/*
 * tkUnix.c --
 *
 *	This file contains procedures that are UNIX/X-specific, and will
 *	probably have to be written differently for Windows or Macintosh
 *	platforms.
 *
 * Copyright (c) 1995 Sun Microsystems, Inc.
 *
 * See the file "license.terms" for information on usage and redistribution of
 * this file, and for a DISCLAIMER OF ALL WARRANTIES.
 */

#include "tkInt.h"
#ifdef HAVE_XSS
#   include <X11/extensions/scrnsaver.h>
#   ifdef __APPLE__
/* Support for weak-linked libXss. */
#	define HaveXSSLibrary()	(&XScreenSaverQueryInfo != NULL)
#   else
/* Other platforms always link libXss. */
#	define HaveXSSLibrary()	(1)
#   endif
#endif

/*
 *----------------------------------------------------------------------
 *
 * TkGetServerInfo --
 *
 *	Given a window, this procedure returns information about the window
 *	server for that window. This procedure provides the guts of the "winfo
 *	server" command.
 *
 * Results:
 *	Sets the interpreter result.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

void
TkGetServerInfo(
    Tcl_Interp *interp,		/* The server information is returned in this
				 * interpreter's result. */
    Tk_Window tkwin)		/* Token for window; this selects a particular
				 * display and server. */
{
    Tcl_SetObjResult(interp, Tcl_ObjPrintf("X%dR%d %s %d",
	    ProtocolVersion(Tk_Display(tkwin)),
	    ProtocolRevision(Tk_Display(tkwin)),
	    ServerVendor(Tk_Display(tkwin)),
	    VendorRelease(Tk_Display(tkwin))));
}

/*
 *----------------------------------------------------------------------
 *
 * TkGetDefaultScreenName --
 *
 *	Returns the name of the screen that Tk should use during
 *	initialization.
 *
 * Results:
 *	Returns the argument or a string that should not be freed by the
 *	caller.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

const char *
TkGetDefaultScreenName(
    Tcl_Interp *interp,		/* Interp used to find environment
				 * variables. */
    const char *screenName)	/* Screen name from command line, or NULL. */
{
    if ((screenName == NULL) || (screenName[0] == '\0')) {
	screenName = Tcl_GetVar2(interp, "env", "DISPLAY", TCL_GLOBAL_ONLY);
    }
    return screenName;
}

/*
 *----------------------------------------------------------------------
 *
 * Tk_UpdatePointer --
 *
 *	Unused function in UNIX
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

void
Tk_UpdatePointer(
    Tk_Window tkwin,		/* Window to which pointer event is reported.
				 * May be NULL. */
    int x, int y,		/* Pointer location in root coords. */
    int state)			/* Modifier state mask. */
{
  /*
   * This function intentionally left blank
   */
}

/*
 *----------------------------------------------------------------------
 *
 * TkpCopyRegion --
 *
 *	Makes the destination region a copy of the source region.
 *	Currently unused on X11.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

extern int XUnionRegion(Region srca, Region srcb, Region dr_return);

void
TkpCopyRegion(
    TkRegion dst,
    TkRegion src)
{
    /* XUnionRegion() in Xlib is optimized to detect copying */
    XUnionRegion((Region)src, (Region)src, (Region)dst);
}

/*
 *----------------------------------------------------------------------
 *
 * TkpBuildRegionFromAlphaData --
 *
 *	Set up a rectangle of the given region based on the supplied alpha
 *	data.
 *
 * Results:
 *	None
 *
 * Side effects:
 *	The region is updated, with extra pixels added to it.
 *
 *----------------------------------------------------------------------
 */

void
TkpBuildRegionFromAlphaData(
    TkRegion region,		/* Region to be updated. */
    unsigned x, unsigned y,	/* Where in region to update. */
    unsigned width, unsigned height,
				/* Size of rectangle to update. */
    unsigned char *dataPtr,	/* Data to read from. */
    unsigned pixelStride,	/* Num bytes from one piece of alpha data to
				 * the next in the line. */
    unsigned lineStride)	/* Num bytes from one line of alpha data to
				 * the next line. */
{
    unsigned char *lineDataPtr;
    unsigned int x1, y1, end;
    XRectangle rect;

    for (y1 = 0; y1 < height; y1++) {
	lineDataPtr = dataPtr;
	for (x1 = 0; x1 < width; x1 = end) {
	    /*
	     * Search for first non-transparent pixel.
	     */

	    while ((x1 < width) && !*lineDataPtr) {
		x1++;
		lineDataPtr += pixelStride;
	    }
	    end = x1;

	    /*
	     * Search for first transparent pixel.
	     */

	    while ((end < width) && *lineDataPtr) {
		end++;
		lineDataPtr += pixelStride;
	    }
	    if (end > x1) {
		rect.x = x + x1;
		rect.y = y + y1;
		rect.width = end - x1;
		rect.height = 1;
		TkUnionRectWithRegion(&rect, region, region);
	    }
	}
	dataPtr += lineStride;
    }
}

/*
 *----------------------------------------------------------------------
 *
 * Tk_GetUserInactiveTime --
 *
 *	Return the number of milliseconds the user was inactive.
 *
 * Results:
 *	The number of milliseconds since the user's latest interaction with
 *	the system on the given display, or -1 if the XScreenSaver extension
 *	is not supported by the client libraries or the X server
 *	implementation.
 *
 * Side effects:
 *	None.
 *----------------------------------------------------------------------
 */

long
Tk_GetUserInactiveTime(
 #ifdef HAVE_XSS
   Display *dpy)		/* The display for which to query the inactive
				 * time. */
#else
  TCL_UNUSED(Display *))
#endif /* HAVE_XSS */
{
    long inactiveTime = -1;
#ifdef HAVE_XSS
    int eventBase, errorBase, major, minor;

    /*
     * Calling XScreenSaverQueryVersion seems to be needed to prevent a crash
     * on some buggy versions of XFree86.
     */

    if (HaveXSSLibrary()
	    && XScreenSaverQueryExtension(dpy, &eventBase, &errorBase)
	    && XScreenSaverQueryVersion(dpy, &major, &minor)) {
	XScreenSaverInfo *info = XScreenSaverAllocInfo();

	if (info == NULL) {
	    /*
	     * We are out of memory.
	     */

	    Tcl_Panic("Out of memory: XScreenSaverAllocInfo failed in Tk_GetUserInactiveTime");
	}
	if (XScreenSaverQueryInfo(dpy, DefaultRootWindow(dpy), info)) {
	    inactiveTime = info->idle;
	}
	XFree(info);
    }
#endif /* HAVE_XSS */
    return inactiveTime;
}

/*
 *----------------------------------------------------------------------
 *
 * Tk_ResetUserInactiveTime --
 *
 *	Reset the user inactivity timer
 *
 * Results:
 *	none
 *
 * Side effects:
 *	The user inactivity timer of the underlaying windowing system is reset
 *	to zero.
 *
 *----------------------------------------------------------------------
 */

void
Tk_ResetUserInactiveTime(
    Display *dpy)
{
    XResetScreenSaver(dpy);
}

/*
 * Local Variables:
 * mode: c
 * c-basic-offset: 4
 * fill-column: 78
 * End:
 */