#include "xsimple.h"
#include <stdio.h>
#include <stdlib.h>
#include <signal.h>

XVARS xv;

static Atom wm_protocols, wm_delete_window;


static void cleanup(void)
{
    XCloseDisplay(xv.d);
}

static void sighandler(int sig)
{
    xv.sig++;
}

void xinit(char *appname, char *classname, char *winname,
	int x, int y, int width, int height, int resizable,
	char *bgcolor, char *fgcolor, long evtmask)
{
    unsigned long bgc, fgc;
    XClassHint *ch;
    XSizeHints *sh;

    if (! (xv.d = XOpenDisplay(NULL))) {
	fprintf(stderr, "xinit(): Error opening display\n");
	exit(1);
    }
    atexit(cleanup);

    xv.s = DefaultScreen(xv.d);
    xv.v = DefaultVisual(xv.d, xv.s);
    xv.depth = DefaultDepth(xv.d, xv.s);
    xv.cmap = DefaultColormap(xv.d, xv.s);
    xv.x = x; xv.y = y;
    xv.dwidth = DisplayWidth(xv.d, xv.s);
    xv.dheight = DisplayHeight(xv.d, xv.s);
    xv.width = (width == 0 ? xv.dwidth : width);
    xv.height = (height == 0 ? xv.dheight : height);
    xv.bwidth = xv.twidth = 0;

    if ((xv.v->class != TrueColor) || (xv.depth != 16 && xv.depth != 24)) {
	fprintf(stderr, "xinit(): Unsupported visual\n");
	exit(1);
    }

    xv.sig = 0;
    signal(SIGHUP, sighandler);
    signal(SIGINT, sighandler);
    signal(SIGTERM, sighandler);

    initcolors();

    bgc = getnamedcolor(bgcolor, NULL); fgc = getnamedcolor(fgcolor, NULL);

    xv.w = XCreateSimpleWindow(xv.d, DefaultRootWindow(xv.d), xv.x, xv.y,
	    xv.width, xv.height, 0, fgc, bgc);

    XSelectInput(xv.d, xv.w, StructureNotifyMask | ExposureMask |
	    KeyPressMask | KeyReleaseMask | evtmask);

    xv.pmap = mkpixmap(resizable ? xv.dwidth : xv.width,
	    resizable ? xv.dheight : xv.height, xv.depth);
    xv.gc = XCreateGC(xv.d, xv.pmap, 0, NULL);

    ch = XAllocClassHint();
    ch->res_name = appname;
    ch->res_class = classname;
    XSetClassHint(xv.d, xv.w, ch);
    settitle(winname);

    sh = XAllocSizeHints();
    sh->flags = USPosition | USSize | PMaxSize | (resizable ? 0 : PMinSize);
    sh->x = xv.x; sh->y = xv.y; sh->width = xv.width; sh->height = xv.height;
    if (resizable) {
	sh->max_width = xv.dwidth; sh->max_height = xv.dheight;
    } else {
	sh->min_width = sh->max_width = xv.width;
	sh->min_height = sh->max_height = xv.height;
    }
    XSetWMNormalHints(xv.d, xv.w, sh);

    wm_protocols = XInternAtom(xv.d, "WM_PROTOCOLS", False);
    wm_delete_window = XInternAtom(xv.d, "WM_DELETE_WINDOW", False);
    XSetWMProtocols(xv.d, xv.w, &wm_delete_window, 1);

    XMapWindow(xv.d, xv.w);
}

int getevent(XEvent *event)
{
    XEvent e;

    if (xv.sig) exit(0);

    if (! XPending(xv.d))
	return 0;
    XNextEvent(xv.d, &e);

    switch (e.type) {
	case ReparentNotify:
	    {
		Window rootw, parentw = xv.w, currentw, child, *children;
		int nchildren;
		int x1, y1, x2, y2;
		XTranslateCoordinates(xv.d, xv.w, DefaultRootWindow(xv.d),
			0, 0, &x1, &y1, &child);
		do {
		    currentw = parentw;
		    XQueryTree(xv.d, currentw, &rootw, &parentw, &children,
			    &nchildren);
		    XFree(children);
		} while (parentw != rootw);
		XTranslateCoordinates(xv.d, currentw, DefaultRootWindow(xv.d),
			0, 0, &x2, &y2, &child);
		xv.bwidth = x1 - x2; xv.twidth = y1 - y2;
	    }
	    break;
	case ConfigureNotify:
	    {
		XConfigureEvent *ce = (XConfigureEvent *)&e;
		Window child;
		XTranslateCoordinates(xv.d, xv.w, DefaultRootWindow(xv.d),
			0, 0, &xv.x, &xv.y, &child);
		xv.width = ce->width; xv.height = ce->height;
	    }
	    break;
	case ClientMessage:
	    if (e.xclient.message_type == wm_protocols &&
		    e.xclient.data.l[0] == wm_delete_window)
		exit(0);
	    break;
    }

    *event = e;
    return 1;
}

void doexpose(XEvent *event)
{
    for (;;) {
	XExposeEvent *ee = (XExposeEvent *)event;
	update(ee->x, ee->y, ee->width, ee->height);
	if (! ee->count)
	    break;
	XNextEvent(xv.d, event);
    }
}

void update(int x, int y, int width, int height)
{
    if (x == 0 && y == 0 && width == 0 && height == 0) {
	width = xv.width;
	height = xv.height;
    }
    XSync(xv.d, False);
    XCopyArea(xv.d, xv.pmap, xv.w, xv.gc, x, y, width, height, x, y);
    XSync(xv.d, False);
}
.