/* *************************************************************************
 
 IT Mill Toolkit 

 Development of Browser User Interfaces Made Easy

 Copyright (C) 2000-2006 IT Mill Ltd
 
 *************************************************************************

 This product is distributed under commercial license that can be found
 from the product package on license.pdf. Use of this product might 
 require purchasing a commercial license from IT Mill Ltd. For guidelines 
 on usage, see licensing-guidelines.html

 *************************************************************************
 
 For more information, contact:
 
 IT Mill Ltd                           phone: +358 2 4802 7180
 Ruukinkatu 2-4                        fax:   +358 2 4802 7181
 20540, Turku                          email:  info@itmill.com
 Finland                               company www: www.itmill.com
 
 Primary source for information and releases: www.itmill.com

 ********************************************************************** */

package com.itmill.toolkit.ui;

import java.lang.reflect.Method;
import java.util.Hashtable;
import java.util.LinkedList;
import java.util.Iterator;
import java.util.Map;

import com.itmill.toolkit.terminal.*;

/**
 * Tabsheet component.
 * 
 * @author IT Mill Ltd.
 * @version
 * @VERSION@
 * @since 3.0
 */
public class TabSheet extends AbstractComponentContainer implements Sizeable {

	/**
	 * Use this stylename with {@link #addStyleName(String)} to remove padding
	 * between TabSheet borders and content. The actual client-side implementation
	 * will determine which stylenames it implements.
	 */
	public static final String STYLE_NO_PADDING = "nopad";

	/**
	 * Linked list of component tabs.
	 */
	private LinkedList tabs = new LinkedList();

	/**
	 * Tab -> caption mapping.
	 */
	private Hashtable tabCaptions = new Hashtable();

	/**
	 * Tab -> icon mapping .
	 */
	private Hashtable tabIcons = new Hashtable();

	/**
	 * Selected tab.
	 */
	private Component selected = null;

	private KeyMapper keyMapper = new KeyMapper();

	/**
	 * Holds the value of property tabsHIdden.
	 */
	private boolean tabsHidden;

	private int height = -1;

	private int heightUnit;

	private int width = -1;

	private int widthUnit;

	/**
	 * Constructs a new Tabsheet. Tabsheet is immediate by default.
	 */
	public TabSheet() {
		super();
		setImmediate(true);
	}

	/**
	 * Gets the component container iterator for going trough all the components
	 * in the container.
	 * 
	 * @return the Iterator of the components inside the container.
	 */
	public Iterator getComponentIterator() {
		return java.util.Collections.unmodifiableList(tabs).iterator();
	}

	/**
	 * Removes the component from this container.
	 * 
	 * @param c
	 *            the component to be removed.
	 */
	public void removeComponent(Component c) {
		if (c != null && tabs.contains(c)) {
			super.removeComponent(c);
			keyMapper.remove(c);
			tabs.remove(c);
			tabCaptions.remove(c);
			if (c.equals(selected)) {
				if (tabs.isEmpty())
					selected = null;
				else {
					selected = (Component) tabs.getFirst();
					fireSelectedTabChange();
				}
			}
			requestRepaint();
		}
	}

	/**
	 * Adds the component into this container. The component is added as a tab
	 * where its default tab-caption is the caption of the component.
	 * 
	 * @param c
	 *            the component to be added.
	 */
	public void addComponent(Component c) {
		addTab(c, c.getCaption(), getIcon());
	}

	/**
	 * Adds the new tab into TabSheet.
	 * 
	 * @param c
	 *            the component to be added onto tab.
	 * @param caption
	 *            the caption of the tab.
	 * @param icon
	 *            the Set the icon of the tab.
	 */
	public void addTab(Component c, String caption, Resource icon) {
		if (c != null) {
			tabs.addLast(c);
			tabCaptions.put(c, caption != null ? caption : "");
			if (icon != null)
				tabIcons.put(c, icon);
			if (selected == null) {
				selected = c;
				fireSelectedTabChange();
			}
			super.addComponent(c);
			requestRepaint();
		}
	}

	/**
	 * Gets the component UIDL tag.
	 * 
	 * @return the Component UIDL tag as string.
	 */
	public String getTag() {
		return "tabsheet";
	}

	/**
	 * Moves all components from another container to this container. The
	 * components are removed from the other container.
	 * 
	 * @param source
	 *            the container components are removed from.
	 */
	public void moveComponentsFrom(ComponentContainer source) {
		for (Iterator i = source.getComponentIterator(); i.hasNext();) {
			Component c = (Component) i.next();
			String caption = null;
			Resource icon = null;
			if (TabSheet.class.isAssignableFrom(source.getClass())) {
				caption = ((TabSheet) source).getTabCaption(c);
				icon = ((TabSheet) source).getTabIcon(c);
			}
			source.removeComponent(c);
			addTab(c, caption, icon);

		}
	}

	/**
	 * Paints the content of this component.
	 * 
	 * @param event
	 *            the Paint Event.
	 * @throws PaintException
	 *             if the paint operation failed.
	 */
	public void paintContent(PaintTarget target) throws PaintException {

		if (areTabsHidden())
			target.addAttribute("hidetabs", true);

		if (width > -1) {
			target.addAttribute("width", getWidth() + UNIT_SYMBOLS[widthUnit]);
		}
		if (height > -1) {
			target.addAttribute("height", getHeight()
					+ UNIT_SYMBOLS[heightUnit]);
		}

		target.startTag("tabs");

		for (Iterator i = getComponentIterator(); i.hasNext();) {
			Component c = (Component) i.next();
			if (!c.isVisible())
				continue;
			target.startTag("tab");
			Resource icon = getTabIcon(c);
			if (icon != null)
				target.addAttribute("icon", icon);
			String caption = getTabCaption(c);
			if (!c.isEnabled()) {
				target.addAttribute("disabled", true);
			}

			if (caption != null && caption.length() > 0)
				target.addAttribute("caption", caption);
			target.addAttribute("key", keyMapper.key(c));
			if (c.equals(selected)) {
				target.addAttribute("selected", true);
				c.paint(target);
			}
			target.endTag("tab");
		}

		target.endTag("tabs");

		if (selected != null)
			target.addVariable(this, "selected", keyMapper.key(selected));
	}

	/**
	 * Are tabs hidden.
	 * 
	 * @return the Property visibility.
	 */
	public boolean areTabsHidden() {
		return this.tabsHidden;
	}

	/**
	 * Setter for property tabsHidden.
	 * 
	 * @param tabsHidden
	 *            True if the tabs should be hidden.
	 */
	public void hideTabs(boolean tabsHidden) {
		this.tabsHidden = tabsHidden;
		requestRepaint();
	}

	/**
	 * Gets the caption for a component.
	 * 
	 * @param c
	 *            the component.
	 */
	public String getTabCaption(Component c) {
		String caption = (String) tabCaptions.get(c);
		if (caption == null)
			caption = "";
		return caption;
	}

	/**
	 * Sets the caption for a component.
	 * 
	 * @param c
	 *            the component.
	 * @param caption
	 *            the caption to set.
	 */
	public void setTabCaption(Component c, String caption) {
		tabCaptions.put(c, caption);
		requestRepaint();
	}

	/**
	 * Gets the icon for a component.
	 * 
	 * @param c
	 *            the component.
	 */
	public Resource getTabIcon(Component c) {
		return (Resource) tabIcons.get(c);
	}

	/**
	 * ] Sets the icon for a component.
	 * 
	 * @param c
	 * @param icon
	 */
	public void setTabIcon(Component c, Resource icon) {
		if (icon == null)
			tabIcons.remove(c);
		else
			tabIcons.put(c, icon);
		requestRepaint();
	}

	/**
	 * Sets the selected tab.
	 * 
	 * @param c
	 */
	public void setSelectedTab(Component c) {
		if (c != null && tabs.contains(c) && !selected.equals(c)) {
			selected = c;
			fireSelectedTabChange();
			requestRepaint();
		}
	}

	/**
	 * Gets the selected tab.
	 * 
	 * @return the selected tab.
	 */
	public Component getSelectedTab() {
		return selected;
	}

	/**
	 * Invoked when the value of a variable has changed.
	 * 
	 * @see com.itmill.toolkit.ui.AbstractComponent#changeVariables(java.lang.Object,
	 *      java.util.Map)
	 */
	public void changeVariables(Object source, Map variables) {
		if (variables.containsKey("selected"))
			setSelectedTab((Component) keyMapper.get((String) variables
					.get("selected")));
	}

	/* Documented in superclass */
	public void replaceComponent(Component oldComponent, Component newComponent) {

		// Gets the captions
		String oldCaption = getTabCaption(oldComponent);
		Resource oldIcon = getTabIcon(oldComponent);
		String newCaption = getTabCaption(newComponent);
		Resource newIcon = getTabIcon(newComponent);

		// Gets the locations
		int oldLocation = -1;
		int newLocation = -1;
		int location = 0;
		for (Iterator i = tabs.iterator(); i.hasNext();) {
			Component component = (Component) i.next();

			if (component == oldComponent)
				oldLocation = location;
			if (component == newComponent)
				newLocation = location;

			location++;
		}

		if (oldLocation == -1)
			addComponent(newComponent);
		else if (newLocation == -1) {
			removeComponent(oldComponent);
			keyMapper.remove(oldComponent);
			addComponent(newComponent);
			tabs.remove(newComponent);
			tabs.add(oldLocation, newComponent);
			setTabCaption(newComponent, oldCaption);
			setTabIcon(newComponent, oldIcon);
		} else {
			if (oldLocation > newLocation) {
				tabs.remove(oldComponent);
				tabs.add(newLocation, oldComponent);
				tabs.remove(newComponent);
				tabs.add(oldLocation, newComponent);
			} else {
				tabs.remove(newComponent);
				tabs.add(oldLocation, newComponent);
				tabs.remove(oldComponent);
				tabs.add(newLocation, oldComponent);
			}
			setTabCaption(newComponent, oldCaption);
			setTabIcon(newComponent, oldIcon);
			setTabCaption(oldComponent, newCaption);
			setTabIcon(oldComponent, newIcon);

			requestRepaint();
		}
	}

	/* Click event ************************************************ */

	private static final Method SELECTED_TAB_CHANGE_METHOD;
	static {
		try {
			SELECTED_TAB_CHANGE_METHOD = SelectedTabChangeListener.class
					.getDeclaredMethod("selectedTabChange",
							new Class[] { SelectedTabChangeEvent.class });
		} catch (java.lang.NoSuchMethodException e) {
			// This should never happen
			throw new java.lang.RuntimeException();
		}
	}

	/**
	 * Selected Tab Change event. This event is thrown, when the selected tab in
	 * the tab sheet is changed.
	 * 
	 * @author IT Mill Ltd.
	 * @version
	 * @VERSION@
	 * @since 3.0
	 */
	public class SelectedTabChangeEvent extends Component.Event {

		/**
		 * Serial generated by eclipse.
		 */
		private static final long serialVersionUID = 3258129141914940469L;

		/**
		 * New instance of selected tab change event
		 * 
		 * @param source
		 *            the Source of the event.
		 */
		public SelectedTabChangeEvent(Component source) {
			super(source);
		}

		/**
		 * Select where the event occurred
		 * 
		 * @return the Source of the event.
		 */
		public Select getSelect() {
			return (Select) getSource();
		}
	}

	/**
	 * Selected Tab Change Event listener
	 * 
	 * @author IT Mill Ltd.
	 * 
	 * @version
	 * @VERSION@
	 * @since 3.0
	 */
	public interface SelectedTabChangeListener {

		/**
		 * Visible tab in tab sheet has has been changed.
		 * 
		 * @param event
		 *            the Selected tab change event.
		 */
		public void selectedTabChange(SelectedTabChangeEvent event);
	}

	/**
	 * Adds the selected tab change listener
	 * 
	 * @param listener
	 *            the Listener to be added.
	 */
	public void addListener(SelectedTabChangeListener listener) {
		addListener(SelectedTabChangeEvent.class, listener,
				SELECTED_TAB_CHANGE_METHOD);
	}

	/**
	 * Removes the selected tab change listener
	 * 
	 * @param listener
	 *            the Listener to be removed.
	 */
	public void removeListener(SelectedTabChangeListener listener) {
		removeListener(SelectedTabChangeEvent.class, listener,
				SELECTED_TAB_CHANGE_METHOD);
	}

	/**
	 * Emits the options change event.
	 */
	protected void fireSelectedTabChange() {
		fireEvent(new SelectedTabChangeEvent(this));
	}

	public int getHeight() {
		return height;
	}

	public int getHeightUnits() {
		return heightUnit;
	}

	public int getWidth() {
		return width;
	}

	public int getWidthUnits() {
		return widthUnit;
	}

	public void setHeight(int height) {
		this.height = height;
		requestRepaint();
	}

	public void setHeightUnits(int units) {
		this.heightUnit = units;
		requestRepaint();
	}

	public void setWidth(int width) {
		this.width = width;
		requestRepaint();
	}

	public void setWidthUnits(int units) {
		this.widthUnit = units;
		requestRepaint();
	}
}