/*
* 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 org.eclipse.swt.graphics.Point;

/**
 * Item representing a non-editable string.
 */
public class StringItem extends Item
{
    /**
     * If StringItem is changed, reasons for Re-layouting.
     */
	static final int UPDATE_FONT = UPDATE_ITEM_MAX << 1;
	static final int UPDATE_TEXT = UPDATE_ITEM_MAX << 2;

    private String text;
    private int appearanceMode;
    private Font font;

    /**
     * Constructor, creates a new StringItem with appearance mode PLAIN.
     *
     * @param label Label of StringItem.
     * @param txt Text of StringItem.
     */
    public StringItem(String label, String txt)
    {
        this(label, txt, Item.PLAIN);
    }

    /**
     * Constructor.
     *
     * @param label Label of the item, or null if no label.
     * @param txt Textual content of the item, or null if no initial textual
     *            content.
     * @param appMode Appearance mode of this item. This must be one of the
     *            appearance modes defined in Item-class.
     * @throws IllegalArgumentException If appearance mode is not one defined in
     *             Item-class.
     */
    public StringItem(String label, String txt, int appMode)
    {
        if((appMode != Item.PLAIN) && (appMode != Item.BUTTON)
                && (appMode != Item.HYPERLINK))
        {
            throw new IllegalArgumentException(
                MsgRepository.STRINGITEM_EXCEPTION_INVALID_APPMODE);
        }

        appearanceMode = appMode;
        setLabel(label);
        setText(txt);
        font = Font.getDefaultFont();
    }

    /**
     * Gets the textual content of this item.
     *
     * @return Text of the item. Could return null if the text is empty.
     */
    public String getText()
    {
        return text;
    }

    /**
     * Sets the text of this item.
     *
     * @param newTxt Text to be set. If null, text is set to be empty.
     */
    public void setText(String newTxt)
    {
        if(newTxt == null)
        {
            text = null;
        }
        else
        {
            text = newTxt;
        }
        updateParent(UPDATE_TEXT);
    }

    /**
     * Gets current appearance mode.
     *
     * @return The one of appearance modes defined in Item-class.
     */
    public int getAppearanceMode()
    {
        return appearanceMode;
    }

    /**
     * Gives hint which font this item should use. System may ignore this
     * request.
     *
     * @param f Font to be used. If null, system will use default font for this
     *            item.
     */
    public void setFont(Font f)
    {
        font = (f == null ? Font.getDefaultFont() : f);
        updateParent(UPDATE_FONT);
    }

    /**
     * Gets font that is set by calling setFont()-method. Note that returned
     * font is not necessary the font used with this item.
     *
     * @return Font set by setFont()-method.
     */
    public Font getFont()
    {
        return font;
    }

    /* (non-Javadoc)
     * @see midp3javax.microedition.lcdui.Item#isFocusable()
     */
    boolean isFocusable()
    {
        return (getNumCommands() > 0);
    }

    /**
     * Adds command to this StringItem. If same command is already added to this item,
     * nothing happens.
     *
     * @param command A command to be added.
     * @throws NullPointerException if cmd is null.
     */
    public void addCommand(Command command)
    {
    	super.addCommand(command);
		
		if(getCommands().size() == 1)
		{
			updateParent(UPDATE_SIZE_CHANGED);
		}
    }

    /**
     * Removes command from the StringItem. If command doesn't exists in this item,
     * nothing happens.
     *
     * @param command The command to be removed.
     */
    public void removeCommand(Command command)
    {
    	super.removeCommand(command);
		
		if(getCommands().size() == 0)
		{
			updateParent(UPDATE_SIZE_CHANGED);
		}
    }

    /**
     * Calculates minimum size of this item.
     *
     * @return Minimum size.
     */
    Point calculateMinimumSize()
    {
        return StringItemLayouter.calculateMinimumBounds(this);
    }

    /**
     * Calculates preferred size of this item.
     *
     * @return Preferred size.
     */
    Point calculatePreferredSize()
    {
        return StringItemLayouter.calculatePreferredBounds(this);
    }

    /**
     * Return layout with optional custom flags.
     *
     * @return layout directive
     */
    int internalGetLayout()
    {
        if(hasLabel() && !isSizeLocked())
        {
            return super.internalGetLayout() | Item.LAYOUT_NEWLINE_BEFORE;
        }
        else
        {
            return super.internalGetLayout();
        }
    }

}