<?php
	/**
	 * - DB child class
	 * - Cubrid DBMS to use the class
	 * - Works with CUBRID up to 8.4.1
	 *
	 * @author NHN (developers@xpressengine.com)
	 * @package /classes/db
	 * @version 0.1
	 */
	class DBCubrid extends DB
	{

		/**
		 * prefix of XE tables(One more XE can be installed on a single DB)
		 * @var string
		 */
		var $prefix = 'xe_';
		/**
		 * max size of constant in CUBRID(if string is larger than this, '...'+'...' should be used)
		 * @var int
		 */
		var $cutlen = 12000;
		var $comment_syntax = '/* %s */';

		/**
		 * column type used in CUBRID
		 *
		 * column_type should be replaced for each DBMS's type
		 * becasue it uses commonly defined type in the schema/query xml
		 * @var array
		 **/
		var $column_type = array(
			'bignumber' => 'numeric(20)',
			'number' => 'integer',
			'varchar' => 'character varying',
			'char' => 'character',
			'tinytext' => 'character varying(256)',
			'text' => 'character varying(1073741823)',
			'bigtext' => 'character varying(1073741823)',
			'date' => 'character varying(14)',
			'float' => 'float',
		);

		/**
		 * constructor
		 * @return void
		 */
		function DBCubrid()
		{
			$this->_setDBInfo();
			$this->_connect();
		}

		/**
		 * Create an instance of this class
		 * @return DBCubrid return DBCubrid object instance
		 */
		function create()
		{
			return new DBCubrid;
		}

		/**
		 * Return if supportable
		 * Check 'cubrid_connect' function exists.
		 * @return boolean
		 */
		function isSupported()
		{
			if (!function_exists('cubrid_connect')) return FALSE;
			return TRUE;
		}

		/**
		 * DB Connect
		 * this method is private
		 * @param array $connection connection's value is db_hostname, db_port, db_database, db_userid, db_password
		 * @return resource
		 */
		function __connect($connection)
		{
            // attempts to connect
			$result = @cubrid_connect($connection["db_hostname"], $connection["db_port"], $connection["db_database"], $connection["db_userid"], $connection["db_password"]);

			// check connections
			if (!$result) {
				$this->setError (-1, 'database connect fail');
				return;
			}
			
			if(!defined('__CUBRID_VERSION__')) {
				$cubrid_version = cubrid_get_server_info($result);
				$cubrid_version_elem = explode('.', $cubrid_version);
				$cubrid_version = $cubrid_version_elem[0] . '.' . $cubrid_version_elem[1] . '.' . $cubrid_version_elem[2];
				define('__CUBRID_VERSION__', $cubrid_version);
			}
			
			if(__CUBRID_VERSION__ >= '8.4.0')
				cubrid_set_autocommit($result, CUBRID_AUTOCOMMIT_TRUE);			
            
			return $result;
		}

		/**
		 * DB disconnection
		 * this method is private
		 * @param resource $connection
		 * @return void
		 */
		function _close($connection)
		{
			@cubrid_commit ($connection);
			@cubrid_disconnect ($connection);
			$this->transaction_started = FALSE;
		}

		/**
		 * Handles quatation of the string variables from the query
		 * @param string $string
		 * @return string
		 */
		function addQuotes($string)
		{
			if (version_compare (PHP_VERSION, "5.9.0", "<") &&
			  get_magic_quotes_gpc ()) {
				$string = stripslashes (str_replace ("\\","\\\\", $string));
			}

			if (!is_numeric ($string)) {
			/*
				if ($this->isConnected()) {
					$string = cubrid_real_escape_string($string);
				}
				else {
					$string = str_replace("'","\'",$string);
				}
				*/

				$string = str_replace("'","''",$string);
			}

			return $string;
		}

		/**
		 * DB transaction start
		 * this method is private
		 * @return boolean
		 */
		function _begin()
		{
			if(__CUBRID_VERSION__ >= '8.4.0')
			{
				$connection = $this->_getConnection('master');
				cubrid_set_autocommit($connection, CUBRID_AUTOCOMMIT_FALSE);						
			}
			return TRUE;
		}

		/**
		 * DB transaction rollback
		 * this method is private
		 * @return boolean
		 */
		function _rollback()
		{
            $connection = $this->_getConnection('master');
			@cubrid_rollback ($connection);
            return TRUE;
		}

		/**
		 * DB transaction commit
		 * this method is private
		 * @return boolean
		 */
		function _commit()
		{
			$connection = $this->_getConnection('master');
			@cubrid_commit($connection);
			return TRUE;
		}

		/**
		 * Execute the query
		 * this method is private
		 * @param string $query
		 * @param resource $connection
		 * @return resource
		 */
		function __query($query, $connection)
		{
			if($this->use_prepared_statements == 'Y')
			{
				$req = @cubrid_prepare($connection, $query);
				if(!$req)
				{
					$this->_setError();
					return false;
				}

				$position = 0;
				if($this->param)
				{
					foreach($this->param as $param)
					{
						$value = $param->getUnescapedValue();
						$type = $param->getType();
						
						if($param->isColumnName()) continue;

						switch($type)
							{
								case 'number' : 
												$bind_type = 'numeric'; 
												break;
								case 'varchar' : 
												$bind_type = 'string'; 
												break;
								default: 
												$bind_type = 'string';
							}		

						if(is_array($value)){
							foreach($value as $v)
							{
								$bound = @cubrid_bind($req, ++$position, $v, $bind_type);
								if(!$bound)
								{
									$this->_setError();
									return false;
								}
							}
						}
						else
						{
							$bound = @cubrid_bind($req, ++$position, $value, $bind_type);
							if(!$bound)
							{
								$this->_setError();
								return false;
							}
						}
					}
				}
				
				$result = @cubrid_execute($req);
				if(!$result)
				{
					$this->_setError();
					return false;
				}
				return $req;
				
			}
			// Execute the query
			$result = @cubrid_execute ($connection, $query);
			// error check
			if (!$result) {
				$this->_setError();
				return false;
			}
			// Return the result
 			return $result;
		}

		/**
		 * Retrieve CUBRID error and set to object
		 *
		 * @author Corina Udrescu (dev@xpressengine.org)
		 */
		function _setError()
		{
			$code = cubrid_error_code ();
			$msg = cubrid_error_msg ();

			$this->setError ($code, $msg);
		}

		/**
		 * Fetch the result
		 * @param resource $result
		 * @param int|NULL $arrayIndexEndValue
		 * @return array
		 */
		function _fetch($result, $arrayIndexEndValue = NULL)
		{
			$output = array();
			if (!$this->isConnected() || $this->isError() || !$result) return array();

			if($this->use_prepared_statements == 'Y')
			{
				
			}
			
			// TODO Improve this piece of code
			// This code trims values from char type columns
			$col_types = cubrid_column_types ($result);
			$col_names = cubrid_column_names ($result);
			$max = count ($col_types);

			for ($count = 0; $count < $max; $count++) {
				if (preg_match ("/^char/", $col_types[$count]) > 0) {
					$char_type_fields[] = $col_names[$count];
				}
			}

			while ($tmp = cubrid_fetch ($result, CUBRID_OBJECT)) {
				if (is_array ($char_type_fields)) {
					foreach ($char_type_fields as $val) {
						$tmp->{$val} = rtrim ($tmp->{$val});
					}
				}

				if($arrayIndexEndValue) $output[$arrayIndexEndValue--] = $tmp;
				else $output[] = $tmp;
			}

			unset ($char_type_fields);

			if ($result) cubrid_close_request($result);

                        if(count($output)==1){
                            // If call is made for pagination, always return array
                            if(isset($arrayIndexEndValue)) return $output;
                            // Else return object instead of array
                            else return $output[0];
                        }
                        return $output;
		}

		/**
		 * Return the sequence value incremented by 1
		 * Auto_increment column only used in the CUBRID sequence table
		 * @return int
		 */
		function getNextSequence()
		{
			$this->_makeSequence();

			$query = sprintf ("select \"%ssequence\".\"nextval\" as \"seq\" from db_root", $this->prefix);
			$result = $this->_query($query);
			$output = $this->_fetch($result);

			return $output->seq;
		}

		/**
		 * if the table already exists, set the status to GLOBALS
		 * @return void
		 */
		function _makeSequence()
		{
			if($_GLOBALS['XE_EXISTS_SEQUENCE']) return;

			// check cubrid serial
			$query = sprintf('select count(*) as "count" from "db_serial" where name=\'%ssequence\'', $this->prefix);
			$result = $this->_query($query);
			$output = $this->_fetch($result);

			// if do not create serial
			if ($output->count == 0) {
				$query = sprintf('select max("a"."srl") as "srl" from '.
								 '( select max("document_srl") as "srl" from '.
								 '"%sdocuments" UNION '.
								 'select max("comment_srl") as "srl" from '.
								 '"%scomments" UNION '.
								 'select max("member_srl") as "srl" from '.
								 '"%smember"'.
								  ') as "a"', $this->prefix, $this->prefix, $this->prefix);

				$result = $this->_query($query);
				$output = $this->_fetch($result);
				$srl = $output->srl;
				if ($srl < 1) {
					$start = 1;
				}
				else {
					$start = $srl + 1000000;
				}

				// create sequence
				$query = sprintf('create serial "%ssequence" start with %s increment by 1 minvalue 1 maxvalue 10000000000000000000000000000000000000 nocycle;', $this->prefix, $start);
				$this->_query($query);
			}

			$_GLOBALS['XE_EXISTS_SEQUENCE'] = TRUE;
		}


		/**
		 * Check a table exists status
		 * @param string $target_name
		 * @return boolean
		 */
		function isTableExists ($target_name)
		{
			if($target_name == 'sequence') {
				$query = sprintf ("select \"name\" from \"db_serial\" where \"name\" = '%s%s'", $this->prefix, $target_name);
			}
			else {
				$query = sprintf ("select \"class_name\" from \"db_class\" where \"class_name\" = '%s%s'", $this->prefix, $target_name);
			}

			$result = $this->_query ($query);
			if (cubrid_num_rows($result) > 0) {
				$output = TRUE;
			}
			else {
				$output = FALSE;
			}

			if ($result) cubrid_close_request ($result);

			return $output;
		}

		/**
		 * Add a column to the table
		 * @param string $table_name table name
		 * @param string $column_name column name
		 * @param string $type column type, default value is 'number'
		 * @param int $size column size
		 * @param string|int $default default value
		 * @param boolean $notnull not null status, default value is false
		 * @return void
		 */
		function addColumn($table_name, $column_name, $type = 'number', $size = '', $default = '', $notnull = FALSE)
		{
			$type = strtoupper($this->column_type[$type]);
			if ($type == 'INTEGER') $size = '';

			$query = sprintf ("alter class \"%s%s\" add \"%s\" ", $this->prefix, $table_name, $column_name);

			if ($type == 'char' || $type == 'varchar') {
				if ($size) $size = $size * 3;
			}

			if ($size) {
				$query .= sprintf ("%s(%s) ", $type, $size);
			}
			else {
				$query .= sprintf ("%s ", $type);
			}

			if ($default) {
				if ($type == 'INTEGER' || $type == 'BIGINT' || $type=='INT') {
					$query .= sprintf ("default %d ", $default);
				}
				else {
					$query .= sprintf ("default '%s' ", $default);
				}
			}

			if ($notnull) $query .= "not null ";

			$this->_query ($query);
		}

		/**
		 * Drop a column from the table
		 * @param string $table_name table name
		 * @param string $column_name column name
		 * @return void
		 */
		function dropColumn ($table_name, $column_name)
		{
			$query = sprintf ("alter class \"%s%s\" drop \"%s\" ", $this->prefix, $table_name, $column_name);

			$this->_query ($query);
		}

		/**
		 * Check column exist status of the table
		 * @param string $table_name table name
		 * @param string $column_name column name
		 * @return boolean
		 */
		function isColumnExists ($table_name, $column_name)
		{
			$query = sprintf ("select \"attr_name\" from \"db_attribute\" where ".  "\"attr_name\" ='%s' and \"class_name\" = '%s%s'", $column_name, $this->prefix, $table_name);
			$result = $this->_query ($query);

			if (cubrid_num_rows ($result) > 0) $output = TRUE;
			else $output = FALSE;

			if ($result) cubrid_close_request ($result);

			return $output;
		}

		/**
		 * Add an index to the table
		 * $target_columns = array(col1, col2)
		 * $is_unique? unique : none
		 * @param string $table_name table name
		 * @param string $index_name index name
		 * @param string|array $target_columns target column or columns
		 * @param boolean $is_unique
		 * @return void
		 */
		function addIndex ($table_name, $index_name, $target_columns, $is_unique = FALSE)
		{
			if (!is_array ($target_columns)) {
				$target_columns = array ($target_columns);
			}

			$query = sprintf ("create %s index \"%s\" on \"%s%s\" (%s);", $is_unique?'unique':'', $index_name, $this->prefix, $table_name, '"'.implode('","',$target_columns).'"');

			$this->_query ($query);
		}

		/**
		 * Drop an index from the table
		 * @param string $table_name table name
		 * @param string $index_name index name
		 * @param boolean $is_unique
		 * @return void
		 */
		function dropIndex ($table_name, $index_name, $is_unique = FALSE)
		{
			$query = sprintf ("drop %s index \"%s\" on \"%s%s\"", $is_unique?'unique':'', $index_name, $this->prefix, $table_name);

			$this->_query($query);
		}

		/**
		 * Check index status of the table
		 * @param string $table_name table name
		 * @param string $index_name index name
		 * @return boolean
		 */
		function isIndexExists ($table_name, $index_name)
		{
			$query = sprintf ("select \"index_name\" from \"db_index\" where ".  "\"class_name\" = '%s%s' and (\"index_name\" = '%s' or \"index_name\" = '%s') ", $this->prefix, $table_name, $this->prefix .$index_name, $index_name);
			$result = $this->_query ($query);

			if ($this->isError ()) return FALSE;

			$output = $this->_fetch ($result);

			if (!$output) return FALSE;
			return TRUE;
		}

		/**
		 * Delete duplicated index of the table
		 * @return boolean
		 */
        function deleteDuplicateIndexes()
        {
            $query = sprintf("
                        select \"class_name\"
                                , case
                                when substr(\"index_name\", 0, %d) = '%s'
                                    then substr(\"index_name\", %d)
                                else \"index_name\" end as unprefixed_index_name
                                , \"is_unique\"
                          from \"db_index\"
                          where \"class_name\" like %s
                          group by \"class_name\"
                                  , case
                                      when substr(\"index_name\", 0, %d) = '%s'
                                         then substr(\"index_name\", %d)
                                      else \"index_name\"
                                    end
                          having count(*) > 1
                        ", strlen($this->prefix)
                        , $this->prefix
                        , strlen($this->prefix) + 1
                        , "'" . $this->prefix . '%' . "'"
                        , strlen($this->prefix)
                        , $this->prefix
                        , strlen($this->prefix) + 1
                        );
            $result = $this->_query ($query);

            if ($this->isError ()) return FALSE;

            $output = $this->_fetch ($result);
            if (!$output) return FALSE;

			if(!is_array($output)) {
				$indexes_to_be_deleted = array($output);
			}
			else {
				$indexes_to_be_deleted = $output;
			}

            foreach($indexes_to_be_deleted as $index)
            {
                $this->dropIndex(substr($index->class_name, strlen($this->prefix))
						, $this->prefix . $index->unprefixed_index_name
						, $index->is_unique == 'YES' ? TRUE : FALSE);
            }

            return TRUE;
        }

		/**
		 * Creates a table by using xml contents
		 * @param string $xml_doc xml schema contents
		 * @return void|object
		 */
		function createTableByXml ($xml_doc)
		{
			return $this->_createTable ($xml_doc);
		}

		/**
		 * Creates a table by using xml file path
		 * @param string $file_name xml schema file path
		 * @return void|object
		 */
		function createTableByXmlFile ($file_name)
		{
			if (!file_exists ($file_name)) return;
			// read xml file
			$buff = FileHandler::readFile ($file_name);
			return $this->_createTable ($buff);
		}

		/**
		 * Create table by using the schema xml
		 *
		 * type : number, varchar, tinytext, text, bigtext, char, date, \n
		 * opt : notnull, default, size\n
		 * index : primary key, index, unique\n
		 * @param string $xml_doc xml schema contents
		 * @return void|object
		 */
		function _createTable ($xml_doc)
		{
			// xml parsing
			$oXml = new XmlParser();
			$xml_obj = $oXml->parse($xml_doc);
			// Create a table schema
			$table_name = $xml_obj->table->attrs->name;

			// if the table already exists exit function
			if ($this->isTableExists($table_name)) return;

			// If the table name is sequence, it creates a serial
			if ($table_name == 'sequence') {
				$query = sprintf ('create serial "%s" start with 1 increment by 1'.
								  ' minvalue 1 '.
								  'maxvalue 10000000000000000000000000000000000000'.  ' nocycle;', $this->prefix.$table_name);

				return $this->_query($query);
			}


			$table_name = $this->prefix.$table_name;

			$query = sprintf ('create class "%s";', $table_name);
			$this->_query ($query);

			if (!is_array ($xml_obj->table->column)) {
				$columns[] = $xml_obj->table->column;
			}
			else {
				$columns = $xml_obj->table->column;
			}

			$query = sprintf ("alter class \"%s\" add attribute ", $table_name);

			$primary_list = array();
			$unique_list = array();
			$index_list = array();

			foreach ($columns as $column) {
				$name = $column->attrs->name;
				$type = $column->attrs->type;
				$size = $column->attrs->size;
				$notnull = $column->attrs->notnull;
				$primary_key = $column->attrs->primary_key;
				$index = $column->attrs->index;
				$unique = $column->attrs->unique;
				$default = $column->attrs->default;

				switch ($this->column_type[$type]) {
					case 'integer' :
						$size = NULL;
						break;
					case 'text' :
						$size = NULL;
						break;
				}

				if (isset ($default) && ($type == 'varchar' || $type == 'char' ||
				  $type == 'text' || $type == 'tinytext' || $type == 'bigtext')) {
					$default = sprintf ("'%s'", $default);
				}

				if ($type == 'varchar' || $type == 'char') {
					if($size) $size = $size * 3;
				}


				$column_schema[] = sprintf ('"%s" %s%s %s %s',
									$name,
									$this->column_type[$type],
									$size?'('.$size.')':'',
									isset($default)?"default ".$default:'',
									$notnull?'not null':'');

				if ($primary_key) {
					$primary_list[] = $name;
				}
				else if ($unique) {
					$unique_list[$unique][] = $name;
				}
				else if ($index) {
					$index_list[$index][] = $name;
				}
			}

			$query .= implode (',', $column_schema).';';
			$this->_query ($query);

			if (count ($primary_list)) {
				$query = sprintf ("alter class \"%s\" add attribute constraint ".  "\"pkey_%s\" PRIMARY KEY(%s);", $table_name, $table_name, '"'.implode('","',$primary_list).'"');
				$this->_query ($query);
			}

			if (count ($unique_list)) {
				foreach ($unique_list as $key => $val) {
					$query = sprintf ("create unique index \"%s\" on \"%s\" ".  "(%s);", $key, $table_name, '"'.implode('","', $val).'"');
					$this->_query ($query);
				}
			}

			if (count ($index_list)) {
				foreach ($index_list as $key => $val) {
					$query = sprintf ("create index \"%s\" on \"%s\" (%s);", $key, $table_name, '"'.implode('","',$val).'"');
					$this->_query ($query);
				}
			}
		}




		/**
		 * Handles insertAct
		 * @param Object $queryObject
		 * @param boolean $with_values
		 * @return resource
		 */
		function _executeInsertAct($queryObject, $with_values = TRUE)
		{
			if($this->use_prepared_statements == 'Y')
			{
				$this->param = $queryObject->getArguments();
				$with_values = FALSE;
			}
			$query = $this->getInsertSql($queryObject, $with_values);
			if(is_a($query, 'Object')) return;

			$query .= (__DEBUG_QUERY__&1 && $this->query_id)?sprintf (' '.$this->comment_syntax, $this->query_id):'';

			$result = $this->_query ($query);
			if ($result && !$this->transaction_started) {
				$this->_commit();
			}
			unset($this->param);
			return $result;
		}

		/**
		 * Handles updateAct
		 * @param Object $queryObject
		 * @param boolean $with_values
		 * @return resource
		 */
		function _executeUpdateAct($queryObject, $with_values = TRUE)
		{
			if($this->use_prepared_statements == 'Y')
			{
				$this->param = $queryObject->getArguments();
				$with_values = FALSE;
			}
			$query = $this->getUpdateSql($queryObject, $with_values);
			if(is_a($query, 'Object')) return;

			$query .= (__DEBUG_QUERY__&1 && $this->query_id)?sprintf (' '.$this->comment_syntax, $this->query_id):'';

			$result = $this->_query($query);

			if ($result && !$this->transaction_started) $this->_commit();
			unset($this->param);
			return $result;
		}


		/**
		 * Handles deleteAct
		 * @param Object $queryObject
		 * @param boolean $with_values
		 * @return resource
		 */
		function _executeDeleteAct($queryObject, $with_values = TRUE)
		{
			if($this->use_prepared_statements == 'Y')
			{
				$this->param = $queryObject->getArguments();
				$with_values = FALSE;
			}			
			$query =  $this->getDeleteSql($queryObject, $with_values);
			if(is_a($query, 'Object')) return;

			$query .= (__DEBUG_QUERY__&1 && $this->query_id)?sprintf (' '.$this->comment_syntax, $this->query_id):'';

			$result = $this->_query ($query);

			if ($result && !$this->transaction_started) $this->_commit();
			
			unset($this->param);
			return $result;
		}

		/**
		 * Handle selectAct
		 * To get a specific page list easily in select statement,
		 * a method, navigation, is used
		 * @param Object $queryObject
		 * @param resource $connection
		 * @param boolean $with_values
		 * @return Object
		 */
	   function _executeSelectAct($queryObject, $connection = NULL, $with_values = TRUE) {
			if ($this->use_prepared_statements == 'Y') {
				$this->param = $queryObject->getArguments();
				$with_values = FALSE;
			}
			$limit = $queryObject->getLimit();
			if ($limit && $limit->isPageHandler())
			{
				return $this->queryPageLimit($queryObject, $connection, $with_values);
			}
			else {
				$query = $this->getSelectSql($queryObject, $with_values);
				if (is_a($query, 'Object'))
					return;

				$query .= (__DEBUG_QUERY__ & 1 && $this->query_id) ? sprintf(' ' . $this->comment_syntax, $this->query_id) : '';
				$result = $this->_query($query, $connection);

				if ($this->isError())
					return $this->queryError($queryObject);

				$data = $this->_fetch($result);
				$buff = new Object ();
				$buff->data = $data;
				
				unset($this->param);
				return $buff;
			}
		}

		/**
		 * If have a error, return error object
		 * @param Object $queryObject
		 * @return Object
		 */
		function queryError($queryObject){
                        $limit = $queryObject->getLimit();
			if ($limit && $limit->isPageHandler()){
					$buff = new Object ();
					$buff->total_count = 0;
					$buff->total_page = 0;
					$buff->page = 1;
					$buff->data = array ();
					$buff->page_navigation = new PageHandler (/*$total_count*/0, /*$total_page*/1, /*$page*/1, /*$page_count*/10);//default page handler values
					return $buff;
				}else
					return;
		}

		/**
		 * If select query execute, return page info
		 * @param Object $queryObject
		 * @param resource $connection
		 * @param boolean $with_values
		 * @return Object Object with page info containing
		 */
		function queryPageLimit($queryObject, $connection, $with_values){
            $limit = $queryObject->getLimit();
		 	// Total count
			$temp_where = $queryObject->getWhereString($with_values, FALSE);
		 	$count_query = sprintf('select count(*) as "count" %s %s', 'FROM ' . $queryObject->getFromString($with_values), ($temp_where === '' ? '' : ' WHERE '. $temp_where));

            // Check for distinct query and if found update count query structure
            $temp_select = $queryObject->getSelectString($with_values);
            $uses_distinct = strpos(strtolower($temp_select), "distinct") !== FALSE;
            $uses_groupby = $queryObject->getGroupByString() != '';
            if($uses_distinct || $uses_groupby) {
                $count_query = sprintf('select %s %s %s %s'
                    , $temp_select
                    , 'FROM ' . $queryObject->getFromString($with_values)
                    , ($temp_where === '' ? '' : ' WHERE '. $temp_where)
                    , ($uses_groupby ? ' GROUP BY ' . $queryObject->getGroupByString() : '')
                );

                // If query uses grouping or distinct, count from original select
                $count_query = sprintf('select count(*) as "count" from (%s) xet', $count_query);
            }

			$count_query .= (__DEBUG_QUERY__&1 && $queryObject->queryID)?sprintf (' '.$this->comment_syntax, $queryObject->queryID):'';
			$result = $this->_query($count_query, $connection);
			$count_output = $this->_fetch($result);
			$total_count = (int)(isset($count_output->count) ? $count_output->count : NULL);

			$list_count = $limit->list_count->getValue();
			if (!$list_count) $list_count = 20;
			$page_count = $limit->page_count->getValue();
			if (!$page_count) $page_count = 10;
			$page = $limit->page->getValue();
			if (!$page) $page = 1;

			// total pages
			if ($total_count) {
				$total_page = (int) (($total_count - 1) / $list_count) + 1;
			}
			else {
				$total_page = 1;
			}

            // check the page variables
            if ($page > $total_page) {
				// If requested page is bigger than total number of pages, return empty list
				
				$buff = new Object ();		
				$buff->total_count = $total_count;
				$buff->total_page = $total_page;
				$buff->page = $page;
				$buff->data = array();
				$buff->page_navigation = new PageHandler($total_count, $total_page, $page, $page_count);				
				return $buff;
			}
			$start_count = ($page - 1) * $list_count;

			$query = $this->getSelectPageSql($queryObject, $with_values, $start_count, $list_count);
			$query .= (__DEBUG_QUERY__&1 && $queryObject->query_id)?sprintf (' '.$this->comment_syntax, $this->query_id):'';
			$result = $this->_query ($query, $connection);
			if ($this->isError ())
				return $this->queryError($queryObject);

	 		$virtual_no = $total_count - ($page - 1) * $list_count;
	 		$data = $this->_fetch($result, $virtual_no);

	 		$buff = new Object ();
			$buff->total_count = $total_count;
			$buff->total_page = $total_page;
			$buff->page = $page;
			$buff->data = $data;
			$buff->page_navigation = new PageHandler($total_count, $total_page, $page, $page_count);
			unset($this->param);
			return $buff;
		}

		/**
		 * Return the DBParser
		 * @param boolean $force
		 * @return DBParser
		 */
		function getParser($force = FALSE){
			return new DBParser('"', '"', $this->prefix);
		}

		/**
		 * If select query execute, return paging sql
		 * @param object $query
		 * @param boolean $with_values
		 * @param int $start_count
		 * @param int $list_count
		 * @return string select paging sql
		 */
                function getSelectPageSql($query, $with_values = TRUE, $start_count = 0, $list_count = 0) {

                    $select = $query->getSelectString($with_values);
                    if($select == '') return new Object(-1, "Invalid query");
                    $select = 'SELECT ' .$select;

                    $from = $query->getFromString($with_values);
                    if($from == '') return new Object(-1, "Invalid query");
                    $from = ' FROM '.$from;

                    $where = $query->getWhereString($with_values);
                    if($where != '')
                        $where = ' WHERE ' . $where;

                    $groupBy = $query->getGroupByString();
                    if($groupBy != '') $groupBy = ' GROUP BY ' . $groupBy;

                    $orderBy = $query->getOrderByString();
                    if($orderBy != '') $orderBy = ' ORDER BY ' . $orderBy;

                    $limit = $query->getLimitString();
		    if ($limit != '') $limit = sprintf (' LIMIT %d, %d', $start_count, $list_count);

                    return $select . ' ' . $from . ' ' . $where . ' ' . $groupBy . ' ' . $orderBy . ' ' . $limit;
                }
}
?>
