// This Source Code is in the Public Domain per: http://unlicense.org
package org.litesoft.util.template;

import java.io.*;
import java.util.*;

import org.litesoft.commonfoundation.exceptions.*;

public abstract class AbstractReaderTC extends AbstractTC
{
    protected Reader mTemplate;

    public AbstractReaderTC( Reader pTemplate, Collection<TCsub> pSubstitutions )
    {
        super( pSubstitutions );
        mTemplate = pTemplate;
    }

    protected String blocksFromReaderReplace( Writer pWriter, String pReplaceNotFoundsWith )
            throws IOException
    {
        String zIn = readBlock();
        for ( String zNext = readBlock(); zNext.length() != 0; zNext = readBlock() )
        {
            zIn = processSubstitutionsFrom( zIn, pWriter, pReplaceNotFoundsWith, null ) + zNext;
        }
        zIn = processSubstitutionsFrom( zIn, pWriter, pReplaceNotFoundsWith, null );
        return zIn;
    }

    private String readBlock()
            throws IOException
    {
        char[] zChars = new char[4096];
        int zCntRead = mTemplate.read( zChars );
        return (zCntRead <= 0) ? "" : new String( zChars, 0, zCntRead );
    }

    @Override
    public void dispose()
    {
        super.dispose();
        if ( mTemplate != null )
        {
            try
            {
                mTemplate.close();
            }
            catch ( IOException e )
            {
                // Exception on Closing a Reader should not be fatal?
                new PersistenceException( "Unable to close Reader" ).printStackTrace(); // Logging would have been preferable, but do not want a Logger dependency
            }
            finally
            {
                mTemplate = null;
            }
        }
    }
}