/**
 * $Id: $
 * $Date: $
 *
 */

package org.xmlsh.xproc.compiler;

import java.io.PrintWriter;

/*
 * Stores temporary streams of data so that preamble and body data
 * can be serialized together
 */
public class OutputContext 
{
	private		StringBuffer	mPreamble = new StringBuffer();
	private		StringBuffer	mBody= new StringBuffer();
	private		String			mStepPrefix = "xps";
	private		Input			mPrimaryInput = null;
	private 	OutputContext 	mParent = null;
	
	
	public OutputContext()
	{
		addPreambleLine("import module " + mStepPrefix + "=org.xmlsh.xproc.steps");
		
	}
	
	private OutputContext( OutputContext parent )
	{
		mParent = parent ;
		mPrimaryInput = parent.mPrimaryInput;
		
	}
	/*
	 * Writes a line to the preamble
	 */
	
	public void	addPreambleLine( String s ){
		mPreamble.append(s ).append('\n');
	}
	
	public void	addPreamble( String s ){
		mPreamble.append(s );
	}
	
	/*
	 * Write line to the body
	 */
	public void	addBodyLine(String s ){
		mBody.append(s ).append('\n');
	}


	public void addBody(String s) {
		mBody.append(s );
		
	}


	public void serialize(PrintWriter w) {
		w.print(mPreamble.toString());
		w.println();
		w.print(mBody.toString());
		w.println();
		
	}
	
	public String getStepPrefix(){
		return mStepPrefix;
	}

	/**
	 * @return the primaryInput
	 */
	public Input getPrimaryInput() {
		return mPrimaryInput;
	}

	/**
	 * @param primaryInput the primaryInput to set
	 */
	public void setPrimaryInput(Input primaryInput) {
		mPrimaryInput = primaryInput;
	}

	
	/*
	 * Push the context to a sub-contest
	 */
	OutputContext push() 
	{
		OutputContext c = new OutputContext(this);
		return c;
	}
	
	/*
	 * Pop the context to its parent
	 * Both preamble and body get appended to the body of the parent
	 */
	OutputContext pop()
	{
		mParent.addBody( mPreamble.toString() );
		mParent.addBody( mBody.toString() );
		return mParent ;
		
	}
	
	OutputContext getParent() { return mParent ; }
	
	boolean isDerivedInput(Input in) {
		if( mParent == null )
			return false ;
		if( mParent.mPrimaryInput == in)
			return true ;
		return false;
		
		
	}
	

}



//
//
//Copyright (C) 2008,2009 , David A. Lee.
//
//The contents of this file are subject to the "Simplified BSD License" (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.opensource.org/licenses/bsd-license.php 
//
//Software distributed under the License is distributed on an "AS IS" basis,
//WITHOUT WARRANTY OF ANY KIND, either express or implied.
//See the License for the specific language governing rights and limitations under the License.
//
//The Original Code is: all this file.
//
//The Initial Developer of the Original Code is David A. Lee
//
//Portions created by (your name) are Copyright (C) (your legal entity). All Rights Reserved.
//
//Contributor(s): none.
//