<?php
/*
 *=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
 *  Copyright:
 *
 *  XMLNuke: A Web Development Framework based on XML.
 *
 *  Main Specification and Implementation: Joao Gilberto Magalhaes, joao at byjg dot com
 * 
 *  This file is part of XMLNuke project. Visit http://www.xmlnuke.com
 *  for more information.
 *  
 *  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., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 *
 *=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= 
 */

class SQLType
{
	const SQL_UPDATE = 1;
	const SQL_INSERT = 2;
	const SQL_DELETE = 3;
}

class SQLFieldType
{
	const Literal = 'F';
	const Text = 'T';
	const Number = 'N';
	const Date = 'D';
	const Boolean = 'B';
}

/**
 * SQLHelper Class by Joao Gilberto Magalhaes
 *
 */
class SQLHelper
{
	/**
	 * @var DBDataSet
	 */
	protected $_db;
	
	protected $_fieldDeliLeft = " ";
	protected $_fieldDeliRight = " ";
	
	public function __construct($db)
	{
		if (!($db instanceof DBDataSet) )
		{
			throw new Exception("Constructor must be an DBDataSet object");		
		}
		$this->_db = $db;
	}

	/**
	 * Generate and Execute UPDATE and INSERTS
	 *
	 * @param DBDataSet $db
	 * @param string $table
	 * @param array $fields
	 * @param SQLType $type
	 * @param string $filter
	 * @return string
	 */
	public function generateSQL($table, $fields, &$param, $type = SQLType::SQL_INSERT, $filter = "", $decimalpoint = ".")
	{
		if ((is_null($param)) || (!is_array($param)))
		{
			$param = array();
		}
	
		if ($type == SQLType::SQL_UPDATE)
		{
			$sql = "";
			foreach ($fields as $fieldname=>$fieldvalue)
			{
				if ($sql != "")
				{
					$sql .= ", ";
				}
				$sql .= " " . $this->_fieldDeliLeft . $fieldname . $this->_fieldDeliRight . " = " . $this->getValue($fieldname, $fieldvalue, $param, $decimalpoint) . " ";
			}
			$sql = "update $table set $sql where $filter ";
		}
		elseif ($type == SQLType::SQL_INSERT)
		{
			$sql = "";
			$campos = "";
			$valores = "";
			foreach ($fields as $fieldname => $fieldvalue)
			{
				if ($campos != "")
				{
					$campos .= ", ";
					$valores .= ", ";
				}
				$campos .= $this->_fieldDeliLeft . $fieldname . $this->_fieldDeliRight;
				$valores .= $this->getValue($fieldname, $fieldvalue, $param, $decimalpoint);
			}
			$sql = "insert into $table ($campos) values ($valores)";
		}
		elseif ($type == SQLType::SQL_DELETE) 
		{
			if ($filter == "")
			{
				throw new Exception("I can't generate delete statements without filter");
			}
			$sql = "delete from $table where $filter";
		}
		return $sql;
	}
	
	/**
	 * Generic Function
	 *
	 * @param unknown_type $valores
	 * @return unknown
	 */
	protected function getValue($name, $valores, &$param, $decimalpoint)
	{
		$paramName = "[[" . $name . "]]";
		if (!is_array($valores))
		{
			throw new Exception("The pair of values must be an array of TWO elements");
		}
		//$valores[1]= str_replace("'", "''", $valores[1]);
		if ($valores[0]== SQLFieldType::Boolean)
		{
			if ($valores[1]=="1")
			{
				$param[$name] = 'S';
			}
			else 
			{
				$param[$name] = 'N';
			}
			return $paramName;
		}
		elseif ($valores[1] == "") 
		{
			return "null";
		}
		elseif ($valores[0]==SQLFieldType::Text)
		{
			$param[$name] = trim($valores[1]);
			return $paramName;
		}
		elseif ($valores[0]==SQLFieldType::Date)
		{
			$dateStamp = DateUtil::TimeStampFromStr($valores[1], DATEFORMAT::DMY);
			$date = DateUtil::FormatDate($dateStamp, DATEFORMAT::YMD);
			$param[$name] = $date;
			if ( ($this->_db->getDbType() == 'oci8') || ( ($this->_db->getDbType() == 'dsn') && (strpos($this->_db->getDbConnectionString(), "oci8"))) )
			{
				return "TO_DATE($paramName, 'YYYY-MM-DD')";
			}
			else 
			{
				return $paramName;
			}
		}
		elseif ($valores[0]==SQLFieldType::Number)
		{
			$search = ($decimalpoint == ".") ? "," : ".";
			$valores[1] = trim(str_replace($search, $decimalpoint, $valores[1]));
			$param[$name] = $valores[1];
			return $paramName;
		}
		else
		{
			return $valores[1];
		}
	}
	
	/**
	 * Used to create a FILTER in a SQL string.
	 *
	 * @param string $fieldName
	 * @param Relation $relation
	 * @param array() $value
	 * @param &string $sql (Full SQL)
	 * @param &string $param
	 */
	public function getWhereClause($fieldName, $relation, $value, &$sql, &$param)
	{
		if (strlen($sql)>4)
		{
			$sql .= ' and ';
		}
		$sql = " $fieldName " . $relation . " " . $this->getValue($fieldName, $value, $param, $decimalpoint);
	}
	
	
	public function setFieldDelimeters($left, $right)
	{
		$this->_fieldDeliLeft = $left;
		$this->_fieldDeliRight = $right;
	}
}
?>