/********************************************
* NetMRG Integrator
*
* monitors.cpp
* NetMRG Gatherer Monitors Library
*
* Copyright (C) 2001-2008
*   Brady Alleman <brady@thtech.net>
*   Douglas E. Warner <silfreed@silfreed.net>
*   Kevin Bonner <keb@nivek.ws>
*
* 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.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*
********************************************/

#include <math.h>
#include <errno.h>
#include <cstring>

#include "monitors.h"

#include "snmp.h"
#include "utils.h"
#include "rrd.h"
#include "locks.h"
#include "events.h"
#include "settings.h"

#ifdef OLD_MYSQL
#define MYSQL_CONNECT(a,b,c,d,e,f,g,h) mysql_connect(a,b,c,d)
#else
#define MYSQL_CONNECT(a,b,c,d,e,f,g,h) mysql_real_connect(a,b,c,d,e,f,g,h)
#endif

#ifdef HAVE_LLROUND
#define ROUND_VAL llround
#else
#define ROUND_VAL (uint)
#endif

string process_internal_monitor(DeviceInfo info, MYSQL *mysql)
{
	string test_result = "U", temp, temp2;
	float disk_total, disk_used;
	unsigned int nCPUs, sum;
	list<SNMPPair> WinCPUList;

	switch(info.test_id)
	{
		// count lines in a file
		case 1:		test_result = count_file_lines(info);
					break;
		
		// TNT "good" modems (that is, available modems - suspect modems)
		case 2:		test_result = snmp_diff(info, ".1.3.6.1.4.1.529.15.1.0", ".1.3.6.1.4.1.529.15.3.0");
					break;
					
		// UCD CPU combined load (user + system)
		case 3:		temp = snmp_get(info, ".1.3.6.1.4.1.2021.11.9.0");
					temp2 = snmp_get(info, ".1.3.6.1.4.1.2021.11.10.0");
					if ( (temp != "U") && (temp2 != "U") )
					{
						test_result = inttostr(strtoint(temp) + strtoint(temp2));
					}
					break;

		// Windows disk usage %
		case 4:
					temp = snmp_get(info, expand_parameters(info, ".1.3.6.1.2.1.25.2.3.1.5.%dskIndex%"));
					disk_total = (float) strtoul(temp.c_str(), NULL, 10);
					temp = snmp_get(info, expand_parameters(info, ".1.3.6.1.2.1.25.2.3.1.6.%dskIndex%"));
					disk_used  = (float) strtoul(temp.c_str(), NULL, 10);
					if (disk_total != 0)
						test_result = inttostr((int) (100*disk_used/disk_total));
					break;

		// UCD Swap utilization %
		case 5:
					temp = snmp_get(info, ".1.3.6.1.4.1.2021.4.3.0");
					disk_total = (float) strtoul(temp.c_str(), NULL, 10);
					temp = snmp_get(info, ".1.3.6.1.4.1.2021.4.4.0");
					disk_used  = (float) strtoul(temp.c_str(), NULL, 10);
					if (disk_total != 0)
						test_result = inttostr((int) (100 - 100*disk_used/disk_total));
					break;
		
		// read value from file
		case 6:		test_result = read_value_from_file(info);
					break;
		
		// report SNMP avoidance status
		case 7:		test_result = inttostr(info.snmp_avoid);
					break;

		// Windows CPU usage %
		case 8:
				WinCPUList = snmp_walk(info, ".1.3.6.1.2.1.25.3.3.1.2"); // hrProcessorLoad

				nCPUs = 0; sum = 0;
				for (list<SNMPPair>::iterator current = WinCPUList.begin();
				     current != WinCPUList.end();
				     current++) {

					nCPUs++;
					sum += strtoul(current->value.c_str(), NULL, 10);
				}
				if (nCPUs > 0) {
					test_result = inttostr(sum / nCPUs);
				} else {
					test_result = "U";
				}
				break;

		default:	debuglogger(DEBUG_MONITOR, LEVEL_WARNING, &info, "Unknown Internal Test (" + inttostr(info.test_id) + ")");
	}

	return test_result;
}

string process_sql_monitor(DeviceInfo info, MYSQL *mysql)
{
	MYSQL		test_mysql;
	MYSQL_RES	*mysql_res, *test_res;
	MYSQL_ROW	mysql_row, test_row;
	string		value = "U";

	string query =
		string("SELECT host, user, password, query, column_num, timeout FROM tests_sql WHERE id = ") + inttostr(info.test_id);
		mysql_res = db_query(mysql, &info, query);

	// if the sql test exists
	if (mysql_res &&
		(mysql_num_rows(mysql_res) == 1) &&
		(mysql_row = mysql_fetch_row(mysql_res)) &&
		(mysql_row[0] != NULL))
	{
		string host = expand_parameters(info, mysql_row[0]);
		string user = expand_parameters(info, mysql_row[1]);
		string password = expand_parameters(info, mysql_row[2]);
		string test_query = expand_parameters(info, mysql_row[3]);
		debuglogger(DEBUG_GATHERER, LEVEL_DEBUG, &info, "MySQL Query Test ({'" +
			host + "'}, {'" + user + "'}, {'" + password + "'}, '" + test_query + "', '" +
			string(mysql_row[4]) + "')");

		netmrg_mutex_lock(lkMySQL);
		mysql_init(&test_mysql);
		uint timeout = strtoint(mysql_row[5]);
		mysql_options(&test_mysql, MYSQL_OPT_CONNECT_TIMEOUT, (const char *) &timeout);

		if (!(MYSQL_CONNECT(&test_mysql,host.c_str(),user.c_str(),password.c_str(), NULL, 0, NULL, 0)))
		{
			netmrg_mutex_unlock(lkMySQL);
			debuglogger(DEBUG_GATHERER, LEVEL_WARNING, &info, "Test MySQL Connection Failure.");
		}
		else
		{
			netmrg_mutex_unlock(lkMySQL);
			if (mysql_query(&test_mysql, test_query.c_str()))
			{
				debuglogger(DEBUG_GATHERER, LEVEL_WARNING, &info, "Test MySQL Query Failed (" + test_query + ")");
			}
			else
			if (!(test_res = mysql_store_result(&test_mysql)))
			{
				debuglogger(DEBUG_GATHERER, LEVEL_WARNING, &info, "Test MySQL Store Result failed.");
			}
			else
			{
				test_row = mysql_fetch_row(test_res);
				if (test_row != NULL)
				{
					if (test_row[strtoint(mysql_row[4])] != NULL)
					{
						value = string(test_row[strtoint(mysql_row[4])]);
					}
					else
					{
						debuglogger(DEBUG_GATHERER, LEVEL_NOTICE, &info, "Selected column is NULL.");
					}
				}
				else
				{
					debuglogger(DEBUG_GATHERER, LEVEL_NOTICE, &info, "There are no rows.");
				}
				mysql_free_result(test_res);
				mysql_close(&test_mysql);
			}
		}
	}
	else
	{
		debuglogger(DEBUG_MONITOR, LEVEL_WARNING, &info, "Unknown SQL Test (" + inttostr(info.test_id) + ").");
	}

	mysql_free_result(mysql_res);
	return value;
}

string process_script_monitor(DeviceInfo info, MYSQL *mysql)
{
	MYSQL_RES	*mysql_res;
	MYSQL_ROW	mysql_row;
	string		value;

	string query =
		string("SELECT cmd, data_type FROM tests_script WHERE id = ") +
		inttostr(info.test_id);
	mysql_res = db_query(mysql, &info, query);

	// if the script test exists
	if (mysql_res &&
		(mysql_num_rows(mysql_res) == 1) &&
		(mysql_row = mysql_fetch_row(mysql_res))
		&& (mysql_row[0] != NULL))
	{
		string command = expand_parameters(info, string(mysql_row[0]));
		if (command[0] != '/')
			command = get_setting(setPathLibexec) + "/" + command;
			
		char **env;
		params_to_env(info, env);

		debuglogger(DEBUG_GATHERER, LEVEL_INFO, &info, "Sending '" + command + "' to shell.");

		pid_t pid;
		char *argv[4];
		argv[0] = "sh";
		argv[1] = "-c";
		argv[2] = (char *) command.c_str();
		argv[3] = NULL;
		
		// if error code is desired
		if (strtoint(mysql_row[1]) == 1)
		{
			int status = 0;
			
			switch (pid = fork())
			{
				case -1:
							// an error occurred during fork()ing
							debuglogger(DEBUG_GATHERER, LEVEL_ERROR, &info, "fork() failed.");
							value = "U";
							break;
				case 0:
							// we're the child
							execve("/bin/sh", argv, env);
							exit(127);	// if we get here, execve() has failed
							break;
				default:
							// we're the parent
							while ( (waitpid(pid, &status, 0) == -1) && (errno == EINTR) );
							if (WIFEXITED(status))
							{
								// the process terminated normally, return the error code
								value = inttostr(WEXITSTATUS(status));
							}
							else
							{
								// the process did not terminate normally, return "unknown"
								debuglogger(DEBUG_MONITOR, LEVEL_NOTICE, &info, "external process terminated abnormally.");
								value = "U";
							}
							break;
			}
		}
		// stdout is desired
		else
		{

			int status = 0;
			int pdes[2];
			volatile int parent_fd, child_fd;
			int perr = 0;

			//netmrg_mutex_lock(lkPipe);
			perr = pipe(pdes);
			//netmrg_mutex_unlock(lkPipe);

			if (perr < 0)
			{
				debuglogger(DEBUG_GATHERER, LEVEL_ERROR, &info, "pipe() failed.");
				value = "U";
			}
			else
			{
				parent_fd = pdes[0];
				child_fd  = pdes[1];
				char buf[256];
				size_t len;

				/*fd_set fds;
				struct timeval timeout;*/

				switch (pid = fork())
				{
					case -1:
								// an error occurred during fork()ing
								close(pdes[0]);
								close(pdes[1]);
								debuglogger(DEBUG_GATHERER, LEVEL_ERROR, &info, "fork() failed.");
								value = "U";
								break;
					case 0:
								// we're the child
								close(parent_fd);
								if (child_fd != STDOUT_FILENO)
								{
									dup2(child_fd, STDOUT_FILENO);
									close(child_fd);
								}
								execve("/bin/sh", argv, env);
								exit(127);	// if we get here, execve() has failed
								break;
					default:
								// we're the parent

								debuglogger(DEBUG_MONITOR, LEVEL_DEBUG, &info, "external process pid is " + inttostr(pid) + ", our fd is " + inttostr(parent_fd));
								close(child_fd);

								/* select() will be useful eventually for limiting the time spent on external progs - but not now 
								FD_ZERO(&fds);
								FD_SET(parent_fd,&fds);
								timeout.tv_sec = 5;
								timeout.tv_usec = 0;

								// wait 5 seonds for pipe response 
								switch(select(parent_fd + 1, &fds, NULL, NULL, &timeout))
								{
									case -1: debuglogger(DEBUG_GATHERER, LEVEL_ERROR, &info, "select() failed."); break;
									case  0: debuglogger(DEBUG_MONITOR, LEVEL_WARNING, &info, "select() timed out."); break;
									default: debuglogger(DEBUG_MONITOR, LEVEL_DEBUG, &info, "select() succeeded."); break;
								}
								*/

								/* move this block to the bottom of read when using select() */
								while ( (waitpid(pid, &status, 0) == -1) && (errno == EINTR) );
								if (!WIFEXITED(status))
								{
									// the process did not terminate normally
									debuglogger(DEBUG_MONITOR, LEVEL_NOTICE, &info, "external process terminated abnormally.");
								}
								else
								{
									debuglogger(DEBUG_MONITOR, LEVEL_DEBUG, &info, "external process terminated normally (" + inttostr(WEXITSTATUS(status)) + ")");
								}

								if ((len = read(parent_fd, (void *) buf, 255)) == -1)
								{
									// error during read
									debuglogger(DEBUG_MONITOR, LEVEL_WARNING, &info, "read() failed.");
									value = "U";
								}
								else
								{
									debuglogger(DEBUG_MONITOR, (len == 0 ? LEVEL_NOTICE : LEVEL_DEBUG), &info, "read() provided " + inttostr(len) + " bytes.");
									buf[len] = '\0';
									value = string(buf);
									if (len == 0) value = "U";
								}
				
								close(parent_fd);

								break;
				}
			}
		}
		free_env(info, env);
	}
	else
	{
		debuglogger(DEBUG_MONITOR, LEVEL_WARNING, &info, "Unknown Script Test (" + inttostr(info.test_id) + ").");
		value = "U";
	}

	mysql_free_result(mysql_res);

	return value;

}

string process_snmp_monitor(DeviceInfo info, MYSQL *mysql)
{
	MYSQL_RES 	*mysql_res;
	MYSQL_ROW 	mysql_row;
	string 		value;

	string query =
		string("SELECT oid, type, subitem FROM tests_snmp WHERE id = ") +
		inttostr(info.test_id);

	mysql_res = db_query(mysql, &info, query);
	
	// if the snmp test exists
	if (mysql_res &&
		(mysql_num_rows(mysql_res) == 1) &&
		(mysql_row = mysql_fetch_row(mysql_res)) &&
		(mysql_row[0] != NULL))
	{
		string oid = expand_parameters(info, mysql_row[0]);
		int type 	= strtoint(mysql_row[1]);
		int subitem = strtoint(mysql_row[2]);

		if (info.snmp_avoid == 0)
		{
			list<SNMPPair> result;
			list<SNMPPair>::iterator x;

			switch (type)
			{
				case 0:
					// plain "get"
					value = snmp_get(info, oid);
					break;

				case 1:
					// walk to Nth item
					result = snmp_walk(info, oid);
					result.reverse();  // sigh, it's upside-down
					x = result.begin();
					for (int k = 0; k < subitem; k++)
					{
						if (x == result.end())
						{
							debuglogger(DEBUG_MONITOR, LEVEL_INFO, &info, "There is no subitem in position " + inttostr(subitem) + ".");
							value = "U";
							break;
						}
						else
						{
							value = x->value;
							x++;
						}
					}
					break;

				case 2:
					// count of walked items
					result = snmp_walk(info, oid);
					value = inttostr(result.size());
					break;

				default:
					value = "U";
					debuglogger(DEBUG_MONITOR, LEVEL_WARNING, &info, "Unknown SNMP Test Type (" + inttostr(type) + ").");
			}
			
		}
		else
		{
			value = "U";
			debuglogger(DEBUG_MONITOR, LEVEL_INFO, &info, "Avoided.");
		}
	}
	else
	{
		value = "U";
		debuglogger(DEBUG_MONITOR, LEVEL_WARNING, &info, "Unknown SNMP Test (" + inttostr(info.test_id) + ").");
	}

	mysql_free_result(mysql_res);

	return value;
}

uint process_monitor(DeviceInfo info, MYSQL *mysql, RRDInfo rrd)
{
	debuglogger(DEBUG_MONITOR, LEVEL_INFO, &info, "Starting Monitor.");

	info.parameters.push_front(ValuePair("parameters", info.test_params));

	switch (info.test_type)
	{
		case  1:	info.curr_val = process_script_monitor(info, mysql);
					break;

		case  2:	info.curr_val = process_snmp_monitor(info, mysql);
					break;

		case  3:	info.curr_val = process_sql_monitor(info, mysql);
					break;

		case  4:	info.curr_val = process_internal_monitor(info, mysql);
					break;

		default:	debuglogger(DEBUG_MONITOR, LEVEL_WARNING, &info, "Unknown test type (" + inttostr(info.test_type) + ").");
					info.curr_val = "U";

	} // end switch

	debuglogger(DEBUG_MONITOR, LEVEL_INFO, &info, "Value: " + strstripnl(info.curr_val));

	// strip out anything not numeric
	info.curr_val = remove_nonnumerics(info.curr_val);
	
	if (rrd.data_type != "")
	{
		update_monitor_rrd(info, rrd);
	}

	// what type of value are we dealing with?
	if (info.curr_val == "U")
	{
		// value is unknown
		debuglogger(DEBUG_MONITOR, LEVEL_INFO, &info, "Value is unknown.");
	}
	else if (info.curr_val == inttostr(strtoint(info.curr_val)))
	{
		// value is an integer
		// (do nothing)
		debuglogger(DEBUG_MONITOR, LEVEL_INFO, &info, "Value is an integer.");
	}
	else if (info.curr_val == "")
	{
		// value is non-numeric
		debuglogger(DEBUG_MONITOR, LEVEL_INFO, &info, "Value is not numeric.");
		info.curr_val = "U";
	}
	else
	{
		//value is probably decimal
		debuglogger(DEBUG_MONITOR, LEVEL_INFO, &info, "Value is a decimal.");
		info.curr_val = inttostr(ROUND_VAL(strtodec(info.curr_val)));
	}

	if ((info.curr_val == "U") || (info.last_val == "U"))
	{
		info.delta_val = "U";
		info.rate_val  = "U";
	}
	else
	{
		info.delta_val = inttostr(strtoint(info.curr_val) - strtoint(info.last_val));
		if (info.delta_time != 0)
		{
			info.rate_val  = inttostr(strtoint(info.delta_val) / info.delta_time);
		}
		else
		{
			info.rate_val  = "U";
		}
	}
	
	// populate parameters
	info.parameters.push_front(ValuePair("current_value", info.curr_val));
	info.parameters.push_front(ValuePair("delta_value", info.delta_val));
	info.parameters.push_front(ValuePair("rate_value", info.rate_val));
	info.parameters.push_front(ValuePair("last_value", info.last_val));

	uint status = process_events(info, mysql);

	info.status = status;
	update_monitor_db(info, mysql, rrd);

	return status;
}

// update_monitor_db
//
// update the database with current values for a monitor

void update_monitor_db(DeviceInfo info, MYSQL *mysql, RRDInfo rrd)
{
	if (info.curr_val == "U")
	{
		info.curr_val = "NULL";
	}

	if (info.delta_val == "U")
	{
		info.delta_val = "NULL";
	}

	db_update(mysql, &info, "UPDATE monitors SET tuned=1, last_val=" + info.curr_val +
		", delta_val=" + info.delta_val +
		", delta_time=UNIX_TIMESTAMP(NOW())-UNIX_TIMESTAMP(last_time), "+
		"last_time=NOW(), status=" + inttostr(info.status) +
		" WHERE id=" + inttostr(info.monitor_id));
}

// expand_parameters
//
// expand parameters within a string

string expand_parameters(DeviceInfo &info, string input)
{
	for (list<ValuePair>::iterator current = info.parameters.begin(); current != info.parameters.end(); current++)
	{
		input = token_replace(input, "%" + current->name + "%", current->value);
	}
	return input;
}

void params_to_env(DeviceInfo &info, char ** &env)
{
	int count = info.parameters.size() + 1;
	env = new char* [count];
	int i = 0;
	for (list<ValuePair>::iterator current = info.parameters.begin(); current != info.parameters.end(); current++)
	{
		string env_string = "netmrg_" + current->name + "=" + current->value;
		env[i] = new char[env_string.length() + 1];
		strncpy(env[i], env_string.c_str(), env_string.length() + 1);
		i++;
	}
	env[count - 1] = NULL;
	
	for (int i = 0; i < count; i++)
		if (env[i] != NULL)
			debuglogger(DEBUG_MONITOR, LEVEL_DEBUG, &info, string("Env: ") + env[i]);
}

void free_env(DeviceInfo &info, char ** &env)
{
	for (int i = 0; i < info.parameters.size() + 1; i++)
		delete [] env[i];
	delete [] env;
}