/*
 * (c) Copyright 2009 Hewlett-Packard Development Company, LP
 * All rights reserved.
 * [See endLog of file]
 */

package riot.io;

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

import org.openjena.atlas.lib.Pool ;
import org.openjena.riot.tokens.Token ;
import riot.comms.End ;
import riot.comms.TokenComms ;
import riot.comms.TokenStreamEndpoint ;



/** Iterate until the endLog marker is seen.
 */

public class TokenInputSection implements TokenInputStream
{
    // Should be a TokenInputStream (interface)
    
    private boolean finished = false ;
    private final TokenInputStream tokens ;
    private List<Token> list = null ;
    private Pool<TokenStreamEndpoint> pool ;
    private End atEnd ;
    
    public TokenInputSection(TokenInputStream tokenInputStream, End atEnd)
    {
        this.tokens = tokenInputStream ;
        this.atEnd = atEnd ;
    }

    @Override
    public boolean hasNext()
    {
        if ( finished )
            return false ;
        if ( list != null )
            return true ;
        if ( ! tokens.hasNext() )
        {
            close() ;
            finished = true ;
            return false ;
        }
        
        list = tokens.next() ;
        if ( TokenComms.isEndSectionMarker(list) || TokenComms.isEndStreamMarker(list)) 
        {
            close() ;
            finished = true ;
            return false ;
        }
        // It's not the endLog of a section. 
        return true ;
    }

    @Override
    public List<Token> next()
    {
        if ( ! hasNext() )
            throw new NoSuchElementException() ;
        List<Token> r = list ;
        list = null ;
        return r ;
    }
    
    public List<Token> nextOrNull()
    {
        if ( ! hasNext() )
            return null ;
        List<Token> r = list ;
        list = null ;
        return r ;
    }
    
    @Override
    public void remove()
    { throw new UnsupportedOperationException() ; }

    @Override
    public Iterator<List<Token>> iterator()
    {
        return this ;
    }

    @Override
    public void close()
    {
        if ( atEnd != null )
            atEnd.end() ;
    }
}

/*
 * (c) Copyright 2009 Hewlett-Packard Development Company, LP
 * 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. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
 */