/* Copyright (c) Mark J. Kilgard, 1994. */

/* This program is freely distributable without licensing fees
   and is provided without guarantee or warrantee expressed or
   implied. This program is -not- in the public domain. */

#include <stdlib.h>
#include <string.h>
#include <stdio.h>

#if !defined(WIN32)
#include <X11/Xlib.h>
#include <X11/Xatom.h>
#endif /* !WIN32 */

/* SGI optimization introduced in IRIX 6.3 to avoid X server
   round trips for interning common X atoms. */
#if defined(_SGI_EXTRA_PREDEFINES) && !defined(NO_FAST_ATOMS)
#include <X11/SGIFastAtom.h>
#else
#define XSGIFastInternAtom(dpy,string,fast_name,how) XInternAtom(dpy,string,how)
#endif

#include <GL/glut.h>
#include "glutint.h"

/* GLUT inter-file variables */
/* *INDENT-OFF* */
char *__glutProgramName = NULL;
int __glutArgc = 0;
char **__glutArgv = NULL;
char *__glutGeometry = NULL;
Display *__glutDisplay = NULL;
int __glutScreen;
Window __glutRoot;
int __glutScreenHeight;
int __glutScreenWidth;
GLboolean __glutIconic = GL_FALSE;
GLboolean __glutDebug = GL_FALSE;
unsigned int __glutDisplayMode =
  GLUT_RGB | GLUT_SINGLE | GLUT_DEPTH;
char *__glutDisplayString = NULL;
int __glutConnectionFD;
XSizeHints __glutSizeHints = {0};
int __glutInitWidth = 300, __glutInitHeight = 300;
int __glutInitX = -1, __glutInitY = -1;
GLboolean __glutForceDirect = GL_FALSE,
  __glutTryDirect = GL_TRUE;
Atom __glutWMDeleteWindow;
#if defined(WIN32)
int __glutMinWindowWidth, __glutMinWindowHeight;
#endif
/* *INDENT-ON* */

static Bool synchronize = False;

#if defined(WIN32)
void
__glutOpenWin32Connection(char* display)
{
  static char *classname;
  WNDCLASS  wc;
  HINSTANCE hInstance = GetModuleHandle(NULL);
  
  /* make sure we register the window only once */
  if(classname)
    return;

  classname = "GLUT";

  /* clear (important!) and then fill in the window class structure */
  memset(&wc, 0, sizeof(WNDCLASS));
  wc.style         = CS_OWNDC;
  wc.lpfnWndProc   = (WNDPROC)__glutWindowProc;
  wc.hInstance     = hInstance;
  wc.hIcon         = LoadIcon(hInstance, "GLUT_ICON");
  wc.hCursor       = LoadCursor(hInstance, IDC_ARROW);
  wc.hbrBackground = NULL;
  wc.lpszMenuName  = NULL;
  wc.lpszClassName = classname;

  /* fill in a default icon if one isn't specified as a resource */
  if(!wc.hIcon)
    wc.hIcon = LoadIcon(NULL, IDI_WINLOGO);
  
  if(!RegisterClass(&wc)) {
    __glutFatalError("RegisterClass() failed:"
		     "Cannot register GLUT window class.");
  }
 
  __glutScreenWidth     = GetSystemMetrics(SM_CXSCREEN);
  __glutScreenHeight    = GetSystemMetrics(SM_CYSCREEN);
  __glutMinWindowWidth  = GetSystemMetrics(SM_CXMIN);
  __glutMinWindowHeight = GetSystemMetrics(SM_CYMIN);

  /* set the root window to NULL because windows creates a top-level
     window when the parent is NULL.  X creates a top-level window
     when the parent is the root window. */
  __glutRoot            = NULL;

  /* set the display to 1 -- we shouldn't be using this anywhere
     (except as an argument to X calls). */
  __glutDisplay         = (Display*)1;

  /* there isn't any concept of multiple screens in Win32, therefore,
     we don't need to keep track of the screen we're on...it's always
     the same one. */
  __glutScreen          = 0;
}
#else /* !WIN32 */
void
__glutOpenXConnection(char *display)
{
  int errorBase, eventBase;

  __glutDisplay = XOpenDisplay(display);
  if (!__glutDisplay)
    __glutFatalError("could not open display: %s",
      XDisplayName(display));
  if (synchronize)
    XSynchronize(__glutDisplay, True);
  if (!glXQueryExtension(__glutDisplay, &errorBase, &eventBase))
    __glutFatalError(
      "OpenGL GLX extension not supported by display: %s",
      XDisplayName(display));
  __glutScreen = DefaultScreen(__glutDisplay);
  __glutRoot = RootWindow(__glutDisplay, __glutScreen);
  __glutScreenWidth = DisplayWidth(__glutDisplay, __glutScreen);
  __glutScreenHeight = DisplayHeight(__glutDisplay,
    __glutScreen);
  __glutConnectionFD = ConnectionNumber(__glutDisplay);
  __glutWMDeleteWindow = XSGIFastInternAtom(__glutDisplay,
    "WM_DELETE_WINDOW", SGI_XA_WM_DELETE_WINDOW, False);
}
#endif /* WIN32 */

void
__glutInitTime(struct timeval *beginning)
{
  static int beenhere = 0;
  static struct timeval genesis;

  if (!beenhere) {
    GETTIMEOFDAY(&genesis);
    beenhere = 1;
  }
  *beginning = genesis;
}

static void
removeArgs(int *argcp, char **argv, int numToRemove)
{
  int i, j;

  for (i = 0, j = numToRemove; argv[j]; i++, j++) {
    argv[i] = argv[j];
  }
  argv[i] = NULL;
  *argcp -= numToRemove;
}

void APIENTRY 
glutInit(int *argcp, char **argv)
{
  char *display = NULL;
  char *str, *geometry = NULL;
  struct timeval unused;
  int i;

  if (__glutDisplay) {
    __glutWarning("glutInit being called a second time.");
    return;
  }
  /* Determine temporary program name. */
  str = strrchr(argv[0], '/');
  if (str == NULL) {
    __glutProgramName = argv[0];
  } else {
    __glutProgramName = str + 1;
  }

  /* Make private copy of command line arguments. */
  __glutArgc = *argcp;
  __glutArgv = (char **) malloc(__glutArgc * sizeof(char *));
  if (!__glutArgv)
    __glutFatalError("out of memory.");
  for (i = 0; i < __glutArgc; i++) {
    __glutArgv[i] = __glutStrdup(argv[i]);
    if (!__glutArgv[i])
      __glutFatalError("out of memory.");
  }

  /* determine permanent program name */
  str = strrchr(__glutArgv[0], '/');
  if (str == NULL) {
    __glutProgramName = __glutArgv[0];
  } else {
    __glutProgramName = str + 1;
  }

  /* parse arguments for standard options */
  for (i = 1; i < __glutArgc; i++) {
    if (!strcmp(__glutArgv[i], "-display")) {
#if defined(WIN32)
      __glutWarning("-display option invalid for win32 glut.");
#endif /* WIN32 */
      if (++i >= __glutArgc) {
        __glutFatalError(
          "follow -display option with X display name.");
      }
      display = __glutArgv[i];
      removeArgs(argcp, &argv[1], 2);
    } else if (!strcmp(__glutArgv[i], "-geometry")) {
      if (++i >= __glutArgc) {
        __glutFatalError(
          "follow -geometry option with geometry parameter.");
      }
      geometry = __glutArgv[i];
      removeArgs(argcp, &argv[1], 2);
    } else if (!strcmp(__glutArgv[i], "-direct")) {
#if defined(WIN32)
      __glutWarning("-direct option invalid for win32 glut.");
#endif /* WIN32 */
      if (!__glutTryDirect)
        __glutFatalError(
          "cannot force both direct and indirect rendering.");
      __glutForceDirect = GL_TRUE;
      removeArgs(argcp, &argv[1], 1);
    } else if (!strcmp(__glutArgv[i], "-indirect")) {
#if defined(WIN32)
      __glutWarning("-indirect option invalid for win32 glut.");
#endif /* WIN32 */
      if (__glutForceDirect)
        __glutFatalError(
          "cannot force both direct and indirect rendering.");
      __glutTryDirect = GL_FALSE;
      removeArgs(argcp, &argv[1], 1);
    } else if (!strcmp(__glutArgv[i], "-iconic")) {
      __glutIconic = GL_TRUE;
      removeArgs(argcp, &argv[1], 1);
    } else if (!strcmp(__glutArgv[i], "-gldebug")) {
      __glutDebug = GL_TRUE;
      removeArgs(argcp, &argv[1], 1);
    } else if (!strcmp(__glutArgv[i], "-sync")) {
#if defined(WIN32)
      __glutWarning("-indirect option invalid for win32 glut.");
#endif /* WIN32 */
      synchronize = GL_TRUE;
      removeArgs(argcp, &argv[1], 1);
    } else {
      /* Once unknown option encountered, stop command line
         processing. */
      break;
    }
  }
#if defined(WIN32)
  __glutOpenWin32Connection(display);
#else
  __glutOpenXConnection(display);
#endif /* WIN32 */
  if (geometry) {
    int flags, x, y, width, height;

    /* Fix bogus "{width|height} may be used before set"
       warning */
    width = 0;
    height = 0;

    flags = XParseGeometry(geometry, &x, &y,
      (unsigned int *) &width, (unsigned int *) &height);
    if (WidthValue & flags) {
      /* Careful because X does not allow zero or negative
         width windows */
      if (width > 0)
        __glutInitWidth = width;
#if defined(WIN32)
      if (width < __glutMinWindowWidth)
	__glutWarning("requested width is less than minimum allowed.");
#endif /* WIN32 */
    }
    if (HeightValue & flags) {
      /* Careful because X does not allow zero or negative
         height windows */
      if (height > 0)
        __glutInitHeight = height;
#if defined(WIN32)
      if (height < __glutMinWindowHeight)
	__glutWarning("requested height is less than minimum allowed.");
#endif /* WIN32 */
    }
    glutInitWindowSize(__glutInitWidth, __glutInitHeight);
    if (XValue & flags) {
      if (XNegative & flags)
        x = DisplayWidth(__glutDisplay, __glutScreen) +
          x - __glutSizeHints.width;
      /* Play safe: reject negative X locations */
      if (x >= 0)
        __glutInitX = x;
    }
    if (YValue & flags) {
      if (YNegative & flags)
        y = DisplayHeight(__glutDisplay, __glutScreen) +
          y - __glutSizeHints.height;
      /* Play safe: reject negative Y locations */
      if (y >= 0)
        __glutInitY = y;
    }
    glutInitWindowPosition(__glutInitX, __glutInitY);
  }
  __glutInitTime(&unused);
}

/* CENTRY */
void APIENTRY 
glutInitWindowPosition(int x, int y)
{
  __glutInitX = x;
  __glutInitY = y;
  if (x >= 0 && y >= 0) {
    __glutSizeHints.x = x;
    __glutSizeHints.y = y;
    __glutSizeHints.flags |= USPosition;
  } else {
    __glutSizeHints.flags &= ~USPosition;
  }
}

void APIENTRY 
glutInitWindowSize(int width, int height)
{
  __glutInitWidth = width;
  __glutInitHeight = height;
  if (width > 0 && height > 0) {
    __glutSizeHints.width = width;
    __glutSizeHints.height = height;
    __glutSizeHints.flags |= USSize;
  } else {
    __glutSizeHints.flags &= ~USSize;
  }
}

void APIENTRY 
glutInitDisplayMode(unsigned int mask)
{
  __glutDisplayMode = mask;
}

/* ENDCENTRY */
