/*

* Copyright (c) 2009 Nokia Corporation and/or its subsidiary(-ies).

* All rights reserved.

* This component and the accompanying materials are made available

* under the terms of "Eclipse Public License v1.0"

* which accompanies this distribution, and is available

* at the URL "http://www.eclipse.org/legal/epl-v10.html".

*

* Initial Contributors:

* Nokia Corporation - initial contribution.

*

* Contributors:

*

* Description:

*

*/

package javax.microedition.lcdui;

import java.util.*;

import javax.microedition.lcdui.EventDispatcher.LCDUIEvent;

import org.eclipse.swt.SWT;

import org.eclipse.swt.events.SelectionEvent;

import org.eclipse.swt.events.SelectionListener;

import org.eclipse.swt.widgets.*;

/**

 * This class represents LCDUI Form.

 */

public class Form extends Screen

{

    /**

     * Abstract layouting policy.

     */

    private FormLayouter formLayouter;

    /**

     * Item vector.

     */

    private Vector items = new Vector();

    /**

     * Item state listener.

     */

    private ItemStateListener itemStateListener;

    private int startIndex;

    private FormTimerTask formTimerTask;

    private Timer layoutTimer = new Timer();

    // private FormMouseListener mouseListener = new FormMouseListener();

    private FormScrollBarListener fsbl = new FormScrollBarListener();

    /**

     * ScrolledComposite represents Form

     */

    private ScrolledComposite formComposite;

    /**

     * Constructor.

     *

     * @param title the title string

     */

    public Form(String title)

    {

        super(title);

        construct();

        formLayouter = new FormLayouter(this);

    }

    /**

     * Constructor.

     *

     * @param title the title string

     * @param formItems array of items on the formComposite

     */

    public Form(String title, Item[] formItems)

    {

        this(title);

        if(formItems != null)

        {

            for(int i = 0; i < formItems.length; i++)

            {

                this.append(formItems[i]);

            }

        }

    }

    /* (non-Javadoc)

     * @see javax.microedition.lcdui.Displayable#eswtConstructContent(int)

     */

    Composite eswtConstructContent(int style)

    {

        Composite comp = super.eswtConstructContent(SWT.VERTICAL);

        ScrollBar vBar = comp.getVerticalBar();

        if(vBar != null)

        {

            vBar.setVisible(true);

            vBar.setEnabled(true);

        }

        formComposite = new ScrolledComposite(comp, SWT.NONE);

        return comp;

    }

    /* (non-Javadoc)

     * @see Displayable#eswtHandleShowCurrentEvent()

     */

    void eswtHandleShowCurrentEvent()

    {

        super.eswtHandleShowCurrentEvent();

        ScrollBar vBar = getContentComp().getVerticalBar();

        if(vBar != null)

        {

            vBar.addSelectionListener(fsbl);

        }

        formLayouter.handleShowCurrentEvent();

    }

    /* (non-Javadoc)

     * @see Displayable#eswtHandleHideCurrentEvent()

     */

    void eswtHandleHideCurrentEvent()

    {

        super.eswtHandleHideCurrentEvent();

        ScrollBar vBar = getContentComp().getVerticalBar();

        if(vBar != null)

        {

            vBar.removeSelectionListener(fsbl);

        }

        formLayouter.handleHideCurrentEvent();

    }

    /* (non-Javadoc)

     * @see Displayable#eswtHandleResizeEvent(int, int)

     */

    void eswtHandleResizeEvent(int width, int height)

    {

        super.eswtHandleResizeEvent(width, height);

        if(formComposite != null)

        {

            formComposite.setRedraw(false);

            formComposite.setOrigin(0, 0, true);

            formComposite.setSize(width, height);

            formComposite.setRedraw(true);

            formLayouter.handleResizeEvent(width, height);

            resetLayoutTimer(0);

        }

    }

    /**

     * Handle key and traverse events.

     *

     * @param e eSWT event

     */

    void eswtHandleEvent(Event e)

    {

        super.eswtHandleEvent(e);

        if(e.type == SWT.Traverse)

        {

            e.doit = false;

        }

        else

        {

            formLayouter.handleKeyEvent(e.keyCode, e.type);

        }

    }

    /**

     * Append Item to a Form.

     *

     * @param item Item to append to a Form.

     * @return index of Item in Form

     */

    public int append(Item item)

    {

        if(item == null)

        {

            throw new NullPointerException(

                MsgRepository.FORM_EXCEPTION_ITEM_NULL_POINTER);

        }

        if(item.getParent() != null)

        {

            throw new IllegalStateException(

                MsgRepository.FORM_EXCEPTION_ITEM_OWNED_BY_CONTAINER);

        }

        int returnValue = -1;

        synchronized(formLayouter)

        {

            item.setParent(this);

            items.addElement(item);

            returnValue = items.indexOf(item);

            resetLayoutTimer(returnValue);

        }

        return returnValue;

    }

    /**

     * Append StringItem to a Form.

     *

     * @param text - text for StringItem.

     * @return index of StringITem in a Form.

     */

    public int append(String text)

    {

        if(text == null)

        {

            throw new NullPointerException(

                MsgRepository.FORM_EXCEPTION_STRING_NULL_POINTER);

        }

        return append(new StringItem(null, text, Item.LAYOUT_DEFAULT));

    }

    /**

     * Append ImageItem to a Form.

     *

     * @param img - Image for ImageItem.

     * @return index of ImageItem in a Form.

     */

    public int append(Image img)

    {

        if(img == null)

        {

            throw new NullPointerException(

                MsgRepository.FORM_EXCEPTION_IMAGE_NULL_POINTER);

        }

        return append(new ImageItem(null, img, Item.LAYOUT_DEFAULT, null));

    }

    /**

     * Insert item into Form before Item in specified position.

     *

     * @param position index where to insert.

     * @param item item insert.

     * @throws IndexOutOfBoundsException if position is incorrect.

     */

    public void insert(int position, Item item)

    {

        if(item == null)

        {

            throw new NullPointerException(

                MsgRepository.FORM_EXCEPTION_ITEM_NULL_POINTER);

        }

        if(item.getParent() != null)

        {

            throw new IllegalStateException(

                MsgRepository.FORM_EXCEPTION_ITEM_OWNED_BY_CONTAINER);

        }

        if ((position < 0) || (position > items.size() )) 

        {

            throw new IndexOutOfBoundsException(

                MsgRepository.FORM_EXCEPTION_INVALID_ITEM_INDEX);

        }

        synchronized(formLayouter)

        {

            item.setParent(this);

            items.insertElementAt(item, position);

            resetLayoutTimer(items.indexOf(item));

        }

    }

    /**

     * Delete item with index itemNumber from the formComposite.

     *

     * @param position - index of Item to delete from Form.

     * @throws IndexOutOfBoundsException if position is incorrect.

     */

    public void delete(int position)

    {

        if((position < 0) || (position > (items.size() - 1)))

        {

            throw new IndexOutOfBoundsException(

                MsgRepository.FORM_EXCEPTION_INVALID_ITEM_INDEX);

        }

        synchronized(formLayouter)

        {

        	Item item = ((Item) items.elementAt(position));

            item.clearParent();

        	formLayouter.removeLayoutObject(item);			

            items.removeElementAt(position);

            resetLayoutTimer(position - 1);

        }

    }

    /**

     * Delete all items from the formComposite.

     */

    public void deleteAll()

    {

        synchronized(formLayouter)

        {

            for(int i = 0; i < items.size(); i++)

            {

	        	Item item = ((Item) items.elementAt(i));

                item.clearParent();

	        	formLayouter.removeLayoutObject(item);

            }

            items.removeAllElements();

            resetLayoutTimer(0);

        }

    }

    /**

     * Set the item to the formComposite, replacing the item on newItem index.

     *

     * @param position index of Item to replace.

     * @param newItem new item to set.

     * @throws IndexOutOfBoundsException if position is incorrect.

     */

    public void set(int position, Item newItem)

    {

        if(newItem == null)

        {

            throw new NullPointerException(

                MsgRepository.FORM_EXCEPTION_ITEM_NULL_POINTER);

        }

        if(newItem.getParent() != null)

        {

            throw new IllegalStateException(

                MsgRepository.FORM_EXCEPTION_ITEM_OWNED_BY_CONTAINER);

        }

        if((position < 0) || (position > (items.size() - 1)))

        {

            throw new IndexOutOfBoundsException(

                MsgRepository.FORM_EXCEPTION_INVALID_ITEM_INDEX);

        }

        synchronized(formLayouter)

        {

            newItem.setParent(this);

            // clear reference to a form for "old" item.

            Item oldItem = get(position);

			oldItem.clearParent();

			formLayouter.removeLayoutObject(oldItem);

            items.setElementAt(newItem, position);

            resetLayoutTimer(position);

        }

    }

    /**

     * Return Item with specified index in the vector.

     *

     * @param position index of item.

     * @return Item - specified by position

     * @throws IndexOutOfBoundsException if position is incorrect.

     */

    public Item get(int position)

    {

        Item returnItem = null;

        synchronized(formLayouter)

        {

            try

            {

                returnItem = (Item) items.elementAt(position);

            }

            catch(ArrayIndexOutOfBoundsException e)

            {

                throw new IndexOutOfBoundsException(e.getMessage());

            }

        }

        return returnItem;

    }

    /**

     * Get number of items in the formComposite.

     *

     * @return number of Items in Form.

     */

    public int size()

    {

        return items.size();

    }

    /**

     * Set ItemStateListener.

     *

     * @param itemStateListener New ItemStateListener.

     */

    public void setItemStateListener(ItemStateListener itemStateListener)

    {

        this.itemStateListener = itemStateListener;

    }

    /**

     * Scrolls form so that specified item is visible and if possible transfers

     * focus to it.

     *

     * @param item The Item which should be set visible.

     */

    void setCurrentItem(Item item)

    {

        formLayouter.setCurrentItem(item);

    }

    /**

     * Notify item state listener about state change.

     *

     * @param item which triggered this event.

     */

    void notifyItemStateChanged(final Item item)

    {

        if(item != null && item.getParent() == this)

        {

            if(itemStateListener != null)

            {

                ESWTUIThreadRunner.getInstance().getDisplay().asyncExec(

                    new Runnable()

                {

                    public void run()

                    {

                        itemStateListener.itemStateChanged(item);

                    }

                });

            }

        }

    }

    /**

     * Update item state in form.

     *

     * @param item

     * @param updateReason

     * @param param additional parameter

     */

	void updateItemState(Item item, int updateReason, Object param)

	{

		if(item != null && item.getParent() == this)

		{

			if(layoutTimer != null)

			{

				formLayouter.updateItemState(item, updateReason, param);

			}

			if((updateReason & Item.UPDATE_SIZE_CHANGED) != 0)

			{

				synchronized(formLayouter)

				{

					resetLayoutTimer(items.indexOf(item));

				}

			}

		}

	}

    /**

     * Get Vector of items.

     *

     * @return Vector of items

     */

    Vector getItems()

    {

        return items;

    }

    /**

     * @return ScrolledComposite which represents Form

     */

    ScrolledComposite getFormComposite()

    {

        return formComposite;

    }

    /**

     * Returns form Form Layouter.

     * @return Reference to layout policy.

     *

     */

    FormLayouter getFormLayouter()

    {

        return formLayouter;

    }

    // =========================================================================

    // TODO: remove this

    private boolean layoutLR = true;

    public Form(boolean leftRightLanguage, String title)

    {

        super(title);

        construct();

        layoutLR = leftRightLanguage;

        formLayouter = new FormLayouter(this);

    }

    // =========================================================================

    /**

     * Returns if the language Left-to-Right.

     */

    boolean getLeftRightLanguage()

    {

        return layoutLR;

    }

    /**

     * Reset timer for do layout with a given start index.

     */

    private void resetLayoutTimer(int newStartIndex)

    {

        if(layoutTimer != null)

        {

            if(formTimerTask != null)

            {