<?php
/********************************************************************
Project: sql_Generator
Version: 0.9
Author: Carsten Gehling (hide@address.com)
Date: 2003-07-29

Copyright (c) 2003 Carsten Gehling <hide@address.com>
-------------------------------------------------------
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.

This library 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
Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA

NOTES FROM AUTHOR
-------------------
If you make any change in the code, please let me know by email.
If I find your enhancements useful, I will publish a new version
with the changes, of course with credit to you.
********************************************************************/

/////////////////////////////////////////////////////////////////////
// Class sql_Generator
// ------------------------------------------------------------------
// This class is used to generate insert and update sql statements
//
// Usage:
// 
class sql_Generator {
	// private
	var $tablename = "";
	var $fields = array();

	// public
	function sql_Generator($tablename = "") {
		if ($tablename != "")
			$this->create($tablename);
	}

	// public
	function create($tablename) {
		$this->tablename = $tablename;
		$this->fields = array();
	}

	// public
	function addField($key, $value, $type = "string") {
		$this->fields[$key] = array("type" => $type, "value" => $value);
	}

	// public
	function makeInsert() {
		if ($this->tablename == "")
			return "";
		if (count($this->fields) == 0)
			return "";

		$sql_key = "";
		$sql_val = "";
		reset($this->fields);
		while (list($key, $field) = each($this->fields)) {
			$val = $field["value"];
			if (is_string($val))
				$val = addslashes($val);
			if ($field["type"] == "string")
				$val = "'$val'";
			$sql_key .= ($sql_key != "" ? ", " : "") . "$key";
			$sql_val .= ($sql_val != "" ? ", " : "") . "$val";
		}
		$sql = "insert into $this->tablename ($sql_key) values ($sql_val) ";
		return $sql;
	}

	// public
	function makeUpdateKey($key, $value, $type = "string") {
		if (is_string($value))
			$value = addslashes($value);
		if ($type == "string")
			$value = "'$value'";
		return $this->makeUpdate("$key = $value");
	}

	// public
	function makeUpdate($whereexpr) {
		if ($this->tablename == "")
			return "";
		if (count($this->fields) == 0)
			return "";

		$sql_upd = "";
		reset($this->fields);
		while (list($key, $field) = each($this->fields)) {
			$val = $field["value"];
			if (is_string($val))
				$val = addslashes($val);
			if ($field["type"] == "string")
				$val = "'$val'";
			$sql_upd .= ($sql_upd != "" ? ", " : "") . "$key = $val ";
		}
		$sql = "update $this->tablename set $sql_upd ";
		$sql .= "where $whereexpr ";
		return $sql;
	}
}
?>