/*
 * @(#)Reply.java	1.2 04/07/26
 * 
 * Copyright (c) 2004 Sun Microsystems, Inc. All Rights Reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 * 
 * -Redistribution of source code must retain the above copyright notice, this
 *  list of conditions and the following disclaimer.
 * 
 * -Redistribution 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.
 * 
 * Neither the name of Sun Microsystems, Inc. or the names of contributors may 
 * be used to endorse or promote products derived from this software without 
 * specific prior written permission.
 * 
 * This software is provided "AS IS," without a warranty of any kind. ALL 
 * EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND WARRANTIES, INCLUDING
 * ANY IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE
 * OR NON-INFRINGEMENT, ARE HEREBY EXCLUDED. SUN MIDROSYSTEMS, INC. ("SUN")
 * AND ITS LICENSORS SHALL NOT BE LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE
 * AS A RESULT OF USING, MODIFYING OR DISTRIBUTING THIS SOFTWARE OR ITS
 * DERIVATIVES. IN NO EVENT WILL SUN OR ITS LICENSORS BE LIABLE FOR ANY LOST 
 * REVENUE, PROFIT OR DATA, OR FOR DIRECT, INDIRECT, SPECIAL, CONSEQUENTIAL, 
 * INCIDENTAL OR PUNITIVE DAMAGES, HOWEVER CAUSED AND REGARDLESS OF THE THEORY 
 * OF LIABILITY, ARISING OUT OF THE USE OF OR INABILITY TO USE THIS SOFTWARE, 
 * EVEN IF SUN HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
 * 
 * You acknowledge that this software is not designed, licensed or intended
 * for use in the design, construction, operation or maintenance of any
 * nuclear facility.
 */

import java.io.*;
import java.nio.*;
import java.nio.charset.*;

/**
 * An object used for sending Content to the requestor.
 *
 * @author Mark Reinhold
 * @author Brad R. Wetmore
 * @version 1.2, 04/07/26
 */
class Reply implements Sendable {

    /**
     * A helper class which define the HTTP response codes
     */
    static class Code {

	private int number;
	private String reason;
	private Code(int i, String r) { number = i; reason = r; }
	public String toString() { return number + " " + reason; }

	static Code OK = new Code(200, "OK");
	static Code BAD_REQUEST = new Code(400, "Bad Request");
	static Code NOT_FOUND = new Code(404, "Not Found");
	static Code METHOD_NOT_ALLOWED = new Code(405, "Method Not Allowed");

    }

    private Code code;
    private Content content;
    private boolean headersOnly;

    Reply(Code rc, Content c) {
	this(rc, c, null);
    }

    Reply(Code rc, Content c, Request.Action head) {
	code = rc;
	content = c;
	headersOnly = (head == Request.Action.HEAD);
    }

    private static String CRLF = "\r\n";
    private static Charset ascii = Charset.forName("US-ASCII");

    private ByteBuffer hbb = null;

    private ByteBuffer headers() {
	CharBuffer cb = CharBuffer.allocate(1024);
	for (;;) {
	    try {
		cb.put("HTTP/1.0 ").put(code.toString()).put(CRLF);
		cb.put("Server: niossl/0.1").put(CRLF);
		cb.put("Content-type: ").put(content.type()).put(CRLF);
		cb.put("Content-length: ")
		    .put(Long.toString(content.length())).put(CRLF);
		cb.put(CRLF);
		break;
	    } catch (BufferOverflowException x) {
		assert(cb.capacity() < (1 << 16));
		cb = CharBuffer.allocate(cb.capacity() * 2);
		continue;
	    }
	}
	cb.flip();
	return ascii.encode(cb);
    }

    public void prepare() throws IOException {
	content.prepare();
	hbb = headers();
    }

    public boolean send(ChannelIO cio) throws IOException {

	if (hbb == null)
	    throw new IllegalStateException();

	if (hbb.hasRemaining()) {
	    if (cio.write(hbb) <= 0)
		return true;
	}

	if (!headersOnly) {
	    if (content.send(cio))
		return true;
	}

	if (!cio.dataFlush())
	    return true;

	return false;
    }

    public void release() throws IOException {
	content.release();
    }
}