<?php
/*
 +-------------------------------------------------------------------------+
 | Copyright (C) 2004-2015 The Cacti Group                                 |
 |                                                                         |
 | 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.                            |
 +-------------------------------------------------------------------------+
 | Cacti: The Complete RRDTool-based Graphing Solution                     |
 +-------------------------------------------------------------------------+
 | This code is designed, written, and maintained by the Cacti Group. See  |
 | about.php and/or the AUTHORS file for specific developer information.   |
 +-------------------------------------------------------------------------+
 | http://www.cacti.net/                                                   |
 +-------------------------------------------------------------------------+
*/

/* db_connect_real - makes a connection to the database server
   @param $device - the hostname of the database server, 'localhost' if the database server is running
      on this machine
   @param $user - the username to connect to the database server as
   @param $pass - the password to connect to the database server with
   @param $db_name - the name of the database to connect to
   @param $db_type - the type of database server to connect to, only 'mysql' is currently supported
   @param $retries - the number a time the server should attempt to connect before failing
   @returns - (bool) '1' for success, '0' for error */
function db_connect_real($device, $user, $pass, $db_name, $db_type = 'mysql', $port = '3306', $db_ssl = false, $retries = 20) {
	global $database_sessions;

	$i = 0;
	$error = '';
	if (isset($database_sessions["$device:$port:$db_name"])) {
		return $database_sessions["$device:$port:$db_name"];
	}

	$flags = array();
	if ($db_type == 'mysql') {
		// Using 'localhost' will force unix sockets mode, which breaks when attempting to use mysql on a different port
		if ($device == 'localhost' && $port != '3306') {
			$device = '127.0.0.1';
		}

		$flags[PDO::ATTR_PERSISTENT] =  true;
		$flags[PDO::MYSQL_ATTR_FOUND_ROWS] =  true;
		if ($db_ssl) {
			// PDO requires paths to certificates for SSL support, will have to figure out the best way to handle this
			// I believe they can instead setup these parameters in their mysql config file in [client]
			//$flags[PDO::MYSQL_ATTR_SSL_KEY]  = '/path/to/client-key.pem';
			//$flags[PDO::MYSQL_ATTR_SSL_CERT] = '/path/to/client-cert.pem';
			//$flags[PDO::MYSQL_ATTR_SSL_CA]   = '/path/to/ca-cert.pem';
		}
	}

	while ($i <= $retries) {
		try {
			$cnn_id = new PDO("$db_type:host=$device;port=$port;dbname=$db_name;charset=utf8", $user, $pass, $flags);
			$cnn_id->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_SILENT);
			$database_sessions["$device:$port:$db_name"] = $cnn_id;
			return $cnn_id;
		} catch (PDOException $e) {
			// Must catch this exception or else PDO will display an error with our username/password
			//print $e->getMessage();
			//exit;
		}
		$i++;
		usleep(40000);
	}
	return FALSE;
}

/* db_close - closes the open connection
   @returns - the result of the close command */
function db_close($db_conn = FALSE) {
	global $database_sessions, $database_default, $database_hostname, $database_port;

	/* check for a connection being passed, if not use legacy behavior */
	if (!$db_conn) {
		$db_conn = $database_sessions["$database_hostname:$database_port:$database_default"];
	}

	if (!$db_conn) return FALSE;

	$db_conn = null;
	$database_sessions["$database_hostname:$database_port:$database_default"] = null;

	return TRUE;
}

/* db_execute - run an sql query and do not return any output
   @param $sql - the sql query to execute
   @param $log - whether to log error messages, defaults to true
   @returns - '1' for success, '0' for error */
function db_execute($sql, $log = TRUE, $db_conn = FALSE) {
	return db_execute_prepared($sql, array(), $log, $db_conn);
}

/* db_execute_prepared - run an sql query and do not return any output
   @param $sql - the sql query to execute
   @param $log - whether to log error messages, defaults to true
   @returns - '1' for success, '0' for error */
function db_execute_prepared($sql, $parms = array(), $log = TRUE, $db_conn = FALSE) {
	global $database_sessions, $database_default, $config, $database_hostname, $database_port;

	/* check for a connection being passed, if not use legacy behavior */
	if (!$db_conn) {
		$db_conn = $database_sessions["$database_hostname:$database_port:$database_default"];
	}
	if (!$db_conn) return FALSE;

	$sql = trim(str_replace("\n", '', str_replace("\r", '', str_replace("\t", ' ', $sql))), ';');

	if (read_config_option('log_verbosity') == POLLER_VERBOSITY_DEVDBG) {
		cacti_log('DEVEL: SQL Exec: "' . $sql . '"', FALSE);
	}
	$errors = 0;
	$db_conn->affected_rows = 0;

	while (1) {
		$query = $db_conn->prepare($sql);
		$query->execute($parms);
		if ($query->errorCode()) {
			$errorinfo = $query->errorInfo();
			$en = $errorinfo[1];
		}elseif ($db_conn->errorCode()) {
			$errorinfo = $db_conn->errorInfo();
			$en = $errorinfo[1];
		}else{
			$en = '';
		}

		if ($en == '') {
			// With PDO, we have to free this up
			$db_conn->affected_rows = $query->rowCount();
			$query->closeCursor();
			unset($query);
			return TRUE;
		} else if (($log) || (read_config_option('log_verbosity') >= POLLER_VERBOSITY_DEBUG)) {
			if ($en == 1213 || $en == 1205) { //substr_count(mysql_error($db_conn), 'Deadlock')
				$errors++;
				if ($errors > 30) {
					cacti_log("ERROR: Too many Lock/Deadlock errors occurred! SQL:'" . str_replace("\n", '', str_replace("\r", '', str_replace("\t", ' ', $sql))) . "'", TRUE);
					return FALSE;
				} else {
					usleep(500000);
					continue;
				}
			} else {
				cacti_log("ERROR: A DB Exec Failed!, Error:$en, SQL:\"" . str_replace("\n", '', str_replace("\r", '', str_replace("\t", ' ', $sql))) . "'", FALSE);
				cacti_log('ERROR: A DB Exec Failed!, Error: ' . $errorinfo[2]);
 				$callers = debug_backtrace();
				$s = '';
				foreach ($callers as $c) {
					$file = str_replace($config['base_path'], '', $c['file']);
					$line = $c['line'];
					$func = $c['function'];
					$s = "($file:$line $func)" . $s;
				}
				cacti_log("SQL Backtrace: $s", false);
				return FALSE;
			}
		}
	}
	unset($query);
	return FALSE;
}


/* db_fetch_cell - run a 'select' sql query and return the first column of the
     first row found
   @param $sql - the sql query to execute
   @param $col_name - use this column name instead of the first one
   @param $log - whether to log error messages, defaults to true
   @returns - (bool) the output of the sql query as a single variable */
function db_fetch_cell($sql, $col_name = '', $log = TRUE, $db_conn = FALSE) {
	return db_fetch_cell_prepared($sql, array(), $col_name, $log, $db_conn);
}

/* db_fetch_cell_prepared - run a 'select' sql query and return the first column of the
     first row found
   @param $sql - the sql query to execute
   @param $col_name - use this column name instead of the first one
   @param $log - whether to log error messages, defaults to true
   @returns - (bool) the output of the sql query as a single variable */
function db_fetch_cell_prepared($sql, $parms = array(), $col_name = '', $log = TRUE, $db_conn = FALSE) {
	global $database_sessions, $database_default, $config, $database_hostname, $database_port;

	/* check for a connection being passed, if not use legacy behavior */
	if (!$db_conn) {
		$db_conn = $database_sessions["$database_hostname:$database_port:$database_default"];
	}
	if (!$db_conn) return FALSE;
	$sql = str_replace("\n", '', str_replace("\r", '', str_replace("\t", ' ', $sql)));

	if (read_config_option('log_verbosity') == POLLER_VERBOSITY_DEVDBG) {
		cacti_log('DEVEL: SQL Cell: "' . $sql . '"', FALSE);
	}
	$db_conn->affected_rows = 0;
	$query = $db_conn->prepare($sql);
	$query->execute($parms);
	$errorinfo = $query->errorInfo();
	$en = $errorinfo[1];
	if ($en == '') {
		$db_conn->affected_rows = $query->rowCount();
		$q = $query->fetchAll(PDO::FETCH_BOTH);
		$query->closeCursor();
		unset($query);
		if (isset($q[0]) && is_array($q[0])) {
			if ($col_name != '') {
				return $q[0][$col_name];
			} else {
				return reset($q[0]);
			}
		}
		return FALSE;
	}else if (($log) || (read_config_option('log_verbosity') >= POLLER_VERBOSITY_DEBUG)) {
		cacti_log("ERROR: SQL Cell Failed!, Error:$en, SQL:\"" . str_replace("\n", '', str_replace("\r", '', str_replace("\t", ' ', $sql))) . '"', FALSE);
		cacti_log('ERROR: SQL Cell Failed!, Error: ' . $errorinfo[2]);
		$callers = debug_backtrace();
		$s = '';
		foreach ($callers as $c) {
			$file = str_replace($config['base_path'], '', $c['file']);
			$line = $c['line'];
			$func = $c['function'];
			$s = "($file:$line $func)" . $s;
		}
		cacti_log("SQL Backtrace: $s", false);
	}
	if (isset($query)) unset($query);
	return FALSE;
}

/* db_fetch_row - run a 'select' sql query and return the first row found
   @param $sql - the sql query to execute
   @param $log - whether to log error messages, defaults to true
   @returns - the first row of the result as a hash */
function db_fetch_row($sql, $log = TRUE, $db_conn = FALSE) {
	return db_fetch_row_prepared($sql, array(), $log, $db_conn);
}

/* db_fetch_row_prepared - run a 'select' sql query and return the first row found
   @param $sql - the sql query to execute
   @param $log - whether to log error messages, defaults to true
   @returns - the first row of the result as a hash */
function db_fetch_row_prepared($sql, $parms = array(), $log = TRUE, $db_conn = FALSE) {
	global $database_sessions, $database_default, $config, $database_hostname, $database_port;

	/* check for a connection being passed, if not use legacy behavior */
	if (!$db_conn) {
		$db_conn = $database_sessions["$database_hostname:$database_port:$database_default"];
	}
	if (!$db_conn) return FALSE;

	$sql = str_replace("\n", '', str_replace("\r", '', str_replace("\t", ' ', $sql)));

	if (($log) && (read_config_option('log_verbosity') == POLLER_VERBOSITY_DEVDBG)) {
		cacti_log('DEVEL: SQL Row: "' . $sql . '"', FALSE);
	}
	$db_conn->affected_rows = 0;
	$query = $db_conn->prepare($sql);
	$query->execute($parms);
	$errorinfo = $query->errorInfo();
	$en = $errorinfo[1];
	if ($en == '') {
		$db_conn->affected_rows = $query->rowCount();
		$q = $query->fetchAll(PDO::FETCH_ASSOC);
		$query->closeCursor();
		unset($query);
		if (isset($q[0])) {
			return $q[0];
		} else {
			return array();
		}
	}else if (($log) || (read_config_option('log_verbosity') >= POLLER_VERBOSITY_DEBUG)) {
		cacti_log("ERROR: SQL Row Failed!, Error:$en, SQL:\"" . str_replace("\n", '', str_replace("\r", '', str_replace("\t", ' ', $sql))) . '"', FALSE);
		cacti_log('ERROR: SQL Row Failed!, Error: ' . $errorinfo[2]);
		$callers = debug_backtrace();
		$s = '';
		foreach ($callers as $c) {
			$file = str_replace($config['base_path'], '', $c['file']);
			$line = $c['line'];
			$func = $c['function'];
			$s = "($file:$line $func)" . $s;
		}
		cacti_log("SQL Backtrace: $s", false);

	}
	if (isset($query)) unset($query);
	return array();
}

/* db_fetch_assoc - run a 'select' sql query and return all rows found
   @param $sql - the sql query to execute
   @param $log - whether to log error messages, defaults to true
   @returns - the entire result set as a multi-dimensional hash */
function db_fetch_assoc($sql, $log = TRUE, $db_conn = FALSE) {
	return db_fetch_assoc_prepared($sql, array(), $log, $db_conn);
}

/* db_fetch_assoc_prepared - run a 'select' sql query and return all rows found
   @param $sql - the sql query to execute
   @param $log - whether to log error messages, defaults to true
   @returns - the entire result set as a multi-dimensional hash */
function db_fetch_assoc_prepared($sql, $parms = array(), $log = TRUE, $db_conn = FALSE) {
	global $database_sessions, $database_default, $config, $database_hostname, $database_port;

	/* check for a connection being passed, if not use legacy behavior */
	if (!$db_conn) {
		$db_conn = $database_sessions["$database_hostname:$database_port:$database_default"];
	}
	if (!$db_conn) return FALSE;

	$sql = str_replace("\n", '', str_replace("\r", '', str_replace("\t", ' ', $sql)));

	if (read_config_option('log_verbosity') == POLLER_VERBOSITY_DEVDBG) {
		cacti_log('DEVEL: SQL Assoc: "' . $sql . '"', FALSE);
	}
	$db_conn->affected_rows = 0;
	$query = $db_conn->prepare($sql);
	$query->execute($parms);
	$errorinfo = $query->errorInfo();
	$en = $errorinfo[1];
	if ($en == '') {
		$db_conn->affected_rows = $query->rowCount();
		$a = $query->fetchAll(PDO::FETCH_ASSOC);
		$query->closeCursor();
		unset($query);
		if (!is_array($a)) {
			$a = array();
		}
		return $a;
	}else if (($log) || (read_config_option('log_verbosity') >= POLLER_VERBOSITY_DEBUG)) {
		cacti_log("ERROR: SQL Assoc Failed!, Error:$en, SQL:\"" . str_replace("\n", '', str_replace("\r", '', str_replace("\t", ' ', $sql))) . '"');
		cacti_log('ERROR: SQL Assoc Failed!, Error: ' . $errorinfo[2]);
		$callers = debug_backtrace();
		$s = '';
		foreach ($callers as $c) {
			$file = str_replace($config['base_path'], '', $c['file']);
			$line = $c['line'];
			$func = $c['function'];
			$s = "($file:$line $func)" . $s;
		}
		cacti_log("SQL Backtrace: $s", false);
	}
	if (isset($query)) unset($query);
	return array();
}

/* db_fetch_insert_id - get the last insert_id or auto incriment
   @returns - the id of the last auto incriment row that was created */
function db_fetch_insert_id($db_conn = FALSE) {
	global $database_sessions, $database_default, $database_hostname, $database_port;

	/* check for a connection being passed, if not use legacy behavior */
	if (!$db_conn) {
		$db_conn = $database_sessions["$database_hostname:$database_port:$database_default"];
	}
	if ($db_conn) {
		return $db_conn->lastInsertId();
	}
	return FALSE;
}

/* db_affected_rows - return the number of rows affected by the last transaction
 * @returns - the number of rows affected by the last transaction */
function db_affected_rows($db_conn = FALSE) {
	global $database_sessions, $database_default, $database_hostname, $database_port;

	/* check for a connection being passed, if not use legacy behavior */
	if (!$db_conn) {
		$db_conn = $database_sessions["$database_hostname:$database_port:$database_default"];
	}
	if (!$db_conn) return FALSE;
	return $db_conn->affected_rows;
}

/* db_add_column - add a column to table
   @param $table - the name of the table
   @param $column - array of column data ex: array('name' => 'test' . rand(1, 200), 'type' => 'varchar (255)', 'NULL' => false)
   @param $log - whether to log error messages, defaults to true
   @returns - '1' for success, '0' for error */
function db_add_column ($table, $column, $log = TRUE, $db_conn = FALSE) {
	global $database_sessions, $database_default, $database_hostname, $database_port;

	/* check for a connection being passed, if not use legacy behavior */
	if (!$db_conn) {
		$db_conn = $database_sessions["$database_hostname:$database_port:$database_default"];
	}
	if (!$db_conn) return FALSE;

	$result = db_fetch_assoc('SHOW columns FROM `' . $table . '`', $log, $db_conn);
	$columns = array();
	foreach($result as $arr) {
		$columns[] = $t['Field'];
	}
	if (isset($column['name']) && !in_array($column['name'], $columns)) {
		$sql = 'ALTER TABLE `' . $table . '` ADD `' . $column['name'] . '`';
		if (isset($column['type']))
			$sql .= ' ' . $column['type'];
		if (isset($column['unsigned']))
			$sql .= ' unsigned';
		if (isset($column['NULL']) && $column['NULL'] == false)
			$sql .= ' NOT NULL';
		if (isset($column['NULL']) && $column['NULL'] == true && !isset($column['default']))
			$sql .= ' default NULL';
		if (isset($column['default']))
			$sql .= ' default ' . (is_numeric($column['default']) ? $column['default'] : "'" . $column['default'] . "'");
		if (isset($column['auto_increment']))
			$sql .= ' auto_increment';
		if (isset($column['after']))
			$sql .= ' AFTER ' . $column['after'];
		return db_execute($sql, $log, $db_conn);
	}
	return true;
}

/* db_remove_column - remove a column to table
   @param $table - the name of the table
   @param $column - column name
   @param $log - whether to log error messages, defaults to true
   @returns - '1' for success, '0' for error */
function db_remove_column ($table, $column, $log = TRUE, $db_conn = FALSE) {
	global $database_sessions, $database_default, $database_hostname, $database_port;

	/* check for a connection being passed, if not use legacy behavior */
	if (!$db_conn) {
		$db_conn = $database_sessions["$database_hostname:$database_port:$database_default"];
	}
	if (!$db_conn) return FALSE;

	$result = db_fetch_assoc('SHOW columns FROM `' . $table . '`', $log, $db_conn);
	$columns = array();
	foreach($result as $arr) {
		$columns[] = $arr['Field'];
	}
	if (isset($column) && in_array($column, $columns)) {
		$sql = 'ALTER TABLE `' . $table . '` DROP `' . $column . '`';
		return db_execute($sql, $log, $db_conn);
	}
	return true;
}

/* db_table_exists - checks whether a table exists
   @param $table - the name of the table
   @param $log - whether to log error messages, defaults to true
   @returns - (bool) the output of the sql query as a single variable */
function db_table_exists($table, $log = TRUE, $db_conn = FALSE) {
	return (db_fetch_cell("SHOW TABLES LIKE '$table'", '', $log, $db_conn) ? true : false);
}

/* db_column_exists - checks whether a column exists
   @param $table - the name of the table
   @param $log - whether to log error messages, defaults to true
   @returns - (bool) the output of the sql query as a single variable */
function db_column_exists($table, $column, $log = TRUE, $db_conn = FALSE) {
	return (db_fetch_cell("SHOW columns FROM `$table` LIKE '$column'", '', $log, $db_conn) ? true : false);
}


function db_update_table ($table, $data, $removecolumns = FALSE, $log = TRUE, $db_conn = FALSE) {
	global $database_sessions, $database_default, $database_hostname, $database_port;

	/* check for a connection being passed, if not use legacy behavior */
	if (!$db_conn) {
		$db_conn = $database_sessions["$database_hostname:$database_port:$database_default"];
	}
	if (!$db_conn) return FALSE;

	if (!db_table_exists($table, $log, $db_conn)) {
		return db_table_create ($table, $data, $log, $db_conn);
	}

	$allcolumns = array();
	foreach ($data['columns'] as $column) {
		$allcolumns[] = $column['name'];
		if (!db_column_exists($table, $column['name'], $log, $db_conn)) {
			db_add_column ($table, $column, $log, $db_conn);
		} else {
			// Check that column is correct and fix it
			// FIXME: Need to still check default value
			$arr = db_fetch_row("SHOW columns FROM `$table` LIKE '" . $column['name'] . "'", $log, $db_conn);
			if ($column['type'] != $arr['Type'] || (isset($column['NULL']) && ($column['NULL'] ? 'YES' : 'NO') != $arr['Null']) 
							    || (isset($column['auto_increment']) && ($column['auto_increment'] ? 'auto_increment' : '') != $arr['Extra'])) {
				$sql = 'ALTER TABLE `' . $table . '` CHANGE `' . $column['name'] . '` `' . $column['name'] . '`';
				if (isset($column['type']))
					$sql .= ' ' . $column['type'];
				if (isset($column['unsigned']))
					$sql .= ' unsigned';
				if (isset($column['NULL']) && $column['NULL'] == false)
					$sql .= ' NOT NULL';
				if (isset($column['NULL']) && $column['NULL'] == true && !isset($column['default']))
					$sql .= ' default NULL';
				if (isset($column['default']))
					$sql .= ' default ' . (is_numeric($column['default']) ? $column['default'] : "'" . $column['default'] . "'");
				if (isset($column['auto_increment']))
					$sql .= ' auto_increment';
				db_execute($sql, $log, $db_conn);
			}
		}
	}

	if ($removecolumns) {
		$result = db_fetch_assoc('SHOW columns FROM `' . $table . '`', $log, $db_conn);
		foreach($result as $arr) {
			if (!in_array($arr['Field'], $allcolumns)) {
				db_remove_column ($table, $arr['Field'], $log, $db_conn);
			}
		}
	}

	$info = db_fetch_row("SELECT ENGINE, TABLE_COMMENT FROM information_schema.TABLES WHERE TABLE_NAME = '$table'");
	if (isset($info['TABLE_COMMENT']) && str_replace("'", '', $info['TABLE_COMMENT']) != str_replace("'", '', $data['comment'])) {
		db_execute("ALTER TABLE `$table` COMMENT '" . str_replace("'", '', $data['comment']) . "'");
	}

	if (isset($info['ENGINE']) && strtolower($info['ENGINE']) != strtolower($data['type'])) {
		db_execute("ALTER TABLE `$table` ENGINE = " . $data['type']);
	}

	// Correct any indexes
	$indexes = db_fetch_assoc("SHOW INDEX FROM `$table`");
	$allindexes = array();

	foreach ($indexes as $index) {
		$allindexes[$index['Key_name']][$index['Seq_in_index']-1] = $index['Column_name'];
	}

	foreach ($allindexes as $n => $index) {
		if ($n != 'PRIMARY' && isset($data['keys'])) {
			$removeindex = TRUE;
			foreach ($data['keys'] as $k) {
				if ($k['name'] == $n) {
					$removeindex = FALSE;
					$add = array_diff($k['columns'], $index);
					$del = array_diff($index, $k['columns']);
					if (!empty($add) || !empty($del)) {
						db_execute("ALTER TABLE `$table` DROP INDEX `$n`", $log, $db_conn);
						db_execute("ALTER TABLE `$table` ADD INDEX `$n` (`" . (is_array($k['columns']) ? implode('`,`', $k['columns']) : $k['columns']) . '`)', $log, $db_conn);
					}
					break;
				}
			}
			if ($removeindex) {
				db_execute("ALTER TABLE `$table` DROP INDEX `$n`", $log, $db_conn);
			}
		}
	}

	// Add any indexes
	if (isset($data['keys'])) {
		foreach ($data['keys'] as $k) {
			if (!isset($allindexes[$k['name']])) {
				db_execute("ALTER TABLE `$table` ADD INDEX `" . $k['name'] . '` (`' . (is_array($k['columns']) ? implode('`,`', $k['columns']) : $k['columns']) . '`)', $log, $db_conn);
			}
		}
	}

	// FIXME: It won't allow us to drop a primary key that is set to auto_increment

	// Check Primary Key
	if (!isset($data['primary']) && isset($allindexes['PRIMARY'])) {
		db_execute("ALTER TABLE `$table` DROP PRIMARY KEY", $log, $db_conn);
		unset($allindexes['PRIMARY']);
	}

	if (isset($data['primary'])) {
		if (!isset($allindexes['PRIMARY'])) {
			// No current primary key, so add it
			db_execute("ALTER TABLE `$table` ADD PRIMARY KEY(" . $data['primary'] . ")", $log, $db_conn);
		} else {
			$add = array_diff($data['primary'], $allindexes['PRIMARY']);
			$del = array_diff($allindexes['PRIMARY'], $data['primary']);
			if (!empty($add) || !empty($del)) {
				db_execute("ALTER TABLE `$table` DROP PRIMARY KEY", $log, $db_conn);
				db_execute("ALTER TABLE `$table` ADD PRIMARY KEY(`" . (is_array($data['primary']) ? implode('`,`', $data['primary']) : $data['primary']) . "`)", $log, $db_conn);
			}
		}
	}

	return TRUE;
}


/* db_table_create - checks whether a table exists
   @param $table - the name of the table
   @param $data - data array
   @param $log - whether to log error messages, defaults to true
   @returns - (bool) the output of the sql query as a single variable */
function db_table_create ($table, $data, $log = TRUE, $db_conn = FALSE) {
	global $database_sessions, $database_default, $database_hostname, $database_port;

	/* check for a connection being passed, if not use legacy behavior */
	if (!$db_conn) {
		$db_conn = $database_sessions["$database_hostname:$database_port:$database_default"];
	}
	if (!$db_conn) return FALSE;

	if (!db_table_exists($table, $log, $db_conn)) {
		$c = 0;
		$sql = 'CREATE TABLE `' . $table . "` (\n";
		foreach ($data['columns'] as $column) {
			if (isset($column['name'])) {
				if ($c > 0)
					$sql .= ",\n";
				$sql .= '`' . $column['name'] . '`';
				if (isset($column['type']))
					$sql .= ' ' . $column['type'];
				if (isset($column['unsigned']))
					$sql .= ' unsigned';
				if (isset($column['NULL']) && $column['NULL'] == false)
					$sql .= ' NOT NULL';
				if (isset($column['NULL']) && $column['NULL'] == true && !isset($column['default']))
					$sql .= ' default NULL';
				if (isset($column['default']))
					$sql .= ' default ' . (is_numeric($column['default']) ? $column['default'] : "'" . $column['default'] . "'");
				if (isset($column['auto_increment']))
					$sql .= ' auto_increment';
				$c++;
			}
		}

		if (isset($data['primary'])) {
			if (is_array($data['primary'])) {
				$sql .= ",\n PRIMARY KEY (`" . implode('`,`'. $data['primary']) . '`)';
			} else {
				$sql .= ",\n PRIMARY KEY (`" . $data['primary'] . '`)';
			}
		}

		if (isset($data['keys']) && sizeof($data['keys'])) {
		foreach ($data['keys'] as $key) {
			if (isset($key['name'])) {
				if (is_array($key['columns'])) {
					$sql .= ",\n KEY `" . $key['name'] . '` (`' . implode('`,`', $key['columns']) . '`)';
				} else {
					$sql .= ",\n KEY `" . $key['name'] . '` (`' . $key['columns'] . '`)';
				}
			}
		}
		}
		$sql .= ') ENGINE = ' . $data['type'];

		if (isset($data['comment'])) {
			$sql .= " COMMENT = '" . $data['comment'] . "'";
		}
		if (db_execute($sql, $log, $db_conn)) {
			return true;
		}
		return false;
	}
}


/* array_to_sql_or - loops through a single dimentional array and converts each
     item to a string that can be used in the OR portion of an sql query in the
     following form:
        column=item1 OR column=item2 OR column=item2 ...
   @param $array - the array to convert
   @param $sql_column - the column to set each item in the array equal to
   @returns - a string that can be placed in a SQL OR statement */
function array_to_sql_or($array, $sql_column) {
	/* if the last item is null; pop it off */
	if (end($array) === NULL) {
		array_pop($array);
	}

	if (sizeof($array)) {
		$sql_or = "($sql_column IN('" . implode("','", $array) . "'))";

		return $sql_or;
	}
}

/* db_replace - replaces the data contained in a particular row
   @param $table_name - the name of the table to make the replacement in
   @param $array_items - an array containing each column -> value mapping in the row
   @param $keyCols - a string or array of primary keys
   @param $autoQuote - whether to use intelligent quoting or not
   @returns - the auto incriment id column (if applicable) */
function db_replace($table_name, $array_items, $keyCols, $db_conn = FALSE) {
	global $database_sessions, $database_default, $database_hostname, $database_port;

	/* check for a connection being passed, if not use legacy behavior */
	if (!$db_conn) {
		$db_conn = $database_sessions["$database_hostname:$database_port:$database_default"];
	}

	if (read_config_option('log_verbosity') == POLLER_VERBOSITY_DEVDBG) {
		cacti_log("DEVEL: SQL Replace on table '$table_name': \"" . serialize($array_items) . '"', FALSE);
	}

	_db_replace($db_conn, $table_name, $array_items, $keyCols);
	return db_fetch_insert_id($db_conn);
}


// FIXME:  Need to Rename and cleanup a bit

function _db_replace($db_conn, $table, $fieldArray, $keyCols, $has_autoinc) {
	if (!is_array($keyCols)) {
		$keyCols = array($keyCols);
	}

	$sql  = "INSERT INTO `$table` (";
	$sql2 = '';
	$sql3 = '';

	$first  = true;
	$first3 = true;
	foreach($fieldArray as $k => $v) {
		if (!$first) {
			$sql  .= ', ';
			$sql2 .= ', ';
		}
		$sql   .= "`$k`";
		$sql2  .= $v;
		$first  = false;

		if (in_array($k, $keyCols)) continue; // skip UPDATE if is key

		if (!$first3) {
			$sql3 .= ', ';
		}

		$sql3 .= "`$k`=VALUES(`$k`)";

		$first3 = false;
	}

	$sql .= ") VALUES ($sql2)" . ($sql3 != '' ? " ON DUPLICATE KEY UPDATE $sql3" : '');

	@db_execute($sql);

	return db_fetch_insert_id();
}

/* sql_save - saves data to an sql table
   @param $array_items - an array containing each column -> value mapping in the row
   @param $table_name - the name of the table to make the replacement in
   @param $key_cols - the primary key(s)
   @returns - the auto incriment id column (if applicable) */
function sql_save($array_items, $table_name, $key_cols = 'id', $autoinc = TRUE, $db_conn = FALSE) {
	global $database_sessions, $database_default, $database_hostname, $database_port;

	/* check for a connection being passed, if not use legacy behavior */
	if (!$db_conn) {
		$db_conn = $database_sessions["$database_hostname:$database_port:$database_default"];
	}

	if (read_config_option('log_verbosity') == POLLER_VERBOSITY_DEVDBG) {
		cacti_log("DEVEL: SQL Save on table '$table_name': \"" . serialize($array_items) . '"', FALSE);
	}

	while (list($key, $value) = each($array_items)) {
		$array_items[$key] = '"' . sql_sanitize($value) . '"';
	}

	$replace_result = _db_replace($db_conn, $table_name, $array_items, $key_cols, $autoinc);

	if ($replace_result === false) {
		cacti_log("ERROR: SQL Save Command Failed for Table '$table_name'.  Error was '" . mysql_error($db_conn) . "'", false);
		return FALSE;
	}

	/* get the last AUTO_ID and return it */
	if (!$replace_result || db_fetch_insert_id($db_conn) == '0') {
		if (!is_array($key_cols)) {
			if (isset($array_items[$key_cols])) {
				return str_replace('"', '', $array_items[$key_cols]);
			}
		}
		return FALSE;
	} else {
		return $replace_result;
	}
}

/* sql_sanitize - removes and quotes unwanted chars in values passed for use in SQL statements
   @param $value - value to sanitize
   @return - fixed value */
function sql_sanitize($value) {
	//$value = str_replace("'", "''", $value);
	$value = str_replace(';', "\;", $value);

	return $value;
}

/* sql_column_exists - checks if a named column exists in the table specified
   @param $table_name - table to check
   @param $column_name - column name
   @return true or false; */
function sql_column_exists($table_name, $column_name, $db_conn = '') {
	global $database_sessions, $database_default, $database_hostname, $database_port;

	/* check for a connection being passed, if not use legacy behavior */
	if (!$db_conn) {
		$db_conn = $database_sessions["$database_hostname:$database_port:$database_default"];
	}

	$columns = db_fetch_assoc("SHOW COLUMNS FROM `$table_name`", false);

	foreach ($columns as $column) {
		if ($column_name === $column['name']) {
			return true;
		}
	}

	return false;
}

/* sql_function_timestamp - abstracts timestamp function across databases
   @return - fixed value */
function sql_function_timestamp($db_conn = '') {
	global $database_sessions, $database_default, $database_hostname, $database_port;

	/* check for a connection being passed, if not use legacy behavior */
	if (!$db_conn) {
		$db_conn = $database_sessions["$database_hostname:$database_port:$database_default"];
	}

	return 'NOW()';

	//if (isset($db_conn->sysTimeStamp)) {
	//	return $db_conn->sysTimeStamp;
	//}

	//return "'".date('Y-m-d H:i:s')."'";
}

/* sql_function_substr - abstracts substring function across databases
   @return - fixed value */
function sql_function_substr($db_conn = '') {
	global $database_sessions, $database_default, $database_hostname, $database_port;

	/* check for a connection being passed, if not use legacy behavior */
	if (!$db_conn) {
		$db_conn = $database_sessions["$database_hostname:$database_port:$database_default"];
	}

	return 'substring';

//	if (isset($db_conn->substr)) {
//		return $db_conn->substr;
//	}

//	switch($db_conn->databaseType) {
//		case 'oci805':
//		case 'oci8':
//		case 'oci8po':
//		case 'oracle':
//			return 'substr';
//			break;
//		case 'postgres64':
//		case 'postgres7':
//		case 'postgres':
//			return 'substr';
//			break;
//		case 'db2':
//		case 'fbsql':
//		case 'firebird':
//		case 'ibase':
//			default:
//			return 'substr';
//	}
}

/* sql_function_concat - abstracts concatenation function across databases
   @return - fixed value */
function sql_function_concat($db_conn = '') {
	global $database_sessions, $database_default, $database_hostname, $database_port;

	/* check for a connection being passed, if not use legacy behavior */
	if (!$db_conn) {
		$db_conn = $database_sessions["$database_hostname:$database_port:$database_default"];
	}

	//if (method_exists($db_conn, 'Concat')) {
	//	$args = func_get_args();
	//	return call_user_func_array(array(&$db_conn, 'Concat'), $args);
	//}

	return "concat('".implode("','", func_get_args())."')";
}

/* sql_function_replace - abstracts replace function across databases
   @return - fixed value */
function sql_function_replace($db_conn = '') {
	global $database_sessions, $database_default, $database_hostname, $database_port;

	/* check for a connection being passed, if not use legacy behavior */
	if (!$db_conn) {
		$db_conn = $database_sessions["$database_hostname:$database_port:$database_default"];
	}

	return 'replace';

//	switch($db_conn->databaseType) {
//		case 'mssql':
//		case 'mssqlpo':
//			return 'replace';
//			break;
//		case 'mysql':
//		case 'mysqli':
//		case 'mysqlt':
//			return 'replace';
//			break;
//		case 'oci805':
//		case 'oci8':
//		case 'oci8po':
//		case 'oracle':
//			return 'replace';
//			break;
//		case 'postgres64':
//		case 'postgres7':
//		case 'postgres':
//			return 'replace';
//			break;
//		case 'db2':
//		case 'firebird':
//		case 'ibase':
//		default:
//			return 'replace';
//	}
}

/* sql_function_dateformat - abstracts dateformat function across databases
   @return - fixed value */
function sql_function_dateformat($fmt, $col = false, $db_conn = '') {
	global $database_sessions, $database_default, $database_hostname, $database_port;

	/* check for a connection being passed, if not use legacy behavior */
	if (!$db_conn) {
		$db_conn = $database_sessions["$database_hostname:$database_port:$database_default"];
	}

	return 'date_format';

//	if (method_exists($db_conn, 'SQLDate')) {
//		return call_user_func_array(array(&$db_conn, 'SQLDate'), array($fmt,$col));
//	}
//
//	switch($db_conn->databaseType) {
//		default:
//			return 'date_format';
//	}
}

function db_qstr($s, $db_conn = '') {
	global $database_sessions, $database_default, $database_hostname, $database_port;

	/* check for a connection being passed, if not use legacy behavior */
	if (!$db_conn) {
		$db_conn = $database_sessions["$database_hostname:$database_port:$database_default"];
	}

	$replaceQuote = "\\'";

	if (is_null($s)) return 'NULL';

	if (is_resource($db_conn))
		return $db_conn->quote($s);
	if ($replaceQuote == '\\') {
		$s = str_replace(array('\\', "\0"), array('\\\\', "\\\0"), $s);
	}
	return  "'" . str_replace("'",$replaceQuote, $s) . "'";
}