/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */

/* vim:expandtab:shiftwidth=4:tabstop=4:

 */

/* 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 <gtk/gtk.h>

#include "nsIdleServiceGTK.h"

#include "nsIServiceManager.h"

#include "nsDebug.h"

#include "prlink.h"

#include "mozilla/Logging.h"

using mozilla::LogLevel;

static mozilla::LazyLogModule sIdleLog("nsIIdleService");

typedef bool (*_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 bool sInitialized = false;

static _XScreenSaverQueryExtension_fn _XSSQueryExtension = nullptr;

static _XScreenSaverAllocInfo_fn _XSSAllocInfo = nullptr;

static _XScreenSaverQueryInfo_fn _XSSQueryInfo = nullptr;

static void Initialize() {

  if (!GDK_IS_X11_DISPLAY(gdk_display_get_default())) return;

  // This will leak - See comments in ~nsIdleServiceGTK().

  PRLibrary* xsslib = PR_LoadLibrary("libXss.so.1");

  if (!xsslib)  // ouch.

  {

    MOZ_LOG(sIdleLog, LogLevel::Warning, ("Failed to find libXss.so!\n"));

    return;

  }

  _XSSQueryExtension = (_XScreenSaverQueryExtension_fn)PR_FindFunctionSymbol(

      xsslib, "XScreenSaverQueryExtension");

  _XSSAllocInfo = (_XScreenSaverAllocInfo_fn)PR_FindFunctionSymbol(

      xsslib, "XScreenSaverAllocInfo");

  _XSSQueryInfo = (_XScreenSaverQueryInfo_fn)PR_FindFunctionSymbol(

      xsslib, "XScreenSaverQueryInfo");

  if (!_XSSQueryExtension)

    MOZ_LOG(sIdleLog, LogLevel::Warning,

            ("Failed to get XSSQueryExtension!\n"));

  if (!_XSSAllocInfo)

    MOZ_LOG(sIdleLog, LogLevel::Warning, ("Failed to get XSSAllocInfo!\n"));

  if (!_XSSQueryInfo)

    MOZ_LOG(sIdleLog, LogLevel::Warning, ("Failed to get XSSQueryInfo!\n"));

  sInitialized = true;

}

nsIdleServiceGTK::nsIdleServiceGTK() : mXssInfo(nullptr) { Initialize(); }

nsIdleServiceGTK::~nsIdleServiceGTK() {

  if (mXssInfo) XFree(mXssInfo);

// It is not safe to unload libXScrnSaver until each display is closed because

// the library registers callbacks through XESetCloseDisplay (Bug 397607).

// (Also the library and its functions are scoped for the file not the object.)

#if 0

    if (xsslib) {

        PR_UnloadLibrary(xsslib);

        xsslib = nullptr;

    }

#endif

}

bool nsIdleServiceGTK::PollIdleTime(uint32_t* aIdleTime) {

  if (!sInitialized) {

    // For some reason, we could not find xscreensaver.

    return false;

  }

  // Ask xscreensaver about idle time:

  *aIdleTime = 0;

  // We might not have a display (cf. in xpcshell)

  Display* dplay = GDK_DISPLAY_XDISPLAY(gdk_display_get_default());

  if (!dplay) {

    MOZ_LOG(sIdleLog, LogLevel::Warning, ("No display found!\n"));

    return false;

  }

  if (!_XSSQueryExtension || !_XSSAllocInfo || !_XSSQueryInfo) {

    return false;

  }

  int event_base, error_base;

  if (_XSSQueryExtension(dplay, &event_base, &error_base)) {

    if (!mXssInfo) mXssInfo = _XSSAllocInfo();

    if (!mXssInfo) return false;

    _XSSQueryInfo(dplay, GDK_ROOT_WINDOW(), mXssInfo);

    *aIdleTime = mXssInfo->idle;

    return true;

  }

  // If we get here, we couldn't get to XScreenSaver:

  MOZ_LOG(sIdleLog, LogLevel::Warning, ("XSSQueryExtension returned false!\n"));

  return false;

}

bool nsIdleServiceGTK::UsePollMode() { return sInitialized; }