/*

 * (C)opyright MMVI Anselm R. Garbe <garbeam at gmail dot com>

 * See LICENSE file for license details.

 */

#include <errno.h>

#include <stdarg.h>

#include <stdio.h>

#include <stdlib.h>

#include <sys/types.h>

#include <sys/time.h>

#include <X11/cursorfont.h>

#include <X11/Xatom.h>

#include <X11/Xproto.h>

#include "wm.h"

/* X structs */

Display *dpy;

Window root, barwin;

Atom wm_atom[WMLast], net_atom[NetLast];

Cursor cursor[CurLast];

Bool running = True;

Bool sel_screen;

char statustext[1024], tag[256];

int screen, sx, sy, sw, sh, bx, by, bw, bh;

Brush brush = {0};

Client *clients = NULL;

Client *stack = NULL;

static Bool other_wm_running;

static const char version[] = "gridwm - " VERSION ", (C)opyright MMVI Anselm R. Garbe\n";

static int (*x_error_handler) (Display *, XErrorEvent *);

static const char *status[] = {

	"sh", "-c", "echo -n `date '+%Y-%m-%d %H:%M'`" 

	" `uptime | sed 's/.*://; s/,//g'`"

	" `acpi | awk '{print $4}' | sed 's/,//'`", 0

};

static void

usage()

{

	fputs("usage: gridwm [-v]\n", stderr);

	exit(1);

}

static void

scan_wins()

{

	unsigned int i, num;

	Window *wins;

	XWindowAttributes wa;

	Window d1, d2;

	if(XQueryTree(dpy, root, &d1, &d2, &wins, &num)) {

		for(i = 0; i < num; i++) {

			if(!XGetWindowAttributes(dpy, wins[i], &wa))

				continue;

			if(wa.override_redirect || XGetTransientForHint(dpy, wins[i], &d1))

				continue;

			if(wa.map_state == IsViewable)

				manage(wins[i], &wa);

		}

	}

	if(wins)

		XFree(wins);

}

static int

win_property(Window w, Atom a, Atom t, long l, unsigned char **prop)

{

	Atom real;

	int format;

	unsigned long res, extra;

	int status;

	status = XGetWindowProperty(dpy, w, a, 0L, l, False, t, &real, &format,

			&res, &extra, prop);

	if(status != Success || *prop == 0) {

		return 0;

	}

	if(res == 0) {

		free((void *) *prop);

	}

	return res;

}

int

win_proto(Window w)

{

	Atom *protocols;

	long res;

	int protos = 0;

	int i;

	res = win_property(w, wm_atom[WMProtocols], XA_ATOM, 20L,

			((unsigned char **) &protocols));

	if(res <= 0) {

		return protos;

	}

	for(i = 0; i < res; i++) {

		if(protocols[i] == wm_atom[WMDelete])

			protos |= WM_PROTOCOL_DELWIN;

	}

	free((char *) protocols);

	return protos;

}

void

send_message(Window w, Atom a, long value)

{

	XEvent e;

	e.type = ClientMessage;

	e.xclient.window = w;

	e.xclient.message_type = a;

	e.xclient.format = 32;

	e.xclient.data.l[0] = value;

	e.xclient.data.l[1] = CurrentTime;

	XSendEvent(dpy, w, False, NoEventMask, &e);

	XFlush(dpy);

}

/*

 * There's no way to check accesses to destroyed windows, thus

 * those cases are ignored (especially on UnmapNotify's).

 * Other types of errors call Xlib's default error handler, which

 * calls exit().

 */

int

error_handler(Display *dpy, XErrorEvent *error)

{

	if(error->error_code == BadWindow

			|| (error->request_code == X_SetInputFocus

				&& error->error_code == BadMatch)

			|| (error->request_code == X_PolyText8

				&& error->error_code == BadDrawable)

			|| (error->request_code == X_PolyFillRectangle

				&& error->error_code == BadDrawable)

			|| (error->request_code == X_PolySegment

				&& error->error_code == BadDrawable)

			|| (error->request_code == X_ConfigureWindow

				&& error->error_code == BadMatch)

			|| (error->request_code == X_GrabKey

				&& error->error_code == BadAccess))

		return 0;

	fprintf(stderr, "gridwm: fatal error: request code=%d, error code=%d\n",

			error->request_code, error->error_code);

	return x_error_handler(dpy, error); /* may call exit() */

}

/*

 * Startup Error handler to check if another window manager

 * is already running.

 */

static int

startup_error_handler(Display *dpy, XErrorEvent *error)

{

	other_wm_running = True;

	return -1;

}

static void

cleanup()

{

	while(clients)

		unmanage(clients);

	XSetInputFocus(dpy, PointerRoot, RevertToPointerRoot, CurrentTime);

}

int

main(int argc, char *argv[])

{

	int i;

	XSetWindowAttributes wa;

	unsigned int mask;

	Window w;

	XEvent ev;

	fd_set fds;

	struct timeval t, timeout = {

		.tv_usec = 0,

		.tv_sec = STATUSDELAY,

	};

	/* command line args */

	for(i = 1; (i < argc) && (argv[i][0] == '-'); i++) {

		switch (argv[i][1]) {

		case 'v':

			fprintf(stdout, "%s", version);

			exit(0);

			break;

		default:

			usage();

			break;

		}

	}

	dpy = XOpenDisplay(0);

	if(!dpy)

		error("gridwm: cannot connect X server\n");

	screen = DefaultScreen(dpy);

	root = RootWindow(dpy, screen);

	/* check if another WM is already running */

	other_wm_running = False;

	XSetErrorHandler(startup_error_handler);

	/* this causes an error if some other WM is running */

	XSelectInput(dpy, root, SubstructureRedirectMask);

	XFlush(dpy);

	if(other_wm_running)

		error("gridwm: another window manager is already running\n");

	sx = sy = 0;

	sw = DisplayWidth(dpy, screen);

	sh = DisplayHeight(dpy, screen);

	sel_screen = XQueryPointer(dpy, root, &w, &w, &i, &i, &i, &i, &mask);

	XSetErrorHandler(0);

	x_error_handler = XSetErrorHandler(error_handler);

	/* init atoms */

	wm_atom[WMProtocols] = XInternAtom(dpy, "WM_PROTOCOLS", False);

	wm_atom[WMDelete] = XInternAtom(dpy, "WM_DELETE_WINDOW", False);

	net_atom[NetSupported] = XInternAtom(dpy, "_NET_SUPPORTED", False);

	net_atom[NetWMName] = XInternAtom(dpy, "_NET_WM_NAME", False);

	XChangeProperty(dpy, root, net_atom[NetSupported], XA_ATOM, 32,

			PropModeReplace, (unsigned char *) net_atom, NetLast);

	/* init cursors */

	cursor[CurNormal] = XCreateFontCursor(dpy, XC_left_ptr);

	cursor[CurResize] = XCreateFontCursor(dpy, XC_sizing);

	cursor[CurMove] = XCreateFontCursor(dpy, XC_fleur);

	update_keys();

	/* style */

	loadcolors(dpy, screen, &brush, BGCOLOR, FGCOLOR, BORDERCOLOR);

	loadfont(dpy, &brush.font, FONT);

	wa.override_redirect = 1;

	wa.background_pixmap = ParentRelative;

	wa.event_mask = ExposureMask;

	bx = by = 0;

	bw = sw;

	bh = texth(&brush.font);

	barwin = XCreateWindow(dpy, root, bx, by, bw, bh, 0, DefaultDepth(dpy, screen),

			CopyFromParent, DefaultVisual(dpy, screen),

			CWOverrideRedirect | CWBackPixmap | CWEventMask, &wa);

	XDefineCursor(dpy, barwin, cursor[CurNormal]);

	XMapRaised(dpy, barwin);

	brush.drawable = XCreatePixmap(dpy, root, sw, bh, DefaultDepth(dpy, screen));

	brush.gc = XCreateGC(dpy, root, 0, 0);

	pipe_spawn(statustext, sizeof(statustext), dpy, (char **)status);

	draw_bar();

	wa.event_mask = SubstructureRedirectMask | EnterWindowMask \

					| LeaveWindowMask;

	wa.cursor = cursor[CurNormal];

	XChangeWindowAttributes(dpy, root, CWEventMask | CWCursor, &wa);

	scan_wins();

	while(running) {

		if(XPending(dpy) > 0) {

			XNextEvent(dpy, &ev);

			if(handler[ev.type])

				(handler[ev.type]) (&ev); /* call handler */

			continue;

		}

		FD_ZERO(&fds);

		FD_SET(ConnectionNumber(dpy), &fds);

		t = timeout;

		if(select(ConnectionNumber(dpy) + 1, &fds, NULL, NULL, &t) > 0)

			continue;

		else if(errno != EINTR) {

			pipe_spawn(statustext, sizeof(statustext), dpy, (char **)status);

			draw_bar();

		}

	}

	cleanup();

	XCloseDisplay(dpy);

	return 0;

}