<?php

	class SpamHelper extends kHelper {
	
		/**
		 * Table name where spam control information is keeped
		 *
		 * @var string
		 */
		var $TableName;
		
		/**
		 * RecourceId field of current item
		 *
		 * @var int
		 */
		var $ResourceId = 0;
		
		/**
		 * Type of information to put into spam control
		 *
		 * @var string
		 */
		var $DataType = '';
		
		/**
		 * Default spam control record expiration
		 *
		 * @var int
		 */
		var $Expiration = 0;
		
		function SpamHelper()
		{
			parent::kHelper();
			$this->TableName = TABLE_PREFIX.'SpamControl';
		}
		
		/**
		 * Initializes helper for concrete item
		 *
		 * @param int $resource_id
		 * @param string $data_type
		 * @param int $expiration
		 */
		function InitHelper($resource_id, $data_type, $expiration)
		{
			$this->ResourceId = $resource_id;
			$this->DataType = $data_type;
			
			if (preg_match('/(.*):(.*)/', $expiration, $regs)) {
				$delay_value = $this->Application->ConfigValue($regs[1]);
				$delay_interval = $this->Application->ConfigValue($regs[2]);
				$expiration = $delay_value * $delay_interval;
			}
			
			$this->Expiration = adodb_mktime() + $expiration;
		}
		
		/**
		 * Returns WHERE clause that identified each spam control record
		 *
		 * @param bool $as_array return result as array, not string
		 * 
		 * @return string
		 */
		function GetKeyClause($as_array = false)
		{
			$user_id = $this->Application->RecallVar('user_id');
			
			if ($user_id == 0) {
				$user_id = -2;
			}
			
			$keys = Array (
				'ItemResourceId'	=>	$this->ResourceId,
				'IPaddress'			=>	$_SERVER['REMOTE_ADDR'],
				'PortalUserId'		=>	$user_id,
				'DataType'			=>	$this->DataType,
			);
			
			if ($as_array) {
				return $keys;
			}
			
			$ret = '';
			foreach ($keys as $field_name => $field_value) {
				$ret .= '('.$field_name.' = '.$this->Conn->qstr($field_value).') AND ';
			}
			
			return preg_replace('/(.*) AND $/', '\\1', $ret);
		}
		
		/**
		 * Allows to add current item in spam control
		 *
		 */
		function AddToSpamControl()
		{
			$fields_hash = $this->GetKeyClause(true);
			
			$fields_hash['Expire'] = $this->Expiration;
			$this->Conn->doInsert($fields_hash, $this->TableName);
		}
		
		/**
		 * Allows to check if current item is in spam control
		 *
		 * @return bool
		 */
		function InSpamControl()
		{
			$key_clause = $this->GetKeyClause();
			
			$sql = 'SELECT Expire
					FROM '.$this->TableName.'
					WHERE '.$key_clause;
			$expires = $this->Conn->GetOne($sql);
	
			if ($expires && $expires < adodb_mktime()) {
				// spam control record is expired
				$sql = 'DELETE FROM '.$this->TableName.'
						WHERE '.$key_clause;
				$this->Conn->Query($sql);
				return false;
			}
			
			return $expires ? true : false;
		}
		
	}

?>