#include "dwm.h"

/* global variables */
char broken[] = "<broken>";
char stext[256];
int scanner;
int screen;
int sw, sh;           /* X display screen geometry width, height */
int bh, blw = 0;      /* bar geometry */
int lrpad;            /* sum of left and right padding for text */
int (*xerrorxlib)(Display *, XErrorEvent *);
uint numlockmask = 0;
void (*handler[LASTEvent]) (XEvent *) = {
	[ButtonPress]      = buttonpress,
	[ClientMessage]    = clientmessage,
	[ConfigureRequest] = configurerequest,
	[ConfigureNotify]  = configurenotify,
	[DestroyNotify]    = destroynotify,
	[EnterNotify]      = enternotify,
	[Expose]           = expose,
	[FocusIn]          = focusin,
	[KeyPress]         = keypress,
	[MappingNotify]    = mappingnotify,
	[MapRequest]       = maprequest,
	[MotionNotify]     = motionnotify,
	[PropertyNotify]   = propertynotify,
	[UnmapNotify]      = unmapnotify
};

xcb_connection_t *xcon;

Atom wmatom[WMLast] = {0}, netatom[NetLast] = {0};
int running = 1;
Cur *cursor[MouseLast] = {0};
Clr **scheme  = nil;
Display *dpy  = nil;
Drw *drw      = nil;
Monitor *mons = nil, *selmon = nil;
Window root = {0}, wmcheckwin = {0};

/* compile-time check if all tags fit into an uint bit array. */
struct NumTags { char limitexceeded[arrlen(tags) > 31 ? -1 : 1]; };

/* function implementations */
void
arrange(Monitor *m)
{
	if (m)
		showhide(m->stack);
	else for (m = mons; m; m = m->next)
		showhide(m->stack);
	if (m) {
		arrangemon(m);
		restack(m);
	} else for (m = mons; m; m = m->next)
		arrangemon(m);
}

void
arrangemon(Monitor *m)
{
	strncpy(m->ltsymbol, m->lt[m->sellt]->symbol, sizeof m->ltsymbol);
	if (m->lt[m->sellt]->arrange)
		m->lt[m->sellt]->arrange(m);
}

void
buttonpress(XEvent *e)
{
	uint i, x, click;
	Arg arg = {0};
	Client *c;
	Monitor *m;
	XButtonPressedEvent *ev = &e->xbutton;

	click = ClkRootWin;
	/* focus monitor if necessary */
	if ((m = wintomon(ev->window)) && m != selmon) {
		unfocus(selmon->sel, 1);
		selmon = m;
		focus(nil);
	}
	if (ev->window == selmon->barwin) {
		i = x = 0;
		do
			x += TEXTW(tags[i]);
		while (ev->x >= x && ++i < arrlen(tags));
		if (i < arrlen(tags)) {
			click = ClkTagBar;
			arg.ui = 1 << i;
		} else if (ev->x < x + blw)
			click = ClkLtSymbol;
		else if (ev->x > selmon->ww - TEXTW(stext))
			click = ClkStatusText;
		else
			click = ClkWinTitle;
	} else if ((c = wintoclient(ev->window))) {
		focus(c);
		restack(selmon);
		XAllowEvents(dpy, ReplayPointer, CurrentTime);
		click = ClkClientWin;
	}
	for (i = 0; i < arrlen(buttons); i++)
		if (click == buttons[i].click && buttons[i].func && buttons[i].button == ev->button
		&& CLEANMASK(buttons[i].mask) == CLEANMASK(ev->state))
			buttons[i].func(click == ClkTagBar && buttons[i].arg.i == 0 ? &arg : &buttons[i].arg);
}

void
checkotherwm(void)
{
	xerrorxlib = XSetErrorHandler(xerrorstart);
	/* this causes an error if some other window manager is running */
	XSelectInput(dpy, DefaultRootWindow(dpy), SubstructureRedirectMask);
	XSync(dpy, False);
	XSetErrorHandler(xerror);
	XSync(dpy, False);
}

void
cleanup(void)
{
	Arg a = {.ui = ~0};
	Layout foo = { "", nil };
	Monitor *m;
	size_t i;

	view(&a);
	selmon->lt[selmon->sellt] = &foo;
	for (m = mons; m; m = m->next)
		while (m->stack)
			unmanage(m->stack, 0);
	XUngrabKey(dpy, AnyKey, AnyModifier, root);
	while (mons)
		cleanupmon(mons);
	for (i = 0; i < MouseLast; i++)
		drw_cur_free(drw, cursor[i]);
	for (i = 0; i < arrlen(colors); i++)
		free(scheme[i]);
	XDestroyWindow(dpy, wmcheckwin);
	drw_free(drw);
	XSync(dpy, False);
	XSetInputFocus(dpy, PointerRoot, RevertToPointerRoot, CurrentTime);
	XDeleteProperty(dpy, root, netatom[NetActiveWindow]);
}

void
cleanupmon(Monitor *mon)
{
	Monitor *m;

	if (mon == mons)
		mons = mons->next;
	else {
		for (m = mons; m && m->next != mon; m = m->next);
		m->next = mon->next;
	}
	XUnmapWindow(dpy, mon->barwin);
	XDestroyWindow(dpy, mon->barwin);
	free(mon);
}

void
clientmessage(XEvent *e)
{
	XClientMessageEvent *cme = &e->xclient;
	Client *c = wintoclient(cme->window);

	if (!c)
		return;
	if (cme->message_type == netatom[NetWMState]) {
		if (cme->data.l[1] == netatom[NetWMFullscreen]
		|| cme->data.l[2] == netatom[NetWMFullscreen])
			setfullscreen(c, (cme->data.l[0] == 1 /* _NET_WM_STATE_ADD    */
				|| (cme->data.l[0] == 2 /* _NET_WM_STATE_TOGGLE */ && !c->isfullscreen)));
	} else if (cme->message_type == netatom[NetActiveWindow]) {
		if (c != selmon->sel && !c->isurgent)
			seturgent(c, 1);
	}
}

void
configurenotify(XEvent *e)
{
	Monitor *m;
	Client *c;
	XConfigureEvent *ev = &e->xconfigure;
	int dirty;

	/* TODO: updategeom handling sucks, needs to be simplified */
	if (ev->window == root) {
		dirty = (sw != ev->width || sh != ev->height);
		sw = ev->width;
		sh = ev->height;
		if (updategeom() || dirty) {
			drw_resize(drw, sw, bh);
			updatebars();
			for (m = mons; m; m = m->next) {
				for (c = m->clients; c; c = c->next)
					if (c->isfullscreen)
						resizeclient(c, m->mx, m->my, m->mw, m->mh);
				XMoveResizeWindow(dpy, m->barwin, m->wx, m->by, m->ww, bh);
			}
			focus(nil);
			arrange(nil);
		}
	}
}

void
configurerequest(XEvent *e)
{
	Client *c;
	Monitor *m;
	XConfigureRequestEvent *ev = &e->xconfigurerequest;
	XWindowChanges wc;

	if ((c = wintoclient(ev->window))) {
		if (ev->value_mask & CWBorderWidth)
			c->bw = ev->border_width;
		else if (c->isfloating || !selmon->lt[selmon->sellt]->arrange) {
			m = c->mon;
			if (ev->value_mask & CWX) {
				c->oldx = c->x;
				c->x = m->mx + ev->x;
			}
			if (ev->value_mask & CWY) {
				c->oldy = c->y;
				c->y = m->my + ev->y;
			}
			if (ev->value_mask & CWWidth) {
				c->oldw = c->w;
				c->w = ev->width;
			}
			if (ev->value_mask & CWHeight) {
				c->oldh = c->h;
				c->h = ev->height;
			}
			if ((c->x + c->w) > m->mx + m->mw && c->isfloating)
				c->x = m->mx + (m->mw / 2 - WIDTH(c) / 2); /* center in x direction */
			if ((c->y + c->h) > m->my + m->mh && c->isfloating)
				c->y = m->my + (m->mh / 2 - HEIGHT(c) / 2); /* center in y direction */
			if ((ev->value_mask & (CWX|CWY)) && !(ev->value_mask & (CWWidth|CWHeight)))
				configure(c);
			if (ISVISIBLE(c))
				XMoveResizeWindow(dpy, c->win, c->x, c->y, c->w, c->h);
		} else
			configure(c);
	} else {
		wc.x = ev->x;
		wc.y = ev->y;
		wc.width = ev->width;
		wc.height = ev->height;
		wc.border_width = ev->border_width;
		wc.sibling = ev->above;
		wc.stack_mode = ev->detail;
		XConfigureWindow(dpy, ev->window, ev->value_mask, &wc);
	}
	XSync(dpy, False);
}

Monitor *
createmon(void)
{
	Monitor *m;

	m = ecalloc(1, sizeof(Monitor));
	m->tagset[0] = m->tagset[1] = 1;
	m->mfact = mfact;
	m->nmaster = nmaster;
	m->showbar = showbar;
	m->topbar = topbar;
	m->lt[0] = &layouts[0];
	m->lt[1] = &layouts[1 % arrlen(layouts)];
	strncpy(m->ltsymbol, layouts[0].symbol, sizeof m->ltsymbol);
	return m;
}

void
destroynotify(XEvent *e)
{
	Client *c;
	XDestroyWindowEvent *ev = &e->xdestroywindow;

	if ((c = wintoclient(ev->window)))
		unmanage(c, 1);
    else if ((c = swallowing(ev->window)))
        unmanage(c->swallowing, 1);
}

Monitor *
dirtomon(int dir)
{
	Monitor *m = nil;

	if (dir > 0) {
		if (!(m = selmon->next))
			m = mons;
	} else if (selmon == mons)
		for (m = mons; m->next; m = m->next);
	else
		for (m = mons; m->next != selmon; m = m->next);
	return m;
}

void
drawbar(Monitor *m)
{
	int x, w, tw = 0;
	int boxs = drw->fonts->h / 9;
	int boxw = drw->fonts->h / 6 + 2;
	uint i, occ = 0, urg = 0;
	Client *c;

	/* draw status first so it can be overdrawn by tags later */
	if(m == selmon) { /* status is only drawn on selected monitor */
		drw_setscheme(drw, scheme[SchemeNorm]);
		tw = TEXTW(stext) - lrpad + 2; /* 2px right padding */
		drw_text(drw, m->ww - tw, 0, tw, bh, 0, stext, 0);
	}

	for(c = m->clients; c; c = c->next) {
		occ |= c->tags;
		if (c->isurgent)
			urg |= c->tags;
	}
	x = 0;
	for(i = 0; i < arrlen(tags); i++) {
		w = TEXTW(tags[i]);
		drw_setscheme(drw, scheme[m->tagset[m->seltags] & 1 << i ? SchemeSel : SchemeNorm]);
		drw_text(drw, x, 0, w, bh, lrpad / 2, tags[i], urg & 1 << i);
		if (occ & 1 << i)
			drw_rect(drw, x + boxs, boxs, boxw, boxw,
				m == selmon && selmon->sel && selmon->sel->tags & 1 << i,
				urg & 1 << i);
		x += w;
	}
	w = blw = TEXTW(m->ltsymbol);
	drw_setscheme(drw, scheme[SchemeNorm]);
	x = drw_text(drw, x, 0, w, bh, lrpad / 2, m->ltsymbol, 0);

	if((w = m->ww - tw - x) > bh) {
		if (m->sel) {
			drw_setscheme(drw, scheme[m == selmon ? SchemeSel : SchemeNorm]);
			drw_text(drw, x, 0, w, bh, lrpad / 2, m->sel->name, 0);
			if (m->sel->isfloating)
				drw_rect(drw, x + boxs, boxs, boxw, boxw, m->sel->isfixed, 0);
		} else {
			drw_setscheme(drw, scheme[SchemeNorm]);
			drw_rect(drw, x, 0, w, bh, 1, 1);
		}
	}
	drw_map(drw, m->barwin, 0, 0, m->ww, bh);
}

void
drawbars(void)
{
	Monitor *m;

	for (m = mons; m; m = m->next)
		drawbar(m);
}

void
enternotify(XEvent *e)
{
	Client *c;
	Monitor *m;
	XCrossingEvent *ev = &e->xcrossing;

	if ((ev->mode != NotifyNormal || ev->detail == NotifyInferior) && ev->window != root)
		return;
	c = wintoclient(ev->window);
	m = c ? c->mon : wintomon(ev->window);
	if (m != selmon) {
		unfocus(selmon->sel, 1);
		selmon = m;
	} else if (!c || c == selmon->sel)
		return;
	focus(c);
}

void
expose(XEvent *e)
{
	Monitor *m;
	XExposeEvent *ev = &e->xexpose;

	if (ev->count == 0 && (m = wintomon(ev->window)))
		drawbar(m);
}

/* there are some broken focus acquiring clients needing extra handling */
void
focusin(XEvent *e)
{
	XFocusChangeEvent *ev = &e->xfocus;

	if (selmon->sel && ev->window != selmon->sel->win)
		setfocus(selmon->sel);
}

int
getrootptr(int *x, int *y)
{
	int di;
	uint dui;
	Window dummy;

	return XQueryPointer(dpy, root, &dummy, &dummy, x, y, &di, &di, &dui);
}

long
getstate(Window w)
{
	int format;
	long result = -1;
	unsigned char *p = nil;
	unsigned long n, extra;
	Atom real;

	if (XGetWindowProperty(dpy, w, wmatom[WMState], 0L, 2L, False, wmatom[WMState],
		&real, &format, &n, &extra, (unsigned char **)&p) != Success)
		return -1;
	if (n != 0)
		result = *p;
	XFree(p);
	return result;
}

int
gettextprop(Window w, Atom atom, char *text, uint size)
{
	char **list = nil;
	int n;
	XTextProperty name;

	if (!text || size == 0)
		return 0;
	text[0] = '\0';
	if (!XGetTextProperty(dpy, w, &name, atom) || !name.nitems)
		return 0;
	if (name.encoding == XA_STRING)
		strncpy(text, (char *)name.value, size - 1);
	else {
		if (XmbTextPropertyToTextList(dpy, &name, &list, &n) >= Success && n > 0 && *list) {
			strncpy(text, *list, size - 1);
			XFreeStringList(list);
		}
	}
	text[size - 1] = '\0';
	XFree(name.value);
	return 1;
}

void
grabkeys(void)
{
	updatenumlockmask();
	{
		uint i, j;
		uint modifiers[] = { 0, LockMask, numlockmask, numlockmask|LockMask };
		KeyCode code;

		XUngrabKey(dpy, AnyKey, AnyModifier, root);
		for (i = 0; i < arrlen(keys); i++)
			if ((code = XKeysymToKeycode(dpy, keys[i].keysym)))
				for (j = 0; j < arrlen(modifiers); j++)
					XGrabKey(dpy, code, keys[i].mod | modifiers[j], root,
						True, GrabModeAsync, GrabModeAsync);
	}
}

static 
int
isuniquegeom(XineramaScreenInfo *unique, size_t n, XineramaScreenInfo *info)
{
	while (n--)
		if (unique[n].x_org == info->x_org && unique[n].y_org == info->y_org
		&& unique[n].width == info->width && unique[n].height == info->height)
			return 0;
	return 1;
}

void
keypress(XEvent *e)
{
	uint i;
	KeySym keysym;
	XKeyEvent *ev;

	ev = &e->xkey;
	keysym = XkbKeycodeToKeysym(dpy, (KeyCode)ev->keycode, 0, 0);
	for (i = 0; i < arrlen(keys); i++)
		if (keysym == keys[i].keysym
		&& CLEANMASK(keys[i].mod) == CLEANMASK(ev->state)
		&& keys[i].func)
			keys[i].func(&(keys[i].arg));
}

void
manage(Window w, XWindowAttributes *wa)
{
	Client *c, *t = nil, *term = nil;
	Window trans = None;
	XWindowChanges wc;

	c = ecalloc(1, sizeof(Client));
	c->win = w;
    c->pid = winpid(w);
	/* geometry */
	c->x = c->oldx = wa->x;
	c->y = c->oldy = wa->y;
	c->w = c->oldw = wa->width;
	c->h = c->oldh = wa->height;
	c->oldbw = wa->border_width;

	updatetitle(c);
	if (XGetTransientForHint(dpy, w, &trans) && (t = wintoclient(trans))) {
		c->mon = t->mon;
		c->tags = t->tags;
	} else {
		c->mon = selmon;
		applyrules(c);
        term = termof(c);
	}

	if (c->x + WIDTH(c) > c->mon->mx + c->mon->mw)
		c->x = c->mon->mx + c->mon->mw - WIDTH(c);
	if (c->y + HEIGHT(c) > c->mon->my + c->mon->mh)
		c->y = c->mon->my + c->mon->mh - HEIGHT(c);
	c->x = MAX(c->x, c->mon->mx);
	/* only fix client y-offset, if the client center might cover the bar */
	c->y = MAX(c->y, ((c->mon->by == c->mon->my) && (c->x + (c->w / 2) >= c->mon->wx)
		&& (c->x + (c->w / 2) < c->mon->wx + c->mon->ww)) ? bh : c->mon->my);
	c->bw = borderpx;

    selmon->tagset[selmon->seltags] &= ~scratchtag;
    if(!strcmp(c->name, scratchname)) {
        c->mon->tagset[c->mon->seltags] |= c->tags = scratchtag;
        c->isfloating = 1;
        c->x = c->mon->wx + (c->mon->ww / 2 - WIDTH(c) / 2);
        c->y = c->mon->wy + (c->mon->wh / 2 - HEIGHT(c) / 2);
    }

	wc.border_width = c->bw;
	XConfigureWindow(dpy, w, CWBorderWidth, &wc);
	XSetWindowBorder(dpy, w, scheme[SchemeNorm][ColBorder].pixel);
	configure(c); /* propagates border_width, if size doesn't change */
	updatewindowtype(c);
	updatesizehints(c);
	updatewmhints(c);
	XSelectInput(dpy, w, EnterWindowMask|FocusChangeMask|PropertyChangeMask|StructureNotifyMask);
	grabbuttons(c, 0);

	if (!c->isfloating)
		c->isfloating = c->oldstate = trans != None || c->isfixed;
	if (c->isfloating)
		XRaiseWindow(dpy, c->win);

	/* attach(c); */
    attachbottom(c);
	attachstack(c);

	XChangeProperty(dpy, root, netatom[NetClientList], XA_WINDOW, 32, PropModeAppend,
		(unsigned char *) &(c->win), 1);
	XMoveResizeWindow(dpy, c->win, c->x + 2 * sw, c->y, c->w, c->h); /* some windows require this */
	setclientstate(c, NormalState);
	if (c->mon == selmon)
		unfocus(selmon->sel, 0);
	c->mon->sel = c;
	arrange(c->mon);
	XMapWindow(dpy, c->win);
    if (term)
        swallow(term, c);
	focus(nil);
}

void
mappingnotify(XEvent *e)
{
	XMappingEvent *ev = &e->xmapping;

	XRefreshKeyboardMapping(ev);
	if (ev->request == MappingKeyboard)
		grabkeys();
}

void
maprequest(XEvent *e)
{
	static XWindowAttributes wa;
	XMapRequestEvent *ev = &e->xmaprequest;

	if (!XGetWindowAttributes(dpy, ev->window, &wa))
		return;
	if (wa.override_redirect)
		return;
	if (!wintoclient(ev->window))
		manage(ev->window, &wa);
}

void
monocle(Monitor *m)
{
	uint n = 0;
	Client *c;

	for (c = m->clients; c; c = c->next)
		if (ISVISIBLE(c))
			n++;
	if (n > 0) /* override layout symbol */
		snprintf(m->ltsymbol, sizeof m->ltsymbol, "[%d]", n);
	for (c = nexttiled(m->clients); c; c = nexttiled(c->next))
		resize(c, m->wx, m->wy, m->ww - 2 * c->bw, m->wh - 2 * c->bw, 0);
}

void
motionnotify(XEvent *e)
{
	static Monitor *mon = nil;
	Monitor *m;
	XMotionEvent *ev = &e->xmotion;

	if (ev->window != root)
		return;
	if ((m = recttomon(ev->x_root, ev->y_root, 1, 1)) != mon && mon) {
		unfocus(selmon->sel, 1);
		selmon = m;
		focus(nil);
	}
	mon = m;
}

void
propertynotify(XEvent *e)
{
	Client *c;
	Window trans;
	XPropertyEvent *ev = &e->xproperty;

	if ((ev->window == root) && (ev->atom == XA_WM_NAME))
		updatestatus();
	else if (ev->state == PropertyDelete)
		return; /* ignore */
	else if ((c = wintoclient(ev->window))) {
		switch(ev->atom) {
		default: break;
		case XA_WM_TRANSIENT_FOR:
			if (!c->isfloating && (XGetTransientForHint(dpy, c->win, &trans)) &&
				(c->isfloating = (wintoclient(trans)) != nil))
				arrange(c->mon);
			break;
		case XA_WM_NORMAL_HINTS:
			updatesizehints(c);
			break;
		case XA_WM_HINTS:
			updatewmhints(c);
			drawbars();
			break;
		}
		if (ev->atom == XA_WM_NAME || ev->atom == netatom[NetWMName]) {
			updatetitle(c);
			if (c == c->mon->sel)
				drawbar(c->mon);
		}
		if (ev->atom == netatom[NetWMWindowType])
			updatewindowtype(c);
	}
}

Monitor *
recttomon(int x, int y, int w, int h)
{
	Monitor *m, *r = selmon;
	int a, area = 0;

	for (m = mons; m; m = m->next)
		if ((a = INTERSECT(x, y, w, h, m)) > area) {
			area = a;
			r = m;
		}
	return r;
}

void
restack(Monitor *m)
{
	Client *c;
	XEvent ev;
	XWindowChanges wc;

	drawbar(m);
	if (!m->sel)
		return;
	if (m->sel->isfloating || !m->lt[m->sellt]->arrange)
		XRaiseWindow(dpy, m->sel->win);
	if (m->lt[m->sellt]->arrange) {
		wc.stack_mode = Below;
		wc.sibling = m->barwin;
		for (c = m->stack; c; c = c->snext)
			if (!c->isfloating && ISVISIBLE(c)) {
				XConfigureWindow(dpy, c->win, CWSibling|CWStackMode, &wc);
				wc.sibling = c->win;
			}
	}
	XSync(dpy, False);
	while (XCheckMaskEvent(dpy, EnterWindowMask, &ev));
}

void
run(void)
{
	XEvent ev;
	/* main event loop */
	XSync(dpy, False);
	while (running && !XNextEvent(dpy, &ev))
		if (handler[ev.type])
			handler[ev.type](&ev); /* call handler */
}

void
scan(void)
{
	uint i, num;
	Window d1, d2, *wins = nil;
	XWindowAttributes wa;
    char swin[256];

    scanner = 1;

	if (XQueryTree(dpy, root, &d1, &d2, &wins, &num)) {
		for (i = 0; i < num; i++) {
			if (!XGetWindowAttributes(dpy, wins[i], &wa)
			|| wa.override_redirect || XGetTransientForHint(dpy, wins[i], &d1))
				continue;
			if (wa.map_state == IsViewable || getstate(wins[i]) == IconicState)
				manage(wins[i], &wa);
            else if (gettextprop(wins[i], netatom[NetClientList], swin, sizeof swin))
                manage(wins[i], &wa);
		}
		for (i = 0; i < num; i++) { /* now the transients */
			if (!XGetWindowAttributes(dpy, wins[i], &wa))
				continue;
			if (XGetTransientForHint(dpy, wins[i], &d1)
			&& (wa.map_state == IsViewable || getstate(wins[i]) == IconicState))
				manage(wins[i], &wa);
		}
		if (wins)
			XFree(wins);
	}

    scanner = 0;
}

void
setup(void)
{
	int i;
	XSetWindowAttributes wa;
	Atom utf8string;

	/* clean up any zombies immediately */
	sigchld(0);

	/* init screen */
	screen = DefaultScreen(dpy);
	sw   = DisplayWidth(dpy, screen);
	sh   = DisplayHeight(dpy, screen);
	root = RootWindow(dpy, screen);
	drw  = drw_create(dpy, screen, root, sw, sh);
	if (!drw_fontset_create(drw, fonts, arrlen(fonts)))
		fatal("no fonts could be loaded.");

	lrpad = drw->fonts->h;
	bh    = drw->fonts->h + 2;
	updategeom();

	/* init atoms */
	utf8string          = XInternAtom(dpy, "UTF8_STRING", False);
	wmatom[WMProtocols] = XInternAtom(dpy, "WM_PROTOCOLS", False);
	wmatom[WMDelete]    = XInternAtom(dpy, "WM_DELETE_WINDOW", False);
	wmatom[WMState]     = XInternAtom(dpy, "WM_STATE", False);
	wmatom[WMTakeFocus] = XInternAtom(dpy, "WM_TAKE_FOCUS", False);

	netatom[NetActiveWindow]       = XInternAtom(dpy, "_NET_ACTIVE_WINDOW", False);
	netatom[NetSupported]          = XInternAtom(dpy, "_NET_SUPPORTED", False);
	netatom[NetWMName]             = XInternAtom(dpy, "_NET_WM_NAME", False);
	netatom[NetWMState]            = XInternAtom(dpy, "_NET_WM_STATE", False);
	netatom[NetWMCheck]            = XInternAtom(dpy, "_NET_SUPPORTING_WM_CHECK", False);
	netatom[NetWMFullscreen]       = XInternAtom(dpy, "_NET_WM_STATE_FULLSCREEN", False);
	netatom[NetWMWindowType]       = XInternAtom(dpy, "_NET_WM_WINDOW_TYPE", False);
	netatom[NetWMWindowOpacity]    = XInternAtom(dpy, "_NET_WM_WINDOW_OPACITY", False);
	netatom[NetWMWindowTypeDialog] = XInternAtom(dpy, "_NET_WM_WINDOW_TYPE_DIALOG", False);
	netatom[NetClientList]         = XInternAtom(dpy, "_NET_CLIENT_LIST", False);

	/* init cursors */
	cursor[MouseNormal] = drw_cur_create(drw, XC_left_ptr);
	cursor[MouseResize] = drw_cur_create(drw, XC_sizing);
	cursor[MouseMove]   = drw_cur_create(drw, XC_fleur);

	/* init appearance */
	scheme = ecalloc(arrlen(colors), sizeof(Clr *));
	for (i = 0; i < arrlen(colors); i++)
		scheme[i] = drw_scm_create(drw, colors[i], 3);

	/* init bars */
	updatebars();
	updatestatus();

	/* supporting window for NetWMCheck */
	wmcheckwin = XCreateSimpleWindow(dpy, root, 0, 0, 1, 1, 0, 0, 0);
	XChangeProperty(dpy, wmcheckwin, netatom[NetWMCheck], XA_WINDOW, 32,
		PropModeReplace, (uchar *) &wmcheckwin, 1);
	XChangeProperty(dpy, wmcheckwin, netatom[NetWMName], utf8string, 8,
		PropModeReplace, (uchar *) "dwm", 3);
	XChangeProperty(dpy, root, netatom[NetWMCheck], XA_WINDOW, 32,
		PropModeReplace, (uchar *) &wmcheckwin, 1);
	/* EWMH support per view */
	XChangeProperty(dpy, root, netatom[NetSupported], XA_ATOM, 32,
		PropModeReplace, (uchar *) netatom, NetLast);
	XDeleteProperty(dpy, root, netatom[NetClientList]);
	/* select events */
	wa.cursor = cursor[MouseNormal]->cursor;
	wa.event_mask = SubstructureRedirectMask|SubstructureNotifyMask
		|ButtonPressMask|PointerMotionMask|EnterWindowMask
		|LeaveWindowMask|StructureNotifyMask|PropertyChangeMask;
	XChangeWindowAttributes(dpy, root, CWEventMask|CWCursor, &wa);
	XSelectInput(dpy, root, wa.event_mask);
	grabkeys();
	focus(nil);
}


void
sigchld(int unused)
{
	if (signal(SIGCHLD, sigchld) == SIG_ERR)
		fatal("can't install SIGCHLD handler:");
	while (0 < waitpid(-1, nil, WNOHANG));
}

Client *
swallowing(Window w)
{
	Client *c;
	Monitor *m;

	for (m = mons; m; m = m->next) {
		for (c = m->clients; c; c = c->next) {
			if (c->swallowing && c->swallowing->win == w)
				return c;
		}
	}

	return nil;
}

void
tile(Monitor *m)
{
	uint i, n, h, r, mw, my, ty;
	Client *c;

	for (n = 0, c = nexttiled(m->clients); c; c = nexttiled(c->next), n++)
        ;

	if (n == 0)
		return;

	if (n > m->nmaster)
		mw = m->nmaster ? (m->ww+gapx) * m->mfact : 0;
	else
		mw = m->ww - gapx;

	for (i = 0, my = ty = gapx, c = nexttiled(m->clients); c; c = nexttiled(c->next), i++)
		if (i < m->nmaster) {
            r = MIN(n, m->nmaster) - i;
			h = (m->wh - my)/r - gapx;
			resize(c, m->wx + gapx, m->wy + my, mw - (2*c->bw) - gapx, h - (2*c->bw), 0);
			if (my + HEIGHT(c) + gapx < m->wh)
				my += HEIGHT(c) + gapx;
		} else {
            r = (n-i);
			h = (m->wh - ty)/r - gapx;
			resize(c, m->wx + mw + gapx, m->wy + ty, m->ww - mw - (2*c->bw) - (2*gapx), h - (2*c->bw), 0);
			if (ty + HEIGHT(c) + gapx < m->wh)
				ty += HEIGHT(c) + gapx;
		}
}

void
unmapnotify(XEvent *e)
{
	Client *c;
	XUnmapEvent *ev = &e->xunmap;

	if ((c = wintoclient(ev->window))) {
		if (ev->send_event)
			setclientstate(c, WithdrawnState);
		else
			unmanage(c, 0);
	}
}

void
updatebars(void)
{
	Monitor *m;
	XSetWindowAttributes wa = {
		.override_redirect = True,
		.background_pixmap = ParentRelative,
		.event_mask = ButtonPressMask|ExposureMask
	};
	XClassHint ch = {"dwm", "dwm"};
	for (m = mons; m; m = m->next) {
		if (m->barwin)
			continue;
		m->barwin = XCreateWindow(dpy, root, m->wx, m->by, m->ww, bh, 0, DefaultDepth(dpy, screen),
				CopyFromParent, DefaultVisual(dpy, screen),
				CWOverrideRedirect|CWBackPixmap|CWEventMask, &wa);
		XDefineCursor(dpy, m->barwin, cursor[MouseNormal]->cursor);
		XMapRaised(dpy, m->barwin);
		XSetClassHint(dpy, m->barwin, &ch);
	}
}

void
updatebarpos(Monitor *m)
{
	m->wy = m->my;
	m->wh = m->mh;
	if (m->showbar) {
		m->wh -= bh;
		m->by = m->topbar ? m->wy : m->wy + m->wh;
		m->wy = m->topbar ? m->wy + bh : m->wy;
	} else
		m->by = -bh;
}

void
updateclientlist()
{
	Client *c;
	Monitor *m;

	XDeleteProperty(dpy, root, netatom[NetClientList]);
	for (m = mons; m; m = m->next)
		for (c = m->clients; c; c = c->next)
			XChangeProperty(dpy, root, netatom[NetClientList],
				XA_WINDOW, 32, PropModeAppend,
				(unsigned char *) &(c->win), 1);
}

int
updategeom(void)
{
	int dirty = 0;

	if (XineramaIsActive(dpy)) {
		int i, j, n, nn;
		Client *c;
		Monitor *m;
		XineramaScreenInfo *info = XineramaQueryScreens(dpy, &nn);
		XineramaScreenInfo *unique = nil;

		for (n = 0, m = mons; m; m = m->next, n++);
		/* only consider unique geometries as separate screens */
		unique = ecalloc(nn, sizeof(XineramaScreenInfo));
		for (i = 0, j = 0; i < nn; i++)
			if (isuniquegeom(unique, j, &info[i]))
				memcpy(&unique[j++], &info[i], sizeof(XineramaScreenInfo));
		XFree(info);
		nn = j;
		if (n <= nn) { /* new monitors available */
			for (i = 0; i < (nn - n); i++) {
				for (m = mons; m && m->next; m = m->next);
				if (m)
					m->next = createmon();
				else
					mons = createmon();
			}
			for (i = 0, m = mons; i < nn && m; m = m->next, i++)
				if (i >= n
				|| unique[i].x_org != m->mx || unique[i].y_org != m->my
				|| unique[i].width != m->mw || unique[i].height != m->mh)
				{
					dirty  = 1;
					m->num = i;
					m->mx = m->wx = unique[i].x_org;
					m->my = m->wy = unique[i].y_org;
					m->mw = m->ww = unique[i].width;
					m->mh = m->wh = unique[i].height;
					updatebarpos(m);
				}
		} else { /* less monitors available nn < n */
			for (i = nn; i < n; i++) {
				for (m = mons; m && m->next; m = m->next);
				while ((c = m->clients)) {
					dirty = 1;
					m->clients = c->next;
					detachstack(c);
					c->mon = mons;
					/* attach(c); */
                    attachbottom(c);
					attachstack(c);
				}
				if (m == selmon)
					selmon = mons;
				cleanupmon(m);
			}
		}
		free(unique);
	} else
	{ /* default monitor setup */
		if (!mons)
			mons = createmon();
		if (mons->mw != sw || mons->mh != sh) {
			dirty = 1;
			mons->mw = mons->ww = sw;
			mons->mh = mons->wh = sh;
			updatebarpos(mons);
		}
	}
	if (dirty) {
		selmon = mons;
		selmon = wintomon(root);
	}
	return dirty;
}

void
updatenumlockmask(void)
{
	uint i, j;
	XModifierKeymap *modmap;

	numlockmask = 0;
	modmap = XGetModifierMapping(dpy);
	for (i = 0; i < 8; i++)
		for (j = 0; j < modmap->max_keypermod; j++)
			if (modmap->modifiermap[i * modmap->max_keypermod + j]
				== XKeysymToKeycode(dpy, XK_Num_Lock))
				numlockmask = (1 << i);
	XFreeModifiermap(modmap);
}

void
updatestatus(void)
{
	if (!gettextprop(root, XA_WM_NAME, stext, sizeof(stext)))
		strcpy(stext, "dwm-"VERSION);
	drawbar(selmon);
}

pid_t
winpid(Window w)
{
	pid_t result = 0;

	xcb_res_client_id_spec_t spec = {0};
	spec.client = w;
	spec.mask = XCB_RES_CLIENT_ID_MASK_LOCAL_CLIENT_PID;

	xcb_generic_error_t *e = NULL;
	xcb_res_query_client_ids_cookie_t c = xcb_res_query_client_ids(xcon, 1, &spec);
	xcb_res_query_client_ids_reply_t *r = xcb_res_query_client_ids_reply(xcon, c, &e);

	if (!r)
		return (pid_t)0;

	xcb_res_client_id_value_iterator_t i = xcb_res_query_client_ids_ids_iterator(r);
	for (; i.rem; xcb_res_client_id_value_next(&i)) {
		spec = i.data->spec;
		if (spec.mask & XCB_RES_CLIENT_ID_MASK_LOCAL_CLIENT_PID) {
			uint32_t *t = xcb_res_client_id_value_value(i.data);
			result = *t;
			break;
		}
	}

	free(r);

	if (result == (pid_t)-1)
		result = 0;

	return result;
}

Client *
wintoclient(Window w)
{
	Client *c;
	Monitor *m;

	for (m = mons; m; m = m->next)
		for (c = m->clients; c; c = c->next)
			if (c->win == w)
				return c;
	return nil;
}

Monitor *
wintomon(Window w)
{
	int x, y;
	Client *c;
	Monitor *m;

	if (w == root && getrootptr(&x, &y))
		return recttomon(x, y, 1, 1);
	for (m = mons; m; m = m->next)
		if (w == m->barwin)
			return m;
	if ((c = wintoclient(w)))
		return c->mon;
	return selmon;
}

/* There's no way to check accesses to destroyed windows, thus those cases are
 * ignored (especially on UnmapNotify's). Other types of errors call Xlibs
 * default error handler, which may call exit. */
int
xerror(Display *dpy, XErrorEvent *ee)
{
	if (ee->error_code == BadWindow
	|| (ee->request_code == X_SetInputFocus && ee->error_code == BadMatch)
	|| (ee->request_code == X_PolyText8 && ee->error_code == BadDrawable)
	|| (ee->request_code == X_PolyFillRectangle && ee->error_code == BadDrawable)
	|| (ee->request_code == X_PolySegment && ee->error_code == BadDrawable)
	|| (ee->request_code == X_ConfigureWindow && ee->error_code == BadMatch)
	|| (ee->request_code == X_GrabButton && ee->error_code == BadAccess)
	|| (ee->request_code == X_GrabKey && ee->error_code == BadAccess)
	|| (ee->request_code == X_CopyArea && ee->error_code == BadDrawable))
		return 0;
	fprintf(stderr, "dwm: fatal error: request code=%d, error code=%d\n",
		ee->request_code, ee->error_code);
	return xerrorxlib(dpy, ee); /* may call exit */
}

int
xerrordummy(Display *dpy, XErrorEvent *ee)
{
	return 0;
}

/* Startup Error handler to check if another window manager
 * is already running. */
int
xerrorstart(Display *dpy, XErrorEvent *ee)
{
	fatal("dwm: another window manager is already running");
	return -1;
}

int
main(int argc, char *argv[])
{
	if (argc == 2 && !strcmp("-v", argv[1]))
		fatal("dwm-"VERSION);
	else if (argc != 1)
		fatal("usage: dwm [-v]");
	if (!setlocale(LC_CTYPE, "") || !XSupportsLocale())
		fputs("warning: no locale support\n", stderr);
	if (!(dpy = XOpenDisplay(nil)))
		fatal("dwm: cannot open display");
    if (!(xcon = XGetXCBConnection(dpy)))
        fatal("dwm: cannot get xcb connection");

	checkotherwm();
	setup();

#ifdef __OpenBSD__
	if (pledge("stdio rpath proc exec", nil) == -1)
		fatal("pledge");
#endif /* __OpenBSD__ */

	scan();
	run();
	cleanup();

	XCloseDisplay(dpy);
	return 0;
}