/**
 * Copyright (c) 2004, www.pdfbox.org
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 *    this list of conditions and the following disclaimer in the documentation
 *    and/or other materials provided with the distribution.
 * 3. Neither the name of pdfbox; nor the names of its
 *    contributors may be used to endorse or promote products derived from this
 *    software without specific prior written permission.
 *
 * 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 WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * http://www.pdfbox.org
 *
 */
package org.pdfbox.pdfwriter;

import java.io.IOException;
import java.io.OutputStream;

import java.util.Iterator;
import java.util.List;

import org.pdfbox.cos.COSArray;
import org.pdfbox.cos.COSBase;
import org.pdfbox.cos.COSBoolean;
import org.pdfbox.cos.COSDictionary;
import org.pdfbox.cos.COSFloat;
import org.pdfbox.cos.COSInteger;
import org.pdfbox.cos.COSName;
import org.pdfbox.cos.COSString;

import org.pdfbox.util.ImageParameters;
import org.pdfbox.util.PDFOperator;

/**
 * A class that will take a list of tokens and write out a stream with them.
 * 
 * @author Ben Litchfield (ben@benlitchfield.com)
 * @version $Revision: 1.7 $
 */
public class ContentStreamWriter
{
    private OutputStream output;
    /**
     * space character.
     */
    public static final byte[] SPACE = new byte[] { 32 };
    
    /**
     * standard line separator on this platform.
     */
    public static final byte[] EOL = System.getProperty("line.separator").getBytes();
    
    /**
     * This will create a new content stream writer.
     * 
     * @param out The stream to write the data to. 
     */
    public ContentStreamWriter( OutputStream out )
    {
        output = out;
    }
    
    /**
     * This will write out the list of tokens to the stream.
     *  
     * @param tokens The tokens to write to the stream.
     * @param start The start index into the list of tokens.
     * @param end The end index into the list of tokens.
     * @throws IOException If there is an error writing to the stream.
     */
    public void writeTokens( List tokens, int start, int end ) throws IOException
    {
        for( int i=start; i<end; i++ )
        {
            Object o = tokens.get( i );
            writeObject( o );
            //write a space between each object.
            output.write( 32 );
        }
        output.flush();
    }
    
    private void writeObject( Object o ) throws IOException
    {
        if( o instanceof COSString )
        {
            ((COSString)o).writePDF( output );
        }
        else if( o instanceof COSFloat )
        {
            ((COSFloat)o).writePDF( output );
        }
        else if( o instanceof COSInteger )
        {
            ((COSInteger)o).writePDF( output );
        }
        else if( o instanceof COSBoolean )
        {
            ((COSBoolean)o).writePDF( output );
        }
        else if( o instanceof COSName )
        {
            ((COSName)o).writePDF( output );
        }
        else if( o instanceof COSArray )
        {
            COSArray array = (COSArray)o;
            output.write(COSWriter.ARRAY_OPEN);
            for( int i=0; i<array.size(); i++ )
            {
                writeObject( array.get( i ) );
                output.write( SPACE );
            }
            
            output.write( COSWriter.ARRAY_CLOSE );
        }
        else if( o instanceof COSDictionary ) 
        {
            COSDictionary obj = (COSDictionary)o;
            output.write( COSWriter.DICT_OPEN );
            for (Iterator i = obj.keyList().iterator(); i.hasNext();)
            {
                COSName name = (COSName) i.next();
                COSBase value = obj.getItem(name);
                if (value != null)
                {
                    writeObject( name );
                    output.write( SPACE );

                    writeObject( value );

                    output.write( SPACE );

                }
            }
            output.write( COSWriter.DICT_CLOSE );
            output.write( SPACE );
        }
        else if( o instanceof PDFOperator )
        {
            PDFOperator op = (PDFOperator)o;
            if( op.getOperation().equals( "BI" ) )
            {
                output.write( "BI".getBytes() );
                ImageParameters params = op.getImageParameters();
                COSDictionary dic = params.getDictionary();
                Iterator iter = dic.keyList().iterator();
                while( iter.hasNext() )
                {
                    COSName key = (COSName)iter.next();
                    Object value = dic.getDictionaryObject( key );
                    key.writePDF( output );
                    output.write( SPACE );
                    writeObject( value );
                    output.write( EOL );
                }
                output.write( "ID".getBytes() );
                output.write( EOL );
                output.write( op.getImageData() );
            }
            else
            {
                output.write( op.getOperation().getBytes() );
                output.write( EOL );
            }
        }
        else
        {
            throw new IOException( "Error:Unknown type in content stream:" + o );
        }
    }
    
    /**
     * This will write out the list of tokens to the stream.
     *  
     * @param tokens The tokens to write to the stream.
     * @throws IOException If there is an error writing to the stream.
     */
    public void writeTokens( List tokens ) throws IOException
    {
        writeTokens( tokens, 0, tokens.size() );
    }
}