/*
 * Source: Adam Perer Major revision made by Yejun Wu in April, 2005
 *
 * This version tries to remove duplicates in a thread
 */

package edu.umd.email;

import java.awt.AWTEvent;
import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.Toolkit;
import java.awt.datatransfer.Clipboard;
import java.awt.datatransfer.StringSelection;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
//import java.util.ArrayList;
//import java.util.TreeSet;
//import java.util.Comparator;
import java.util.*;

import javax.swing.BorderFactory;
import javax.swing.Box;
import javax.swing.BoxLayout;
import javax.swing.JButton;
import javax.swing.JCheckBox;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JMenuItem;
import javax.swing.JPanel;
import javax.swing.JPopupMenu;
import javax.swing.JRadioButton;
import javax.swing.JScrollPane;
import javax.swing.JSplitPane;
import javax.swing.JTextArea;
import javax.swing.JTextField;
import javax.swing.JTree;
import javax.swing.border.Border;
import javax.swing.border.EtchedBorder;
import javax.swing.border.TitledBorder;
import javax.swing.event.TreeSelectionEvent;
import javax.swing.event.TreeSelectionListener;
import javax.swing.tree.DefaultMutableTreeNode;
import javax.swing.tree.DefaultTreeModel;
import javax.swing.tree.TreeSelectionModel;

import org.apache.lucene.analysis.Analyzer;
import org.apache.lucene.document.DateField;
import org.apache.lucene.document.Document;
import org.apache.lucene.index.Term;
import org.apache.lucene.queryParser.QueryParser;
import org.apache.lucene.search.BooleanQuery;
import org.apache.lucene.search.Hits;
import org.apache.lucene.search.IndexSearcher;
import org.apache.lucene.search.Query;
import org.apache.lucene.search.TermQuery;

import edu.umd.email.enron.EmailAnalyzer;

public class SearchDeDup extends JFrame {

	private static final int MAXHITS = 100;

	private int defaultNumHits = MAXHITS;

	//getContentPane() has 2 panes with BorderLayout
	// topPane (consisting of: listPane, fromPaneParent, toPaneParent,
	// subjectPane, textPane);
	// bottomSplitPane(consisting of treePane and bodyTextPane).
	private JComboBox collectionBox;

	private JTextField hitsInput;

	private JTextField fromAddressInput, toAddressInput, fromNameInput,
			toNameInput, subjectInput;

	private JTextArea bodyInput, output, bodyTextArea;

	private JButton search, reset, search2;

	private JRadioButton enronButton, w3cButton;

	private JScrollPane treePane, bodyTextPane;

	private JScrollPane outputPane, inputPane, fromAddressInputPane;

	private JScrollPane toAddressInputPane, subjectInputPane,
			fromNameInputPane;

	private JScrollPane toNameInputPane, listScrollPane;

	private JPanel fromPaneParent, toPaneParent;

	private JPanel topPane, fromPane, textPane, toPane, subjectPane, listPane,
			fromToPane;

	private JSplitPane bottomSplitPane; //load treePane and bodyTextPane

	private JCheckBox threadCheckBox;

	private DefaultTreeModel model;

	private JTree tree;

	private DefaultMutableTreeNode root, group;

	private IndexSearcher searcher;

	private Analyzer analyzer, threadAnalyzer;

	private String answerText = "";

	private static int lastHit = -1;

	private static int lastHit2 = -1;

	private static String lastSearch = "";

	private static String lastSearch2 = "";

	private Hits hits = null;

	private Hits hits2 = null;

	private int start, end, top;

	private String[] collectionWords = { "Enron", "W3C" };

	private String mySelection = "";

	//private Vector seen = new Vector();
	JPopupMenu popup;

	public static void main(String args[]) {
		SearchDeDup search = new SearchDeDup();
		//search.createPopupMenu();
		search.show();
		//new Search().show();
	}

	private void exitForm(java.awt.event.WindowEvent evt) {
		System.exit(0);
	}

	public SearchDeDup() {

		getContentPane().setLayout(new BorderLayout(3, 3));//horizontal and
														   // vertical gaps
														   // between components

		setTitle("Email Archive Explorer");
		addWindowListener(new java.awt.event.WindowAdapter() {
			public void windowClosing(java.awt.event.WindowEvent evt) {
				exitForm(evt);
			}
		});

		topPane = new JPanel();
		//topPane.setLayout(new GridLayout(5, 1));//rows, cols
		//There is no space between components in a BoxLayout
		topPane.setLayout(new BoxLayout(topPane, BoxLayout.Y_AXIS));

		listPane = new JPanel();
		listPane.setLayout(new FlowLayout(FlowLayout.LEFT));

		//fromPaneParent: to hold fromPane with a titled border
		fromPaneParent = new JPanel();
		fromPaneParent.setLayout(new FlowLayout(FlowLayout.LEFT));

		//toPaneParent: to hold toPane with a titled border
		toPaneParent = new JPanel();
		toPaneParent.setLayout(new FlowLayout(FlowLayout.LEFT));

		fromPane = new JPanel();
		fromPane.setLayout(new FlowLayout(FlowLayout.LEFT));//FlowLayout.LEFT
		//fromPane.setLayout(new BoxLayout(fromPane, BoxLayout.X_AXIS));
		//fromPane.setAlignmentX(JPanel.LEFT_ALIGNMENT);

		toPane = new JPanel();
		toPane.setLayout(new FlowLayout(FlowLayout.LEFT));
		//toPane.setAlignmentX(JPanel.LEFT_ALIGNMENT);

		fromToPane = new JPanel();
		fromToPane.setLayout(new FlowLayout(FlowLayout.LEFT));

		textPane = new JPanel();
		textPane.setLayout(new FlowLayout(FlowLayout.LEFT));

		subjectPane = new JPanel();
		subjectPane.setLayout(new FlowLayout(FlowLayout.LEFT));

		listPane.add(new JLabel("Select Collection: "));
		collectionBox = new JComboBox(collectionWords);
		MyComboListener comboListener = new MyComboListener(collectionBox);
		collectionBox.addActionListener(comboListener);
		listPane.add(collectionBox);

		listPane.add(Box.createRigidArea(new Dimension(20, 0))); //filler
		listPane.add(new JLabel("Show max number of hits: "));
		hitsInput = new JTextField("100", 4); //default hits: 100, width = 5
		listPane.add(hitsInput);

		listPane.add(Box.createRigidArea(new Dimension(20, 0))); //filler
		threadCheckBox = new JCheckBox("Retrieve threads");
		listPane.add(threadCheckBox);
		listPane.add(new JLabel("(can be time-costly)"));

		Dimension size = new Dimension(420, 62);//width, height for fromPane
												// and toPane
		Dimension maxsize = new Dimension(420, 65);
		fromPane.setMaximumSize(maxsize);
		fromPane.setPreferredSize(size);
		fromPane.setMinimumSize(size);

		toPane.setMaximumSize(size);
		toPane.setPreferredSize(size);
		toPane.setMinimumSize(size);

		fromPane.add(new JLabel("Address:"));
		fromAddressInput = new JTextField(14);

		fromPane.add(fromAddressInput);

		//use invisible components as filler
		fromPane.add(Box.createRigidArea(new Dimension(2, 0)));

		fromPane.add(new JLabel("Name:"));
		fromNameInput = new JTextField(10);

		fromPane.add(fromNameInput);

		//see: http://java.sun.com/docs/books/tutorial/uiswing/misc/border.html
		Border loweredetched, blackline;
		loweredetched = BorderFactory.createEtchedBorder(EtchedBorder.LOWERED);
		TitledBorder fromTitledBorder = BorderFactory.createTitledBorder(
				loweredetched, "From");
		fromPane.setBorder(BorderFactory.createTitledBorder(fromTitledBorder));

		fromPaneParent.add(fromPane);
		fromToPane.add(fromPaneParent);

		toPane.add(new JLabel("Address:"));
		toAddressInput = new JTextField(14);

		toPane.add(toAddressInput);

		//use invisible components as filler
		toPane.add(Box.createRigidArea(new Dimension(2, 0)));

		toPane.add(new JLabel("Name:"));
		toNameInput = new JTextField(10);

		toPane.add(toNameInput);

		TitledBorder toTitledBorder = BorderFactory.createTitledBorder(
				loweredetched, "To");
		toPane.setBorder(BorderFactory.createTitledBorder(toTitledBorder));

		toPaneParent.add(toPane);
		fromToPane.add(toPaneParent);

		subjectPane.add(new JLabel("Subject:"));
		//use invisible components as filler
		subjectPane.add(Box.createRigidArea(new Dimension(10, 0)));
		subjectInput = new JTextField(20);

		subjectPane.add(subjectInput);
		subjectPane
				.add(new JLabel("(Note: A subject query is case sensitive)"));

		textPane.add(new JLabel("Body Text: "));
		bodyInput = new JTextArea(2, 50); //2 rows, 50 cols
		bodyInput.setLineWrap(true);
		bodyInput.setWrapStyleWord(true);
		bodyInput.setEditable(true);
		inputPane = new JScrollPane();
		inputPane.setViewportView(bodyInput);
		textPane.add(inputPane);

		search = new JButton();
		search.setText("Search");
		search.addActionListener(new java.awt.event.ActionListener() {
			public void actionPerformed(java.awt.event.ActionEvent evt) {
				searchActionPerformed(evt);
			}
		});
		textPane.add(search);

		reset = new JButton();
		reset.setText("Reset");
		reset.addActionListener(new java.awt.event.ActionListener() {
			public void actionPerformed(java.awt.event.ActionEvent evt) {
				resetActionPerformed(evt);
			}
		});
		textPane.add(reset);

		topPane.add(listPane);
		topPane.add(fromToPane);
		topPane.add(subjectPane);
		topPane.add(textPane);
		getContentPane().add(topPane, BorderLayout.NORTH);

		//construct tree
		root = new DefaultMutableTreeNode("Emails");
		//root.setUserObject("test"); //changes root label
		group = new DefaultMutableTreeNode("Group");
		//root.insert(group, 0);
		model = new DefaultTreeModel(root);
		tree = new JTree(model);

		//add scroll pane with tree to content pane
		treePane = new JScrollPane(tree);
		//getContentPane().add(treePane, BorderLayout.CENTER);

		bodyTextArea = new JTextArea(8, 80);
		bodyTextArea.setLineWrap(true);
		bodyTextArea.setWrapStyleWord(true);
		bodyTextArea.setEditable(false);
		bodyTextPane = new JScrollPane();
		bodyTextPane.setViewportView(bodyTextArea);
		//textPane.add(bodyTextPane);
		//getContentPane().add(bodyTextPane, BorderLayout.SOUTH);

		JMenuItem menuItem;

		//Create the popup menu.
		popup = new JPopupMenu();
		enableEvents(AWTEvent.MOUSE_EVENT_MASK);
		menuItem = new JMenuItem("Copy Message");
		menuItem.addActionListener(new ActionListener() {
			public void actionPerformed(ActionEvent e) {
				String cmd = e.getActionCommand();
				//The getActionCommand method of ActionEvent returns the label
				// of the MenuItem.
				System.out.println(e.getActionCommand());
				System.out.println("plan to copy");
				//JMenuItem source = (JMenuItem)(e.getSource());
				Clipboard cb = Toolkit.getDefaultToolkit().getSystemClipboard();
				String s = bodyTextArea.getText();
				StringSelection contents = new StringSelection(s);
				cb.setContents(contents, null);
			}
		});

		popup.add(menuItem);

		//Add a listener to bodyTextArea to display pop-up
		bodyTextArea.addMouseListener(new MouseAdapter() {
			public void mousePressed(MouseEvent evt) {
				if (evt.isPopupTrigger()) {
					popup.show(evt.getComponent(), evt.getX(), evt.getY());
				}
			}

			public void mouseReleased(MouseEvent evt) {
				if (evt.isPopupTrigger()) {
					popup.show(evt.getComponent(), evt.getX(), evt.getY());
				}
			}
		});

		bottomSplitPane = new JSplitPane(JSplitPane.VERTICAL_SPLIT, treePane,
				bodyTextPane);
		//bottomSplitPane.setOneTouchExpandable(true);//completely expand
		bottomSplitPane.setDividerLocation(300);
		getContentPane().add(bottomSplitPane, BorderLayout.CENTER);
		pack();

		int mode = TreeSelectionModel.SINGLE_TREE_SELECTION;
		tree.getSelectionModel().setSelectionMode(mode);

		//Listen for when the selection changes.
		tree.addTreeSelectionListener(new TreeSelectionListener() {
			public void valueChanged(TreeSelectionEvent e) {
				DefaultMutableTreeNode node = (DefaultMutableTreeNode) tree
						.getLastSelectedPathComponent();
				if (node == null)
					return;

				Object nodeInfo = node.getUserObject();
				//if (node.isLeaf()) {
				//System.out.println("inside addTreeSelectionListener");
				String metadata = (String) nodeInfo;
				//if (metadata.startsWith("FOLDER: ")){
				//xxx;
				
				int folderStart = metadata.indexOf("FOLDER: ");
				String fileName = metadata.substring(folderStart + 8, metadata
						.length() - 1);
				//String fileName = metadata.substring(8);
				String wholeDocument = "";
				if (fileName.indexOf(";") == -1) {//semicolon does not occur			
				    System.out.println("reading =" + fileName + "=");				
				    try {
					    File theFile = new File(fileName);
					    FileReader fileReader = new FileReader(theFile);
					    BufferedReader reader = new BufferedReader(fileReader);
					    String line = null;
					    while ((line = reader.readLine()) != null) {
						    wholeDocument += line + "\n";
					    }
					    reader.close();
				    } catch (Exception ex) {
					    ex.printStackTrace();
				    }
				} else {
				    StringTokenizer folderParser = new StringTokenizer(fileName, ";");
				    while (folderParser.hasMoreTokens()){
				    	String aFileName = folderParser.nextToken();
				    	try {
				    		File aFile = new File(aFileName);
				    		FileReader fReader = new FileReader(aFile);
				    		BufferedReader aReader = new BufferedReader(fReader);
				    		String aLine = null;
				    		while ((aLine = aReader.readLine()) != null){
				    			wholeDocument += aLine + "\n";
				    		}
				    		aReader.close();
				    		wholeDocument += 
				    			"----------------------------------------------------------\n";
				    	}catch (Exception ex) {
						    ex.printStackTrace();
					    }//end try
				    }//end while
				}//end else
				
				bodyTextArea.setText(wholeDocument);
				//} else
				//  bodyTextArea.setText(metadata);
				//}
			}//end public void...
		});
		//SelectColl4Search();//this does not work. actionPerformed effect
		// delayed
	}//end Search()

	/**
	 * Don't use a MouseListener, since in Win95/NT you have to check
	 * isPopupTrigger in mouseReleased, but do it in mousePressed in Solaris
	 * (boo!).
	 * 
	 * This method is required to make the popup menu, if any, pop up. It uses
	 * the low-level Java 1.1 event handling mechanism to test all mouse events
	 * (except mouse motion events) to see if they are the platform- dependent
	 * popup menu trigger. If so, it calls show() to pop the popup up. If not,
	 * it passes the event to the superclass version of this method so that it
	 * is dispatched as usual and can be passed to the listener object
	 * registered by the init method for scribbling.
	 */
	public void processMouseEvent(MouseEvent event) {
		if (popup != null && event.isPopupTrigger()) {
			popup.show(event.getComponent(), event.getX(), event.getY());
			System.out.println("show popup menu");
		}
		super.processMouseEvent(event);
	}

	//select a collection to search
	public void SelectColl4Search() {
		try {
			if (mySelection.equals("Enron")) {
				searcher = new IndexSearcher("indexes/enron");
				//searcher = new IndexSearcher("C:/Eclipse/umdex_v1.00/indexes/enron");
				
				System.out.println("searching in enron");
			} else if (mySelection.equals("W3C")) {
				searcher = new IndexSearcher("indexes/w3c");
				System.out.println("searching in w3c");
			}
			analyzer = new EmailAnalyzer(); //initialize analyzer
			threadAnalyzer = new EmailAnalyzer(); //initialize analyzer
			System.out.println("Index opened with " + searcher.maxDoc()
					+ " documents.");
		} catch (Exception e) {
			System.out.println("when getting a searcher, caught a "
					+ e.getClass() + "\n with message: " + e.getMessage());
		}
	}//end Search()

	class MyComboListener implements ActionListener {
		JComboBox combo;

		Object currentItem;

		MyComboListener(JComboBox combo) {
			this.combo = combo;
			//combo.setSelectedIndex(0); //preselect "Enron"
			currentItem = combo.getSelectedItem();
			mySelection = (String) currentItem;

		}

		public void actionPerformed(ActionEvent e) {
			Object tempItem = combo.getSelectedItem();
			currentItem = tempItem;
			combo.setSelectedItem(currentItem);
			mySelection = (String) currentItem;
			//System.out.println("actionperformed! currentItem is "+
			// (String)currentItem);
		}

		public Object getCurrentItem() {
			//System.out.println("returning currentItem: " +
			// (String)currentItem);
			return currentItem;
		}
	}

	//reset everything to its original state
	private void resetActionPerformed(java.awt.event.ActionEvent evt) {
		bodyInput.setText("");
		fromAddressInput.setText("");
		toAddressInput.setText("");
		subjectInput.setText("");
		fromNameInput.setText("");
		toNameInput.setText("");
		bodyTextArea.setText("");
		//enronButton.setSelected(true);
		//w3cButton.setSelected(false);
		collectionBox.setSelectedIndex(0);
		hitsInput.setText("100");
		threadCheckBox.setSelected(false);

		hits = null;
		root.setUserObject("Emails");
		addHitsToTree(hits);
		treePane.remove(tree);
		tree.updateUI();
	}

	//actions performed when the "Search" button is clicked
	private void searchActionPerformed(java.awt.event.ActionEvent evt) {
		System.out.println("SearchActionPerformed!");
		SelectColl4Search();

		if (!hitsInput.getText().equals("")) {
			defaultNumHits = Integer.parseInt(hitsInput.getText());
		}
		//System.out.println("max num of hits to show = " + defaultNumHits);

		//Note: if nothing is input into a query box, input.getText() is an
		// empty string,
		//i.e., a "" string rather than a null.
		//query.toString() usually brings its field name with it, such as
		// "contents:"
		//If inputText()=="", QueryParse throws an exception

		bodyTextArea.setText("");//whenever "Search" is clicked, remove
								 // anything in "bodyTextArea"
		boolean fromAddressQueryEmpty = true, fromNameQueryEmpty = true;
		boolean toAddressQueryEmpty = true, toNameQueryEmpty = true;
		boolean subjectQueryEmpty = true, bodyQueryEmpty = true;

		try {
			BooleanQuery boolQuery = new BooleanQuery();
			Query fromAddressQuery = null, bodyQuery = null, finalQuery = null;
			Query fromNameQuery = null, toAddressQuery = null, toNameQuery = null;
			Query subjectQuery = null;

			if (!fromAddressInput.getText().equals("")) {
				fromAddressQueryEmpty = false;
				fromAddressQuery = new TermQuery(new Term("fromAddress",
						fromAddressInput.getText()));
			}

			if (!fromNameInput.getText().equals("")) {
				fromNameQueryEmpty = false;
				fromNameQuery = QueryParser.parse(fromNameInput.getText(),
						"fromName", analyzer);
			}

			if (!toAddressInput.getText().equals("")) {
				toAddressQueryEmpty = false;
				toAddressQuery = new TermQuery(new Term("toAddress",
						toAddressInput.getText()));
			}

			if (!toNameInput.getText().equals("")) {
				toNameQueryEmpty = false;
				toNameQuery = QueryParser.parse(toNameInput.getText(),
						"toName", analyzer);
			}
			//System.out.println("subjectInput.getText()= " + "=" +
			// subjectInput.getText()+"=");

			if (!subjectInput.getText().equals("")) {
				subjectQueryEmpty = false;
				subjectQuery = QueryParser.parse(subjectInput.getText(),
						"subject", analyzer);
			}
			//System.out.println("bodyInput.getText() = " + "=" +
			// bodyInput.getText() + "=");

			if (!bodyInput.getText().equals("")) {
				bodyQueryEmpty = false;
				bodyQuery = QueryParser.parse(bodyInput.getText(), "contents",
						analyzer);
			}

			if (fromAddressQueryEmpty && fromNameQueryEmpty
					&& toAddressQueryEmpty && toNameQueryEmpty
					&& subjectQueryEmpty && bodyQueryEmpty) {
				bodyTextArea.setText("Warning: empty queries!");
			} else if (!fromAddressQueryEmpty && fromNameQueryEmpty
					&& toAddressQueryEmpty && toNameQueryEmpty
					&& subjectQueryEmpty && bodyQueryEmpty) {
				hits = searcher.search(fromAddressQuery);
				//System.out.println("executing fromAddressQuery: "+
				// fromAddressQuery.toString());
				//System.out.println("hits="+hits.length());
			} else if (fromAddressQueryEmpty && !fromNameQueryEmpty
					&& toAddressQueryEmpty && toNameQueryEmpty
					&& subjectQueryEmpty && bodyQueryEmpty) {
				hits = searcher.search(fromNameQuery);
				//System.out.println("executing fromNameQuery:
				// "+fromNameQuery.toString());
				//System.out.println("hits="+hits.length());
			} else if (fromAddressQueryEmpty && fromNameQueryEmpty
					&& !toAddressQueryEmpty && toNameQueryEmpty
					&& subjectQueryEmpty && bodyQueryEmpty) {
				hits = searcher.search(toAddressQuery);
				//System.out.println("executing toAddressQuery:
				// "+toAddressQuery.toString());
				//System.out.println("hits="+hits.length());
			} else if (fromAddressQueryEmpty && fromNameQueryEmpty
					&& toAddressQueryEmpty && !toNameQueryEmpty
					&& subjectQueryEmpty && bodyQueryEmpty) {
				hits = searcher.search(toNameQuery);
				//System.out.println("executing toNameQuery:
				// "+toNameQuery.toString());
				//System.out.println("hits="+hits.length());
			} else if (fromAddressQueryEmpty && fromNameQueryEmpty
					&& toAddressQueryEmpty && toNameQueryEmpty
					&& !subjectQueryEmpty && bodyQueryEmpty) {
				hits = searcher.search(subjectQuery);
				//System.out.println("executing subjectQuery:
				// "+subjectQuery.toString());
				//System.out.println("hits="+hits.length());
			} else if (fromAddressQueryEmpty && fromNameQueryEmpty
					&& toAddressQueryEmpty && toNameQueryEmpty
					&& subjectQueryEmpty && !bodyQueryEmpty) {
				hits = searcher.search(bodyQuery);
				//System.out.println("executing bodyQuery: " +
				// bodyQuery.toString());
				//System.out.println("hits="+hits.length());
			} else {//compose a boolean query
				if (!fromAddressQueryEmpty)
					boolQuery.add(fromAddressQuery, true, false);
				if (!fromNameQueryEmpty)
					boolQuery.add(fromNameQuery, true, false);
				if (!toAddressQueryEmpty)
					boolQuery.add(toAddressQuery, true, false);
				if (!toNameQueryEmpty)
					boolQuery.add(toNameQuery, true, false);
				if (!subjectQueryEmpty)
					boolQuery.add(subjectQuery, true, false);
				if (!bodyQueryEmpty)
					boolQuery.add(bodyQuery, true, false);
				hits = searcher.search(boolQuery);
				//System.out.println("executing boolQuery: " +
				// boolQuery.toString());
				//System.out.println("hits=" + hits.length());
			}

			//change root label from "Emails" to number of "Emails Retrieved":

			root.setUserObject(hits.length() + " Emails Retrieved");

			if (threadCheckBox.isSelected())
				addHitsToTree(hits);
			else
				addHitsSimply(hits);

		} catch (Exception e) {
			System.out.println(" inside SearchActionPerformed: caught a "
					+ e.getClass() + "\n with message: " + e.getMessage());

			e.printStackTrace();
		}
	}

	//present the hits in a JTree, but not in threads
	void addHitsSimply(Hits hits) {
		//clean the tree
		Hits h = null;
		addHitsToTree(h);
		treePane.remove(tree);
		tree.updateUI();

		try {
			for (int i = 0; (i < hits.length()) && (i < defaultNumHits); i++) {
				org.apache.lucene.document.Document doc = hits.doc(i);
				//doc.get("date") is a strange String like 0bwma9ncg.
				//Lucene's DateField
				String date = DateField.stringToDate(doc.get("date")).toString();
				//System.out.println("doc.getdate: " + doc.get("date"));

				String subject = doc.get("subject");

				// Hack to remove any quotes that appear in the subject line
				subject = subject.replaceAll("\\\"", "");

				subject = "\"" + subject + "\""; //plan to make a phrase query
				//System.out.println("Node: " + line + " subject: " + subject);

				// Hack to protect against a zero-length subject line
				if (subject.length() <= 2) {
					subject = "\"<<Empty Subject Line>>\"";
				}

				DefaultMutableTreeNode emailNode = new DefaultMutableTreeNode(
						(i + 1) + "--" + subject + "    [FROM: " + "\n"
								+ doc.get("fromAddress") + " ("
								+ doc.get("fromName") + ")] ----" + date
								+ " ----[FOLDER: " + doc.get("folder") + "]");
				root.add(emailNode);
			}//end for
			tree.updateUI();
		} catch (Exception e) {
			System.out.println("inside AddHitsSimply: caught a " + e.getClass()
					+ "\n with message: " + e.getMessage());
			//return "ERROR!\n";
			e.printStackTrace();
		}
	}

	//present the hits in a JTree and in threads
	void addHitsToTree(Hits hits) {
		try {
			String answer = "";
            TreeSet threadDocDeDupSet;
            
			root.removeAllChildren();
			//if (hits.length()==0)
			//bodyTextArea.setText("");

			int line = 0;
			for (int i = 0; (i < hits.length()) && (i < defaultNumHits); i++) {
				DefaultMutableTreeNode emailNode, textNode;
				org.apache.lucene.document.Document doc = hits.doc(i);

				//doc.get("date") is a strange String like 0bwma9ncg.
				String date = DateField.stringToDate(doc.get("date"))
						.toString();

				//added 6/6/05 for identifying the leading email for a thread
				//String fromAddr = doc.get("fromAddress");
				
				String subject = doc.get("subject");

				// Hack to remove any quotes that appear in the subject line
				subject = subject.replaceAll("\\\"", "");

				subject = "\"" + subject + "\""; //plan to make a phrase query

				// Hack to protect against a zero-length subject line
				if (subject.length() <= 2) {
					subject = "\"<<Empty Subject Line>>\"";
				}

				Query subjectQuery = QueryParser.parse(subject, "subject",
						threadAnalyzer);
				Hits threadHits = searcher.search(subjectQuery);

				//for this doc, get a thread that does not include any duplicates
			
				threadDocDeDupSet = deDuplicate(doc, threadHits); 
				
				//"threadHits.length() == 0" happens when no threads found, in the case
				//of empty subject line. 
				if (threadHits.length() == 0 || threadDocDeDupSet.size() == 1) {
											  
					//DefaultMutableTreeNode(Object userObject):
					//Creates a tree node with no parent, no children, but
					// which allows children,
					//and initializes it with the specified user object.

					emailNode = new DefaultMutableTreeNode((i + 1) + "--" + "("
							+ 1 + ") " + subject + "    [FROM: " + "\n"
							+ doc.get("fromAddress") + " ("
							+ doc.get("fromName") + ")] ----" + date
							+ " ----[FOLDER: " + doc.get("folder") + "]");

					//syntax: insert(MutableTreeNode newChild, int childIndex).
					//Removes newChild from its present parent (if it has a
					// parent), sets the
					//child's parent to this node, and then adds the child to
					// this node's child
					//array at index childIndex.

				} else {
					emailNode = new DefaultMutableTreeNode((i + 1) + "--" + "("
							+ threadDocDeDupSet.size() + ") " + subject
							+ "    [FROM: " + doc.get("fromAddress") + " ("
							+ doc.get("fromName") + ")] ----" + date
							+ " ----[FOLDER: " + doc.get("folder") + "]");
				    /***
					emailNode = new DefaultMutableTreeNode((i + 1) + "--" + "("
							+ threadHits.length() + ") " + subject
							+ "    [FROM: " + doc.get("fromAddress") + " ("
							+ doc.get("fromName") + ")] ----" + date
							+ " ----[FOLDER: " + doc.get("folder") + "]");
					***/
				}//end else

				//if threadDocDeDupSet.size() > 1, do the following:
				if (threadDocDeDupSet.size() > 1){
					int threadCount = 0;
					String threadFolderStr = "";
				    //iterate through the TreeSet					
					Iterator iter = threadDocDeDupSet.iterator();
					while (iter.hasNext()){
						Document threadDoc = (Document)iter.next();	
						String threadDate = DateField.stringToDate(
								threadDoc.get("date")).toString();
						threadFolderStr += threadDoc.get("folder") + ";" ;
					    if (compare2Documents(threadDoc, doc) == false){
						    int k = ++threadCount;
						    DefaultMutableTreeNode threadNode = new DefaultMutableTreeNode(
									k + ". " + threadDoc.get("subject")
											+ "    [FROM: "
											+ threadDoc.get("fromAddress") + " ("
											+ threadDoc.get("fromName") + ")] ----"
											+ threadDate + " ----[FOLDER: "
											+ threadDoc.get("folder") + "]");
							emailNode.add(threadNode);
					    } else ++threadCount;
					}//end while
					
					//add one more node for "printing thread"
					threadFolderStr = "Print Thread [FOLDER: " + threadFolderStr;
					//remove the final semicolon
					int indexOfLastSemiColon = threadFolderStr.lastIndexOf(";");
					threadFolderStr = threadFolderStr.substring(0, indexOfLastSemiColon) + "]" ;
					DefaultMutableTreeNode printThreadNode = new DefaultMutableTreeNode(
							threadFolderStr);
					emailNode.add(printThreadNode);
					
				}//end if (threadDocDeDupSet.size() > 1
				
				/******
				//
				//if threadHits.length()>0, do the following:
				//
				int threadCount = 0;
				int indexOfEmailInThread = 0;
				//locate the email (in the threads) that has already been presented on
				// the top of thread
				for (int m = 0; m < threadHits.length(); m++) {
					org.apache.lucene.document.Document threadDoc = threadHits
							.doc(m);
					String threadDate = DateField.stringToDate(
							threadDoc.get("date")).toString();
					if (date.equals(threadDate)) { //locate an email with the same date												
						indexOfEmailInThread = m;
						break;
					}//end if
				}//end for

				for (int j = 0; j < threadHits.length(); j++) {
					org.apache.lucene.document.Document threadDoc = threadHits.doc(j);
					String threadDate = DateField.stringToDate(
							threadDoc.get("date")).toString();
					if (j != indexOfEmailInThread) {
						int k = j + 1;
						DefaultMutableTreeNode threadNode = new DefaultMutableTreeNode(
								k + ". " + threadDoc.get("subject")
										+ "    [FROM: "
										+ threadDoc.get("fromAddress") + " ("
										+ threadDoc.get("fromName") + ")] ----"
										+ threadDate + " ----[FOLDER: "
										+ threadDoc.get("folder") + "]");
						emailNode.add(threadNode);
					}//end else
				}//end for (int j=0; j<threadHits.length(); j++)
                *****/
				
				root.add(emailNode);

			}//end for (int i = 0; (i<hits.length())&&(i<MAXHITS); i++)

			//Notification from the UIManager that the L&F has changed.
			//Replaces the current UI object with the latest version from the
			// UIManager.
			tree.updateUI();

		} catch (Exception e) {
			System.out
					.println("inside AddHitsToTree: a null tree is added; caught a "
							+ e.getClass()
							+ "\n with message: "
							+ e.getMessage());
		}
	}

	//for a Lucene document "doc", process the Hits retrieved by the subject line of "doc",
	//return a TreeSet of documents sorted by Date, without any duplicates
	//
	//Duplicates can be any of the following:
	//(1)same email sent by same person at different date
	//(2)same emails classified into different folders by same person
	//(3)an email sent to multiple persons (so every receiver gets a same copy)
	//
	//So here I think, if two emails having same fromAddress, toAddress, ccAddress,
	//subject, and contents, then they are very likely to be the same.
	//
	TreeSet deDuplicate(org.apache.lucene.document.Document doc, Hits threadHits){
		TreeSet docSet = new TreeSet( new Comparator(){
		    public int compare(Object o1, Object o2){
		    	org.apache.lucene.document.Document d1 = (org.apache.lucene.document.Document)o1;
		    	org.apache.lucene.document.Document d2 = (org.apache.lucene.document.Document)o2;
		    	
		    	String threadDate1 = DateField.stringToDate(d1.get("date")).toString();
		    	String threadDate2 = DateField.stringToDate(d2.get("date")).toString();
		        //Date date1 = d1.get("date");
		        //Date date2 = d2.get("date");
		    	//DateField is Lucene's class
		    	//Date is in Java util
		        Date date1 = DateField.stringToDate(d1.get("date"));
		        Date date2 = DateField.stringToDate(d2.get("date"));
		        
		        	String fromAddr1 = d1.get("fromAddress");
		        	String fromAddr2 = d2.get("fromAddress");
		        	String toAddr1 = d1.get("toAddress");
		        	String toAddr2 = d2.get("toAddress");
		        	String ccAddr1 = d1.get("ccAddress");
		        	String ccAddr2 = d2.get("ccAddress");
		        	String subj1 = d1.get("subject");
		        	String subj2 = d2.get("subject");
		        	String contents1 = d1.get("contents");
		        	String contents2 = d2.get("contents");
		        	
		        	//equal if same fromAddress, toAddress, ccAddress, subject, and contents
		        	if (fromAddr1.equals(fromAddr2) &&
		        		toAddr1.equals(toAddr2) &&
						ccAddr1.equals(ccAddr2) &&
						subj1.equals(subj2) &&
						contents1.equals(contents2))
		        		return 0;
		        	else if (date1.equals(date2)){ 
		        		//if not equal fromAddress..., but equal dates, compare fromAddress.
		        		//It is unlikely for a same person to send two different emails with
		        		//same time
		        	    return fromAddr1.compareTo(fromAddr2);	
		        	}else return date1.compareTo(date2);
		    }
		});//declared a treeset
		
		docSet.add(doc);
		
		try{
	 	    for (int j = 0; j < threadHits.length(); j++) {
			    org.apache.lucene.document.Document threadDoc = threadHits.doc(j);			    
			    docSet.add(threadDoc);			    
		    }
		}catch (Exception e) {
			System.out.println("inside deDuplicate: caught a " + e.getClass()
					+ "\n with message: " + e.getMessage());
			//return "ERROR!\n";
			e.printStackTrace();
		}
		return docSet;		
	}
	
	//compare two Luecen Documents for equality
	//
    static boolean compare2Documents(Document d1, Document d2){
    	Date date1 = DateField.stringToDate(d1.get("date"));
        Date date2 = DateField.stringToDate(d2.get("date"));
        
        String fromAddr1 = d1.get("fromAddress");
        String fromAddr2 = d2.get("fromAddress");
        String toAddr1 = d1.get("toAddress");
       	String toAddr2 = d2.get("toAddress");
       	String ccAddr1 = d1.get("ccAddress");
       	String ccAddr2 = d2.get("ccAddress");
        String subj1 = d1.get("subject");
        String subj2 = d2.get("subject");
        String contents1 = d1.get("contents");
        String contents2 = d2.get("contents");
        if (date1.equals(date2) &&
        	fromAddr1.equals(fromAddr2) &&
        	toAddr1.equals(toAddr2) &&
			ccAddr1.equals(ccAddr2) &&
			subj1.equals(subj2) &&
			contents1.equals(contents2))
       		return true;
        else return false;
    }
	
	//this method is not used by this program. It might be useful for other
	// purposes.
	//So just leave it here.
	String RankEmailSearch(Hits hits) {
		try {
			String answer = "";
			for (int i = 0; i < hits.length(); i++) {
				org.apache.lucene.document.Document doc = hits.doc(i);
				answer = answer + i + ". "
						+ DateField.stringToDate(doc.get("date")).toString()
						+ " [" + doc.get("folder") + "]:\n"
						+ doc.get("fromAddress") + " (" + doc.get("fromName")
						+ "} -> " + doc.get("toAddress") + " ("
						+ doc.get("toName") + ")\n" + "Subj: "
						+ doc.get("subject") + "\n-----\n";
				//+ doc.get("text");
			}//end for
			return answer;
		} catch (Exception e) {
			System.out.println("inside RankEmailSearch: caught a "
					+ e.getClass() + "\n with message: " + e.getMessage());
			return "ERROR!\n";
		}//end try
	}//end RankEmailSearch

	//get first dozens of words (about 100-ish chars) from a wholeString
	//This method is not used in this program.
	String getSurrogate(String wholeString) {
		int index = 100;
		if (wholeString.length() <= index + 1)
			return wholeString;
		else {
			char ch = wholeString.charAt(index);
			//while (ch != ' ' && ch != '\0'){
			while (ch != ' ' && index > 1) {
				index--;
				ch = wholeString.charAt(index);
			}
			return wholeString.substring(0, index + 1) + "...";
		}
	}

}