/*

 *   SONEWS News Server

 *   see AUTHORS for the list of contributors

 *

 *   This program is free software: you can redistribute it and/or modify

 *   it under the terms of the GNU General Public License as published by

 *   the Free Software Foundation, either version 3 of the License, or

 *   (at your option) any later version.

 *

 *   This program is distributed in the hope that it will be useful,

 *   but WITHOUT ANY WARRANTY; without even the implied warranty of

 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 *   GNU General Public License for more details.

 *

 *   You should have received a copy of the GNU General Public License

 *   along with this program.  If not, see <http://www.gnu.org/licenses/>.

 */

package org.sonews.storage;

import java.io.ByteArrayInputStream;

import java.util.Enumeration;

import javax.mail.Header;

import javax.mail.MessagingException;

import javax.mail.internet.InternetHeaders;

import javax.mail.internet.MimeUtility;

import org.sonews.config.Config;

/**

 * An article with no body only headers.

 * @author Christian Lins

 * @since sonews/0.5.0

 */

public class ArticleHead

{

	protected InternetHeaders headers = null;

	protected String headerSrc = null;

	protected ArticleHead()

	{

	}

	public ArticleHead(String headers)

	{

		try {

			// Parse the header

			this.headers = new InternetHeaders(

				new ByteArrayInputStream(headers.getBytes()));

		} catch (MessagingException ex) {

			ex.printStackTrace();

		}

	}

	/**

	 * Returns the header field with given name.

	 * @param name Name of the header field(s).

	 * @param returnNull If set to true, this method will return null instead

	 *                   of an empty array if there is no header field found.

	 * @return Header values or empty string.

	 */

	public String[] getHeader(String name, boolean returnNull)

	{

		String[] ret = this.headers.getHeader(name);

		if (ret == null && !returnNull) {

			ret = new String[] {""};

		}

		return ret;

	}

	public String[] getHeader(String name)

	{

		return getHeader(name, false);

	}

	/**

	 * Sets the header value identified through the header name.

	 * @param name

	 * @param value

	 */

	public void setHeader(String name, String value)

	{

		this.headers.setHeader(name, value);

		this.headerSrc = null;

	}

	public Enumeration getAllHeaders()

	{

		return this.headers.getAllHeaders();

	}

	/**

	 * @return Header source code of this Article.

	 */

	public String getHeaderSource()

	{

		if (this.headerSrc != null) {

			return this.headerSrc;

		}

		StringBuffer buf = new StringBuffer();

		for (Enumeration en = this.headers.getAllHeaders(); en.hasMoreElements();) {

			Header entry = (Header) en.nextElement();

			String value = entry.getValue().replaceAll("[\r\n]", " ");

			buf.append(entry.getName());

			buf.append(": ");

			buf.append(MimeUtility.fold(entry.getName().length() + 2, value));

			if (en.hasMoreElements()) {

				buf.append("\r\n");

			}

		}

		this.headerSrc = buf.toString();

		return this.headerSrc;

	}

	/**

	 * Sets the headers of this Article. If headers contain no

	 * Message-Id a new one is created.

	 * @param headers

	 */

	public void setHeaders(InternetHeaders headers)

	{

		this.headers = headers;

		this.headerSrc = null;

		validateHeaders();

	}

	/**

	 * Checks some headers for their validity and generates an

	 * appropriate Path-header for this host if not yet existing.

	 * This method is called by some Article constructors and the

	 * method setHeaders().

	 * @return true if something on the headers was changed.

	 */

	protected void validateHeaders()

	{

		// Check for valid Path-header

		final String path = getHeader(Headers.PATH)[0];

		final String host = Config.inst().get(Config.HOSTNAME, "localhost");

		if (!path.startsWith(host)) {

			StringBuffer pathBuf = new StringBuffer();

			pathBuf.append(host);

			pathBuf.append('!');

			pathBuf.append(path);

			this.headers.setHeader(Headers.PATH, pathBuf.toString());

		}

	}

}