/****************************************************************************
 * arch/sim/src/up_x11framebuffer.c
 *
 *   Copyright (C) 2008 Gregory Nutt. All rights reserved.
 *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 * 3. Neither the name NuttX nor the names of its contributors may be
 *    used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *
 ****************************************************************************/

/****************************************************************************
 * Included Files
 ****************************************************************************/

#define CONFIG_SIM_X11NOSHM 1

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <X11/Xlib.h>
#include <X11/Xutil.h>
#include <sys/ipc.h>

#ifndef CONFIG_SIM_X11NOSHM
#  include <sys/shm.h>
#  include <X11/extensions/XShm.h>
#endif

/****************************************************************************
 * Definitions
 ****************************************************************************/

/****************************************************************************
 * Private Type Declarations
 ***************************************************************************/

/****************************************************************************
 * Private Function Prototypes
 ****************************************************************************/

/****************************************************************************
 * Global Variables
 ****************************************************************************/

/****************************************************************************
 * Private Variables
 ****************************************************************************/

static Display *g_display;
static int g_screen;
static Window g_window;
static GC g_gc;
#ifndef CONFIG_SIM_X11NOSHM
static XShmSegmentInfo g_xshminfo;
static int g_xerror;
#endif
static XImage *g_image;
static unsigned char *g_framebuffer;
static unsigned short g_fbpixelwidth;
static unsigned short g_fbpixelheight;
static int g_shmcheckpoint = 0;
static int b_useshm;

/****************************************************************************
 * Name: up_x11createframe
 ***************************************************************************/

static inline int up_x11createframe(void)
{
  XGCValues gcval;
  char *argv[2] = { "nuttx", NULL };
  char *winName = "NuttX";
  char *iconName = "NX";
  XTextProperty winprop;
  XTextProperty iconprop;
  XSizeHints hints;

  g_display = XOpenDisplay(NULL);
  if (g_display == NULL)
    {
      printf("Unable to open display.\n");
      return -1;
    }

  g_screen = DefaultScreen(g_display);
  g_window = XCreateSimpleWindow(g_display, DefaultRootWindow(g_display),
                               0, 0, g_fbpixelwidth, g_fbpixelheight, 2,
                               BlackPixel(g_display, g_screen),
                               BlackPixel(g_display, g_screen));

  XStringListToTextProperty(&winName, 1, &winprop);
  XStringListToTextProperty(&iconName, 1, &iconprop);

  hints.flags = PSize | PMinSize | PMaxSize;
  hints.width = hints.min_width  = hints.max_width  = g_fbpixelwidth;
  hints.height= hints.min_height = hints.max_height = g_fbpixelheight;

  XSetWMProperties(g_display, g_window, &winprop, &iconprop, argv, 1,
                   &hints, NULL, NULL);

  XMapWindow(g_display, g_window);
  XSelectInput(g_display, g_window,
               ButtonPressMask | ButtonReleaseMask |
               ButtonMotionMask | KeyPressMask | ExposureMask);
  gcval.graphics_exposures = 0;
  g_gc = XCreateGC(g_display, g_window, GCGraphicsExposures, &gcval);
  return 0;
}

/****************************************************************************
 * Name: up_x11errorhandler
 ***************************************************************************/

#ifndef CONFIG_SIM_X11NOSHM
static int up_x11errorhandler(Display *display, XErrorEvent *event)
{
  g_xerror = 1;
  return 0;
}
#endif

/****************************************************************************
 * Name: up_x11traperrors
 ***************************************************************************/

#ifndef CONFIG_SIM_X11NOSHM
static void up_x11traperrors(void)
{
  g_xerror = 0;
  XSetErrorHandler(up_x11errorhandler);
}
#endif

/****************************************************************************
 * Name: up_x11untraperrors
 ***************************************************************************/

#ifndef CONFIG_SIM_X11NOSHM
static int up_x11untraperrors(void)
{
  XSync(g_display,0);
  XSetErrorHandler(NULL);
  return g_xerror;
}
#endif

/****************************************************************************
 * Name: up_x11uninitX
 ***************************************************************************/

static void up_x11uninitX(void)
{
  fprintf(stderr, "Uninitalizing X\n");
#ifndef CONFIG_SIM_X11NOSHM
  if (g_shmcheckpoint > 4)
    {
      XShmDetach(g_display, &g_xshminfo);
    }

  if (g_shmcheckpoint > 3)
    {
      shmdt(g_xshminfo.shmaddr);
    }

  if (g_shmcheckpoint > 2)
    {
      shmctl(g_xshminfo.shmid, IPC_RMID, 0);
    }
#endif

  if (g_shmcheckpoint > 1)
    {
      XDestroyImage(g_image);
    }
  XCloseDisplay(g_display);
}

/****************************************************************************
 * Name: up_x11uninitialize
 ***************************************************************************/

#ifndef CONFIG_SIM_X11NOSHM
static void up_x11uninitialize(void)
{
  fprintf(stderr, "Uninitalizing\n");
  if (g_shmcheckpoint > 1)
    {
      if (!b_useshm && g_framebuffer)
        {
          free(g_framebuffer);
          g_framebuffer = 0;
        }
    }

  if (g_shmcheckpoint > 0)
    {
      g_shmcheckpoint = 1;
    }
}
#endif

/****************************************************************************
 * Name: up_x11mapsharedmem
 ***************************************************************************/

static inline int up_x11mapsharedmem(int depth, unsigned int fblen)
{
#ifndef CONFIG_SIM_X11NOSHM
  Status result;
#endif

  atexit(up_x11uninitX);
  g_shmcheckpoint = 1;
  b_useshm = 0;

#ifndef CONFIG_SIM_X11NOSHM
  if (XShmQueryExtension(g_display))
    {
      b_useshm = 1;
      printf("Using shared memory.\n");

      up_x11traperrors();
      g_image = XShmCreateImage(g_display, DefaultVisual(g_display, g_screen), 
                                depth, ZPixmap, NULL, &g_xshminfo,
                                g_fbpixelwidth, g_fbpixelheight);
      if (up_x11untraperrors())
        {
          up_x11uninitialize();
          goto shmerror;
        }
      if (!g_image)
        {
          fprintf(stderr,"Unable to create g_image.");
          return -1;
        }
      g_shmcheckpoint++;

      g_xshminfo.shmid = shmget(IPC_PRIVATE,
                              g_image->bytes_per_line * g_image->height,
                              IPC_CREAT | 0777);
      if (g_xshminfo.shmid < 0)
        {
          up_x11uninitialize();
          goto shmerror;
        }
      g_shmcheckpoint++;

      g_image->data = (char *) shmat(g_xshminfo.shmid, 0, 0);
      if (g_image->data == ((char *) -1))
        {
          up_x11uninitialize();
          goto shmerror;
        }
      g_shmcheckpoint++;

      g_xshminfo.shmaddr = g_image->data;
      g_xshminfo.readOnly = 0;

      up_x11traperrors();
      result = XShmAttach(g_display, &g_xshminfo);
      if (up_x11untraperrors() || !result)
        {
          up_x11uninitialize();
          goto shmerror;
        }

      g_shmcheckpoint++;

    }
  else
#endif
  if (!b_useshm)
    {
#ifndef CONFIG_SIM_X11NOSHM
shmerror:
#endif
      b_useshm = 0;

      g_framebuffer = (unsigned char*)malloc(fblen);

      g_image = XCreateImage(g_display, DefaultVisual(g_display,g_screen), depth,
                             ZPixmap, 0, (char*)g_framebuffer, g_fbpixelwidth, g_fbpixelheight,
                             8, 0);

      if (g_image == NULL)
         {
            fprintf(stderr, "Unable to create g_image\n");
            return -1;
         }

      g_shmcheckpoint++;
    }
  return 0;
}

/****************************************************************************
 * Public Functions
 ***************************************************************************/

/****************************************************************************
 * Name: up_x11initialize
 *
 * Description:
 *   Make an X11 window look like a frame buffer.
 *
 ***************************************************************************/

int up_x11initialize(unsigned short width, unsigned short height,
                     void **fbmem, unsigned int *fblen, unsigned char *bpp,
                     unsigned short *stride)
{
  XWindowAttributes windowAttributes;
  int depth;
  int ret;

  /* Save inputs */

  g_fbpixelwidth  = width;
  g_fbpixelheight = height;

  /* Create the X11 window */

  ret = up_x11createframe();
  if (ret < 0)
    {
      return ret;
    }

  /* Determine the supported pixel bpp of the current window */

  XGetWindowAttributes(g_display, DefaultRootWindow(g_display), &windowAttributes);

  /* Get the pixel depth.  If the depth is 24-bits, use 32 because X expects
   * 32-bit aligment anyway.
   */

  depth =  windowAttributes.depth;
  if (depth == 24)
    {
      depth = 32;
    }
  printf("Pixel bpp is %d bits (using %d)\n", windowAttributes.depth, depth);

  *bpp    = depth;
  *stride = (depth * width / 8);
  *fblen  = (*stride * height);

  /* Map the window to shared memory */

  up_x11mapsharedmem(windowAttributes.depth, *fblen);

  *fbmem  = (void*)g_framebuffer;
  return 0;
}

/****************************************************************************
 * Name: up_x11cmap
 ***************************************************************************/

int up_x11cmap(unsigned short first, unsigned short len,
               unsigned char *red, unsigned char *green,
               unsigned char *blue, unsigned char  *transp)
{
  Colormap cMap;
  int ndx;

  printf("Creating Colormap\n");

  /* Convert each color to X11 scaling */

  cMap = DefaultColormap(g_display, g_screen);
  for (ndx = first; ndx < first + len; ndx++)
    {
      XColor color;

     /* Convert to RGB.  In the NuttX cmap, each component
      * ranges from 0-255; for X11 the range is 0-65536 */

     color.red   = (short)(*red++) << 8;
     color.green = (short)(*green++) << 8;
     color.blue  = (short)(*blue++) << 8;
     color.flags = DoRed | DoGreen | DoBlue;

     /* Then allocate a color for this selection */

     if (!XAllocColor(g_display, cMap, &color))
       {
         fprintf(stderr, "Failed to allocate color%d\n", ndx);
         return -1;
       }
    }

  return 0;
}

/****************************************************************************
 * Name: up_x11update
 ***************************************************************************/

void up_x11update(void)
{
#ifndef CONFIG_SIM_X11NOSHM
  if (b_useshm)
    {
      XShmPutImage(g_display, g_window, g_gc, g_image, 0, 0, 0, 0,
                   g_fbpixelwidth, g_fbpixelheight, 0);
    }
  else
#endif
    {
      XPutImage(g_display, g_window, g_gc, g_image, 0, 0, 0, 0,
                g_fbpixelwidth, g_fbpixelheight);
    }
  XSync(g_display, 0);
}

