/* this belongs to the WebRaveler package */
package webraveler.plugin;

import java.util.*;

import webraveler.http.HTTPResponse;
import webraveler.html.HTMLPage2;
import webraveler.ravel.PluginAPI;
import webraveler.ravel.Raveler;
import webraveler.vurl.HelpVURL;
import webraveler.vurl.PluginChangePref;
import webraveler.vurl.PluginConfig;
import webraveler.vurl.TextReplaceVURL;

/**
 * A Web Raveler plugin to replace text (by matching a regular 
 * expression) in the entity of any HTTPMessage with content-type
 * text/* (that is, any content-type which starts with "text/", not
 * the content-type that equals "text/*")
 *
 * @author The Web Raveler Development Squad
 * @version 1.0
 */
public class TextReplacePlugin extends webraveler.ravel.RavelerPlugin {
  /* variables */
  String fullURL;
  boolean DEBUG = false;
  
  /* constructors */
  
  /**
   * The default constructor, called from WebRaveler2.Raveler 
   */
   public TextReplacePlugin() {
     name = "TextReplacePlugin";
     mimeTypes.add("text/html");
   }
  
  /* methods */

  /**
   * Start executing the plugin when given a response
   *
   * @param response an HTTPResponse with the response to be modified
   * @return an HTTPResponse object, the result of running the plugin on the input response
   */
  public HTTPResponse execute(HTTPResponse response, Hashtable attributes) {
      if (DEBUG) System.out.println("\nTextReplacePlugin: executing...");
      String pattern = (String) attributes.get("pattern");
      if (DEBUG) System.out.println("TextReplacePlugin: pattern: "+pattern); 
      String replacement = (String) attributes.get("replacement");
      if (DEBUG) System.out.println("TextReplacePlugin: replacement: "+replacement); 
      if (DEBUG) System.out.println("TextReplacePlugin: getting page html");
      HTMLPage2 html = response.getHtmlPage();
      html.replaceText("Debian","Red Hat"); 
      if (DEBUG) System.out.println("TextReplacePlugin: page html:");
      if (DEBUG) System.out.println(""+html+"\n");
      if (DEBUG) System.out.println("TextReplacePlugin: replacing text");
      //response.getHtmlPage().replaceText(pattern,replacement);
      if (DEBUG) System.out.println("TextReplacePlugin: done replacing text...correcting content length");
      response.correctContentLength();
      if (DEBUG) System.out.println("TextReplacePlugin: finished\n");
      return response;
  }
  
  
  
  /**
   * Do the setup stuff with Raveler - banner setup, etc.
   * Put the plugin on Raveler's "plugin vector"
   */
  public boolean initialize() {
    /* Add virtual urls for configuration */
    String fullURL1;
    Vector attributes = new Vector();
    attributes.add("pattern");
    attributes.add("replacement");
    PluginChangePref changePref = new webraveler.vurl.PluginChangePref("TextReplacePlugin");
    fullURL1 = PluginAPI.addPermanentVirtualURL(ravel,name,"changePref",changePref);
    PluginConfig config = new PluginConfig("TextReplacePlugin",attributes,fullURL1);
    fullURL = PluginAPI.addConfigVirtualURL(ravel,name,config);

    /* some helpful HTML to display to the user */
    String helpfulHTML = new String();
    helpfulHTML += "<html><head>"+Raveler.ravelerCSS+"<title>WebRaveler2 :: TextReplacePlugin Help Page</title></head>";
    helpfulHTML += "<body><p class='level1'>TextReplacePlugin :: Help</p>";
    helpfulHTML += "<p><h3><ul><li>To use this plugin, enter a regular expression and some replacement text into the Configuration ";
    helpfulHTML += "page.</li><li> Then, activate the plugin through the plugins menu at the top of any Raveled page. </li><li> When the ";
    helpfulHTML += "page is reloaded, or a new page is opened, any text matching the given regular expression will be ";
    helpfulHTML += "replaced by the replacement you entered.</li></ul>  Thank you for using TextReplacePlugin.</h3>";
    helpfulHTML += "</p><p><h4>For more information on allowable regular expressions, please visit Sun's Java API ";
    helpfulHTML += "at <a href='http://java.sun.com/' target='_blank'>http://java.sun.com</a>.</h4></p></body></html>";

    HelpVURL help = new HelpVURL(helpfulHTML);
    fullURL = PluginAPI.addHelpVirtualURL(ravel,name,help);
    TextReplaceVURL textReplace = new TextReplaceVURL();
    fullURL = PluginAPI.addPluginVirtualURL(ravel,name,textReplace);
    return true;
  }
  
  /**
   * Terminate the Plugin - Hasta la vista, BABY!
   */
  public void terminate() {
  }
  



  /**
   * Return the default configuration for this plugin as a hash table. 
   *
   */
  public void setDefaultAttributes() {
     attributes = new Hashtable();
     attributes.put("pattern","[Gg]oogle");
     attributes.put("replacement","Poop");
  }
    
} //class RavelerPlugin