/*
 * (C)opyright MMV Anselm R. Garbe <garbeam at gmail dot com>
 * See LICENSE file for license details.
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "wmii.h"

/* array indexes for file pointers */
typedef enum {
	F_CTL,
	F_LAST
} FsIndexes;

typedef struct Route Route;
struct Route {
	File dest;
	int src;
};

typedef struct Bind Bind;
struct Bind {
	IXPClient *client;
	Route route[MAX_CONN * MAX_OPEN_FILES];
	File *mount;
	char *prefix;
};

static Bind zero_bind = { 0 };
static Display *dpy;
static IXPServer *ixps;
static char *sockfile = 0;
static File *files[F_LAST];
static Bind **bindings = 0;

static void quit(void *obj, char *arg);
static void bind(void *obj, char *arg);
static void unbind(void *obj, char *arg);
static Bind *path_to_bind(char *path);

static Action acttbl[] = {
	{"quit", quit},
	{"unbind", unbind},
	{"bind", bind},
	{0, 0}
};

static char *version[] = {
	"wmifs - window manager improved filesystem - " VERSION "\n"
		" (C)opyright MMV Anselm R. Garbe\n", 0
};

static void usage()
{
	fprintf(stderr,
			"usage: wmifs -s <socket file> [-v]\n"
			"      -s   socket file\n" "      -v   version info\n");
	exit(1);
}

static void quit(void *obj, char *arg)
{
	int i;
	for (i = 0; bindings && bindings[i]; i++) {
		if (bindings[i]->mount) {
			bindings[i]->mount->content = 0;
			ixp_remove(ixps, bindings[i]->prefix);
			if (ixps->errstr)
				fprintf(stderr, "wmifs: error on quit: remove %s: %s\n",
						bindings[i]->prefix, ixps->errstr);
		}
		/* free stuff */
		if (bindings[i]->prefix)
			free(bindings[i]->prefix);
		free(bindings[i]);
	}
	free(bindings);
	bindings = 0;
	ixps->runlevel = SHUTDOWN;
}

static void _unbind(Bind * b)
{
	bindings =
		(Bind **) detach_item((void **) bindings, b, sizeof(Bind *));

	if (b->mount) {
		b->mount->content = 0;
		ixp_remove(ixps, b->prefix);
		if (ixps->errstr)
			fprintf(stderr, "wmifs: error on _unbind: remove %s: %s\n",
					b->prefix, ixps->errstr);
	}
	/* free stuff */
	deinit_client(b->client);
	free(b->prefix);
	free(b);
}

static void unbind(void *obj, char *arg)
{
	Bind *b = path_to_bind(arg);

	if (!b) {
		fprintf(stderr, "wmifs: unbind: '%s' no such path\n", arg);
		return;
	}
	_unbind(b);
}

static void bind(void *obj, char *arg)
{
	Bind *b = 0;
	char cmd[1024];
	char *sfile;

	if (!arg)
		return;
	cext_strlcpy(cmd, arg, sizeof(cmd));
	sfile = strchr(cmd, ' ');
	if (!sfile) {
		fprintf(stderr,
				"wmifs: bind: '%s' without socket argument, ignoring\n",
				arg);
		return;					/* shortcut with empty argument */
	}
	*sfile = '\0';
	sfile++;
	if (*sfile == '\0') {
		fprintf(stderr,
				"wmifs: bind: '%s' without socket argument, ignoring\n",
				arg);
		return;					/* shortcut with empty argument */
	}
	b = cext_emalloc(sizeof(Bind));
	*b = zero_bind;

	b->client = init_ixp_client(sfile);

	if (!b->client) {
		fprintf(stderr,
				"wmifs: bind: cannot connect to server '%s', ignoring\n",
				sfile);
		free(b);
		return;
	}
	b->prefix = strdup(cmd);
	b->mount = ixp_create(ixps, b->prefix);
	b->mount->content = b->mount;	/* shall be a directory */

	bindings =
		(Bind **) attach_item_end((void **) bindings, b, sizeof(Bind *));
}

static void handle_after_write(IXPServer * s, File * f)
{
	int i;
	size_t len;

	for (i = 0; acttbl[i].name; i++) {
		len = strlen(acttbl[i].name);
		if (!strncmp(acttbl[i].name, (char *) f->content, len)) {
			if (strlen(f->content) > len) {
				acttbl[i].func(0, &((char *) f->content)[len + 1]);
			} else {
				acttbl[i].func(0, 0);
			}
			break;
		}
	}
}

static Bind *path_to_bind(char *path)
{
	int i;
	for (i = 0; bindings && bindings[i]; i++)
		if (!strncmp
			(bindings[i]->prefix, path, strlen(bindings[i]->prefix)))
			return bindings[i];
	return 0;
}

static Bind *fd_to_bind(int fd, int *client_fd)
{
	File *f = fd_to_file(ixps, fd);
	int i, j;

	if (!f)
		return 0;
	for (i = 0; bindings && bindings[i]; i++) {
		for (j = 0; j < MAX_CONN * MAX_OPEN_FILES; j++) {
			if (&bindings[i]->route[j].dest == f) {
				*client_fd = bindings[i]->route[j].src;
				return bindings[i];
			}
		}
	}
	return 0;
}

static File *fixp_create(IXPServer * s, char *path)
{
	Bind *b = path_to_bind(path);
	size_t len;

	if (!b) {
		File *f = ixp_create(s, path);
		return f;
	}
	/* route to b */
	len = strlen(b->prefix);
	b->client->create(b->client, path[len] == '\0' ? "/" : &path[len]);
	if (b->client->errstr) {
		if (!strcmp(b->client->errstr, DEAD_SERVER))
			_unbind(b);
	}
	return 0;
}

static File *fixp_open(IXPServer * s, char *path)
{
	Bind *b = path_to_bind(path);
	int fd;
	size_t len;

	if (!b) {
		File *f = ixp_open(s, path);
		return f;
	}
	/* route to b */
	len = strlen(b->prefix);
	fd = b->client->open(b->client, path[len] == '\0' ? "/" : &path[len]);
	if (b->client->errstr) {
		set_error(s, b->client->errstr);
		if (!strcmp(b->client->errstr, DEAD_SERVER))
			_unbind(b);
		return 0;
	}
	b->route[fd].src = fd;
	return &b->route[fd].dest;
}

static size_t
fixp_read(IXPServer * s, int fd, size_t offset, void *out_buf,
		  size_t out_buf_len)
{
	int cfd;
	Bind *b = fd_to_bind(fd, &cfd);
	size_t result;

	if (!b) {
		result = ixp_read(s, fd, offset, out_buf, out_buf_len);
		return result;
	}
	/* route to b */
	result = seek_read(b->client, cfd, offset, out_buf, out_buf_len);
	if (b->client->errstr) {
		set_error(s, b->client->errstr);
		if (!strcmp(b->client->errstr, DEAD_SERVER))
			_unbind(b);
	}
	return result;
}

static void
fixp_write(IXPServer * s, int fd, size_t offset, void *content,
		   size_t in_len)
{
	int cfd;
	Bind *b = fd_to_bind(fd, &cfd);

	if (!b) {
		ixp_write(s, fd, offset, content, in_len);
		return;
	}
	/* route to b */
	seek_write(b->client, cfd, offset, content, in_len);
	if (b->client->errstr) {
		set_error(s, b->client->errstr);
		if (!strcmp(b->client->errstr, DEAD_SERVER))
			_unbind(b);
	}
}

static void fixp_close(IXPServer * s, int fd)
{
	int cfd;
	Bind *b = fd_to_bind(fd, &cfd);

	if (!b) {
		ixp_close(s, fd);
		return;
	}
	/* route to b */
	b->client->close(b->client, cfd);
	if (b->client->errstr) {
		set_error(s, b->client->errstr);
		if (!strcmp(b->client->errstr, DEAD_SERVER))
			_unbind(b);
	}
}

static void fixp_remove(IXPServer * s, char *path)
{
	Bind *b = path_to_bind(path);
	size_t len;

	if (!b) {
		ixp_remove(s, path);
		return;
	}
	/* route to b */
	len = strlen(b->prefix);
	b->client->remove(b->client, path[len] == '\0' ? "/" : &path[len]);
	if (b->client->errstr) {
		set_error(s, b->client->errstr);
		if (!strcmp(b->client->errstr, DEAD_SERVER))
			_unbind(b);
	}
}

static void check_event(Connection * e)
{
	XEvent ev;
	while (XPending(dpy)) {
		/*
		 * wmifs isn't interested in any X events, so just drop them
		 * all
		 */
		XNextEvent(dpy, &ev);
	}
	/* why check them? because X won't kill wmifs when X dies */
}

static void run()
{
	if (!(files[F_CTL] = ixp_create(ixps, "/ctl"))) {
		perror("wmifs: cannot connect IXP server");
		exit(1);
	}
	files[F_CTL]->after_write = handle_after_write;

	/* routing functions */
	ixps->create = fixp_create;
	ixps->remove = fixp_remove;
	ixps->open = fixp_open;
	ixps->close = fixp_close;
	ixps->read = fixp_read;
	ixps->write = fixp_write;

	/* main event loop */
	run_server_with_fd_support(ixps, ConnectionNumber(dpy),
							   check_event, 0);

	deinit_server(ixps);
}

int main(int argc, char *argv[])
{
	int i;

	/* command line args */
	for (i = 1; (i < argc) && (argv[i][0] == '-'); i++) {
		switch (argv[i][1]) {
		case 'v':
			fprintf(stdout, "%s", version[0]);
			exit(0);
			break;
		case 's':
			if (i + 1 < argc)
				sockfile = argv[++i];
			else
				usage();
			break;
		default:
			usage();
			break;
		}
	}

	if (!getenv("HOME")) {
		fprintf(stderr, "%s",
				"wmifs: $HOME environment variable is not set\n");
		usage();
	}
	/* just for the case X crashes/gets quit */
	dpy = XOpenDisplay(0);
	if (!dpy) {
		fprintf(stderr, "%s", "wmifs: cannot open display\n");
		exit(1);
	}
	ixps = wmii_setup_server(sockfile);

	run();

	return 0;
}