/*
 *    SimpleGraphicalClient.java
 *    Copyright (C) 2001 New Zealand Digital Library Project
 *
 *    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 2 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, write to the Free Software
 *    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */
package org.nzdl.gsdl.SimpleGraphicalClient;

import java.awt.*;
import java.awt.event.*;
import java.io.*;
import java.io.IOException;
import java.util.*;
import javax.swing.*;
import javax.swing.event.*;
import javax.swing.text.*;
import javax.swing.text.html.*; 


// local libraries
import org.nzdl.gsdl.service.NzdlCollectionInfo; 
import org.nzdl.gsdl.service.NzdlQuery;
import org.nzdl.gsdl.service.NzdlRequest;
import org.nzdl.gsdl.service.NzdlResponse;
import org.nzdl.gsdl.service.NzdlResultSet;
import org.nzdl.gsdl.service.NzdlService;
import org.nzdl.gsdl.service.NzdlServiceClient;
import org.nzdl.gsdl.util.NzdlPreferences;


/**
 * A Class representing the Panel in which the Querying action happens. 
 *
 * Does most of the actual `work' in the package.
 * 
 * @author Dave Nichols (daven@cs.waikato.ac.nz)
 * @author stuart yeates (say1@cs.waikato.ac.nz)
 * @version $Revision: 2195 $
 * @see org.nzdl.gsdl.service.SimpleGraphicalClient.SimpleGraphicalClient
 * @see org.nzdl.gsdl.service.SimpleGraphicalClient.CSModel
 * @see javax.swing.JPanel
 */

public class SearchPanel extends JPanel implements ActionListener, Constants
{

  CSModel csModel;
  NzdlService nzdl;

  JLabel collectionLabel;
  JButton collectionInfoButton;  
  JTextField searchTextField;
  JButton searchButton;
  JComboBox collectionList;  
  JPanel queryFormulationPanel, resultsPanel, dataPanel; 
  JPanel collectionListPanel, searchTextFieldPanel, searchButtonPanel;
  JList   resultsList;   
  JScrollPane scrollResultsPane;
  JScrollPane scrollDataPane;
  JFrame windowParent;
    //JEditorPane documentPane;
    JTextPane documentPane; // make this a JTextComponent ??
    JTextArea documentArea;
    JTextComponent documentComponent;
    HTMLEditorKit htmlEditorKit = new HTMLEditorKit();
    StyledEditorKit styledEditorKit = new StyledEditorKit();
    GMLDocument htmlDoc = new GMLDocument();
    DefaultStyledDocument defaultStyledDoc = new DefaultStyledDocument();
    final static GMLDocument blankDoc = new GMLDocument();
  
    /**
   * Construct and initialise a new SearchPanel
   */

  public SearchPanel( CSModel newCsModel, JFrame parent) 
  {
    super();
    windowParent = parent;
    csModel = newCsModel;
    nzdl = csModel.getNzdlService();
    setLayout( new BoxLayout(this, BoxLayout.Y_AXIS));
    setBorder(BorderFactory.createTitledBorder("Search"));
	
	
    searchTextField = new JTextField("Enter search terms here", 35) { 
	public boolean isRequestFocusEnabled(){ 
	  return true; 
	}
      };
    searchTextField.setText("Enter search terms here");
    searchTextField.setFont(searchTextFieldFont);
    searchTextField.setColumns(35);
    searchTextField.setBorder(BorderFactory.createEmptyBorder(5,5,5,5));
    searchButton = new JButton("Search");
	
    searchButton.addActionListener(this);
    //searchButton.setBorder(BorderFactory.createEmptyBorder(2,2,2,2));
    searchButton.setPreferredSize(new Dimension(80, 20));
	
    collectionListPanel = new JPanel();
    collectionListPanel.setBorder(BorderFactory.createEmptyBorder(5,5,5,5));
    collectionListPanel.setLayout(new FlowLayout(FlowLayout.LEFT));
    collectionLabel = new JLabel("Collection: ");

    collectionList = new JComboBox(csModel.getCollectionList()){
	public boolean isFocusTraversable() {
	  return false;
	}
      };
    collectionInfoButton = new JButton("Info...");
    collectionInfoButton.addActionListener(this);

    collectionListPanel.add(collectionLabel);
    collectionListPanel.add(collectionList);
    collectionListPanel.add(collectionInfoButton);

    searchTextFieldPanel = new JPanel();
    searchTextFieldPanel.setLayout(new FlowLayout(FlowLayout.LEFT));
    searchTextFieldPanel.add(searchTextField);
	
    searchButtonPanel = new JPanel();
    searchButtonPanel.setLayout(new FlowLayout(FlowLayout.RIGHT));
    searchButtonPanel.add(searchButton);
	
    queryFormulationPanel = new JPanel();
    queryFormulationPanel.setBorder(BorderFactory.createEmptyBorder(5,5,5,5));
    queryFormulationPanel.setLayout(new BoxLayout(queryFormulationPanel, BoxLayout.Y_AXIS));
    queryFormulationPanel.add(Box.createHorizontalStrut(100));
    queryFormulationPanel.add(collectionListPanel);
    queryFormulationPanel.add(searchTextFieldPanel);
    queryFormulationPanel.add(searchButtonPanel);
	
    resultsPanel = new JPanel();
    resultsPanel.setLayout(new BorderLayout());
    resultsPanel.setBorder(BorderFactory.createEmptyBorder(5,5,5,5));
    ResultModel resultListModel = csModel.getResultsModel();
    resultsList = new JList(resultListModel); 
    resultsList.setFont(resultsFont);
    resultsList.setBorder(BorderFactory.createEmptyBorder(5,5,5,5));
    resultsList.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
    scrollResultsPane = new JScrollPane(resultsList);
    resultsPanel.add(scrollResultsPane, BorderLayout.CENTER);
    csModel.addResult(Result.INITIAL_FAKE_RESULT);
	
    dataPanel = new JPanel();
    dataPanel.setLayout(new BorderLayout());
    dataPanel.setBorder(BorderFactory.createEmptyBorder(3,3,3,3));
    documentPane = new JTextPane() { // to control scrolling for raw text docs
                           public boolean getScrollableTracksViewportWidth() { 
                           if (getSize().width < getParent().getSize().width)
			        return true; 
                           else return false; 
                           } 
                           public void setSize(Dimension d) { 
                           if (d.width < getParent().getSize().width) 
			        d.width = getParent().getSize().width; 
                                super.setSize(d); 
                           } 
	}; // end custom JTextPane
    documentPane.setEditable(false);
    documentPane.setFont(docFont);
    documentPane.setBorder(BorderFactory.createEmptyBorder(5,5,5,5));
    //documentPane.setPreferredSize(new Dimension(100, 100));

    scrollDataPane = new JScrollPane(documentPane);
    scrollDataPane.setPreferredSize(new Dimension(300, 300));
    dataPanel.add(scrollDataPane, BorderLayout.CENTER);
    
    parent.getRootPane().setDefaultButton(searchButton);

    resultsList.addListSelectionListener(new ResultListSelectionHandler() );

    add(Box.createHorizontalStrut(400));
    add(queryFormulationPanel);
    add(resultsPanel);
    add(dataPanel);
    searchTextField.requestFocus();
  }

  /** respond to the user pressing the Search button */

  public void actionPerformed(ActionEvent e) {
    if (e.getSource() == searchButton ) { //assume only searchButton generates events
	// cursor not set when RETURN pressed, only when button clicked ?
      windowParent.setCursor(Cursor.getPredefinedCursor(Cursor.WAIT_CURSOR));
      //System.err.println("set wait cursor..");
      String queryString = searchTextField.getText();
      String collectionName = collectionList.getSelectedItem().toString();
      System.err.println("Search started (" + collectionName + "): \"" + queryString + "\" ..." );
      //send query to collection
      NzdlQuery nzdlQuery = new NzdlQuery(queryString);
      // return the first numResults that match
      //query.setEndResults( 15 );
      // "-1" means consider all the documents that match
      nzdlQuery.setMaxDocs( -1 );
      NzdlRequest request = new NzdlRequest( nzdlQuery );
      NzdlResponse response = new NzdlResponse();
      
      nzdl.service( collectionName, request, response );
     Date t8 = new Date();
      NzdlResultSet results = response.getResultSet();
      ArrayList docIDs = new ArrayList(results.getDocumentIDs());
      // System.err.println("Size of docIDs = " + docIDs.size());
      // paired collection of docIDs and Titles - but as Sets!
      Map titleMetaData = csModel.getNzdlService().getMetaData( collectionName, docIDs, "Title" );
      // created a paired collection of docIDs and Titles - as simple Strings!
      HashMap titleMap = new HashMap();
      for (ListIterator i = docIDs.listIterator(); i.hasNext(); ) {
	String docID = (String) i.next();
	//Set titleSet = (Set) titleMetaData.get( docID );
	ArrayList titleList = new ArrayList((Set)titleMetaData.get(docID));
	// use the first title as *the* title
	titleMap.put(docID, titleList.get(0)); 
      } // end for
      Date t9 = new Date();
      long sdiff = t9.getTime() - t8.getTime();
      System.err.println("processing results = " + sdiff + " ms");
      // update the results list
      csModel.clearResults();
      
      if (docIDs.size() == 0 ) { // give some feedback for 0 results
	csModel.addResult(Result.FAKE_RESULT);
	//documentPane.setText("");
	documentPane.setStyledDocument(blankDoc);
      }
      else { // there are some results
	Iterator docIDsIterator = docIDs.iterator();
	while (docIDsIterator.hasNext()) {
	  String resultDocID =  (String) docIDsIterator.next();
	  csModel.addResult(new Result((String)titleMap.get(resultDocID), resultDocID, collectionName ));
	} //end while
	if (NzdlPreferences.getInstance().getBoolean(Constants.DISPLAY_FIRST_DOC))
	resultsList.setSelectedIndex(0); // should be under Preference control!
      } // end else
      titleMap.clear();
      titleMetaData.clear();
      docIDs.clear();
      windowParent.setCursor(Cursor.getPredefinedCursor(Cursor.DEFAULT_CURSOR));
    } // end if
    else {
	if (e.getSource() == collectionInfoButton) {
	    //System.err.println("colllection info button pressed");
	    CollectionInfoDialog cid = new CollectionInfoDialog(windowParent, collectionList.getSelectedItem().toString(), csModel);
	}
	else {
	    System.err.println("unknown Action event in SearchPanel");
	}
    }
  } //end actionPerformed

  /** handles selection events in the results list so that when the 
      user selects a new title (say) the document contents is 
      automatically displayed in the main panel */

  class ResultListSelectionHandler implements ListSelectionListener {

      // private Result previousSelection = null;

    public void valueChanged(ListSelectionEvent e) {
      // get the result object from the SelectedIndex
      // assume we only get here with events from resultsList
      if (e.getValueIsAdjusting()) { return; }
      Result result =  (Result) resultsList.getSelectedValue();
      // System.err.println("result = " + result);
      // System.err.println("fake result = " + Result.FAKE_RESULT);
      if ((result == Result.FAKE_RESULT) || (result == Result.INITIAL_FAKE_RESULT)) {
	  //documentPane.setText("");
	  documentPane.setStyledDocument( blankDoc );
	  System.err.println("clicked on fake result");
      }
      else {
 // a real result representing a real document to deal with

	  windowParent.setCursor(Cursor.getPredefinedCursor(Cursor.WAIT_CURSOR));
	  //trash the old htmlDoc for memory/garbage collection
	  try {
	    if (htmlDoc != null)
	      htmlDoc.remove(0, htmlDoc.getLength());
	    if (defaultStyledDoc != null)
		defaultStyledDoc.remove(0, defaultStyledDoc.getLength());
	  } catch (Exception exception) {
	    throw new Error (exception.toString());
	  }
	  defaultStyledDoc = new DefaultStyledDocument();
	  htmlDoc = new GMLDocument(); 

	  try { // get the document 
	      String docContents = csModel.getNzdlService().getDocument(result.getCollectionName(),  result.getDocID());
	       StringReader sr = new StringReader( docContents);
	       if (NzdlPreferences.getInstance().getBoolean(Constants.RAW_TEXT)) { // display the document as raw text
		   documentPane.setEditorKit(styledEditorKit);
		   styledEditorKit.read( sr, defaultStyledDoc, 0);
		   documentPane.setDocument(defaultStyledDoc);
	       }
	       else { // treat as HTML
		   documentPane.setEditorKit(htmlEditorKit);
		   htmlEditorKit.read( sr, htmlDoc, 0);
		   documentPane.setStyledDocument( htmlDoc );
	       }
		   // htmlEditorKit.read( new StringReader(csModel.getNzdlService().getDocument(result.getCollectionName(),  result.getDocID())), htmlDoc, 0);
	       }
	  catch(BadLocationException badLocException)
	  {
	  System.err.println("Bad Location Exception in creating HTML doc" + badLocException);
	  }
	  catch(IOException ioException)
	  {
	      System.err.println("IO Exception whilst reading doc contents" + ioException);
	  } 

	  //documentPane.setStyledDocument( htmlDoc );
	  // should check for empty document here
	  documentPane.setCaretPosition(1);
	  // we might not be using htmlDoc at this point!!
	  htmlDoc.getImageData(nzdl, result.getCollectionName());
	  windowParent.setCursor(Cursor.getPredefinedCursor(Cursor.DEFAULT_CURSOR));
	  //System.err.println("prefix = " + nzdl.getCollectionInfo(result.getCollectionName()).getHTTPPrefix());
      }
    } //end valueChanged
  }//end ResultListSelectionHandler

} //end SearchPanel