/*
 *  JFLAP - Formal Languages and Automata Package
 * 
 * 
 *  Susan H. Rodger
 *  Computer Science Department
 *  Duke University
 *  August 27, 2009

 *  Copyright (c) 2002-2009
 *  All rights reserved.

 *  JFLAP is open source software. Please see the LICENSE for terms.
 *
 */





package gui.grammar.convert;

import grammar.Grammar;
import grammar.Production;
import gui.event.SelectionEvent;
import gui.event.SelectionListener;
import javax.swing.*;
import javax.swing.event.*;
import javax.swing.table.*;

/**
 * The <CODE>GrammarViewer</CODE> is a class for the graphical non-editable
 * viewing of grammars, with an extra field for a checkbox to indicate that a
 * production has been "processed," though what exactly that means is left to
 * the context in which this component is used.
 * 
 * @author Thomas Finley
 */

public class GrammarViewer extends JTable {
	/**
	 * Instantiates a new <CODE>GrammarViewer</CODE>.
	 * 
	 * @param grammar
	 *            the grammar to display in this view
	 */
	public GrammarViewer(Grammar grammar) {
		setModel(new GrammarTableModel());
		this.grammar = grammar;
		// setLayout(new BorderLayout());
		Production[] prods = grammar.getProductions();
		data = new Object[prods.length][2];
		Object[] columnNames = { "Production", "Created" };

		for (int i = 0; i < prods.length; i++) {
			data[i][0] = prods[i];
			data[i][1] = Boolean.FALSE;
			productionToRow.put(prods[i], new Integer(i));
		}
		DefaultTableModel model = (DefaultTableModel) getModel();
		model.setDataVector(data, columnNames);

		// Set the listener to the selectedness.
		getSelectionModel().addListSelectionListener(listSelectListener);
	}

	/**
	 * Returns the <CODE>Grammar</CODE> that this <CODE>GrammarViewer</CODE>
	 * displays.
	 * 
	 * @return this viewer's grammar
	 */
	public Grammar getGrammar() {
		return grammar;
	}

	/**
	 * Adds a selection listener to this grammar viewer. The listener will
	 * receive events whenever the selection changes.
	 * 
	 * @param listener
	 *            the selection listener to add
	 */
	public void addSelectionListener(SelectionListener listener) {
		selectionListeners.add(listener);
	}

	/**
	 * Removes a selection listener from this grammar viewer.
	 * 
	 * @param listener
	 *            the selection listener to remove
	 */
	public void removeSelectionListener(SelectionListener listener) {
		selectionListeners.remove(listener);
	}

	/**
	 * Distributes a selection event.
	 */
	protected void distributeSelectionEvent() {
		java.util.Iterator it = selectionListeners.iterator();
		while (it.hasNext()) {
			SelectionListener listener = (SelectionListener) it.next();
			listener.selectionChanged(EVENT);
		}
	}

	/**
	 * Returns the currently selected productions.
	 * 
	 * @return the currently selected productions
	 */
	public Production[] getSelected() {
		int[] rows = getSelectedRows();
		Production[] selected = new Production[rows.length];
		for (int i = 0; i < rows.length; i++)
			selected[i] = (Production) data[rows[i]][0];
		return selected;
	}

	/**
	 * Sets the indicated production as either checked or unchecked
	 * appropriately.
	 * 
	 * @param production
	 *            the production to set the "checkyness" for
	 * @param checked
	 *            <CODE>true</CODE> if the production should be marked as
	 *            checked, <CODE>false</CODE> if unchecked
	 */
	public void setChecked(Production production, boolean checked) {
		Integer r = (Integer) productionToRow.get(production);
		if (r == null)
			return;
		int row = r.intValue();
		Boolean b = checked ? Boolean.TRUE : Boolean.FALSE;
		data[row][1] = b;
		((DefaultTableModel) getModel()).setValueAt(b, row, 1);
	}

	/** The grammar to display. */
	private Grammar grammar;

	/** The button group. */
	private ButtonGroup bgroup = new ButtonGroup();

	/** The data of the table. */
	private Object[][] data;

	/** The mapping of productions to a row (rows stored as Integer). */
	private java.util.Map productionToRow = new java.util.HashMap();

	/** The selection event. */
	private SelectionEvent EVENT = new SelectionEvent(this);

	/** The set of selection listeners. */
	private java.util.Set selectionListeners = new java.util.HashSet();

	private ListSelectionListener listSelectListener = new ListSelectionListener() {
		public void valueChanged(ListSelectionEvent e) {
			distributeSelectionEvent();
		}
	};

	/**
	 * The model for this table.
	 */
	private class GrammarTableModel extends DefaultTableModel {
		public boolean isCellEditable(int row, int column) {
			return false;
		}

		public Class getColumnClass(int columnIndex) {
			if (columnIndex == 1)
				return Boolean.class;
			return super.getColumnClass(columnIndex);
		}
	}
}