<?php
// Copyright (c) 2004 ars Cognita Inc., all rights reserved
/* ******************************************************************************
    Released under both BSD license and Lesser GPL library license. 
 	Whenever there is any discrepancy between the two licenses, 
 	the BSD license will take precedence. 
	
Redistribution and use in source and binary forms, with or without modification,
are permitted provided that the following conditions are met:

Redistributions of source code must retain the above copyright notice, this list
 of conditions and the following disclaimer.
Redistributions in binary form must reproduce the above copyright notice, this l
ist of conditions and the following disclaimer in the documentation and/or other
 materials provided with the distribution.
Neither the name of the ars Cognita, Inc.,  nor the names of its contributors may be used 
to endorse or promote products derived from this software without specific prior
written permission.

DISCLAIMER:
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WA
RRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIREC
T, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR P
ROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWI
SE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE P
OSSIBILITY OF SUCH DAMAGE.

*******************************************************************************/
/**
 * xmlschema is a class that allows the user to quickly and easily
 * build a database on any ADOdb-supported platform using a simple
 * XML schema.
 *
 * Last Editor: $Author: ajdonnison $
 * @author Richard Tango-Lowy & Dan Cech
 * @version $Revision: 1.2 $
 *
 * @package axmls
 * @tutorial getting_started.pkg
 */

/**
* Debug on or off
*/
if( !defined( 'XMLS_DEBUG' ) ) {
	define( 'XMLS_DEBUG', FALSE );
}

/**
* Default prefix key
*/
if( !defined( 'XMLS_PREFIX' ) ) {
	define( 'XMLS_PREFIX', '%%P' );
}

/**
* Maximum length allowed for object prefix
*/
if( !defined( 'XMLS_PREFIX_MAXLEN' ) ) {
	define( 'XMLS_PREFIX_MAXLEN', 10 );
}

/**
* Execute SQL inline as it is generated
*/
if( !defined( 'XMLS_EXECUTE_INLINE' ) ) {
	define( 'XMLS_EXECUTE_INLINE', FALSE );
}

/**
* Continue SQL Execution if an error occurs?
*/
if( !defined( 'XMLS_CONTINUE_ON_ERROR' ) ) {
	define( 'XMLS_CONTINUE_ON_ERROR', FALSE );
}

/**
* Current Schema Version
*/
if( !defined( 'XMLS_SCHEMA_VERSION' ) ) {
	define( 'XMLS_SCHEMA_VERSION', '0.2' );
}

/**
* Default Schema Version.  Used for Schemas without an explicit version set.
*/
if( !defined( 'XMLS_DEFAULT_SCHEMA_VERSION' ) ) {
	define( 'XMLS_DEFAULT_SCHEMA_VERSION', '0.1' );
}

/**
* Default Schema Version.  Used for Schemas without an explicit version set.
*/
if( !defined( 'XMLS_DEFAULT_UPGRADE_METHOD' ) ) {
	define( 'XMLS_DEFAULT_UPGRADE_METHOD', 'ALTER' );
}

/**
* Include the main ADODB library
*/
if( !defined( '_ADODB_LAYER' ) ) {
	require( 'adodb.inc.php' );
}

/**
* Abstract DB Object. This class provides basic methods for database objects, such
* as tables and indexes.
*
* @package axmls
* @access private
*/
class dbObject {
	
	/**
	* var object Parent
	*/
	var $parent;
	
	/**
	* var string current element
	*/
	var $currentElement;
	
	/**
	* NOP
	*/
	function dbObject( &$parent, $attributes = NULL ) {
		$this->parent =& $parent;
	}
	
	/**
	* XML Callback to process start elements
	*
	* @access private
	*/
	function _tag_open( &$parser, $tag, $attributes ) {
		
	}
	
	/**
	* XML Callback to process CDATA elements
	*
	* @access private
	*/
	function _tag_cdata( &$parser, $cdata ) {
		
	}
	
	/**
	* XML Callback to process end elements
	*
	* @access private
	*/
	function _tag_close( &$parser, $tag ) {
		
	}
	
	function create() {
		return array();
	}
	
	/**
	* Destroys the object
	*/
	function destroy() {
		unset( $this );
	}
	
	/**
	* Checks whether the specified RDBMS is supported by the current
	* database object or its ranking ancestor.
	*
	* @param string $platform RDBMS platform name (from ADODB platform list).
	* @return boolean TRUE if RDBMS is supported; otherwise returns FALSE.
	*/
	function supportedPlatform( $platform = NULL ) {
		return is_object( $this->parent ) ? $this->parent->supportedPlatform( $platform ) : TRUE;
	}
	
	/**
	* Returns the prefix set by the ranking ancestor of the database object.
	*
	* @param string $name Prefix string.
	* @return string Prefix.
	*/
	function prefix( $name = '' ) {
		return is_object( $this->parent ) ? $this->parent->prefix( $name ) : $name;
	}
	
	/**
	* Extracts a field ID from the specified field.
	*
	* @param string $field Field.
	* @return string Field ID.
	*/
	function FieldID( $field ) {
		return strtoupper( preg_replace( '/^`(.+)`$/', '$1', $field ) );
	}
}

/**
* Creates a table object in ADOdb's datadict format
*
* This class stores information about a database table. As charactaristics
* of the table are loaded from the external source, methods and properties
* of this class are used to build up the table description in ADOdb's
* datadict format.
*
* @package axmls
* @access private
*/
class dbTable extends dbObject {
	
	/**
	* @var string Table name
	*/
	var $name;
	
	/**
	* @var array Field specifier: Meta-information about each field
	*/
	var $fields = array();
	
	/**
	* @var array List of table indexes.
	*/
	var $indexes = array();
	
	/**
	* @var array Table options: Table-level options
	*/
	var $opts = array();
	
	/**
	* @var string Field index: Keeps track of which field is currently being processed
	*/
	var $current_field;
	
	/**
	* @var boolean Mark table for destruction
	* @access private
	*/
	var $drop_table;
	
	/**
	* @var boolean Mark field for destruction (not yet implemented)
	* @access private
	*/
	var $drop_field = array();
	
	/**
	* @var array List of rows of data that needs to be loaded into
	* table once created.
	* @access private
	*/
	var $row_data = array();
	var $current_row = 0;
	var $row_field = 0;

	var $html_table;

	/**
	* Iniitializes a new table object.
	*
	* @param string $prefix DB Object prefix
	* @param array $attributes Array of table attributes.
	*/
	function dbTable( &$parent, $attributes = NULL ) {
		$this->parent =& $parent;
		$this->name = $this->prefix($attributes['NAME']);
		$trans_table = get_html_translation_table(HTML_ENTITIES);
		$this->html_table = array_flip($trans_table);
	}
	
	/**
	* XML Callback to process start elements. Elements currently 
	* processed are: INDEX, DROP, FIELD, KEY, NOTNULL, AUTOINCREMENT & DEFAULT. 
	*
	* @access private
	*/
	function _tag_open( &$parser, $tag, $attributes ) {
		$this->currentElement = strtoupper( $tag );
		
		switch( $this->currentElement ) {
			case 'INDEX':
				xml_set_object( $parser, $this->addIndex( $attributes ) );
				break;
			case 'DROP':
				$this->drop();
				break;
			case 'FIELD':
				// Add a field
				$fieldName = $attributes['NAME'];
				$fieldType = $attributes['TYPE'];
				$fieldSize = isset( $attributes['SIZE'] ) ? $attributes['SIZE'] : NULL;
				$fieldOpts = isset( $attributes['OPTS'] ) ? $attributes['OPTS'] : NULL;
				
				$this->addField( $fieldName, $fieldType, $fieldSize, $fieldOpts );
				break;
			case 'KEY':	
			case 'NOTNULL':
			case 'AUTOINCREMENT':
				// Add a field option
				$this->addFieldOpt( $this->current_field, $this->currentElement );
				break;
			case 'DEFAULT':
				// Add a field option to the table object
				
				// Work around ADOdb datadict issue that misinterprets empty strings.
				if( $attributes['VALUE'] == '' ) {
					$attributes['VALUE'] = " '' ";
				}
				
				$this->addFieldOpt( $this->current_field, $this->currentElement, $attributes['VALUE'] );
				break;
			case 'ROW':
				$this->row_data[$this->current_row] = array();
				$this->row_field = 0;
				break;
			default:
				// print_r( array( $tag, $attributes ) );
		}
	}
	
	/**
	* XML Callback to process CDATA elements
	*
	* @access private
	*/
	function _tag_cdata( &$parser, $cdata ) {
		switch( $this->currentElement ) {
			// Table constraint
			case 'CONSTRAINT':
			// Table option
			case 'OPT':
				$this->addTableOpt( $cdata );
				break;
			case 'F':
				$this->addFieldData($cdata);
				break;
			default:
				
		}
	}
	
	/**
	* XML Callback to process end elements
	*
	* @access private
	*/
	function _tag_close( &$parser, $tag ) {
		$this->currentElement = '';
		
		switch( strtoupper( $tag ) ) {
			case 'TABLE':
				$this->parent->addSQL( $this->create( $this->parent ) );
				xml_set_object( $parser, $this->parent );
				$this->destroy();
				break;
			case 'ROW':
				$this->current_row++;
				break;
			case 'F':
				$this->row_field++;
				break;
		}
	}
	
	/**
	* Adds an index to a table object
	*
	* @param array $attributes Index attributes
	* @return object dbIndex object
	*/
	function &addIndex( $attributes ) {
		$name = strtoupper( $attributes['NAME'] );
		$this->indexes[$name] =& new dbIndex( $this, $attributes );
		return $this->indexes[$name];
	}
	
	/**
	* Adds a field to a table object
	*
	* $name is the name of the table to which the field should be added. 
	* $type is an ADODB datadict field type. The following field types
	* are supported as of ADODB 3.40:
	* 	- C:  varchar
	*	- X:  CLOB (character large object) or largest varchar size
	*	   if CLOB is not supported
	*	- C2: Multibyte varchar
	*	- X2: Multibyte CLOB
	*	- B:  BLOB (binary large object)
	*	- D:  Date (some databases do not support this, and we return a datetime type)
	*	- T:  Datetime or Timestamp
	*	- L:  Integer field suitable for storing booleans (0 or 1)
	*	- I:  Integer (mapped to I4)
	*	- I1: 1-byte integer
	*	- I2: 2-byte integer
	*	- I4: 4-byte integer
	*	- I8: 8-byte integer
	*	- F:  Floating point number
	*	- N:  Numeric or decimal number
	*
	* @param string $name Name of the table to which the field will be added.
	* @param string $type	ADODB datadict field type.
	* @param string $size	Field size
	* @param array $opts	Field options array
	* @return array Field specifier array
	*/
	function addField( $name, $type, $size = NULL, $opts = NULL ) {
		$field_id = $this->FieldID( $name );
		
		// Set the field index so we know where we are
		$this->current_field = $field_id;
		
		// Set the field name (required)
		$this->fields[$field_id]['NAME'] = $name;
		
		// Set the field type (required)
		$this->fields[$field_id]['TYPE'] = $type;
		
		// Set the field size (optional)
		if( isset( $size ) ) {
			$this->fields[$field_id]['SIZE'] = $size;
		}
		
		// Set the field options
		if( isset( $opts ) ) {
			$this->fields[$field_id]['OPTS'] = $opts;
		}
	}
	
	/**
	* Adds a field option to the current field specifier
	*
	* This method adds a field option allowed by the ADOdb datadict 
	* and appends it to the given field.
	*
	* @param string $field	Field name
	* @param string $opt ADOdb field option
	* @param mixed $value Field option value
	* @return array Field specifier array
	*/
	function addFieldOpt( $field, $opt, $value = NULL ) {
		if( !isset( $value ) ) {
			$this->fields[$this->FieldID( $field )]['OPTS'][] = $opt;
		// Add the option and value
		} else {
			$this->fields[$this->FieldID( $field )]['OPTS'][] = array( $opt => $value );
		}
	}
	
	/**
	* Adds an option to the table
	*
	* This method takes a comma-separated list of table-level options
	* and appends them to the table object.
	*
	* @param string $opt Table option
	* @return array Options
	*/
	function addTableOpt( $opt ) {
		$this->opts[] = $opt;
		
		return $this->opts;
	}
	
	function addFieldData($data) {
		$this->row_data[$this->current_row][$this->row_field] = $data;
	}
	/**
	* Generates the SQL that will create the table in the database
	*
	* @param object $xmls adoSchema object
	* @return array Array containing table creation SQL
	*/
	function create( &$xmls ) {
		$sql = array();
		
		// drop any existing indexes
		if( is_array( $legacy_indexes = $xmls->dict->MetaIndexes( $this->name ) ) ) {
			foreach( $legacy_indexes as $index => $index_details ) {
				$sql[] = $xmls->dict->DropIndexSQL( $index, $this->name );
			}
		}
		
		// remove fields to be dropped from table object
		foreach( $this->drop_field as $field ) {
			unset( $this->fields[$field] );
		}
		
		// if table exists
		if( is_array( $legacy_fields = $xmls->dict->MetaColumns( $this->name ) ) ) {
			// drop table
			if( $this->drop_table ) {
				$sql[] = $xmls->dict->DropTableSQL( $this->name );
				
				return $sql;
			}
			
			// drop any existing fields not in schema
			foreach( $legacy_fields as $field_id => $field ) {
				if( !isset( $this->fields[$field_id] ) ) {
					$sql[] = $xmls->dict->DropColumnSQL( $this->name, '`'.$field->name.'`' );
				}
			}
		// if table doesn't exist
		} else {
			if( $this->drop_table ) {
				return $sql;
			}
			
			$legacy_fields = array();
		}
		
		// Loop through the field specifier array, building the associative array for the field options
		$fldarray = array();
		
		foreach( $this->fields as $field_id => $finfo ) {
			// Set an empty size if it isn't supplied
			if( !isset( $finfo['SIZE'] ) ) {
				$finfo['SIZE'] = '';
			}
			
			// Initialize the field array with the type and size
			$fldarray[$field_id] = array(
				'NAME' => $finfo['NAME'],
				'TYPE' => $finfo['TYPE'],
				'SIZE' => $finfo['SIZE']
			);
			
			// Loop through the options array and add the field options. 
			if( isset( $finfo['OPTS'] ) ) {
				foreach( $finfo['OPTS'] as $opt ) {
					// Option has an argument.
					if( is_array( $opt ) ) {
						$key = key( $opt );
						$value = $opt[key( $opt )];
						$fldarray[$field_id][$key] = $value;
					// Option doesn't have arguments
					} else {
						$fldarray[$field_id][$opt] = $opt;
					}
				}
			}
		}
		
		if( empty( $legacy_fields ) ) {
			// Create the new table
			$sql[] = $xmls->dict->CreateTableSQL( $this->name, $fldarray, $this->opts );
			logMsg( end( $sql ), 'Generated CreateTableSQL' );
		} else {
			// Upgrade an existing table
			logMsg( "Upgrading {$this->name} using '{$xmls->upgrade}'" );
			switch( $xmls->upgrade ) {
				// Use ChangeTableSQL
				case 'ALTER':
					logMsg( 'Generated ChangeTableSQL (ALTERing table)' );
					$sql[] = $xmls->dict->ChangeTableSQL( $this->name, $fldarray, $this->opts );
					break;
				case 'REPLACE':
					logMsg( 'Doing upgrade REPLACE (testing)' );
					$sql[] = $xmls->dict->DropTableSQL( $this->name );
					$sql[] = $xmls->dict->CreateTableSQL( $this->name, $fldarray, $this->opts );
					break;
				// ignore table
				default:
					return array();
			}
		}
		
		// Before building indexes, load any data
		foreach ($this->row_data as $row ) {
		  $fname = array();
		  $fdata = array();
		  $fnum = 0;
		  foreach ($fldarray as $finfo) {
		    if (isset($row[$fnum])) {
		      $fname[] = $finfo['NAME'];
		      $val = $this->unhtml($row[$fnum]);
		      $val = str_replace('\'', "\'", $val);
		      $val = str_replace("\r\n", '\n', $val);
		      $fdata[] = str_replace("\n", '\n', $val);
		    }
		    $fnum++;
		  }
		  $sql[] = 'INSERT INTO ' . $this->name . '(`' . implode('`,`', $fname) . '`) VALUES (\'' . implode('\',\'', $fdata) . '\')';
		}

		foreach( $this->indexes as $index ) {
			$sql[] = $index->create( $xmls );
		}
		
		return $sql;
	}
	
	/**
	* Marks a field or table for destruction
	*/
	function drop() {
		if( isset( $this->current_field ) ) {
			// Drop the current field
			logMsg( "Dropping field '{$this->current_field}' from table '{$this->name}'" );
			// $this->drop_field[$this->current_field] = $xmls->dict->DropColumnSQL( $this->name, $this->current_field );
			$this->drop_field[$this->current_field] = $this->current_field;
		} else {
			// Drop the current table
			logMsg( "Dropping table '{$this->name}'" );
			// $this->drop_table = $xmls->dict->DropTableSQL( $this->name );
			$this->drop_table = TRUE;
		}
	}

	function unhtml($string) {
		return strtr($string, $this->html_table);
	}
}

/**
* Creates an index object in ADOdb's datadict format
*
* This class stores information about a database index. As charactaristics
* of the index are loaded from the external source, methods and properties
* of this class are used to build up the index description in ADOdb's
* datadict format.
*
* @package axmls
* @access private
*/
class dbIndex extends dbObject {
	
	/**
	* @var string	Index name
	*/
	var $name;
	
	/**
	* @var array	Index options: Index-level options
	*/
	var $opts = array();
	
	/**
	* @var array	Indexed fields: Table columns included in this index
	*/
	var $columns = array();
	
	/**
	* @var boolean Mark index for destruction
	* @access private
	*/
	var $drop = FALSE;
	
	/**
	* Initializes the new dbIndex object.
	*
	* @param object $parent Parent object
	* @param array $attributes Attributes
	*
	* @internal
	*/
	function dbIndex( &$parent, $attributes = NULL ) {
		$this->parent =& $parent;
		
		$this->name = $this->prefix ($attributes['NAME']);
	}
	
	/**
	* XML Callback to process start elements
	*
	* Processes XML opening tags. 
	* Elements currently processed are: DROP, CLUSTERED, BITMAP, UNIQUE, FULLTEXT & HASH. 
	*
	* @access private
	*/
	function _tag_open( &$parser, $tag, $attributes ) {
		$this->currentElement = strtoupper( $tag );
		
		switch( $this->currentElement ) {
			case 'DROP':
				$this->drop();
				break;
			case 'CLUSTERED':
			case 'BITMAP':
			case 'UNIQUE':
			case 'FULLTEXT':
			case 'HASH':
				// Add index Option
				$this->addIndexOpt( $this->currentElement );
				break;
			default:
				// print_r( array( $tag, $attributes ) );
		}
	}
	
	/**
	* XML Callback to process CDATA elements
	*
	* Processes XML cdata.
	*
	* @access private
	*/
	function _tag_cdata( &$parser, $cdata ) {
		switch( $this->currentElement ) {
			// Index field name
			case 'COL':
				$this->addField( $cdata );
				break;
			default:
				
		}
	}
	
	/**
	* XML Callback to process end elements
	*
	* @access private
	*/
	function _tag_close( &$parser, $tag ) {
		$this->currentElement = '';
		
		switch( strtoupper( $tag ) ) {
			case 'INDEX':
				xml_set_object( $parser, $this->parent );
				break;
		}
	}
	
	/**
	* Adds a field to the index
	*
	* @param string $name Field name
	* @return string Field list
	*/
	function addField( $name ) {
		$this->columns[$this->FieldID( $name )] = $name;
		
		// Return the field list
		return $this->columns;
	}
	
	/**
	* Adds options to the index
	*
	* @param string $opt Comma-separated list of index options.
	* @return string Option list
	*/
	function addIndexOpt( $opt ) {
		$this->opts[] = $opt;
		
		// Return the options list
		return $this->opts;
	}
	
	/**
	* Generates the SQL that will create the index in the database
	*
	* @param object $xmls adoSchema object
	* @return array Array containing index creation SQL
	*/
	function create( &$xmls ) {
		if( $this->drop ) {
			return NULL;
		}
		
		// eliminate any columns that aren't in the table
		foreach( $this->columns as $id => $col ) {
			if( !isset( $this->parent->fields[$id] ) ) {
				unset( $this->columns[$id] );
			}
		}
		
		return $xmls->dict->CreateIndexSQL( $this->name, $this->parent->name, $this->columns, $this->opts );
	}
	
	/**
	* Marks an index for destruction
	*/
	function drop() {
		$this->drop = TRUE;
	}
}

/**
* Creates the SQL to execute a list of provided SQL queries
*
* @package axmls
* @access private
*/
class dbQuerySet extends dbObject {
	
	/**
	* @var array	List of SQL queries
	*/
	var $queries = array();
	
	/**
	* @var string	String used to build of a query line by line
	*/
	var $query;
	
	/**
	* @var string	Query prefix key
	*/
	var $prefixKey = '';
	
	/**
	* @var boolean	Auto prefix enable (TRUE)
	*/
	var $prefixMethod = 'AUTO';
	
	/**
	* Initializes the query set.
	*
	* @param object $parent Parent object
	* @param array $attributes Attributes
	*/
	function dbQuerySet( &$parent, $attributes = NULL ) {
		$this->parent =& $parent;
			
		// Overrides the manual prefix key
		if( isset( $attributes['KEY'] ) ) {
			$this->prefixKey = $attributes['KEY'];
		}
		
		$prefixMethod = isset( $attributes['PREFIXMETHOD'] ) ? strtoupper( trim( $attributes['PREFIXMETHOD'] ) ) : '';
		
		// Enables or disables automatic prefix prepending
		switch( $prefixMethod ) {
			case 'AUTO':
				$this->prefixMethod = 'AUTO';
				break;
			case 'MANUAL':
				$this->prefixMethod = 'MANUAL';
				break;
			case 'NONE':
				$this->prefixMethod = 'NONE';
				break;
			default:
				$this->prefixMethod = 'AUTO';
		}
	}
	
	/**
	* XML Callback to process start elements. Elements currently 
	* processed are: QUERY. 
	*
	* @access private
	*/
	function _tag_open( &$parser, $tag, $attributes ) {
		$this->currentElement = strtoupper( $tag );
		
		switch( $this->currentElement ) {
			case 'QUERY':
				// Create a new query in a SQL queryset.
				// Ignore this query set if a platform is specified and it's different than the 
				// current connection platform.
				if( !isset( $attributes['PLATFORM'] ) OR $this->supportedPlatform( $attributes['PLATFORM'] ) ) {
					$this->newQuery();
				} else {
					$this->discardQuery();
				}
				break;
			default:
				// print_r( array( $tag, $attributes ) );
		}
	}
	
	/**
	* XML Callback to process CDATA elements
	*/
	function _tag_cdata( &$parser, $cdata ) {
		switch( $this->currentElement ) {
			// Line of queryset SQL data
			case 'QUERY':
				$this->buildQuery( $cdata );
				break;
			default:
				
		}
	}
	
	/**
	* XML Callback to process end elements
	*
	* @access private
	*/
	function _tag_close( &$parser, $tag ) {
		$this->currentElement = '';
		
		switch( strtoupper( $tag ) ) {
			case 'QUERY':
				// Add the finished query to the open query set.
				$this->addQuery();
				break;
			case 'SQL':
				$this->parent->addSQL( $this->create( $this->parent ) );
				xml_set_object( $parser, $this->parent );
				$this->destroy();
				break;
			default:
				
		}
	}
	
	/**
	* Re-initializes the query.
	*
	* @return boolean TRUE
	*/
	function newQuery() {
		$this->query = '';
		
		return TRUE;
	}
	
	/**
	* Discards the existing query.
	*
	* @return boolean TRUE
	*/
	function discardQuery() {
		unset( $this->query );
		
		return TRUE;
	}
	
	/** 
	* Appends a line to a query that is being built line by line
	*
	* @param string $data Line of SQL data or NULL to initialize a new query
	* @return string SQL query string.
	*/
	function buildQuery( $sql = NULL ) {
		if( !isset( $this->query ) ) {
			return FALSE;
		}
		
		if( empty( $sql ) ) {
			return FALSE;
		}
		
		if( !empty( $this->query ) ) {
			$this->query .= ' ';
		}
		
		$this->query .= trim( $sql );
		
		return $this->query;
	}
	
	/**
	* Adds a completed query to the query list
	*
	* @return string	SQL of added query
	*/
	function addQuery() {
		if( !isset( $this->query ) ) {
			return FALSE;
		}
		
		$this->queries[] = $this->query;
		$return = $this->query;
		
		unset( $this->query );
		
		return $return;
	}
	
	/**
	* Creates and returns the current query set
	*
	* @param object $xmls adoSchema object
	* @return array Query set
	*/
	function create( &$xmls ) {
		foreach( $this->queries as $id => $query ) {
			switch( $this->prefixMethod ) {
				case 'AUTO':
					// Enable auto prefix replacement
					
					// Process object prefix.
					// Evaluate SQL statements to prepend prefix to objects
					$query = $this->prefixQuery( '/^\s*((?is)INSERT\s+(INTO\s+)?)((\w+\s*,?\s*)+)(\s.*$)/', $query );
					$query = $this->prefixQuery( '/^\s*((?is)UPDATE\s+(FROM\s+)?)((\w+\s*,?\s*)+)(\s.*$)/', $query );
					$query = $this->prefixQuery( '/^\s*((?is)DELETE\s+(FROM\s+)?)((\w+\s*,?\s*)+)(\s.*$)/', $query );
					
					// SELECT statements aren't working yet
					#$data = preg_replace( '/(?ias)(^\s*SELECT\s+.*\s+FROM)\s+(\W\s*,?\s*)+((?i)\s+WHERE.*$)/', "\1 $prefix\2 \3", $data );
					
				case 'MANUAL':
					// If prefixKey is set and has a value then we use it to override the default constant XMLS_PREFIX.
					// If prefixKey is not set, we use the default constant XMLS_PREFIX
					if( isset( $this->prefixKey ) AND( $this->prefixKey !== '' ) ) {
						// Enable prefix override
						$query = str_replace( $this->prefixKey, $xmls->objectPrefix, $query );
					} else {
						// Use default replacement
						$query = str_replace( XMLS_PREFIX , $xmls->objectPrefix, $query );
					}
			}
			
			$this->queries[$id] = trim( $query );
		}
		
		// Return the query set array
		return $this->queries;
	}
	
	/**
	* Rebuilds the query with the prefix attached to any objects
	*
	* @param string $regex Regex used to add prefix
	* @param string $query SQL query string
	* @param string $prefix Prefix to be appended to tables, indices, etc.
	* @return string Prefixed SQL query string.
	*/
	function prefixQuery( $regex, $query, $prefix = NULL ) {
		if( !isset( $prefix ) ) {
			return $query;
		}
		
		if( preg_match( $regex, $query, $match ) ) {
			$preamble = $match[1];
			$postamble = $match[5];
			$objectList = explode( ',', $match[3] );
			// $prefix = $prefix . '_';
			
			$prefixedList = '';
			
			foreach( $objectList as $object ) {
				if( $prefixedList !== '' ) {
					$prefixedList .= ', ';
				}
				
				$prefixedList .= $prefix . trim( $object );
			}
			
			$query = $preamble . ' ' . $prefixedList . ' ' . $postamble;
		}
		
		return $query;
	}
}

/**
* Loads and parses an XML file, creating an array of "ready-to-run" SQL statements
* 
* This class is used to load and parse the XML file, to create an array of SQL statements
* that can be used to build a database, and to build the database using the SQL array.
*
* @tutorial getting_started.pkg
*
* @author Richard Tango-Lowy & Dan Cech
* @version $Revision: 1.2 $
*
* @package axmls
*/
class adoSchema {
	
	/**
	* @var array	Array containing SQL queries to generate all objects
	* @access private
	*/
	var $sqlArray;
	
	/**
	* @var object	ADOdb connection object
	* @access private
	*/
	var $db;
	
	/**
	* @var object	ADOdb Data Dictionary
	* @access private
	*/
	var $dict;
	
	/**
	* @var string Current XML element
	* @access private
	*/
	var $currentElement = '';
	
	/**
	* @var string If set (to 'ALTER' or 'REPLACE'), upgrade an existing database
	* @access private
	*/
	var $upgrade = '';
	
	/**
	* @var string Optional object prefix
	* @access private
	*/
	var $objectPrefix = '';
	
	/**
	* @var long	Original Magic Quotes Runtime value
	* @access private
	*/
	var $mgq;
	
	/**
	* @var long	System debug
	* @access private
	*/
	var $debug;
	
	/**
	* @var string Regular expression to find schema version
	* @access private
	*/
	var $versionRegex = '/<schema.*?( version="([^"]*)")?.*?>/';
	
	/**
	* @var string Current schema version
	* @access private
	*/
	var $schemaVersion;
	
	/**
	* @var int	Success of last Schema execution
	*/
	var $success;
	
	/**
	* @var bool	Execute SQL inline as it is generated
	*/
	var $executeInline;
	
	/**
	* @var bool	Continue SQL execution if errors occur
	*/
	var $continueOnError;
	
	/**
	* Creates an adoSchema object
	*
	* Creating an adoSchema object is the first step in processing an XML schema.
	* The only parameter is an ADOdb database connection object, which must already
	* have been created.
	*
	* @param object $db ADOdb database connection object.
	*/
	function adoSchema( &$db ) {
		// Initialize the environment
		$this->mgq = get_magic_quotes_runtime();
		set_magic_quotes_runtime(0);
		
		$this->debug = $this->db->debug;
		$this->db =& $db;
		$this->dict = NewDataDictionary( $this->db );
		$this->sqlArray = array();
		$this->schemaVersion = XMLS_SCHEMA_VERSION;
		$this->executeInline( XMLS_EXECUTE_INLINE );
		$this->continueOnError( XMLS_CONTINUE_ON_ERROR );
		$this->setUpgradeMethod();
	}
	
	/**
	* Sets the method to be used for upgrading an existing database
	*
	* Use this method to specify how existing database objects should be upgraded.
	* The method option can be set to ALTER, REPLACE, BEST, or NONE. ALTER attempts to
	* alter each database object directly, REPLACE attempts to rebuild each object
	* from scratch, BEST attempts to determine the best upgrade method for each
	* object, and NONE disables upgrading.
	*
	* This method is not yet used by AXMLS, but exists for backward compatibility.
	* The ALTER method is automatically assumed when the adoSchema object is
	* instantiated; other upgrade methods are not currently supported.
	*
	* @param string $method Upgrade method (ALTER|REPLACE|BEST|NONE)
	* @returns string Upgrade method used
	*/
	function SetUpgradeMethod( $method = '' ) {
		if( !is_string( $method ) ) {
			return FALSE;
		}
		
		$method = strtoupper( $method );
		
		// Handle the upgrade methods
		switch( $method ) {
			case 'ALTER':
				$this->upgrade = $method;
				break;
			case 'REPLACE':
				$this->upgrade = $method;
				break;
			case 'BEST':
				$this->upgrade = 'ALTER';
				break;
			case 'NONE':
				$this->upgrade = 'NONE';
				break;
			default:
				// Use default if no legitimate method is passed.
				$this->upgrade = XMLS_DEFAULT_UPGRADE_METHOD;
		}
		
		return $this->upgrade;
	}
	
	/**
	* Enables/disables inline SQL execution.
	*
	* Call this method to enable or disable inline execution of the schema. If the mode is set to TRUE (inline execution),
	* AXMLS applies the SQL to the database immediately as each schema entity is parsed. If the mode
	* is set to FALSE (post execution), AXMLS parses the entire schema and you will need to call adoSchema::ExecuteSchema()
	* to apply the schema to the database.
	*
	* @param bool $mode execute
	* @return bool current execution mode
	*
	* @see ParseSchema(), ExecuteSchema()
	*/
	function ExecuteInline( $mode = NULL ) {
		if( is_bool( $mode ) ) {
			$this->executeInline = $mode;
		}
		
		return $this->executeInline;
	}
	
	/**
	* Enables/disables SQL continue on error.
	*
	* Call this method to enable or disable continuation of SQL execution if an error occurs.
	* If the mode is set to TRUE (continue), AXMLS will continue to apply SQL to the database, even if an error occurs.
	* If the mode is set to FALSE (halt), AXMLS will halt execution of generated sql if an error occurs, though parsing
	* of the schema will continue.
	*
	* @param bool $mode execute
	* @return bool current continueOnError mode
	*
	* @see addSQL(), ExecuteSchema()
	*/
	function ContinueOnError( $mode = NULL ) {
		if( is_bool( $mode ) ) {
			$this->continueOnError = $mode;
		}
		
		return $this->continueOnError;
	}
	
	/**
	* Loads an XML schema from a file and converts it to SQL.
	*
	* Call this method to load the specified schema (see the DTD for the proper format) from
	* the filesystem and generate the SQL necessary to create the database described. 
	* @see ParseSchemaString()
	*
	* @param string $file Name of XML schema file.
	* @return array Array of SQL queries, ready to execute
	*/
	function ParseSchema( $filename ) {
		return $this->ParseSchemaString( $this->ConvertSchemaFile ( $filename ) );
	}
	
	/**
	* Loads an XML schema from a file and converts it to SQL.
	*
	* Call this method to load the specified schema from a file (see the DTD for the proper format) 
	* and generate the SQL necessary to create the database described by the schema.
	*
	* @param string $file Name of XML schema file.
	* @return array Array of SQL queries, ready to execute.
	*
	* @deprecated Replaced by adoSchema::ParseSchema() and adoSchema::ParseSchemaString()
	* @see ParseSchema(), ParseSchemaString()
	*/
	function ParseSchemaFile( $filename ) {
		// Open the file
		if( !($fp = fopen( $filename, 'r' )) ) {
			// die( 'Unable to open file' );
			return FALSE;
		}
		
		// do version detection here
		if( $this->SchemaFileVersion( $filename ) != $this->schemaVersion ) {
			return FALSE;
		}
		
		$xmlParser = $this->create_parser();
		
		// Process the file
		while( $data = fread( $fp, 4096 ) ) {
			if( !xml_parse( $xmlParser, $data, feof( $fp ) ) ) {
				die( sprintf(
					"XML error: %s at line %d",
					xml_error_string( xml_get_error_code( $xmlParser) ),
					xml_get_current_line_number( $xmlParser)
				) );
			}
		}
		
		xml_parser_free( $xmlParser );
		
		return $this->sqlArray;
	}
	
	/**
	* Converts an XML schema string to SQL.
	*
	* Call this method to parse a string containing an XML schema (see the DTD for the proper format)
	* and generate the SQL necessary to create the database described by the schema. 
	* @see ParseSchema()
	*
	* @param string $xmlstring XML schema string.
	* @return array Array of SQL queries, ready to execute.
	*/
	function ParseSchemaString( $xmlstring ) {
		if( !is_string( $xmlstring ) OR empty( $xmlstring ) ) {
			return FALSE;
		}
		
		// do version detection here
		if( $this->SchemaStringVersion( $xmlstring ) != $this->schemaVersion ) {
			return FALSE;
		}
		
		$xmlParser = $this->create_parser();
		
		$this->success = 2;
		
		if( !xml_parse( $xmlParser, $xmlstring, TRUE ) ) {
			die( sprintf(
				"XML error: %s at line %d",
				xml_error_string( xml_get_error_code( $xmlParser) ),
				xml_get_current_line_number( $xmlParser)
			) );
		}
		
		xml_parser_free( $xmlParser );
		return $this->sqlArray;
	}
	
	/**
	* Applies the current XML schema to the database (post execution).
	*
	* Call this method to apply the current schema (generally created by calling 
	* ParseSchema() or ParseSchemaString() ) to the database (creating the tables, indexes, 
	* and executing other SQL specified in the schema) after parsing.
	* @see ParseSchema(), ParseSchemaString(), ExecuteInline()
	*
	* @param array $sqlArray Array of SQL statements that will be applied rather than
	*		the current schema.
	* @param boolean $continueOnErr Continue to apply the schema even if an error occurs.
	* @returns integer 0 if failure, 1 if errors, 2 if successful.
	*/
	function ExecuteSchema( $sqlArray = NULL, $continueOnErr =  NULL ) {
		if( !is_bool( $continueOnErr ) ) {
			$continueOnErr = $this->ContinueOnError();
		}
		
		if( !isset( $sqlArray ) ) {
			$sqlArray = $this->sqlArray;
		}
		
		if( !is_array( $sqlArray ) ) {
			$this->success = 0;
		} else {
			$this->success = $this->dict->ExecuteSQLArray( $sqlArray, $continueOnErr );
		}
		
		return $this->success;
	}
	
	/**
	* Returns the current SQL array. 
	*
	* Call this method to fetch the array of SQL queries resulting from 
	* ParseSchema() or ParseSchemaString(). 
	*
	* @param string $format Format: HTML, TEXT, or NONE (PHP array)
	* @return array Array of SQL statements or FALSE if an error occurs
	*/
	function PrintSQL( $format = 'NONE' ) {
		return $this->getSQL( $format, $sqlArray );
	}
	
	/**
	* Saves the current SQL array to the local filesystem as a list of SQL queries.
	*
	* Call this method to save the array of SQL queries (generally resulting from a
	* parsed XML schema) to the filesystem.
	*
	* @param string $filename Path and name where the file should be saved.
	* @return boolean TRUE if save is successful, else FALSE. 
	*/
	function SaveSQL( $filename = './schema.sql' ) {
		
		if( !isset( $sqlArray ) ) {
			$sqlArray = $this->sqlArray;
		}
		if( !isset( $sqlArray ) ) {
			return FALSE;
		}
		
		$fp = fopen( $filename, "w" );
		
		foreach( $sqlArray as $key => $query ) {
			fwrite( $fp, $query . ";\n" );
		}
		fclose( $fp );
	}
	
	/**
	* Create an xml parser
	*
	* @return object PHP XML parser object
	*
	* @access private
	*/
	function &create_parser() {
		// Create the parser
		$xmlParser = xml_parser_create();
		xml_set_object( $xmlParser, $this );
		
		// Initialize the XML callback functions
		xml_set_element_handler( $xmlParser, '_tag_open', '_tag_close' );
		xml_set_character_data_handler( $xmlParser, '_tag_cdata' );
		
		return $xmlParser;
	}
	
	/**
	* XML Callback to process start elements
	*
	* @access private
	*/
	function _tag_open( &$parser, $tag, $attributes ) {
		switch( strtoupper( $tag ) ) {
			case 'TABLE':
				$this->obj = new dbTable( $this, $attributes );
				xml_set_object( $parser, $this->obj );
				break;
			case 'SQL':
				if( !isset( $attributes['PLATFORM'] ) OR $this->supportedPlatform( $attributes['PLATFORM'] ) ) {
					$this->obj = new dbQuerySet( $this, $attributes );
					xml_set_object( $parser, $this->obj );
				}
				break;
			default:
				// print_r( array( $tag, $attributes ) );
		}
		
	}
	
	/**
	* XML Callback to process CDATA elements
	*
	* @access private
	*/
	function _tag_cdata( &$parser, $cdata ) {
	}
	
	/**
	* XML Callback to process end elements
	*
	* @access private
	* @internal
	*/
	function _tag_close( &$parser, $tag ) {
		
	}
	
	/**
	* Converts an XML schema string to the specified DTD version.
	*
	* Call this method to convert a string containing an XML schema to a different AXMLS
	* DTD version. For instance, to convert a schema created for an pre-1.0 version for 
	* AXMLS (DTD version 0.1) to a newer version of the DTD (e.g. 0.2). If no DTD version 
	* parameter is specified, the schema will be converted to the current DTD version. 
	* If the newFile parameter is provided, the converted schema will be written to the specified
	* file.
	* @see ConvertSchemaFile()
	*
	* @param string $schema String containing XML schema that will be converted.
	* @param string $newVersion DTD version to convert to.
	* @param string $newFile File name of (converted) output file.
	* @return string Converted XML schema or FALSE if an error occurs.
	*/
	function ConvertSchemaString( $schema, $newVersion = NULL, $newFile = NULL ) {
		
		// grab current version
		if( !( $version = $this->SchemaStringVersion( $schema ) ) ) {
			return FALSE;
		}
		
		if( !isset ($newVersion) ) {
			$newVersion = $this->schemaVersion;
		}
		
		if( $version == $newVersion ) {
			$result = $schema;
		} else {
			// Fail if XSLT extension is not available
			if( ! function_exists( 'xslt_create' ) ) {
				return FALSE;
			}
			
			$xsl_file = dirname( __FILE__ ) . '/xsl/convert-' . $version . '-' . $newVersion . '.xsl';
			
			// look for xsl
			if( !is_readable( $xsl_file ) ) {
				return FALSE;
			}
			
			$arguments = array (
				'/_xml' => $schema,
				'/_xsl' => file_get_contents ($xsl_file)
			);
			
			// create an XSLT processor
			$xh = xslt_create ();
			
			// set error handler
			xslt_set_error_handler ($xh, array (&$this, 'xslt_error_handler'));
			
			// process the schema
			$result = xslt_process ($xh, 'arg:/_xml', 'arg:/_xsl', NULL, $arguments); 
			
			xslt_free ($xh);
		}
		
		if( is_string ($newFile) AND ( $fp = fopen( $newFile, 'w' ) ) ) {
			fwrite ($fp, $result);
			fclose ($fp);
		}
		
		return $result;
	}
	
	/**
	* Converts an XML schema file to the specified DTD version.
	*
	* Call this method to convert the specified XML schema file to a different AXMLS
	* DTD version. For instance, to convert a schema created for an pre-1.0 version for 
	* AXMLS (DTD version 0.1) to a newer version of the DTD (e.g. 0.2). If no DTD version 
	* parameter is specified, the schema will be converted to the current DTD version. 
	* If the newFile parameter is provided, the converted schema will be written to the specified
	* file.
	* @see ConvertSchemaString()
	*
	* @param string $filename Name of XML schema file that will be converted.
	* @param string $newVersion DTD version to convert to.
	* @param string $newFile File name of (converted) output file.
	* @return string Converted XML schema or FALSE if an error occurs.
	*/
	function ConvertSchemaFile( $filename, $newVersion = NULL, $newFile = NULL ) {
		
		// grab current version
		if( !( $version = $this->SchemaFileVersion( $filename ) ) ) {
			return FALSE;
		}
		
		if( !isset ($newVersion) ) {
			$newVersion = $this->schemaVersion;
		}
		
		if( $version == $newVersion ) {
			$result = file_get_contents( $filename );
			
			// remove unicode BOM if present
			if( substr( $result, 0, 3 ) == sprintf( '%c%c%c', 239, 187, 191 ) ) {
				$result = substr( $result, 3 );
			}
		} else {
			// Fail if XSLT extension is not available
			if( ! function_exists( 'xslt_create' ) ) {
				return FALSE;
			}
			
			$xsl_file = dirname( __FILE__ ) . '/xsl/convert-' . $version . '-' . $newVersion . '.xsl';
			
			// look for xsl
			if( !is_readable( $xsl_file ) ) {
				return FALSE;
			}
			
			$arguments = array (
				'/_xml' => file_get_contents ($filename),
				'/_xsl' => file_get_contents ($xsl_file)
			);
			
			// create an XSLT processor
			$xh = xslt_create ();
			
			// set error handler
			xslt_set_error_handler ($xh, array (&$this, 'xslt_error_handler'));
			
			// process the schema
			$result = xslt_process ($xh, 'arg:/_xml', 'arg:/_xsl', NULL, $arguments); 
			
			xslt_free ($xh);
		}
		
		if( is_string ($newFile) AND ( $fp = fopen( $newFile, 'w' ) ) ) {
			fwrite ($fp, $result);
			fclose ($fp);
		}
		
		return $result;
	}
	
	/**
	* Processes XSLT transformation errors
	*
	* @param object $parser XML parser object
	* @param integer $errno Error number
	* @param integer $level Error level
	* @param array $fields Error information fields
	*
	* @access private
	*/
	function xslt_error_handler( $parser, $errno, $level, $fields ) {
		if( is_array( $fields ) ) {
			$msg = array(
				'Message Type' => ucfirst( $fields['msgtype'] ),
				'Message Code' => $fields['code'],
				'Message' => $fields['msg'],
				'Error Number' => $errno,
				'Level' => $level
			);
			
			switch( $fields['URI'] ) {
				case 'arg:/_xml':
					$msg['Input'] = 'XML';
					break;
				case 'arg:/_xsl':
					$msg['Input'] = 'XSL';
					break;
				default:
					$msg['Input'] = $fields['URI'];
			}
			
			$msg['Line'] = $fields['line'];
		} else {
			$msg = array(
				'Message Type' => 'Error',
				'Error Number' => $errno,
				'Level' => $level,
				'Fields' => var_export( $fields, TRUE )
			);
		}
		
		$error_details = $msg['Message Type'] . ' in XSLT Transformation' . "\n"
					   . '<table>' . "\n";
		
		foreach( $msg as $label => $details ) {
			$error_details .= '<tr><td><b>' . $label . ': </b></td><td>' . htmlentities( $details ) . '</td></tr>' . "\n";
		}
		
		$error_details .= '</table>';
		
		trigger_error( $error_details, E_USER_ERROR );
	}
	
	/**
	* Returns the AXMLS Schema Version of the requested XML schema file.
	*
	* Call this method to obtain the AXMLS DTD version of the requested XML schema file.
	* @see SchemaStringVersion()
	*
	* @param string $filename AXMLS schema file
	* @return string Schema version number or FALSE on error
	*/
	function SchemaFileVersion( $filename ) {
		// Open the file
		if( !($fp = fopen( $filename, 'r' )) ) {
			// die( 'Unable to open file' );
			return FALSE;
		}
		
		// Process the file
		while( $data = fread( $fp, 4096 ) ) {
			if( preg_match( $this->versionRegex, $data, $matches ) ) {
				return !empty( $matches[2] ) ? $matches[2] : XMLS_DEFAULT_SCHEMA_VERSION;
			}
		}
		
		return FALSE;
	}
	
	/**
	* Returns the AXMLS Schema Version of the provided XML schema string.
	*
	* Call this method to obtain the AXMLS DTD version of the provided XML schema string.
	* @see SchemaFileVersion()
	*
	* @param string $xmlstring XML schema string
	* @return string Schema version number or FALSE on error
	*/
	function SchemaStringVersion( $xmlstring ) {
		if( !is_string( $xmlstring ) OR empty( $xmlstring ) ) {
			return FALSE;
		}
		
		if( preg_match( $this->versionRegex, $xmlstring, $matches ) ) {
			return !empty( $matches[2] ) ? $matches[2] : XMLS_DEFAULT_SCHEMA_VERSION;
		}
		
		return FALSE;
	}
	
	/**
	* Extracts an XML schema from an existing database.
	*
	* Call this method to create an XML schema string from an existing database.
	* If the data parameter is set to TRUE, AXMLS will include the data from the database
	* in the schema. 
	*
	* @param boolean $data Include data in schema dump
	* @return string Generated XML schema
	*/
	function ExtractSchema( $data = FALSE ) {
		$old_mode = $this->db->SetFetchMode( ADODB_FETCH_NUM );
		
		$schema = '<?xml version="1.0"?>' . "\n"
				. '<schema version="' . $this->schemaVersion . '">' . "\n";
		
		if( is_array( $tables = $this->db->MetaTables( 'TABLES' ) ) ) {
			foreach( $tables as $table ) {
				$schema .= '	<table name="' . $table . '">' . "\n";
				
				// grab details from database
				$rs = $this->db->Execute( 'SELECT * FROM ' . $table . ' WHERE -1' );
				$fields = $this->db->MetaColumns( $table );
				$indexes = $this->db->MetaIndexes( $table );
				
				if( is_array( $fields ) ) {
					foreach( $fields as $details ) {
						$extra = '';
						$content = array();
						
						if( $details->max_length > 0 ) {
							$extra .= ' size="' . $details->max_length . '"';
						}
						
						if( $details->primary_key ) {
							$content[] = '<PRIMARY/>';
						} elseif( $details->not_null ) {
							$content[] = '<NOTNULL/>';
						}
						
						if( $details->has_default ) {
							$content[] = '<DEFAULT value="' . $details->default_value . '"/>';
						}
						
						if( $details->auto_increment ) {
							$content[] = '<AUTOINCREMENT/>';
						}
						
						// this stops the creation of 'R' columns,
						// AUTOINCREMENT is used to create auto columns
						$details->primary_key = 0;
						$type = $rs->MetaType( $details );
						
						$schema .= '		<field name="' . $details->name . '" type="' . $type . '"' . $extra . '>';
						
						if( !empty( $content ) ) {
							$schema .= "\n			" . implode( "\n			", $content ) . "\n		";
						}
						
						$schema .= '</field>' . "\n";
					}
				}
				
				if( is_array( $indexes ) ) {
					foreach( $indexes as $index => $details ) {
						$schema .= '		<index name="' . $index . '">' . "\n";
						
						if( $details['unique'] ) {
							$schema .= '			<UNIQUE/>' . "\n";
						}
						
						foreach( $details['columns'] as $column ) {
							$schema .= '			<col>' . $column . '</col>' . "\n";
						}
						
						$schema .= '		</index>' . "\n";
					}
				}
				
				if( $data ) {
					$rs = $this->db->Execute( 'SELECT * FROM ' . $table );
					
					if( is_object( $rs ) ) {
						$schema .= '		<data>' . "\n";
						
						while( $row = $rs->FetchRow() ) {
							$schema .= '			<row>';
							foreach ($row as $field) {
								$schema .= '<f>' . htmlentities($field, ENT_COMPAT) . '</f>';
							}
							$schema .= '</row>' . "\n";
						}
						
						$schema .= '		</data>' . "\n";
					}
				}
				
				$schema .= '	</table>' . "\n";
			}
		}
		
		$this->db->SetFetchMode( $old_mode );
		
		$schema .= '</schema>';
		return $schema;
	}
	
	/**
	* Sets a prefix for database objects
	*
	* Call this method to set a standard prefix that will be prepended to all database tables 
	* and indices when the schema is parsed. Calling setPrefix with no arguments clears the prefix.
	*
	* @param string $prefix Prefix that will be prepended.
	* @param boolean $underscore If TRUE, automatically append an underscore character to the prefix.
	* @return boolean TRUE if successful, else FALSE
	*/
	function SetPrefix( $prefix = '', $underscore = TRUE ) {
		switch( TRUE ) {
			// clear prefix
			case empty( $prefix ):
				logMsg( 'Cleared prefix' );
				$this->objectPrefix = '';
				return TRUE;
			// prefix too long
			case strlen( $prefix ) > XMLS_PREFIX_MAXLEN:
			// prefix contains invalid characters
			case !preg_match( '/^[a-z][a-z0-9]+$/i', $prefix ):
				logMsg( 'Invalid prefix: ' . $prefix );
				return FALSE;
		}
		
		if( $underscore AND substr( $prefix, -1 ) != '_' ) {
			$prefix .= '_';
		}
		
		// prefix valid
		logMsg( 'Set prefix: ' . $prefix );
		$this->objectPrefix = $prefix;
		return TRUE;
	}
	
	/**
	* Returns an object name with the current prefix prepended.
	*
	* @param string	$name Name
	* @return string	Prefixed name
	*
	* @access private
	*/
	function prefix( $name = '' ) {
		// if prefix is set
		if( !empty( $this->objectPrefix ) ) {
			// Prepend the object prefix to the table name
			// prepend after quote if used
			return preg_replace( '/^(`?)(.+)$/', '$1' . $this->objectPrefix . '$2', $name );
		}
		
		// No prefix set. Use name provided.
		return $name;
	}
	
	/**
	* Checks if element references a specific platform
	*
	* @param string $platform Requested platform
	* @returns boolean TRUE if platform check succeeds
	*
	* @access private
	*/
	function supportedPlatform( $platform = NULL ) {
		$regex = '/^(\w*\|)*' . $this->db->databaseType . '(\|\w*)*$/';
		
		if( !isset( $platform ) OR preg_match( $regex, $platform ) ) {
			logMsg( "Platform $platform is supported" );
			return TRUE;
		} else {
			logMsg( "Platform $platform is NOT supported" );
			return FALSE;
		}
	}
	
	/**
	* Clears the array of generated SQL.
	*
	* @access private
	*/
	function clearSQL() {
		$this->sqlArray = array();
	}
	
	/**
	* Adds SQL into the SQL array.
	*
	* @param mixed $sql SQL to Add
	* @return boolean TRUE if successful, else FALSE.
	*
	* @access private
	*/	
	function addSQL( $sql = NULL ) {
		if( is_array( $sql ) ) {
			foreach( $sql as $line ) {
				$this->addSQL( $line );
			}
			
			return TRUE;
		}
		
		if( is_string( $sql ) ) {
			$this->sqlArray[] = $sql;
			
			// if executeInline is enabled, and either no errors have occurred or continueOnError is enabled, execute SQL.
			if( $this->ExecuteInline() && ( $this->success == 2 || $this->ContinueOnError() ) ) {
				$saved = $this->db->debug;
				$this->db->debug = $this->debug;
				$ok = $this->db->Execute( $sql );
				$this->db->debug = $saved;
				
				if( !$ok ) {
					if( $this->debug ) {
						ADOConnection::outp( $this->db->ErrorMsg() );
					}
					
					$this->success = 1;
				}
			}
			
			return TRUE;
		}
		
		return FALSE;
	}
	
	/**
	* Gets the SQL array in the specified format.
	*
	* @param string $format Format
	* @return mixed SQL
	*	
	* @access private
	*/
	function getSQL( $format = NULL, $sqlArray = NULL ) {
		if( !is_array( $sqlArray ) ) {
			$sqlArray = $this->sqlArray;
		}
		
		if( !is_array( $sqlArray ) ) {
			return FALSE;
		}
		
		switch( strtolower( $format ) ) {
			case 'string':
			case 'text':
				return !empty( $sqlArray ) ? implode( ";\n\n", $sqlArray ) . ';' : '';
			case'html':
				return !empty( $sqlArray ) ? nl2br( htmlentities( implode( ";\n\n", $sqlArray ) . ';' ) ) : '';
		}
		
		return $this->sqlArray;
	}
	
	/**
	* Destroys an adoSchema object.
	*
	* Call this method to clean up after an adoSchema object that is no longer in use.
	* @deprecated adoSchema now cleans up automatically.
	*/
	function Destroy() {
		set_magic_quotes_runtime( $this->mgq );
		unset( $this );
	}
}

/**
* Message logging function
*
* @access private
*/
function logMsg( $msg, $title = NULL ) {
	if( XMLS_DEBUG ) {
		echo '<pre>';
		
		if( isset( $title ) ) {
			echo '<h3>' . htmlentities( $title ) . '</h3>';
		}
		
		if( is_object( $this ) ) {
			echo '[' . get_class( $this ) . '] ';
		}
		
		print_r( $msg );
		
		echo '</pre>';
	}
}
?>
