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

 * Copyright (c) 2000, 2007 IBM Corporation and others.

 * Portion Copyright (c) 2008 Nokia Corporation and/or its subsidiary(-ies).

 * All rights reserved. This program and the accompanying materials

 * are made available under the terms of the Eclipse Public License v1.0

 * which accompanies this distribution, and is available at

 * http://www.eclipse.org/legal/epl-v10.html

 *

 * Contributors:

 *     IBM Corporation - initial API and implementation

 *     Nokia Corporation - Qt implementation

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

package org.eclipse.swt.widgets;

import org.eclipse.swt.SWT;

import org.eclipse.swt.SWTException;

import org.eclipse.swt.graphics.Color;

import org.eclipse.swt.graphics.Font;

import org.eclipse.swt.graphics.Image;

import org.eclipse.swt.graphics.Internal_GfxPackageSupport;

import org.eclipse.swt.graphics.Rectangle;

import org.eclipse.swt.internal.qt.OS;

/**

 * Instances of this class represent a selectable user interface object that

 * represents a hierarchy of tree items in a tree widget.

 * 

 * <dl>

 * <dt><b>Styles:</b></dt>

 * <dd>(none)</dd>

 * <dt><b>Events:</b></dt>

 * <dd>(none)</dd>

 * </dl>

 * <p>

 * IMPORTANT: This class is <em>not</em> intended to be subclassed.

 * </p>

 */

public class TreeItem extends Item {

    static Tree checkNull(Tree control) {

        if (control == null)

            SWT.error(SWT.ERROR_NULL_ARGUMENT);

        return control;

    }

    static TreeItem checkNull(TreeItem item) {

        if (item == null)

            SWT.error(SWT.ERROR_NULL_ARGUMENT);

        return item;

    }

    Tree tree;

    int itemHandle;

    TreeItem parentItem;

    TreeItem[] childrenItems;

    int childrenItemCount;

    int[] childrenItemsHandle;

    Font font;

    Color background;

    Color foreground;

    boolean grayed;

    // Tells if the item has all the data fetched (can be false only in 

    // SWT.VIRTUAL style Tree)

    boolean cached;

    int checkedState;

    boolean selection;

    /**

     * Constructs a new instance of this class given its parent (which must be a

     * <code>Tree</code> or a <code>TreeItem</code>) and a style value

     * describing its behavior and appearance. The item is added to the end of

     * the items maintained by its parent.

     * <p>

     * The style value is either one of the style constants defined in class

     * <code>SWT</code> which is applicable to instances of this class, or must

     * be built by <em>bitwise OR</em>'ing together (that is, using the

     * <code>int</code> "|" operator) two or more of those <code>SWT</code>

     * style constants. The class description lists the style constants that are

     * applicable to the class. Style bits are also inherited from superclasses.

     * </p>

     * 

     * @param parent

     *            a tree control which will be the parent of the new instance

     *            (cannot be null)

     * @param style

     *            the style of control to construct

     * 

     * @exception IllegalArgumentException

     *                <ul>

     *                <li>ERROR_NULL_ARGUMENT - if the parent is null</li>

     *                </ul>

     * @exception SWTException

     *                <ul>

     *                <li>ERROR_THREAD_INVALID_ACCESS - if not called from the

     *                thread that created the parent</li>

     *                <li>ERROR_INVALID_SUBCLASS - if this class is not an

     *                allowed subclass</li>

     *                </ul>

     * 

     * @see SWT

     * @see Widget#checkSubclass

     * @see Widget#getStyle

     */

    public TreeItem(Tree parent, int style) {

        this(parent, style, checkNull(parent).getItemCount(), true);

    }

    /**

     * Constructs a new instance of this class given its parent (which must be a

     * <code>Tree</code> or a <code>TreeItem</code>), a style value describing

     * its behavior and appearance, and the index at which to place it in the

     * items maintained by its parent.

     * <p>

     * The style value is either one of the style constants defined in class

     * <code>SWT</code> which is applicable to instances of this class, or must

     * be built by <em>bitwise OR</em>'ing together (that is, using the

     * <code>int</code> "|" operator) two or more of those <code>SWT</code>

     * style constants. The class description lists the style constants that are

     * applicable to the class. Style bits are also inherited from superclasses.

     * </p>

     * 

     * @param parent

     *            a tree control which will be the parent of the new instance

     *            (cannot be null)

     * @param style

     *            the style of control to construct

     * @param index

     *            the index to store the receiver in its parent

     * 

     * @exception IllegalArgumentException

     *                <ul>

     *                <li>ERROR_NULL_ARGUMENT - if the parent is null</li>

     *                </ul>

     * @exception SWTException

     *                <ul>

     *                <li>ERROR_THREAD_INVALID_ACCESS - if not called from the

     *                thread that created the parent</li>

     *                <li>ERROR_INVALID_SUBCLASS - if this class is not an

     *                allowed subclass</li>

     *                </ul>

     * 

     * @see SWT

     * @see Widget#checkSubclass

     * @see Widget#getStyle

     */

    public TreeItem(Tree parent, int style, int index) {

        this(parent, style, index, true);

    }

    TreeItem(Tree parent, int style, int index, boolean create) {

        super(parent, style);

        this.tree = parent;

        if( create ){

            itemHandle = OS.QTreeWidgetItem_new();

            OS.QTreeWidget_insertTopLevelItem(parent.topHandle,

                    itemHandle, index);

            parent.addTopLevelItem(this, index, itemHandle);

            ensureValid( index );

        }

    }

    /**

     * Constructs a new instance of this class given its parent (which must be a

     * <code>Tree</code> or a <code>TreeItem</code>) and a style value

     * describing its behavior and appearance. The item is added to the end of

     * the items maintained by its parent.

     * <p>

     * The style value is either one of the style constants defined in class

     * <code>SWT</code> which is applicable to instances of this class, or must

     * be built by <em>bitwise OR</em>'ing together (that is, using the

     * <code>int</code> "|" operator) two or more of those <code>SWT</code>

     * style constants. The class description lists the style constants that are

     * applicable to the class. Style bits are also inherited from superclasses.

     * </p>

     * 

     * @param parentItem

     *            a tree control which will be the parent of the new instance

     *            (cannot be null)

     * @param style

     *            the style of control to construct

     * 

     * @exception IllegalArgumentException

     *                <ul>

     *                <li>ERROR_NULL_ARGUMENT - if the parent is null</li>

     *                </ul>

     * @exception SWTException

     *                <ul>

     *                <li>ERROR_THREAD_INVALID_ACCESS - if not called from the

     *                thread that created the parent</li>

     *                <li>ERROR_INVALID_SUBCLASS - if this class is not an

     *                allowed subclass</li>

     *                </ul>

     * 

     * @see SWT

     * @see Widget#checkSubclass

     * @see Widget#getStyle

     */

    public TreeItem(TreeItem parent, int style) {

        this(parent, style, checkNull(parent).getItemCount(), true);

    }

    /**

     * Constructs a new instance of this class given its parent (which must be a

     * <code>Tree</code> or a <code>TreeItem</code>), a style value describing

     * its behavior and appearance, and the index at which to place it in the

     * items maintained by its parent.

     * <p>

     * The style value is either one of the style constants defined in class

     * <code>SWT</code> which is applicable to instances of this class, or must

     * be built by <em>bitwise OR</em>'ing together (that is, using the

     * <code>int</code> "|" operator) two or more of those <code>SWT</code>

     * style constants. The class description lists the style constants that are

     * applicable to the class. Style bits are also inherited from superclasses.

     * </p>

     * 

     * @param parentItem

     *            a tree control which will be the parent of the new instance

     *            (cannot be null)

     * @param style

     *            the style of control to construct

     * @param index

     *            the index to store the receiver in its parent

     * 

     * @exception IllegalArgumentException

     *                <ul>

     *                <li>ERROR_NULL_ARGUMENT - if the parent is null</li>

     *                </ul>

     * @exception SWTException

     *                <ul>

     *                <li>ERROR_THREAD_INVALID_ACCESS - if not called from the

     *                thread that created the parent</li>

     *                <li>ERROR_INVALID_SUBCLASS - if this class is not an

     *                allowed subclass</li>

     *                </ul>

     * 

     * @see SWT

     * @see Widget#checkSubclass

     * @see Widget#getStyle

     */

    public TreeItem(TreeItem parent, int style, int index) {

        this(parent, style, index, true);

    }

    TreeItem(TreeItem parent, int style, int index, boolean create) {

        super(parent, style);

        this.parentItem = parent;

        this.tree = parentItem.tree;

        if( create ){

            itemHandle = OS.QTreeWidgetItem_new();

            OS.QTreeWidgetItem_insertChild(parent.internal_itemHandle(),

                    itemHandle, index);

            parentItem.addChild(this, index, itemHandle);

            ensureValid( index );

        }

    }

    TreeItem _getItem (int index) {

        if ((tree.getStyle() & SWT.VIRTUAL) == 0) return childrenItems [index];

        if (childrenItems [index] != null) return childrenItems [index];

        return childrenItems [index] = new TreeItem (this, SWT.NONE, index, false);

    }

    int _getItemHandle(){

        int newItemHandle = 0;

        TreeItem parentItem = getParentItem();

        if(parentItem!=null) {

            for(int i=0;i<parentItem.childrenItemCount;i++){

                if(this==parentItem.childrenItems[i]){ 

                    newItemHandle = parentItem.childrenItemsHandle[i];

                    break;

                }

            }

        } else {

            for(int i=0;i<tree.topLevelItemCount;i++){

                if(this==tree.topLevelItems[i]){ 

                    newItemHandle = tree.topLevelItemsHandle[i];

                    break;

                }

            }

        }

        return newItemHandle;

    }

    /* Add a new child to the TreeItem's list of children. Add the item at the

     * given index. An index of -1 implies that the child should be added to the

     * end of the TreeItem's list of children.

     */

    void addChild(TreeItem item, int index, int itemHandle) {

        increaseChildrenArraySize();

        if (!(0 <= index && index <= childrenItemCount)) 

            error (SWT.ERROR_INVALID_RANGE);

        // Put the new item in the correct place in item array

        System.arraycopy (childrenItems, index, childrenItems, 

                index + 1, childrenItemCount+1 - index);

        childrenItems[index] = item;

        //itemCount is already increase in the previous line.

        System.arraycopy (childrenItemsHandle, index, childrenItemsHandle,

                index + 1, childrenItemCount+1 - index);

        childrenItemsHandle[index] = itemHandle;

        childrenItemCount++;

    }

    protected void checkSubclass() {

        if (!isValidSubclass())

            error(SWT.ERROR_INVALID_SUBCLASS);

    }

    void clearSelection() {

        for (int i = 0; i < childrenItemCount; ++i) {

            TreeItem child = _getItem(i);

            child.selection=false;

            child.clearSelection();

        }

    }

    /*

     * Ensures that the TreeItem has all the native and Java side

     * resources created.

     * @param index Index of the item in Tree

     */

    void ensureValid(int index) {

        if (cached) {

            return;

        }

        cached = true;

        if(internal_itemHandle() == 0) {

            if(parentItem == null){

                itemHandle = tree.topLevelItemsHandle[index];

            } else {

                itemHandle = parentItem.childrenItemsHandle[index];

            }

        }

        if ((tree.getStyle() & SWT.CHECK) != 0) {

            OS.QTreeWidgetItem_setFlags(itemHandle, OS.QT_ITEMISENABLED

                    | OS.QT_ITEMISUSERCHECKABLE | OS.QT_ITEMISSELECTABLE);

            OS.QTreeWidgetItem_setCheckState(itemHandle, checkedState);

        } else {

            OS.QTreeWidgetItem_setFlags(itemHandle, OS.QT_ITEMISENABLED

                    | OS.QT_ITEMISSELECTABLE);

        }

        // If the user has set background, foreground or font for the whole item

        // set that here for the new column also            

        if (background != null) OS.QTreeWidgetItem_swt_setBackground(itemHandle, background.getRed(), background.getGreen(), background.getBlue(), false);

        if (foreground != null) OS.QTreeWidgetItem_swt_setForeground(itemHandle, foreground.getRed(), foreground.getGreen(), foreground.getBlue(), false);

        if (font != null) OS.QTreeWidgetItem_swt_setFont(itemHandle, font.handle);

        if (text != null) OS.QTreeWidgetItem_setText(itemHandle, text);

        if (image != null) OS.QTreeWidgetItem_setIcon(itemHandle, Internal_GfxPackageSupport.getIconHandle(image));

        tree.ignoreSelectionEvent = true;

        // this code will be executed when we call setSelection(TreeItem[]) in multi style. 

        // if the number of items going to select are 1 and style is single also works

        if(selection && ((tree.getStyle() & SWT.VIRTUAL) != 0)) {

            OS.QTreeWidgetItem_setSelected(internal_itemHandle(), selection);

            // we need to set the selection to false. bcz there is also possible

            //to deselect the item with mouse

            selection = false;

        }

        tree.ignoreSelectionEvent = false;

        tree.updateColumnWidth();

    }

    TreeItem findItem(int itemHandle) {

        TreeItem item = null;

        for (int i = 0; i < childrenItemCount; i++) {

            if (childrenItemsHandle[i] == itemHandle) {

                item = _getItem(i);

                break;

            } else {

                TreeItem childItem = _getItem(i);

                if(childItem.cached){

                    if(childItem.getExpanded())

                        item = childItem.findItem(itemHandle);

                }

                if (item != null)

                    break;

            }

        }

        return item;

    }

    /**

     * Returns the receiver's background color.

     * 

     * @return the background color

     * 

     * @exception SWTException

     *                <ul>

     *                <li>ERROR_WIDGET_DISPOSED - if the receiver has been

     *                disposed</li>

     *                <li>ERROR_THREAD_INVALID_ACCESS - if not called from the

     *                thread that created the receiver</li>

     *                </ul>

     * 

     * @since 2.0

     * 

     */

    public Color getBackground() {

        checkWidget();

        if(cached) {

            if (!tree.checkData(this, getParentItem()))

                error(SWT.ERROR_WIDGET_DISPOSED);

        }

        if (background != null)

            return Internal_GfxPackageSupport.newColor(display, background.handle);

        return tree.getBackground();

    }

    /**

     * Returns a rectangle describing the receiver's size and location relative

     * to its parent.

     * 

     * @return the receiver's bounding rectangle

     * 

     * @exception SWTException

     *                <ul>

     *                <li>ERROR_WIDGET_DISPOSED - if the receiver has been

     *                disposed</li>

     *                <li>ERROR_THREAD_INVALID_ACCESS - if not called from the

     *                thread that created the receiver</li>

     *                </ul>

     */

    public Rectangle getBounds() {

        checkWidget();

        if(cached){

            if (!tree.checkData(this, getParentItem()))

                error(SWT.ERROR_WIDGET_DISPOSED);

            return OS.QTreeWidget_visualItemRect(tree.topHandle,

                    internal_itemHandle());

        } else {

            return OS.QTreeWidget_visualItemRect(tree.topHandle, _getItemHandle());

        }

    }

    /**

     * Returns <code>true</code> if the receiver is checked, and false

     * otherwise. When the parent does not have the

     * <code>CHECK style, return false.

     * <p>

     * 

     * @return the checked state

     * 

     * @exception SWTException

     *                <ul> <li>ERROR_WIDGET_DISPOSED - if the receiver has been

     *                disposed</li> <li>ERROR_THREAD_INVALID_ACCESS - if not

     *                called from the thread that created the receiver</li>

     *                </ul>

     */

    public boolean getChecked() {

        checkWidget();

        if(cached){

            if (!tree.checkData(this, getParentItem()))

                error(SWT.ERROR_WIDGET_DISPOSED);

            if ((tree.style & SWT.CHECK) == 0)

                return false;

            return OS.QTreeWidgetItem_checkState(internal_itemHandle()) == OS.QT_CHECKED;

        } else {

            if(checkedState == OS.QT_CHECKED) {

                return true;

            } else {

                return false;

            }

        }

    }

    /**

     * Gets the index of an item.

     * <p>

     * -1 is returned if the item is not found from children.

     * 

     * @param time

     *            the search item

     * @return the index of the item

     * 

     * @exception IllegalArgumentException

     *                <ul>

     *                <li>ERROR_NULL_ARGUMENT - if the item is null</li>

     *                </ul>

     * @exception SWTException

     *                <ul>

     *                <li>ERROR_WIDGET_DISPOSED - if the receiver has been

     *                disposed</li> <li>ERROR_THREAD_INVALID_ACCESS - if not

     *                called from the thread that created the receiver</li>

     *                </ul>

     */

    int getChildItemIndex(TreeItem item) {

        if (item == null)

            error(SWT.ERROR_NULL_ARGUMENT);

        if (childrenItemCount == 0 || childrenItems == null

                || item.getParent() != tree)

            return -1;

        return OS.QTreeWidgetItem_indexOfChild(internal_itemHandle(), item.internal_itemHandle());

    }

    /**

     * Returns <code>true</code> if the receiver is expanded, and false

     * otherwise.

     * <p>

     * 

     * @return the expanded state

     * 

     * @exception SWTException

     *                <ul>

     *                <li>ERROR_WIDGET_DISPOSED - if the receiver has been

     *                disposed</li> <li>ERROR_THREAD_INVALID_ACCESS - if not

     *                called from the thread that created the receiver</li>

     *                </ul>

     */

    public boolean getExpanded() {

        checkWidget();

        if(cached){