/*
 * @(#)$Id: SchemaIncludedState.java,v 1.11 2003/06/09 20:37:34 kk122374 Exp $
 *
 * Copyright 2001 Sun Microsystems, Inc. All Rights Reserved.
 * 
 * This software is the proprietary information of Sun Microsystems, Inc.  
 * Use is subject to license terms.
 * 
 */
package com.sun.msv.reader.xmlschema;

import java.util.Set;

import com.sun.msv.reader.IgnoreState;
import com.sun.msv.reader.State;
import com.sun.msv.util.StartTagInfo;

/**
 * used to parse &lt;schema&gt; element of included schema.
 * 
 * @author <a href="mailto:kohsuke.kawaguchi@eng.sun.com">Kohsuke KAWAGUCHI</a>
 */
public class SchemaIncludedState extends GlobalDeclState {
    
    /**
     * target namespace that the caller expects.
     * 
     * If this field is null, that indicates caller doesn't
     * expect particular target namespace.
     * 
     * If this field is non-null and schema element has a different
     * value as targetNamespace, then error will be reported.
     */
    protected String expectedTargetNamespace;
    
    protected SchemaIncludedState( String expectedTargetNamespace ) {
        this.expectedTargetNamespace = expectedTargetNamespace;
    }
    
    // these fields keep the previous values.
    private String previousElementFormDefault;
    private String previousAttributeFormDefault;
    private String previousFinalDefault;
    private String previousBlockDefault;
    private String previousChameleonTargetNamespace;
    
    /**
     * this flag is set to true to indicate all the contents of this element
     * will be skipped (due to the double inclusion).
     */
    private boolean ignoreContents = false;
    
    protected State createChildState( StartTagInfo tag ) {
        if( ignoreContents    )        return new IgnoreState();
        else                        return super.createChildState(tag);
    }

    
    protected void startSelf() {
        final XMLSchemaReader reader = (XMLSchemaReader)this.reader;
        super.startSelf();
        
        // back up the current values
        previousElementFormDefault = reader.elementFormDefault;
        previousAttributeFormDefault = reader.attributeFormDefault;
        previousFinalDefault = reader.finalDefault;
        previousBlockDefault = reader.blockDefault;
        previousChameleonTargetNamespace = reader.chameleonTargetNamespace;

        
        // the chameleonTargetNamespace is usually null, unless we are parsing 
        // a chameleon schema.
        reader.chameleonTargetNamespace = null;
        
        String targetNs = startTag.getAttribute("targetNamespace");
        if( targetNs==null ) {
            if( expectedTargetNamespace==null ) {
                // this is not an error. It just means that the target namespace is absent.
                // reader.reportError( reader.ERR_MISSING_ATTRIBUTE, "schema", "targetNamespace" );
                targetNs = "";    // recover by assuming "" namespace.
            }
            else {
                // this is a chameleon schema.
                targetNs = expectedTargetNamespace;
                reader.chameleonTargetNamespace = expectedTargetNamespace;
            }
        } else {
            if( expectedTargetNamespace!=null
            && !expectedTargetNamespace.equals(targetNs) )
                reader.reportError( XMLSchemaReader.ERR_INCONSISTENT_TARGETNAMESPACE, targetNs, expectedTargetNamespace );
                // recover by adopting the one specified in the schema.
        }

        onTargetNamespaceResolved(targetNs);

        // check double inclusion.
        Set s = (Set)reader.parsedFiles.get(targetNs);
        if(s==null)
            reader.parsedFiles.put( targetNs, s = new java.util.HashSet() );
        
        if( s.contains(this.location.getSystemId()) )
            // this file is already included. So skip processing it.
            ignoreContents = true;
        else
            s.add(this.location.getSystemId());

        // process other attributes.
        
        String form;
        form = startTag.getDefaultedAttribute("elementFormDefault","unqualified");
        if( form.equals("qualified") )
            reader.elementFormDefault = targetNs;
        else {
            reader.elementFormDefault = "";
            if( !form.equals("unqualified") )
                reader.reportError( XMLSchemaReader.ERR_BAD_ATTRIBUTE_VALUE, "elementFormDefault", form );
        }
        
        form = startTag.getDefaultedAttribute("attributeFormDefault","unqualified");
        if( form.equals("qualified") )
            reader.attributeFormDefault = targetNs;
        else {
            reader.attributeFormDefault = "";
            if( !form.equals("unqualified") )
                reader.reportError( XMLSchemaReader.ERR_BAD_ATTRIBUTE_VALUE, "attributeFormDefault", form );
        }
        
        reader.finalDefault = startTag.getAttribute("finalDefault");
        reader.blockDefault = startTag.getAttribute("blockDefault");
        
    }

    /** does something useful with determined target namespace. */
    protected void onTargetNamespaceResolved( String targetNs ) {
    }
    
    protected void endSelf() {
        final XMLSchemaReader reader = (XMLSchemaReader)this.reader;
        reader.elementFormDefault = previousElementFormDefault;
        reader.attributeFormDefault = previousAttributeFormDefault;
        reader.finalDefault = previousFinalDefault;
        reader.blockDefault = previousBlockDefault;
        reader.chameleonTargetNamespace = previousChameleonTargetNamespace;
        
        super.endSelf();
    }
}
