/*
 * Copyright (c) 2005 Einar Pehrson <einar@pehrson.nu>.
 *
 * This file is part of
 * CleanSheets - a spreadsheet application for the Java platform.
 *
 * CleanSheets 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.
 *
 * CleanSheets 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 CleanSheets; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */
package csheets.ui.ext;

import java.util.Properties;

import javax.swing.Icon;
import javax.swing.JComponent;
import javax.swing.JMenu;
import javax.swing.JToolBar;

import csheets.ext.Extension;
import csheets.ui.ctrl.UIController;

/**
 * <p>A base class for user interface extensions to the CleanSheets application.
 * Subclasses should override the accessor methods for the components that they
 * provide, and add components as selection listeners whenever required.
 * <p>A user interface extension should only create one instance of each type of
 * component, and therefore always return the same component when a given
 * method is called.
 * @see csheets.ui.ctrl.SelectionListener
 * @author Einar Pehrson
 */
public abstract class UIExtension {

        /** The name of the extension */
        protected final Extension extension;

        /** The user interface controller */
        protected final UIController uiController;

        /** The application's user properties */
        protected final Properties props;

        /**
         * Creates a new user interface extension..
         * @param extension the extension for which components are provided
         * @param uiController the user interface controller
         */
        public UIExtension(Extension extension, UIController uiController) {
                // Stores member
                this.extension = extension;
                this.uiController = uiController;
                this.props = uiController.getUserProperties();

                // Enables components according to properties
                if (getCellDecorator() != null)
                        getCellDecorator().setEnabled(Boolean.TRUE.equals(
                                getEnabledProperty("celldecorator")));
                if (getTableDecorator() != null)
                        getTableDecorator().setEnabled(Boolean.TRUE.equals(
                                getEnabledProperty("tabledecorator")));
                if (getToolBar() != null)
                        getToolBar().setVisible(Boolean.TRUE.equals(
                                getEnabledProperty("toolbar")));
                if (getSideBar() != null)
                        getSideBar().setEnabled(Boolean.TRUE.equals(
                                getEnabledProperty("sidebar")));
        }

        /**
         * Returns the extension for which this UI extension provides components.
         * @return the extension for which this UI extension provides components
         */
        public final Extension getExtension() {
                return extension;
        }

        /**
         * Returns the enabled property corresponding to the given component key.
         * @param propKey the property key of the relevant component
         * @return a Boolean value if a property is found, null otherwise
         */
        public final Boolean getEnabledProperty(String propKey) {
                String prop = props.getProperty(extension.getPropertyKey() + propKey);
                if (prop == null)
                        return null;
                else if (prop.equalsIgnoreCase("true"))
                        return true;
                else if (prop.equalsIgnoreCase("false"))
                        return false;
                else
                        return null;
        }

        /**
         * Sets the enabled property corresponding to the given component key.
         * @param propKey the property key of the relevant component
         * @param enabled whether the component should be enabled or not
         */
        public final void setEnabledProperty(String propKey, boolean enabled) {
                props.setProperty(extension.getPropertyKey() + propKey,
                        Boolean.toString(enabled));
        }

        /**
         * Returns an icon to display with the extension's name.
         * @return an icon, or null if the extension does not provide one
         */
        public Icon getIcon() {
                return null;
        }

        /**
         * Returns a cell decorator that visualizes the data added by the extension.
         * @return a cell decorator, or null if the extension does not provide one
         */
        public CellDecorator getCellDecorator() {
                return null;
        }

        /**
         * Returns a table decorator that visualizes the data added by the extension.
         * @return a table decorator, or null if the extension does not provide one
         */
        public TableDecorator getTableDecorator() {
                return null;
        }

        /**
         * Returns a menu component that gives access to extension-specific
         * functionality.
         * @return a JMenu component, or null if the extension does not provide one
         */
        public JMenu getMenu() {
                return null;
        }

        /**
         * Returns a toolbar that gives access to extension-specific
         * functionality.
         * @return a JToolBar component, or null if the extension does not provide one
         */
        public JToolBar getToolBar() {
                return null;
        }

        /**
         * Returns a side bar that gives access to extension-specific
         * functionality.
         * @return a component, or null if the extension does not provide one
         */
        public JComponent getSideBar() {
                return null;
        }
}