/***************************************************************************
 *   Copyright (C) 06/2006 by Olaf Rempel                                  *
 *   razzor@kopf-tisch.de                                                  *
 *                                                                         *
 *   This program is free software; you can redistribute it and/or modify  *
 *   it under the terms of the GNU General Public License as published by  *
 *   the Free Software Foundation; either version 2 of the License, or     *
 *   (at your option) any later version.                                   *
 *                                                                         *
 *   This program is distributed in the hope that it will be useful,       *
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
 *   GNU General Public License for more details.                          *
 *                                                                         *
 *   You should have received a copy of the GNU General Public License     *
 *   along with this program; if not, write to the                         *
 *   Free Software Foundation, Inc.,                                       *
 *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
 ***************************************************************************/
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <sys/stat.h>
#include <errno.h>

#include <rrd.h>

#include "list.h"

#include "logging.h"
#include "configfile.h"
#include "plugins.h"

#define DEFAULT_STEP	10

#define ARGCMAX		64
#define ARGVSIZE	1024

#define RRDTOOL_CREATE	1
#define RRDTOOL_UPDATE	2

#define BUFSIZE		1024

static int append_rra_config(char *buffer, int size, int *pos)
{
	struct conf_section *section;
	struct conf_tupel *tupel;

	int len, rra_cnt = 0;

	section = config_get_section("global");
	if (section == NULL) {
		log_print(LOG_ERROR, "append_ds_config: conf-section 'global' not found");
		return -1;
	}

	list_for_each_entry(tupel, &section->tupel, list) {
		if (strcmp(tupel->option, "rra"))
			continue;

		len = snprintf(buffer + *pos, size - *pos, "%s ", tupel->parameter);
		if (len < 0 || len >= size - *pos) {
			log_print(LOG_ERROR, "append_ds_config: arguments too long");
			return -1;
		}

		*pos += len;
		rra_cnt++;
	}
	return rra_cnt;
}

static int do_rrd(int mode, char *cmd)
{
	int argc;
	char *argv[ARGCMAX];

	argc = strsplit(cmd, argv, ARGCMAX -1);
	argv[argc] = NULL;

	optind = 0;
	rrd_clear_error();

	if (mode == RRDTOOL_CREATE) {
		if (rrd_create(argc, argv) == -1) {
			errno = 0;
			log_print(LOG_ERROR, "rrd_create failed: %s: %s",
					argv[1], rrd_get_error());
			return -1;
		}

	} else if (mode == RRDTOOL_UPDATE) {
		if (rrd_update(argc, argv) == -1) {
			errno = 0;
			log_print(LOG_ERROR, "rrd_update failed: %s: %s",
					argv[1], rrd_get_error());
			return -1;
		}
	}
	return 0;
}

static int rrd_create_file(char *filename, char *plugin_name, int ds_id)
{
	struct sammler_plugin *plugin;
	int pos, step, retval;
	char *ds_def, *buffer;

	plugin = plugin_lookup(plugin_name);
	if (plugin == NULL) {
		log_print(LOG_ERROR, "Plugin not found (%s)", plugin_name);
		return -1;
	}

	ds_def = plugin->get_ds(ds_id);
	if (ds_def == NULL) {
		log_print(LOG_ERROR, "No vaild DS found (%s:%d)", plugin->name, ds_id);
		return -1;
	}

	buffer = malloc(ARGVSIZE);
	if (buffer == NULL) {
		log_print(LOG_ERROR, "append_ds_config: out of memory");
		return -1;
	}

	step = plugin->interval;

	pos = snprintf(buffer, ARGVSIZE, "create %s -s %d %s ", filename, step, ds_def);
	if (pos < 0 || pos >= ARGVSIZE) {
		log_print(LOG_ERROR, "rrd_create_file: arguments too long");
		free(buffer);
		return -1;
	}

	if (append_rra_config(buffer, ARGVSIZE, &pos) <= 0) {
		free(buffer);
		return -1;
	}

	retval = do_rrd(RRDTOOL_CREATE, buffer);
	free(buffer);

	return retval;
}

static int rrd_update_file(char *filename, char *values)
{
	int pos, retval;
	char *buffer;

	buffer = malloc(ARGVSIZE);
	if (buffer == NULL) {
		log_print(LOG_ERROR, "append_ds_config: out of memory");
		return -1;
	}

	pos = snprintf(buffer, ARGVSIZE, "update %s %lu:%s", filename, time(NULL), values);
	if (pos < 0 || pos >= ARGVSIZE) {
		log_print(LOG_ERROR, "rrd_update_file: arguments too long");
		free(buffer);
		return -1;
	}

	retval = do_rrd(RRDTOOL_UPDATE, buffer);
	free(buffer);

	return retval;
}

static int check_create_dir(char *dir)
{
	struct stat statbuf;
	if (stat(dir, &statbuf) == -1) {
		if (errno == ENOENT) {
			errno = 0;
			if (mkdir(dir, 0755) == -1) {
				log_print(LOG_ERROR, "check_create_dir: mkdir(%s)", dir);
				return -1;
			}

		} else {
			log_print(LOG_ERROR, "check_create_dir: stat(%s)", dir);
			return -1;
		}

	} else if (!S_ISDIR (statbuf.st_mode)) {
		log_print(LOG_ERROR, "check_create_dir: stat(%s): Not a directory!", dir);
		return -1;
	}
	return 0;
}

static int create_parent_dirs(char *filename)
{
	char *lastslash, *nextslash = filename;

	lastslash = strrchr(filename, '/');
	if (lastslash == NULL) {
		log_print(LOG_ERROR, "create_parent_dirs: invalid file name");
		return -1;
	}

	*lastslash = '\0';

	while (1) {
		if (strchr(nextslash, '/') == NULL) {
			if (*lastslash == '\0')
				*lastslash = '/';
			else
				break;
		}
		nextslash = strchr(nextslash, '/');

		*nextslash = '\0';
		if (filename != nextslash) {
			if (check_create_dir(filename) == -1) {
				*nextslash = '/';
				*lastslash = '/';
				return -1;
			}
		}
		*nextslash++ = '/';
	}
	return 0;
}

void rrd_submit(char *hostname, char *plugin, char *filename, int ds_id, char *data)
{
	struct stat statbuf;
	static char *rrd_dir = NULL;

	char *fullfile;
	int len;

	if (rrd_dir == NULL)
		rrd_dir = config_get_string("global", "rrd_dir", ".");

	fullfile = malloc(BUFSIZE);
	if (fullfile == NULL) {
		log_print(LOG_ERROR, "rrd_submit: out of memory");
		return;
	}

	len = snprintf(fullfile, BUFSIZE, "%s/%s/%s", rrd_dir, hostname, filename);
	if (len < 0 || len >= BUFSIZE) {
		log_print(LOG_ERROR, "rrd_submit: arguments too long");
		free(fullfile);
		return;
	}

	if (stat(fullfile, &statbuf) == -1) {
		if (errno == ENOENT) {
			errno = 0;

			if (create_parent_dirs(fullfile) == -1) {
				free(fullfile);
				return;
			}

			if (rrd_create_file(fullfile, plugin, ds_id) == -1) {
				free(fullfile);
				return;
			}

		} else {
			log_print(LOG_ERROR, "rrd_submit: stat(%s):", fullfile);
			free(fullfile);
			return;
		}

	} else if (!S_ISREG (statbuf.st_mode)) {
		log_print(LOG_ERROR, "rrd_submit: stat(%s): Not a regular file!", fullfile);
		free(fullfile);
		return;
	}

	rrd_update_file(fullfile, data);
	free(fullfile);
}