/*
    SDL - Simple DirectMedia Layer
    Copyright (C) 1997-2011 Sam Lantinga

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
    License as published by the Free Software Foundation; either
    version 2.1 of the License, or (at your option) any later version.

    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public
    License along with this library; if not, write to the Free Software
    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

    Sam Lantinga
    slouken@libsdl.org
*/
#include "SDL_config.h"

#if SDL_VIDEO_DRIVER_X11

#include <unistd.h> /* For getpid() and readlink() */

#include "SDL_video.h"
#include "SDL_mouse.h"
#include "../SDL_sysvideo.h"
#include "../SDL_pixels_c.h"

#include "SDL_x11video.h"
#include "SDL_x11framebuffer.h"
#include "SDL_x11shape.h"
#include "SDL_x11touch.h" 

#if SDL_VIDEO_DRIVER_PANDORA
#include "SDL_x11opengles.h"
#endif

/* Initialization/Query functions */
static int X11_VideoInit(_THIS);
static void X11_VideoQuit(_THIS);

/* Find out what class name we should use */
static char *
get_classname()
{
    char *spot;
#if defined(__LINUX__) || defined(__FREEBSD__)
    char procfile[1024];
    char linkfile[1024];
    int linksize;
#endif

    /* First allow environment variable override */
    spot = SDL_getenv("SDL_VIDEO_X11_WMCLASS");
    if (spot) {
        return SDL_strdup(spot);
    }

    /* Next look at the application's executable name */
#if defined(__LINUX__) || defined(__FREEBSD__)
#if defined(__LINUX__)
    SDL_snprintf(procfile, SDL_arraysize(procfile), "/proc/%d/exe", getpid());
#elif defined(__FREEBSD__)
    SDL_snprintf(procfile, SDL_arraysize(procfile), "/proc/%d/file",
                 getpid());
#else
#error Where can we find the executable name?
#endif
    linksize = readlink(procfile, linkfile, sizeof(linkfile) - 1);
    if (linksize > 0) {
        linkfile[linksize] = '\0';
        spot = SDL_strrchr(linkfile, '/');
        if (spot) {
            return SDL_strdup(spot + 1);
        } else {
            return SDL_strdup(linkfile);
        }
    }
#endif /* __LINUX__ || __FREEBSD__ */

    /* Finally use the default we've used forever */
    return SDL_strdup("SDL_App");
}

/* X11 driver bootstrap functions */

static int
X11_Available(void)
{
    Display *display = NULL;
    if (SDL_X11_LoadSymbols()) {
        display = XOpenDisplay(NULL);
        if (display != NULL) {
            XCloseDisplay(display);
        }
        SDL_X11_UnloadSymbols();
    }
    return (display != NULL);
}

static void
X11_DeleteDevice(SDL_VideoDevice * device)
{
    SDL_VideoData *data = (SDL_VideoData *) device->driverdata;
    if (data->display) {
        XCloseDisplay(data->display);
    }
    SDL_free(data->windowlist);
    SDL_free(device->driverdata);
#if SDL_VIDEO_DRIVER_PANDORA
    SDL_free(device->gles_data);
#endif
    SDL_free(device);

    SDL_X11_UnloadSymbols();
}

static SDL_VideoDevice *
X11_CreateDevice(int devindex)
{
    SDL_VideoDevice *device;
    SDL_VideoData *data;
    const char *display = NULL; /* Use the DISPLAY environment variable */

    if (!SDL_X11_LoadSymbols()) {
        return NULL;
    }

    /* Initialize all variables that we clean on shutdown */
    device = (SDL_VideoDevice *) SDL_calloc(1, sizeof(SDL_VideoDevice));
    if (!device) {
        SDL_OutOfMemory();
        return NULL;
    }
    data = (struct SDL_VideoData *) SDL_calloc(1, sizeof(SDL_VideoData));
    if (!data) {
        SDL_OutOfMemory();
        SDL_free(device);
        return NULL;
    }
    device->driverdata = data;

#if SDL_VIDEO_DRIVER_PANDORA
    device->gles_data = (struct SDL_PrivateGLESData *) SDL_calloc(1, sizeof(SDL_PrivateGLESData));
    if (!device->gles_data) {
        SDL_OutOfMemory();
        return NULL;
    }
#endif

    /* FIXME: Do we need this?
       if ( (SDL_strncmp(XDisplayName(display), ":", 1) == 0) ||
       (SDL_strncmp(XDisplayName(display), "unix:", 5) == 0) ) {
       local_X11 = 1;
       } else {
       local_X11 = 0;
       }
     */
    data->display = XOpenDisplay(display);
#if defined(__osf__) && defined(SDL_VIDEO_DRIVER_X11_DYNAMIC)
    /* On Tru64 if linking without -lX11, it fails and you get following message.
     * Xlib: connection to ":0.0" refused by server
     * Xlib: XDM authorization key matches an existing client!
     *
     * It succeeds if retrying 1 second later
     * or if running xhost +localhost on shell.
     */
    if (data->display == NULL) {
        SDL_Delay(1000);
        data->display = XOpenDisplay(display);
    }
#endif
    if (data->display == NULL) {
        SDL_free(device);
        SDL_SetError("Couldn't open X11 display");
        return NULL;
    }
#ifdef X11_DEBUG
    XSynchronize(data->display, True);
#endif

    /* Set the function pointers */
    device->VideoInit = X11_VideoInit;
    device->VideoQuit = X11_VideoQuit;
    device->GetDisplayModes = X11_GetDisplayModes;
    device->SetDisplayMode = X11_SetDisplayMode;
    device->SuspendScreenSaver = X11_SuspendScreenSaver;
    device->PumpEvents = X11_PumpEvents;

    device->CreateWindow = X11_CreateWindow;
    device->CreateWindowFrom = X11_CreateWindowFrom;
    device->SetWindowTitle = X11_SetWindowTitle;
    device->SetWindowIcon = X11_SetWindowIcon;
    device->SetWindowPosition = X11_SetWindowPosition;
    device->SetWindowSize = X11_SetWindowSize;
    device->ShowWindow = X11_ShowWindow;
    device->HideWindow = X11_HideWindow;
    device->RaiseWindow = X11_RaiseWindow;
    device->MaximizeWindow = X11_MaximizeWindow;
    device->MinimizeWindow = X11_MinimizeWindow;
    device->RestoreWindow = X11_RestoreWindow;
    device->SetWindowFullscreen = X11_SetWindowFullscreen;
    device->SetWindowGammaRamp = X11_SetWindowGammaRamp;
    device->SetWindowGrab = X11_SetWindowGrab;
    device->DestroyWindow = X11_DestroyWindow;
    device->CreateWindowFramebuffer = X11_CreateWindowFramebuffer;
    device->UpdateWindowFramebuffer = X11_UpdateWindowFramebuffer;
    device->DestroyWindowFramebuffer = X11_DestroyWindowFramebuffer;
    device->GetWindowWMInfo = X11_GetWindowWMInfo;

    device->shape_driver.CreateShaper = X11_CreateShaper;
    device->shape_driver.SetWindowShape = X11_SetWindowShape;
    device->shape_driver.ResizeWindowShape = X11_ResizeWindowShape;

#if SDL_VIDEO_OPENGL_GLX
    device->GL_LoadLibrary = X11_GL_LoadLibrary;
    device->GL_GetProcAddress = X11_GL_GetProcAddress;
    device->GL_UnloadLibrary = X11_GL_UnloadLibrary;
    device->GL_CreateContext = X11_GL_CreateContext;
    device->GL_MakeCurrent = X11_GL_MakeCurrent;
    device->GL_SetSwapInterval = X11_GL_SetSwapInterval;
    device->GL_GetSwapInterval = X11_GL_GetSwapInterval;
    device->GL_SwapWindow = X11_GL_SwapWindow;
    device->GL_DeleteContext = X11_GL_DeleteContext;
#endif
#if SDL_VIDEO_DRIVER_PANDORA
    device->GL_LoadLibrary = X11_GLES_LoadLibrary;
    device->GL_GetProcAddress = X11_GLES_GetProcAddress;
    device->GL_UnloadLibrary = X11_GLES_UnloadLibrary;
    device->GL_CreateContext = X11_GLES_CreateContext;
    device->GL_MakeCurrent = X11_GLES_MakeCurrent;
    device->GL_SetSwapInterval = X11_GLES_SetSwapInterval;
    device->GL_GetSwapInterval = X11_GLES_GetSwapInterval;
    device->GL_SwapWindow = X11_GLES_SwapWindow;
    device->GL_DeleteContext = X11_GLES_DeleteContext;
#endif

    device->SetClipboardText = X11_SetClipboardText;
    device->GetClipboardText = X11_GetClipboardText;
    device->HasClipboardText = X11_HasClipboardText;

    device->free = X11_DeleteDevice;

    return device;
}

VideoBootStrap X11_bootstrap = {
    "x11", "SDL X11 video driver",
    X11_Available, X11_CreateDevice
};

static int (*handler) (Display *, XErrorEvent *) = NULL;
static int
X11_CheckWindowManagerErrorHandler(Display * d, XErrorEvent * e)
{
    if (e->error_code == BadWindow) {
        return (0);
    } else {
        return (handler(d, e));
    }
}

static void
X11_CheckWindowManager(_THIS)
{
    SDL_VideoData *data = (SDL_VideoData *) _this->driverdata;
    Display *display = data->display;
    Atom _NET_SUPPORTING_WM_CHECK;
    int status, real_format;
    Atom real_type;
    unsigned long items_read, items_left;
    unsigned char *propdata;
    Window wm_window = 0;
#ifdef DEBUG_WINDOW_MANAGER
    char *wm_name;
#endif

    /* Set up a handler to gracefully catch errors */
    XSync(display, False);
    handler = XSetErrorHandler(X11_CheckWindowManagerErrorHandler);

    _NET_SUPPORTING_WM_CHECK = XInternAtom(display, "_NET_SUPPORTING_WM_CHECK", False);
    status = XGetWindowProperty(display, DefaultRootWindow(display), _NET_SUPPORTING_WM_CHECK, 0L, 1L, False, XA_WINDOW, &real_type, &real_format, &items_read, &items_left, &propdata);
    if (status == Success && items_read) {
        wm_window = ((Window*)propdata)[0];
    }
    if (propdata) {
        XFree(propdata);
    }

    if (wm_window) {
        status = XGetWindowProperty(display, wm_window, _NET_SUPPORTING_WM_CHECK, 0L, 1L, False, XA_WINDOW, &real_type, &real_format, &items_read, &items_left, &propdata);
        if (status != Success || !items_read || wm_window != ((Window*)propdata)[0]) {
            wm_window = None;
        }
        if (propdata) {
            XFree(propdata);
        }
    }

    /* Reset the error handler, we're done checking */
    XSync(display, False);
    XSetErrorHandler(handler);

    if (!wm_window) {
#ifdef DEBUG_WINDOW_MANAGER
        printf("Couldn't get _NET_SUPPORTING_WM_CHECK property\n");
#endif
        return;
    }
    data->net_wm = SDL_TRUE;

#ifdef DEBUG_WINDOW_MANAGER
    wm_name = X11_GetWindowTitle(_this, wm_window);
    printf("Window manager: %s\n", wm_name);
    SDL_free(wm_name);
#endif
}

int
X11_VideoInit(_THIS)
{
    SDL_VideoData *data = (SDL_VideoData *) _this->driverdata;

    /* Get the window class name, usually the name of the application */
    data->classname = get_classname();

    /* Open a connection to the X input manager */
#ifdef X_HAVE_UTF8_STRING
    if (SDL_X11_HAVE_UTF8) {
        data->im =
            XOpenIM(data->display, NULL, data->classname, data->classname);
    }
#endif

    /* Look up some useful Atoms */
#define GET_ATOM(X) data->X = XInternAtom(data->display, #X, False)
    GET_ATOM(WM_DELETE_WINDOW);
    GET_ATOM(_NET_WM_STATE);
    GET_ATOM(_NET_WM_STATE_HIDDEN);
    GET_ATOM(_NET_WM_STATE_MAXIMIZED_VERT);
    GET_ATOM(_NET_WM_STATE_MAXIMIZED_HORZ);
    GET_ATOM(_NET_WM_STATE_FULLSCREEN);
    GET_ATOM(_NET_WM_NAME);
    GET_ATOM(_NET_WM_ICON_NAME);
    GET_ATOM(_NET_WM_ICON);
    GET_ATOM(UTF8_STRING);

    /* Detect the window manager */
    X11_CheckWindowManager(_this);

    if (X11_InitModes(_this) < 0) {
        return -1;
    }

    if (X11_InitKeyboard(_this) != 0) {
        return -1;
    }
    X11_InitMouse(_this);

    X11_InitTouch(_this);
    return 0;
}

void
X11_VideoQuit(_THIS)
{
    SDL_VideoData *data = (SDL_VideoData *) _this->driverdata;

    if (data->classname) {
        SDL_free(data->classname);
    }
#ifdef X_HAVE_UTF8_STRING
    if (data->im) {
        XCloseIM(data->im);
    }
#endif

    X11_QuitModes(_this);
    X11_QuitKeyboard(_this);
    X11_QuitMouse(_this);
    X11_QuitTouch(_this);
}

SDL_bool
X11_UseDirectColorVisuals(void)
{
    return SDL_getenv("SDL_VIDEO_X11_NODIRECTCOLOR") ? SDL_FALSE : SDL_TRUE;
}

#endif /* SDL_VIDEO_DRIVER_X11 */

/* vim: set ts=4 sw=4 expandtab: */
