<?php

	class kCountHelper extends kHelper {
	
		
		function kCountHelper()
		{
			parent::kHelper();
			
			// reset expired counts
			$sql = 'UPDATE '.TABLE_PREFIX.'Counters
					SET CountValue = NULL
					WHERE (LifeTime > 0) AND (LastCounted < '.adodb_mktime().' - LifeTime)';
			$this->Conn->Query($sql);
		}
		
		/**
		 * Returns counter value
		 *
		 * @param string $name counter name
		 * @param Array $params counter parameters
		 * @param string $query_name specify query name directly (don't generate from parmeters)
		 * @param bool $multiple_results
		 * @return mixed
		 */
		function getCounter($name, $params = Array (), $query_name = null, $multiple_results = false)
		{
			$clone_counter = false;
			$query_name = isset($query_name) ? $query_name : rtrim($name.'-'.implode('-', array_values($params)), '-');
			$sql = 'SELECT *
					FROM '.TABLE_PREFIX.'Counters
					WHERE Name = '.$this->Conn->qstr($query_name);
			$count_data = $this->Conn->GetRow($sql);
			
			if (!$count_data && ($query_name != $name)) {
				// cloned record not found -> search for origial one
				$sql = 'SELECT *
						FROM '.TABLE_PREFIX.'Counters
						WHERE Name = '.$this->Conn->qstr($name);
				$count_data = $this->Conn->GetRow($sql);
				$clone_counter = true;
			}
			
			if (is_null($count_data['CountValue'])) {
				$params['PREFIX'] = TABLE_PREFIX;
				$count_sql = $count_data['CountQuery'];
				
				foreach ($params as $replace_from => $replace_to) {
					$count_sql = str_replace('<%'.$replace_from.'%>', $replace_to, $count_sql);
				}
				
				if ($multiple_results) {
					$count_data['CountValue'] = serialize($this->Conn->GetCol($count_sql));
				}
				else {
					$count_data['CountValue'] = $this->Conn->GetOne($count_sql);
				}
				
				if ($clone_counter && !$count_data['IsClone']) {
					// don't clone clones
					$count_data['CounterId'] = 0;
					$count_data['Name'] = $query_name;
					$count_data['CountQuery'] = $count_sql;
					$count_data['IsClone'] = 1;
				}
				
				$count_data['LastCounted'] = adodb_mktime();
				$this->Conn->doInsert($count_data, TABLE_PREFIX.'Counters', 'REPLACE');
			}
			
			return $multiple_results ? unserialize($count_data['CountValue']) : $count_data['CountValue'];
		}
		
		/**
		 * Resets counter, whitch are affected by one of specified tables
		 *
		 * @param string $tables comma separated tables list used in counting sqls
		 */
		function resetCounters($tables)
		{
			$tables = explode(',', $tables);
			$prefix_length = strlen(TABLE_PREFIX);
			foreach ($tables as $index => $table) {
				// remove prefixes
				if (substr($table, 0, $prefix_length) == TABLE_PREFIX) {
					$table = substr($table, $prefix_length);
				}
				$tables[$index] = '(TablesAffected LIKE "%|'.$table.'|%")';
			}
			
			$sql = 'UPDATE '.TABLE_PREFIX.'Counters
					SET CountValue = NULL
					WHERE '.implode(' OR ', $tables);
			
			$this->Conn->Query($sql);
		}
		
	}

?>