/*

 *   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());

    }

  }

}