/*
 * @(#)$Id: ModuleMergeState.java,v 1.2 2001/05/01 18:13:09 Bear 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.relax.core;

import com.sun.msv.util.StartTagInfo;
import com.sun.msv.grammar.Expression;
import com.sun.msv.grammar.relax.RELAXModule;
import com.sun.msv.reader.*;

/**
 * Used to parse module.
 * 
 * As stand-alone, this state is used to parse a module included by another module.
 * By a base class, this state is used to parse a "head" module.
 * 
 * This class checks consistency between targetNamespace attribute
 * and the namespace specified by its caller (grammar/module).
 * 
 * @author <a href="mailto:kohsuke.kawaguchi@eng.sun.com">Kohsuke KAWAGUCHI</a>
 */
public class ModuleMergeState extends DivInModuleState
{
	protected ModuleMergeState( String expectedTargetNamespace )
	{
		this.expectedTargetNamespace = expectedTargetNamespace;
	}
	
	/** expected targetNamespace for this module.
	 * 
	 * null indicates that module must have targetNamespace attribute.
	 * 
	 * <p>
	 * If RELAX module has 'targetNamespace' attribute, then its value
	 * must be equal to this value, or this value must be null.
	 * 
	 * <p>
	 * If RELAX module doesn't have the attribute, then this value is
	 * used as the target namespace. If this value is null, then it is
	 * an error.
	 */
	protected final String expectedTargetNamespace;

	/**
	 * computed targetNamespace.
	 * 
	 * actual target namespace depends on expected target namespace
	 * and module. this field is set in startSelf method.
	 */
	protected String targetNamespace;
	
	protected void startSelf()
	{
		super.startSelf();
		
		{// check relaxCoreVersion
			final String coreVersion = startTag.getAttribute("relaxCoreVersion");
			if( coreVersion==null )
				reader.reportWarning( reader.ERR_MISSING_ATTRIBUTE, "module", "relaxCoreVersion" );
			else
			if(!"1.0".equals(coreVersion))
				reader.reportWarning( RELAXCoreReader.WRN_ILLEGAL_RELAXCORE_VERSION, coreVersion );
		}
		
		targetNamespace = startTag.getAttribute("targetNamespace");
		
		if(targetNamespace!=null)
		{
			// check accordance with expected namespace
			if( expectedTargetNamespace!=null
			&&  !expectedTargetNamespace.equals(targetNamespace) )
			{// error
				reader.reportError( RELAXCoreReader.ERR_INCONSISTENT_TARGET_NAMESPACE,
									targetNamespace, expectedTargetNamespace );
				// recover by ignoring one specified in the module
				targetNamespace = expectedTargetNamespace;
			}
		}
		else
		{// no targetnamespace attribute is given.
			if( expectedTargetNamespace==null )
			{
				reader.reportError( RELAXCoreReader.ERR_MISSING_TARGET_NAMESPACE );
				targetNamespace = "";	// recover by assuming the default namespace
			}
			else
				targetNamespace = expectedTargetNamespace;
		}
	}
}