/*
 * Copyright 2004 The Apache Software Foundation.
 * 
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */ 

package org.apache.commons.betwixt.schema;

import java.beans.IntrospectionException;

import org.apache.commons.betwixt.BindingConfiguration;
import org.apache.commons.betwixt.ElementDescriptor;
import org.apache.commons.betwixt.IntrospectionConfiguration;
import org.apache.commons.betwixt.XMLBeanInfo;
import org.apache.commons.betwixt.XMLIntrospector;

/**
 * <p>Generates XML Schemas for Betwixt mappings.
 * 
 * </p><p>
 * The basic idea is that an object model for the schema will be created
 * and Betwixt can be used to output this to xml.
 * This should allow both SAX and text.
 * </p>
 * @author <a href='http://jakarta.apache.org/'>Jakarta Commons Team</a>
 * @version $Revision: 1.2 $
 */
public class SchemaTranscriber {
	
    public static final String W3C_SCHEMA_URI = "http://www.w3.org/2001/XMLSchema";
    public static final String W3C_SCHEMA_INSTANCE_URI= "http://www.w3.org/2001/XMLSchema-instance";
    
	/** Used to introspect beans in order to generate XML */
	private XMLIntrospector introspector = new XMLIntrospector();
    private TranscriptionConfiguration configuration = new TranscriptionConfiguration();
	
	public SchemaTranscriber() {}
	 
    /**
     * Gets the configuration for the XMLBeanInfo to XML schema transcription.
     * @return TranscriptionConfiguration, not null
     */
    public TranscriptionConfiguration getConfiguration() {
        return configuration;
    }
    
    /**
     * Sets the configuration for the XMLBeanInfo to XML schema transcription.
     * @param configuration TranscriptionConfiguration, not null
     */
    public void setConfiguration(TranscriptionConfiguration configuration) {
        this.configuration = configuration;
    }
    
	/**
	 * Gets the XMLIntrospector used to create XMLInfoBean's.
	 * @return XMLIntrospector used to create XMLInfoBean's used to generate schema, not null
	 */
	public XMLIntrospector getXMLIntrospector() {
		return introspector;
	}
	
	/**
	 * <p>Sets the XMLIntrospector used to create XMLInfoBeans.
     * </p></p>
     * <strong>Note:</strong> certain properties will be reconfigured so that 
     * the introspection will produce correct results.
     * </p>
	 * @param introspector XMLIntrospector used to create XMLInfoBean's used to generate schema, not null
	 */
	public void setXMLIntrospector(XMLIntrospector introspector) {
		this.introspector = introspector;
	}

	/**
	 * Generates an XML Schema model for the given class.
	 * @param clazz not null
	 * @return Schema model, not null
	 */
	public Schema generate(Class clazz) throws IntrospectionException {
        XMLBeanInfo beanInfo = introspector.introspect(clazz);
		return generate(beanInfo);
	}
	
	/**
	 * Generates an XML Schema model from the given XMLBeanInfo
	 * @param xmlBeanInfo not null
	 * @return Schema model, not null
	 */
	public Schema generate(XMLBeanInfo xmlBeanInfo) throws IntrospectionException {
       ElementDescriptor elementDescriptor = xmlBeanInfo.getElementDescriptor(); 
	   Schema schema = new Schema(introspector);
       schema.addGlobalElementType(configuration, elementDescriptor);
       return schema;
	}
    
    /**
     * <p>Gets an <code>IntrospectionConfiguration</code> that is suitable 
     * for introspecting {@link Schema}.
     * </p><p>
     * <strong>Note:</strong> A new instance is created each time this method is called.
     * It can therefore be safely be modified.
     * </p>
     * 
     * @return IntrospectionConfiguration, not null
     */
    public IntrospectionConfiguration createSchemaIntrospectionConfiguration() {
        IntrospectionConfiguration configuration = new IntrospectionConfiguration();
        configuration.getPrefixMapper().setPrefix(W3C_SCHEMA_URI, "xsd");
        configuration.getPrefixMapper().setPrefix(W3C_SCHEMA_INSTANCE_URI, "xsi");
        return configuration;
    }
    
    /**
     * <p>Gets a <code>BindingConfiguration</code> that is suitable for mapping {@link Schema}.
     * </p><p>
     * <strong>Note:</strong> A new instance is created each time this method is called.
     * It can therefore be safely be modified.
     * </p>
     * @return BindingConfiguration, not null
     */
    public BindingConfiguration createSchemaBindingConfiguration() {
        BindingConfiguration configuration = new BindingConfiguration();
        configuration.setMapIDs(false);
        return configuration;   
    }
}