/*   Copyright (c) 2007, David Josephsen
 *   All rights reserved.
 *  
 *   Redistribution and use in source and binary forms, with or without
 *   modification, are permitted provided that the following conditions are met:
 *       * Redistributions of source code must retain the above copyright
 *         notice, this list of conditions and the following disclaimer.
 *       * Redistributions in binary form must reproduce the above copyright
 *         notice, this list of conditions and the following disclaimer in the
 *         documentation and/or other materials provided with the distribution.
 *       * Neither the name of David Josephsen nor the
 *         names of this packages contributors may be used to endorse or promote products
 *         derived from this software without specific prior written permission.
 *  
 *   THIS SOFTWARE IS PROVIDED BY David Josephsen ``AS IS'' AND ANY
 *   EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 *   WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 *   DISCLAIMED. IN NO EVENT SHALL David Josephsen BE LIABLE FOR ANY
 *   DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 *   (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 *   LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 *   ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 *   SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/ 


#ifndef NSCORE
#define NSCORE
#endif

/* include (minimum required) event broker header files */
#include "../include/nebmodules.h"
#include "../include/nebcallbacks.h"

/* include other event broker header files that we need for our work */
#include "../include/nebstructs.h"
#include "../include/broker.h"

/* include some Nagios stuff as well */
#include "../include/config.h"
#include "../include/common.h"
#include "../include/nagios.h"
#include "../include/objects.h"


/* specify event broker API version (required) */
NEB_API_VERSION(CURRENT_NEB_API_VERSION);

/*globals*/
void *nagfs_module_handle = NULL;
char *nagfs_home = "/usr/share/nagios/status";
char *nagfs_fs_home = "/usr/share/nagios/status/local";
char *nagfs_meta_home = "/usr/share/nagios/status/meta";
char *nagfs_mesh_home = "/usr/share/nagios/status/mesh";

/* Nagfs Functions */
void nagfs_reminder_message(char *);
int nagfs_handle_data(int,void *);
int nagfs_write_service_status(char *, char *, int, int);
int nagfs_write_host_status(char *, int, int);
int nagfs_check_for_softfiles(char *);


/* this function gets called when the module is loaded by the event broker */
int nebmodule_init(int flags, char *args, nebmodule *handle){

	/* save our handle */
	nagfs_module_handle = handle;

	/* log module info to the Nagios log file */
	write_to_all_logs("nagfs: Copyright (c) 2007 Dave Josephsen (dave@skeptech.org)",NSLOG_INFO_MESSAGE);
	
	/* register to be notified of certain events... */
	neb_register_callback(NEBCALLBACK_SERVICE_STATUS_DATA,nagfs_module_handle,0,nagfs_handle_data);
	neb_register_callback(NEBCALLBACK_HOST_STATUS_DATA,nagfs_module_handle,0,nagfs_handle_data);

	return OK;
        }


/* this function gets called when the module is unloaded by the event broker */
int nebmodule_deinit(int flags, int reason){
	char temp_buffer[1024];

	/* deregister for all events we previously registered for... */
	neb_deregister_callback(NEBCALLBACK_AGGREGATED_STATUS_DATA,nagfs_handle_data);

	/* log a message to the Nagios log file */
	snprintf(temp_buffer,sizeof(temp_buffer)-1,"nagfs: Goodbye world!\n");
	temp_buffer[sizeof(temp_buffer)-1]='\x0';
	write_to_all_logs(temp_buffer,NSLOG_INFO_MESSAGE);

	return OK;
        }


/* handle data from Nagios daemon */
int nagfs_handle_data(int event_type, void *data){
	nebstruct_service_status_data *ssdata=NULL;
	nebstruct_host_status_data *hsdata=NULL;
	service *svc=NULL;
	host *hst=NULL;
	char temp_buffer[1024];

	/* what type of event/data do we have? */
	switch(event_type){

	case NEBCALLBACK_SERVICE_STATUS_DATA:
	//service status data occurs every time a check runs. We use this to update the service file in each hosts directory.

			ssdata=(nebstruct_service_status_data *)data;
			//ss data gives us a pointer directly to the service object
			svc=ssdata->object_ptr;
			nagfs_write_service_status(svc->host_name, svc->description, svc->current_state, svc->state_type );

		break;

	case NEBCALLBACK_HOST_STATUS_DATA:
	//service status data occurs every time a host check runs. We use this to update the HOST file.

			hsdata=(nebstruct_host_status_data *)data;
			//ss data gives us a pointer directly to the service object
			hst=hsdata->object_ptr;
			nagfs_write_host_status(hst->name, hst->current_state, hst->state_type );

		break;

	default:
			snprintf(temp_buffer,sizeof(temp_buffer)-1,"nagfs: just got some unknown data. Wierd.." );
			temp_buffer[sizeof(temp_buffer)-1]='\x0';
			write_to_all_logs(temp_buffer,NSLOG_INFO_MESSAGE);
		break;
	        }

	return OK;
        }

/* this function writes service status data from status update events to the
 * status filesystem. */
int nagfs_write_service_status(char *host_name, char *service_description, int state, int state_type){

	int bufsize = 1024;
	char host_path[bufsize];
   char service_path[bufsize];
   char soft[bufsize];
	char temp_buffer[bufsize];
	DIR *dp;
	FILE *outfile;

	snprintf( host_path,bufsize,"%s/%s", nagfs_fs_home, host_name);
	snprintf( soft,bufsize,"%s/%s/%s.soft", nagfs_fs_home, host_name, service_description);

	//are we writing a normal file or a .soft file
	switch(state_type){

	case 0:

			//the service is in a soft state write a .soft file
			snprintf( service_path,bufsize,"%s/%s/%s.soft", nagfs_fs_home, host_name, service_description);

		break;

	case 1:

			//the service is in a hard state
			snprintf( service_path,bufsize,"%s/%s/%s", nagfs_fs_home, host_name, service_description);
			//delete any soft files if they exist
			if((nagfs_check_for_softfiles(soft)) != OK){
			snprintf(temp_buffer,sizeof(temp_buffer)-1,"nagfs: couldn't remove %s",service_path );
			temp_buffer[sizeof(temp_buffer)-1]='\x0';
			write_to_all_logs(temp_buffer,NSLOG_INFO_MESSAGE);
			}

		break;

	default:
			snprintf(temp_buffer,sizeof(temp_buffer)-1,"nagfs: just got an unknown state type. Wierd.." );
			temp_buffer[sizeof(temp_buffer)-1]='\x0';
			write_to_all_logs(temp_buffer,NSLOG_INFO_MESSAGE);
		break;
	        }

	//create the directory if it doesn't exist 
	if((dp = opendir(host_path)) == NULL) {
   	if(( mkdir( host_path, S_IRWXU|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH )) != OK){
			snprintf(temp_buffer,sizeof(temp_buffer)-1,"nagfs: Couldn't create the directory: %s",host_path);
			temp_buffer[sizeof(temp_buffer)-1]='\x0';
			write_to_all_logs(temp_buffer,NSLOG_INFO_MESSAGE);
		}
	}else{
		closedir(dp);
	}

   //write the file
   if(( outfile=fopen(service_path,"w")) == NULL){
			snprintf(temp_buffer,sizeof(temp_buffer)-1,"nagfs: Couldn't open file for writing: %s",service_path);
			temp_buffer[sizeof(temp_buffer)-1]='\x0';
			write_to_all_logs(temp_buffer,NSLOG_INFO_MESSAGE);
	}
   fprintf(outfile,"%i",state);
   fclose(outfile);
   return OK;
}

/* same like above, just for hosts */
int nagfs_write_host_status(char *host_name, int state, int state_type){
	int bufsize = 1024;
	char host_path[bufsize];
   char host_file[bufsize];
   char soft[bufsize];
	char temp_buffer[bufsize];
	DIR *dp;
	FILE *outfile;

	snprintf( host_path,bufsize,"%s/%s", nagfs_fs_home, host_name);
	snprintf( soft,bufsize,"%s/%s/HOST.soft", nagfs_fs_home, host_name);

	//are we writing a normal file or a .soft file
	switch(state_type){

	case 0:

			//the service is in a soft state write a .soft file
			snprintf( host_file,bufsize,"%s/%s/HOST.soft", nagfs_fs_home, host_name );

		break;

	case 1:
			//the host is in a hard state
			snprintf( host_file,bufsize,"%s/%s/HOST", nagfs_fs_home, host_name );
			//delete softfiles if they exist
			if((nagfs_check_for_softfiles(soft)) != OK){
			snprintf(temp_buffer,sizeof(temp_buffer)-1,"nagfs: couldn't remove %s",host_file );
			temp_buffer[sizeof(temp_buffer)-1]='\x0';
			write_to_all_logs(temp_buffer,NSLOG_INFO_MESSAGE);
			}

		break;

	default:
			snprintf(temp_buffer,sizeof(temp_buffer)-1,"nagfs: just got an unknown state type. Wierd.." );
			temp_buffer[sizeof(temp_buffer)-1]='\x0';
			write_to_all_logs(temp_buffer,NSLOG_INFO_MESSAGE);
		break;
	        }


	//create the directory if it doesn't exist 
	if((dp = opendir(host_path)) == NULL) {
   	if(( mkdir( host_path, S_IRWXU|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH )) != OK){
			snprintf(temp_buffer,sizeof(temp_buffer)-1,"nagfs: Couldn't create the directory: %s",host_path);
			temp_buffer[sizeof(temp_buffer)-1]='\x0';
			write_to_all_logs(temp_buffer,NSLOG_INFO_MESSAGE);
		}
	}else{
		closedir(dp);
	}

   //write the file
   if(( outfile=fopen(host_file,"w")) == NULL){
			snprintf(temp_buffer,sizeof(temp_buffer)-1,"nagfs: Couldn't open file for writing: %s",host_file);
			temp_buffer[sizeof(temp_buffer)-1]='\x0';
			write_to_all_logs(temp_buffer,NSLOG_INFO_MESSAGE);
	}
   fprintf(outfile,"%i",state);
   fclose(outfile);
   return OK;
}

int nagfs_check_for_softfiles(char *soft_file){

	FILE *search_file=NULL;

   if((search_file=fopen(soft_file,"r"))==NULL){
		return OK;
	} else {
		fclose(search_file);
		if((remove(soft_file))!=0){
			return 1;
		}
	}

   return OK;
}