<?php
/***************************************************************************
 *                                 mssql.php
 *                            -------------------
 *   begin                : Saturday, Feb 13, 2001
 *   copyright            : (C) 2001 The phpBB Group
 *   email                : supportphpbb.com
 *
 *   $Id$
 *
 ***************************************************************************/

/***************************************************************************
 *
 *   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.
 *
 ***************************************************************************/

if (!defined("SQL_LAYER"))
{

define("SQL_LAYER","mssql");

class sql_db
{

	var $db_connect_id;
	var $result;

	var $next_id;
	var $in_transaction = 0;

	var $row = array();
	var $rowset = array();
	var $limit_offset;
	var $query_limit_success;

	var $num_queries = 0;

	function sql_connect($sqlserver, $sqluser, $sqlpassword, $database, $persistency = true)
	{
		$this->persistency = $persistency;
		$this->user = $sqluser;
		$this->server = $sqlserver;
		$this->dbname = $database;

		$this->db_connect_id = ($this->persistency) ? @mssql_pconnect($this->server, $this->user, $sqlpassword) : @mssql_connect($this->server, $this->user, $sqlpassword);

		if ($this->db_connect_id && $this->dbname != '')
		{
			if (!@mssql_select_db($this->dbname, $this->db_connect_id))
			{
				@mssql_close($this->db_connect_id);
				return false;
			}
		}

		return ($this->db_connect_id) ? $this->db_connect_id : $this->sql_error('');
	}

	function sql_return_on_error($fail = false)
	{
		$this->return_on_error = $fail;
	}

	function sql_num_queries()
	{
		return $this->num_queries;
	}

	//
	// Other base methods
	//
	function sql_close()
	{
		if ($this->db_connect_id)
		{
			//
			// Commit any remaining transactions
			//
			if ($this->in_transaction)
			{
				@mssql_query("COMMIT", $this->db_connect_id);
			}

			return @mssql_close($this->db_connect_id);
		}
		else
		{
			return false;
		}
	}


	//
	// Query method
	//
	function sql_query($query = "", $transaction = FALSE)
	{
		//
		// Remove any pre-existing queries
		//
		unset($this->result);
		unset($this->row);

		if ($query != "")
		{
			$this->num_queries++;

			if ($transaction == BEGIN_TRANSACTION && !$this->in_transaction)
			{
				if (!mssql_query("BEGIN TRANSACTION", $this->db_connect_id))
				{
					return false;
				}
				$this->in_transaction = TRUE;
			}

			//
			// Does query contain any LIMIT code? If so pull out relevant start and num_results
			// This isn't terribly easy with MSSQL, whatever you do will potentially impact
			// performance compared to an 'in-built' limit
			//
			// Another issue is the 'lack' of a returned true value when a query is valid but has
			// no result set (as with all the other DB interfaces). It seems though that it's
			// 'fair' to say that if a query returns a false result (ie. no resource id) then the
			// SQL was valid but had no result set. If the query returns nothing but the rowcount
			// returns something then there's a problem. This may well be a false assumption though
			// ... needs checking under Windows itself.
			//
			if (preg_match("/^SELECT(.*?)(LIMIT ([0-9]+)[, ]*([0-9]+)*)?$/s", $query, $limits))
			{
				$query = $limits[1];

				if (!empty($limits[2]))
				{
					$row_offset = ($limits[4]) ? $limits[3] : "";
					$num_rows = ($limits[4]) ? $limits[4] : $limits[3];

					$query = "TOP " . ($row_offset + $num_rows) . $query;
				}

				$this->result = mssql_query("SELECT $query", $this->db_connect_id); 

				if ($this->result)
				{
					$this->limit_offset[$this->result] = (!empty($row_offset)) ? $row_offset : 0;

					if ($row_offset > 0)
					{
						mssql_data_seek($this->result, $row_offset);
					}
				}
			}
			else if (eregi("^INSERT ", $query))
			{
				if (mssql_query($query, $this->db_connect_id))
				{
					$this->result = time() + microtime();

					$result_id = mssql_query("SELECT @@IDENTITY AS id, @@ROWCOUNT as affected", $this->db_connect_id);
					if ($result_id)
					{
						if ($row = mssql_fetch_array($result_id))
						{
							$this->next_id[$this->db_connect_id] = $row['id'];	
							$this->affected_rows[$this->db_connect_id] = $row['affected'];
						}
					}
				}
			}
			else
			{
				if (mssql_query($query, $this->db_connect_id))
				{
					$this->result = time() + microtime();

					$result_id = mssql_query("SELECT @@ROWCOUNT as affected", $this->db_connect_id);
					if ($result_id)
					{
						if ($row = mssql_fetch_array($result_id))
						{
							$this->affected_rows[$this->db_connect_id] = $row['affected'];
						}
					}
				}
			}

			if (!$this->result)
			{
				if ($this->in_transaction)
				{
					mssql_query("ROLLBACK", $this->db_connect_id);
					$this->in_transaction = FALSE;
				}

				return false;
			}

			if ($transaction == END_TRANSACTION && $this->in_transaction)
			{
				$this->in_transaction = FALSE;

				if (!@mssql_query("COMMIT", $this->db_connect_id))
				{
					@mssql_query("ROLLBACK", $this->db_connect_id);
					return false;
				}
			}

			return $this->result;
		}
		else
		{
			if ($transaction == END_TRANSACTION && $this->in_transaction)
			{
				$this->in_transaction = FALSE;

				if (!@mssql_query("COMMIT", $this->db_connect_id))
				{
					@mssql_query("ROLLBACK", $this->db_connect_id);
					return false;
				}
			}

			return true;
		}
	}

	//
	// Other query methods
	//
	function sql_numrows($query_id = 0)
	{
		if (!$query_id)
		{
			$query_id = $this->result;
		}

		if ($query_id)
		{
			return (!empty($this->limit_offset[$query_id])) ? mssql_num_rows($query_id) - $this->limit_offset[$query_id] : @mssql_num_rows($query_id);
		}
		else
		{
			return false;
		}
	}

	function sql_numfields($query_id = 0)
	{
		if (!$query_id)
		{
			$query_id = $this->result;
		}

		return ($query_id) ? mssql_num_fields($query_id) : false;
	}

	function sql_fieldname($offset, $query_id = 0)
	{
		if (!$query_id)
		{
			$query_id = $this->result;
		}

		return ($query_id) ? mssql_field_name($query_id, $offset) : false;
	}

	function sql_fieldtype($offset, $query_id = 0)
	{
		if (!$query_id)
		{
			$query_id = $this->result;
		}

		return ($query_id) ? mssql_field_type($query_id, $offset) : false;
	}

	function sql_fetchrow($query_id = 0)
	{
		if (!$query_id)
		{
			$query_id = $this->result;
		}

		if ($query_id)
		{
			empty($row);

			$row = mssql_fetch_array($query_id);

			foreach ($row as $key => $value)
			{
				$row[$key] = stripslashes($value);
			}

			return $row;
		}
		else
		{
			return false;
		}
	}

	function sql_fetchrowset($query_id = 0)
	{
		if (!$query_id)
		{
			$query_id = $this->result;
		}

		if ($query_id)
		{
			$i = 0;
			$rowset = array();

			while ($row = mssql_fetch_array($query_id))
			{
				foreach ($row as $key => $value)
				{
					$rowset[$i][$key] = stripslashes($value);
				}
				$i++;
			}

			return $rowset;
		}
		else
		{
			return false;
		}
	}

	function sql_fetchfield($field, $row = -1, $query_id)
	{
		if (!$query_id)
		{
			$query_id = $this->result;
		}

		if ($query_id)
		{
			if ($row != -1)
			{
				if ($this->limit_offset[$query_id] > 0)
				{
					$result = (!empty($this->limit_offset[$query_id])) ? mssql_result($this->result, ($this->limit_offset[$query_id] + $row), $field) : false;
				}
				else
				{
					$result = mssql_result($this->result, $row, $field);
				}
			}
			else
			{
				if (empty($this->row[$query_id]))
				{
					$this->row[$query_id] = mssql_fetch_array($query_id);
					$result = stripslashes($this->row[$query_id][$field]);
				}
			}

			return $result;
		}
		else
		{
			return false;
		}
	}

	function sql_rowseek($rownum, $query_id = 0)
	{
		if (!$query_id)
		{
			$query_id = $this->result;
		}

		if ($query_id)
		{
			return (!empty($this->limit_offset[$query_id])) ? mssql_data_seek($query_id, ($this->limit_offset[$query_id] + $rownum)) : mssql_data_seek($query_id, $rownum);
		}
		else
		{
			return false;
		}
	}

	function sql_nextid()
	{
		return ($this->next_id[$this->db_connect_id]) ? $this->next_id[$this->db_connect_id] : false;
	}

	function sql_affectedrows()
	{
		return ($this->affected_rows[$this->db_connect_id]) ? $this->affected_rows[$this->db_connect_id] : false;
	}

	function sql_freeresult($query_id = 0)
	{
		if (!$query_id)
		{
			$query_id = $this->result;
		}

		return ($query_id) ? mssql_free_result($query_id) : false;
	}

	function sql_escape($msg)
	{
		return str_replace("'", "''", str_replace('\\', '\\\\', $msg));
	}

	function sql_error($sql = '')
	{
		if (!$this->return_on_error)
		{
			$this_page = (!empty($_SERVER['PHP_SELF'])) ? $_SERVER['PHP_SELF'] : $_ENV['PHP_SELF'];
			$this_page .= '&' . ((!empty($_SERVER['QUERY_STRING'])) ? $_SERVER['QUERY_STRING'] : $_ENV['QUERY_STRING']);

			$message = '<u>SQL ERROR</u> [ ' . SQL_LAYER . ' ]<br /><br />' . @mssql_get_last_message() . '<br /><br /><u>CALLING PAGE</u><br /><br />'  . htmlspecialchars($this_page) . (($sql != '') ? '<br /><br /><u>SQL</u><br /><br />' . $sql : '') . '<br />';

			if ($this->transaction)
			{
				$this->sql_transaction('rollback');
			}
			
			trigger_error($message, E_USER_ERROR);
		}

		$result = array(
			'message'	=> @mssql_get_last_message(),
			'code'		=> ''
		);

		return $result;
	}

} // class sql_db

} // if ... define

?>