/*

 *   StarOffice 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 com.so.news.storage;

import java.sql.ResultSet;

import java.sql.SQLException;

import java.util.Date;

import java.util.HashMap;

import java.util.Map;

import java.util.Map.Entry;

import java.util.UUID;

import com.so.news.Config;

import com.so.news.Debug;

/**

 * Represents a newsgroup article.

 * @author Christian Lins

 * @author Denis Schwerdel

 */

public class Article

{

  /**

   * Loads the Article identified by the given ID from the Database.

   * @param messageID

   * @return null if Article is not found or if an error occurred.

   */

  public static Article getByMessageID(String messageID)

  {

    try

    {

      return Database.getInstance().getArticle(messageID);

    }

    catch(SQLException ex)

    {

      ex.printStackTrace(Debug.getInstance().getStream());

      return null;

    }

  }

  public static Article getByNumberInGroup(Group group, int number)

    throws SQLException

  {

    long gid = group.getID(); 

    return Database.getInstance().getArticle(gid, number); // Is number her correct?

  }

  private String              body      = "";

  private long                groupID   = -1;

  private Map<String, String> header    = new HashMap<String, String>();

  private int                 numberInGroup = -1;

  private String              msgID     = null;

  /**

   * Default constructor.

   */

  public Article()

  {

  }

  /**

   * Creates a new Article object using the date from the given

   * ResultSet. It is expected that ResultSet.next() was already

   * called by the Database class.

   * This construction has only package visibility.

   * @param rs

   */

  Article(ResultSet rs)

    throws SQLException

  {

    this.body  = rs.getString("body");

    this.msgID = rs.getString("message_id");

    // Parse the header

    parseHeader(rs.getString("header"));

  }

  /**

   * Parses the header fields and puts them into a map for faster access.

   * TODO: There could be fields that go over more than one line, some

   * bad clients do create them.

   * @param hsrc

   */

  private void parseHeader(String hsrc)

  {

    String[] lines = hsrc.split("\n");

    for(String line : lines)

    {

      String[] kv = line.split(":");

      if(kv.length < 2)

      {

        Debug.getInstance().log("Invalid header field: " + line);

        continue;

      }

      else

      {

        // Set value in the header hash map

        String value = kv[1];

        for(int n = 2; n < kv.length; n++)

          value += ":" + kv[n];

        this.header.put(kv[0], value);

      }

    }

  }

  /**

   * Returnes the next Article in the group of this Article.

   * @return

   */

  public Article nextArticleInGroup()

  {

    return null;

  }

  /**

   * Returns the previous Article in the group of this Article.

   * @return

   */

  public Article prevArticleInGroup()

  {

    return null;

  }

  /**

   * Generates a message id for this article and sets it into

   * the header HashMap.

   */

  private String generateMessageID()

  {

    this.msgID = "<" + UUID.randomUUID() + "@"

        + Config.getInstance().get("n3tpd.hostname", "localhost") + ">";

    this.header.put("Message-ID", msgID);

    return msgID;

  }

  /**

   * Tries to delete this article.

   * @return false if the article could not be deleted, otherwise true

   */

  public boolean delete()

  {

    return false;

  }

  /**

   * Checks if all necessary header fields are within this header.

   */

  private void validateHeader()

  {    

    // Forces a MessageID creation if not existing

    getMessageID();

    // Check if the references are correct...

    String rep = header.get("In-Reply-To");

    if(rep == null) // Some clients use only references instead of In-Reply-To

      return; //rep = header.get("References");

    String ref = getMessageID();

    if(rep != null && !rep.equals(""))

    {

      Article art = null; //TODO // getByMessageID(rep, articleDir);

      if(art != null)

      {

        ref = art.header.get("References") + " " + rep;

      }

    }

    header.put("References", ref);

  }

  /**

   * Returns the body string.

   */

  public String getBody()

  {

    return body;

  }

  /**

   * @return Numerical ID of the associated Group.

   */

  long getGroupID()

  {

    if(groupID == -1) // If the GroupID was not determined yet

    {

      // Determining GroupID

      String   newsgroups = this.header.get("Newsgroups");

      if(newsgroups != null)

      {

        String[] newsgroup  = newsgroups.split(",");

        // Crossposting is not supported

        try

        {

          Group group;

          if(newsgroup.length > 0)

            group = Database.getInstance().getGroup(newsgroup[0].trim());

          else

            group = Database.getInstance().getGroup(newsgroups.trim());

          // TODO: What to do if Group does not exist?

          this.groupID = group.getID();

        }

        catch(SQLException ex)

        {

          ex.printStackTrace(Debug.getInstance().getStream());

          System.err.println(ex.getLocalizedMessage());

        }

      }

      else

        System.err.println("Should never happen: Article::getGroupID");

    }

    return this.groupID;

  }

  public void setBody(String body)

  {

    this.body = body;

  }

  public int getNumberInGroup()

  {

    return this.numberInGroup;

  }

  public void setHeader(HashMap<String, String> header)

  {

    this.header = header;

  }

  public void setNumberInGroup(int id)

  {

    this.numberInGroup = id;

  }

  public String getMessageID()

  {

    if(msgID == null)

      msgID = generateMessageID();

    return msgID;

  }

  /**

   * @return Header source code of this Article.

   */

  public String getHeaderSource()

  {

    StringBuffer buf = new StringBuffer();

    for(Entry<String, String> entry : this.header.entrySet())

    {

      buf.append(entry.getKey());

      buf.append(":");

      buf.append(entry.getValue());

      buf.append("\n");

    }

    return buf.toString();

  }

  public Map<String, String> getHeader()

  {

    return this.header;

  }

  public Date getDate()

  {

    try

    {

      String date = this.header.get("Date");

      return new Date(Date.parse(date));

    }

    catch(Exception e)

    {

      e.printStackTrace(Debug.getInstance().getStream());

      return null;

    }

  }

  public void setDate(Date date)

  {

    this.header.put("Date", date.toString());

  }

  @Override

  public String toString()

  {

    return getMessageID();

  }

}