();
+        if (!mXssInfo)
+            return NS_ERROR_OUT_OF_MEMORY;
+        _XSSQueryInfo(dplay, GDK_ROOT_WINDOW(), mXssInfo);
+        *aTimeDiff = mXssInfo->idle;
+        return NS_OK;
+    }
+    // If we get here, we couldn't get to XScreenSaver:
+#ifdef PR_LOGGING
+    PR_LOG(sIdleLog, PR_LOG_WARNING, ("XSSQueryExtension returned false!\n"));
+#endif
+    return NS_ERROR_FAILURE;
+}
+

widget/src/gtk2/nsIdleServiceGTK.h

@@ -0,0 +1,70 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* vim:expandtab:shiftwidth=4:tabstop=4:
+ */
+/* ***** BEGIN LICENSE BLOCK *****
+ * Version: MPL 1.1/GPL 2.0/LGPL 2.1
+ *
+ * The contents of this file are subject to the Mozilla Public License Version
+ * 1.1 (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ * http://www.mozilla.org/MPL/
+ *
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+ * for the specific language governing rights and limitations under the
+ * License.
+ *
+ * The Original Code is mozilla.org code.
+ *
+ * The Initial Developer of the Original Code is
+ * Gijs Kruitbosch <gijskruitbosch@gmail.com>.
+ * Portions created by the Initial Developer are Copyright (C) 2007
+ * the Initial Developer. All Rights Reserved.
+ *
+ * Contributor(s):
+ *  Gijs Kruitbosch <gijskruitbosch@gmail.com> 
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * either the GNU General Public License Version 2 or later (the "GPL"), or
+ * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
+ * in which case the provisions of the GPL or the LGPL are applicable instead
+ * of those above. If you wish to allow use of your version of this file only
+ * under the terms of either the GPL or the LGPL, and not to allow others to
+ * use your version of this file under the terms of the MPL, indicate your
+ * decision by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL or the LGPL. If you do not delete
+ * the provisions above, a recipient may use your version of this file under
+ * the terms of any one of the MPL, the GPL or the LGPL.
+ *
+ * ***** END LICENSE BLOCK ***** */
+
+#ifndef nsIdleServiceGTK_h__
+#define nsIdleServiceGTK_h__
+
+#include "nsIdleService.h"
+#include <X11/Xlib.h>
+#include <X11/Xutil.h>
+#include <gdk/gdkx.h>
+
+typedef struct {
+    Window window;              // Screen saver window
+    int state;                  // ScreenSaver(Off,On,Disabled)
+    int kind;                   // ScreenSaver(Blanked,Internal,External)
+    unsigned long til_or_since; // milliseconds since/til screensaver kicks in
+    unsigned long idle;         // milliseconds idle
+    unsigned long event_mask;   // event stuff
+} XScreenSaverInfo;
+
+class nsIdleServiceGTK : public nsIdleService
+{
+public:
+    NS_DECL_ISUPPORTS
+    nsIdleServiceGTK();
+
+    NS_IMETHOD GetIdleTime(PRUint32* idleTime);
+private:
+    ~nsIdleServiceGTK();
+    XScreenSaverInfo* mXssInfo;
+};
+
+#endif // nsIdleServiceGTK_h__

widget/src/gtk2/nsWidgetFactory.cpp

@@ -59,6 +59,7 @@
 #include "nsIPrefService.h"
 #include "nsIPrefBranch.h"
 #include "nsImageToPixbuf.h"
+#include "nsIdleServiceGTK.h"
 
 #ifdef NATIVE_THEME_SUPPORT
 #include "nsNativeThemeGTK.h"
@@ -95,6 +96,7 @@ NS_GENERIC_FACTORY_CONSTRUCTOR_INIT(nsPrintOptionsGTK, Init)
 NS_GENERIC_FACTORY_CONSTRUCTOR(nsPrinterEnumeratorGTK)
 NS_GENERIC_FACTORY_CONSTRUCTOR_INIT(nsPrintSession, Init)
 NS_GENERIC_FACTORY_CONSTRUCTOR(nsImageToPixbuf)
+NS_GENERIC_FACTORY_CONSTRUCTOR(nsIdleServiceGTK)
 
 static NS_IMETHODIMP
 nsFilePickerConstructor(nsISupports *aOuter, REFNSIID aIID,
@@ -268,6 +270,10 @@ static const nsModuleComponentInfo components[] =
     NS_IMAGE_TO_PIXBUF_CID,
     "@mozilla.org/widget/image-to-gdk-pixbuf;1",
     nsImageToPixbufConstructor },
+  { "User Idle Service",
+    NS_IDLE_SERVICE_CID,
+    "@mozilla.org/widget/idleservice;1",
+    nsIdleServiceGTKConstructor },
 };
 
 PR_STATIC_CALLBACK(void)

widget/src/xpwidgets/Makefile.in

@@ -81,6 +81,7 @@ CPPSRCS		= \
 		nsPrintSettingsImpl.cpp \
 		nsPrintSession.cpp \
 		nsWidgetAtoms.cpp \
+		nsIdleService.cpp \
 		$(NULL)
 
 ifneq (,$(filter beos os2 mac qt cocoa windows,$(MOZ_WIDGET_TOOLKIT)))

widget/src/xpwidgets/nsIdleService.cpp

@@ -0,0 +1,178 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* vim:expandtab:shiftwidth=4:tabstop=4:
+ */
+/* ***** BEGIN LICENSE BLOCK *****
+ * Version: MPL 1.1/GPL 2.0/LGPL 2.1
+ *
+ * The contents of this file are subject to the Mozilla Public License Version
+ * 1.1 (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ * http://www.mozilla.org/MPL/
+ *
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+ * for the specific language governing rights and limitations under the
+ * License.
+ *
+ * The Original Code is mozilla.org code.
+ *
+ * The Initial Developer of the Original Code is
+ * Gijs Kruitbosch <gijskruitbosch@gmail.com>.
+ * Portions created by the Initial Developer are Copyright (C) 2007
+ * the Initial Developer. All Rights Reserved.
+ *
+ * Contributor(s):
+ *  Gijs Kruitbosch <gijskruitbosch@gmail.com> 
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * either the GNU General Public License Version 2 or later (the "GPL"), or
+ * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
+ * in which case the provisions of the GPL or the LGPL are applicable instead
+ * of those above. If you wish to allow use of your version of this file only
+ * under the terms of either the GPL or the LGPL, and not to allow others to
+ * use your version of this file under the terms of the MPL, indicate your
+ * decision by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL or the LGPL. If you do not delete
+ * the provisions above, a recipient may use your version of this file under
+ * the terms of any one of the MPL, the GPL or the LGPL.
+ *
+ * ***** END LICENSE BLOCK ***** */
+
+#include "nsIdleService.h"
+#include "nsString.h"
+#include "nsIServiceManager.h"
+#include "nsDebug.h"
+#include "nsCOMArray.h"
+
+// observer topics used:
+#define OBSERVER_TOPIC_IDLE "idle"
+#define OBSERVER_TOPIC_BACK "back"
+// interval in milliseconds between internal idle time requests
+#define IDLE_POLL_INTERVAL 5000
+
+
+
+// Use this to find previously added observers in our array:
+class IdleListenerComparator
+{
+public:
+    PRBool Equals(IdleListener a, IdleListener b) const
+    {
+        return (a.observer == b.observer) &&
+               (a.reqIdleTime == b.reqIdleTime);
+    }
+};
+
+nsIdleService::nsIdleService()
+{
+}
+
+nsIdleService::~nsIdleService()
+{
+    if (mTimer)
+        mTimer->Cancel();
+}
+
+NS_IMETHODIMP
+nsIdleService::AddIdleObserver(nsIObserver* aObserver, PRUint32 aIdleTime)
+{
+    NS_ENSURE_ARG_POINTER(aObserver);
+    NS_ENSURE_ARG(aIdleTime);
+
+    // Put the time + observer in a struct we can keep:
+    IdleListener listener(aObserver, aIdleTime);
+
+    if (!mArrayListeners.AppendElement(listener))
+        return NS_ERROR_OUT_OF_MEMORY;
+
+    // Initialize our timer callback if it's not there already.
+    if (!mTimer)
+    {
+        nsresult rv;
+        mTimer = do_CreateInstance(NS_TIMER_CONTRACTID, &rv);
+        if (NS_FAILED(rv))
+            return rv;
+        mTimer->InitWithFuncCallback(IdleTimerCallback, this, IDLE_POLL_INTERVAL,
+                                     nsITimer::TYPE_REPEATING_SLACK);
+    }
+
+    // Make sure our observer goes into 'idle' immediately if applicable.
+    CheckAwayState();
+
+    return NS_OK;
+}
+
+NS_IMETHODIMP
+nsIdleService::RemoveIdleObserver(nsIObserver* aObserver, PRUint32 aTime)
+{
+    NS_ENSURE_ARG_POINTER(aObserver);
+    NS_ENSURE_ARG(aTime);
+    IdleListener listener(aObserver, aTime);
+
+    // Find the entry and remove it:
+    IdleListenerComparator c;
+    if (mArrayListeners.RemoveElement(listener, c))
+    {
+        if (mTimer && mArrayListeners.IsEmpty())
+        {
+            mTimer->Cancel();
+            mTimer = nsnull;
+        }
+        return NS_OK;
+    }
+
+    // If we get here, we haven't removed anything:
+    return NS_ERROR_FAILURE;
+}
+
+void
+nsIdleService::IdleTimerCallback(nsITimer* aTimer, void* aClosure)
+{
+    NS_STATIC_CAST(nsIdleService*, aClosure)->CheckAwayState();
+}
+
+void
+nsIdleService::CheckAwayState()
+{
+    // Get the idle time.
+    PRUint32 idleTime;
+    if (NS_FAILED(GetIdleTime(&idleTime)))
+        return;
+
+    nsAutoString timeStr;
+    timeStr.AppendInt(idleTime);
+
+    // Change state first, and save observers that need notification, so
+    // removing things will always work without upsetting notifications.
+    nsCOMArray<nsIObserver> idleListeners;
+    nsCOMArray<nsIObserver> hereListeners;
+    for (PRUint32 i = 0; i < mArrayListeners.Length(); i++)
+    {
+        IdleListener& curListener = mArrayListeners.ElementAt(i);
+        if ((curListener.reqIdleTime * 60000 <= idleTime) &&
+            !curListener.isIdle)
+        {
+            curListener.isIdle = PR_TRUE;
+            idleListeners.AppendObject(curListener.observer);
+        }
+        else if ((curListener.reqIdleTime * 60000 > idleTime) &&
+                 curListener.isIdle)
+        {
+            curListener.isIdle = PR_FALSE;
+            hereListeners.AppendObject(curListener.observer);
+        }
+    }
+
+    // Notify listeners gone idle:
+    for (PRInt32 i = 0; i < idleListeners.Count(); i++)
+    {
+        idleListeners[i]->Observe(this, OBSERVER_TOPIC_IDLE, timeStr.get());
+    }
+
+    // Notify listeners that came back:
+    for (PRInt32 i = 0; i < hereListeners.Count(); i++)
+    {
+        hereListeners[i]->Observe(this, OBSERVER_TOPIC_BACK, timeStr.get());
+    }
+}
+

widget/src/xpwidgets/nsIdleService.h

@@ -0,0 +1,84 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* vim:expandtab:shiftwidth=4:tabstop=4:
+ */
+/* ***** BEGIN LICENSE BLOCK *****
+ * Version: MPL 1.1/GPL 2.0/LGPL 2.1
+ *
+ * The contents of this file are subject to the Mozilla Public License Version
+ * 1.1 (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ * http://www.mozilla.org/MPL/
+ *
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+ * for the specific language governing rights and limitations under the
+ * License.
+ *
+ * The Original Code is mozilla.org code.
+ *
+ * The Initial Developer of the Original Code is
+ * Gijs Kruitbosch <gijskruitbosch@gmail.com>.
+ * Portions created by the Initial Developer are Copyright (C) 2007
+ * the Initial Developer. All Rights Reserved.
+ *
+ * Contributor(s):
+ *  Gijs Kruitbosch <gijskruitbosch@gmail.com> 
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * either the GNU General Public License Version 2 or later (the "GPL"), or
+ * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
+ * in which case the provisions of the GPL or the LGPL are applicable instead
+ * of those above. If you wish to allow use of your version of this file only
+ * under the terms of either the GPL or the LGPL, and not to allow others to
+ * use your version of this file under the terms of the MPL, indicate your
+ * decision by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL or the LGPL. If you do not delete
+ * the provisions above, a recipient may use your version of this file under
+ * the terms of any one of the MPL, the GPL or the LGPL.
+ *
+ * ***** END LICENSE BLOCK ***** */
+
+#ifndef nsIdleService_h__
+#define nsIdleService_h__
+
+#include "nsIIdleService.h"
+#include "nsCOMPtr.h"
+#include "nsITimer.h"
+#include "nsTArray.h"
+#include "nsIObserver.h"
+
+// Class we can use to store an observer with its associated idle time
+// requirement and whether or not the observer thinks it's "idle".
+class IdleListener {
+public:
+    nsCOMPtr<nsIObserver> observer;
+    PRUint32 reqIdleTime;
+    PRBool isIdle;
+
+    IdleListener(nsIObserver* obs, PRUint32 reqIT, PRBool aIsIdle = PR_FALSE) :
+        observer(obs), reqIdleTime(reqIT), isIdle(aIsIdle) {}
+    ~IdleListener() {}
+};
+
+class nsIdleService : public nsIIdleService
+{
+public:
+    nsIdleService();
+
+    // Implement nsIIdleService methods, but not the idleTime getter,
+    // which is platform-dependent.
+    NS_IMETHOD AddIdleObserver(nsIObserver* aObserver, PRUint32 aIdleTime);
+    NS_IMETHOD RemoveIdleObserver(nsIObserver* aObserver, PRUint32 aIdleTime);
+
+    static void IdleTimerCallback(nsITimer* aTimer, void* aClosure);
+
+protected:
+    void CheckAwayState();
+    ~nsIdleService();
+
+private:
+    nsCOMPtr<nsITimer> mTimer;
+    nsTArray<IdleListener> mArrayListeners;
+};
+
+#endif // nsIdleService_h__