/* Simple program to toggle Translucency property
   Based on 'transset' by  Matthew Hawn
   With some additional features to make it more automatic and integrated
   The purpos is to bind it from your wm to a key or mouse-button

   License: Use however you want.
   Authors: 
	Matthew Hawn
	Daniel Forchheimer
	Andreas Kohn
	Roman Divacky
*/

#define VERSIONSTR "6"
#define RELEASEDATESTR "2007-09-21"

#include <stdio.h>
#include <X11/Xlib.h>
#include <X11/Xatom.h>
#include "dsimple.h"
#include <stdlib.h>
#include <getopt.h>
#include <string.h>
#include <sys/types.h>
#include <regex.h>

Window target_win;

/* needed by dsimple.c */

void usage()
{
  fprintf(stderr,"usage: transset-df [-options ...] [opacity]\n");
  fprintf(stderr,"options:\n");

  fprintf(stderr,
	  "    -h, --help           display this message\n");
  fprintf(stderr,
	  "    -t, --toggle         force toggle of opacity\n");
  fprintf(stderr,
	  "    -c, --click          select by clicking on window (default)\n");
  fprintf(stderr,
	  "    -p, --point          select the window currently under the cursor\n");
  fprintf(stderr,
	  "    -a, --actual         select the actual window\n");
  fprintf(stderr,
	  "    -n, --name NAME      select by name, NAME is matched as regular expression\n");
  fprintf(stderr,
	  "    --no-regex           don't use regular expression for matching name\n");
  fprintf(stderr,
	  "    -i, --id             select by window id\n");
  fprintf(stderr,
	  "        --inc            increase by the given opacity\n");
  fprintf(stderr,
	  "        --dec            decrease by given opacity\n");
  fprintf(stderr,
	  "    -m, --min OPACITY    minimum possible opacity (default = 0)\n");
  fprintf(stderr,
	  "    -x, --max OPACITY    maximum possible opacity (default = 1)\n");
  fprintf(stderr,
	  "    -v, --verbose        print some debug info\n");
  fprintf(stderr,
	  "    -V, --version        print version number\n");

  exit(1);
}

#define OPAQUE	0xffffffff
#define OPACITY	"_NET_WM_WINDOW_OPACITY"

/* returns the highest parent of child that is not the root-window */
Window get_top_window(Display *dpy,Window child) {
		Window parent;
		Window root;
		Window *child_list;
		unsigned int num_children;
		
	 	if (!XQueryTree(dpy, child, &root, &parent, &child_list,
				  &num_children))
  	  Fatal_Error("Can't query window tree.");
		if(parent==root) return child;
		
		while(parent!=root) {
			child = parent;
	 		if (!XQueryTree(dpy, child, &root, &parent, &child_list,
				  &num_children))
			Fatal_Error("Can't query window tree.");

		}
		return child;
}

/* returns the actual window */
Window get_actual_window(Display *dpy)
{
    int i;
    Window w;

    XGetInputFocus(dpy, &w, &i);
    return get_top_window(dpy, w);
}

/* nothing fancy */
int main(int argc, char **argv)
{
  int gotd = 0;
  double d;
  unsigned int opacity;
  unsigned int current_opacity;
  int select_method = 0; // 0 = click, 1 = point, 2 = id, 3 = name
  int flag_toggle=0;
  int flag_increase=0;
  int flag_decrease=0;
	int flag_verbose=0;
	int flag_no_regex=0;
  int o;
  float min=0,max=1;
	char *idstr,*namestr;
	char *windowname=NULL;
	
  int options_index=0;
  static struct option long_options[] = {
    {"toggle",0,NULL,'t'},
    {"help",0,NULL,'h'},
    {"point",0,NULL,'p'},
    {"actual",0,NULL,'a'},
    {"click",0,NULL,'c'},
    {"id",1,NULL,'i'},
    {"name",1,NULL,'n'},
    {"inc",0,NULL,'1'},
    {"dec",0,NULL,'2'},
    {"min",1,NULL,'m'},
    {"max",1,NULL,'x'},
    {"no-regex",0,NULL,'4'},
    {"version",0,NULL,'V'},
    {"verbose",0,NULL,'v'},
    {0,0,0,0}
  };
  unsigned char *data;

  Atom actual;
  int format;
  unsigned long n, left;

  /* wonderful utility */
  Setup_Display_And_Screen(&argc, argv);

	/* parse arguments */
  while ((o = getopt_long(argc, argv, "thapci:n:vVm:x:123",long_options,&options_index)) != -1)
    {
      switch (o) {
      case 't':
				flag_toggle=1;
			break;
      case 'h':
				usage();
			break;
      case 'c':
				select_method=0;
			break;
      case 'p':
				select_method=1;
			break;
      case 'i':
				idstr = malloc(strlen(optarg)+1);
				idstr = optarg;
				select_method=2;
			break;
      case 'n':
				namestr = malloc(strlen(optarg)+1);
				namestr = optarg;
				select_method=3;
			break;
      case 'a':
				select_method=4;
			break;
      case '1':
				flag_increase=1;
			break;
      case '2':
				flag_decrease=1;
			break;
      case 'v':
				flag_verbose=1;
			break;
      case '4':
				flag_no_regex=1;
			break;
      case 'm':
				min = atof(optarg);
			break;
      case 'x':
				max = atof(optarg);
			break;
      case 'V':
				fprintf(stderr,"version: %s\nreleased: %s\n",VERSIONSTR,RELEASEDATESTR);
				exit(1);
			break;
      default:
				usage();
      }
    }
  
  if(optind<argc)
  {
    d = atof (argv[optind]);
    gotd = 1;
  }

  /* select the window to make transparent */
  if(select_method==1) {
    /* don't wait for click */
		if(flag_verbose) printf("Selecting window by click\n");
    target_win = Get_Window_Under_Cursor(dpy);
	} else if(select_method==2) {
    /* select by id, pretty much ripped from dsimple.c */
		if(flag_verbose) printf("Selecting window by id\n");
		sscanf(idstr, "0x%lx", &target_win);
		if (!target_win)
		  sscanf(idstr, "%ld", &target_win);
		if (!target_win) {
		  fprintf(stderr,"Invalid window id format: %s.\n", idstr);
			exit(0);
		}
		if(flag_verbose) printf("Selected 0x%x, trying to get top parent ... ",(unsigned int)target_win);
		target_win = get_top_window(dpy,target_win);
		if(flag_verbose) printf("found 0x%x\n",(unsigned int)target_win);
		
	} else if(select_method==3) {
    /* select by name, pretty much ripped from dsimple.c */
		if(flag_verbose) printf("Selecting window by name\n");

		if(flag_no_regex)
			target_win = Window_With_Name(dpy, RootWindow(dpy, screen),namestr);
		else
			target_win = Window_With_Name_Regex(dpy, RootWindow(dpy, screen),namestr);
		
		if (!target_win) {
			  fprintf(stderr,"No window matching %s exists!\n",namestr);
				exit(0);
		}
		/* store the matched window name*/
		XFetchName(dpy,target_win,&windowname);

		if(flag_verbose) printf("Selected 0x%x, trying to get top parent ... ",(unsigned int)target_win);
		target_win = get_top_window(dpy,target_win);
		if(flag_verbose) printf("found 0x%x\n",(unsigned int)target_win);
		
  } else if(select_method==4) {
     target_win = get_actual_window(dpy);
  } else {
    /* grab mouse and return window that is next clicked */
    target_win = Select_Window(dpy);
  }
  
  if (!gotd) d=0.75;

  /* get property */
  XGetWindowProperty(dpy, target_win, XInternAtom(dpy, OPACITY, False), 
		     0L, 1L, False, XA_CARDINAL, &actual, &format, &n, &left, 
		     (unsigned char **) &data);
  
  if (data != None)
    {
      memcpy (&current_opacity, data, sizeof (unsigned int));
      XFree(( void *) data );
      if(flag_verbose) printf("Found transparency: %g\n", (double) opacity / OPAQUE);
    }
  else
    current_opacity = OPAQUE;
  
  if(flag_increase) {
    d = (double)current_opacity/OPAQUE + d; 
  } else if(flag_decrease) {
    d = (double)current_opacity/OPAQUE - d;
  }
 //printf("%f\n",d);
  /* check min and max */
  if(d<min) d=min;
  if(d>max) d=max;

  opacity = (unsigned int) (d * OPAQUE);

  /* for user-compability with transset */
  if(!gotd) flag_toggle=1;
  
  /* toggle */ 
  if(flag_toggle)
    if (current_opacity != OPAQUE)
      opacity = OPAQUE;

  //  printf ("opacity 0x%x\n", opacity);
  if (opacity == OPAQUE)
  	XDeleteProperty (dpy, target_win, XInternAtom(dpy, OPACITY, False));
  /* set it */
	else
    XChangeProperty(dpy, target_win, XInternAtom(dpy, OPACITY, False), 
		    XA_CARDINAL, 32, PropModeReplace, 
		    (unsigned char *) &opacity, 1L);
  XSync(dpy, False);

	printf("Set Property to %g", (double) opacity / OPAQUE);
  if(windowname) printf(" on \n%s\n",windowname);
	else printf("\n");
	if(flag_verbose) printf("Propery set on: 0x%x\n",(unsigned int)target_win);
  /* all done, wasn't that simple */
  return 0;
}