/*******************************************************************************
 * Copyright (c) 2000, 2008 IBM Corporation and others.
 * 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
 * Port to the D programming language:
 *     Frank Benoit <benoit@tionex.de>
 *******************************************************************************/
module dwt.custom.TreeEditor;

import dwt.dwthelper.utils;


import dwt.DWT;
import dwt.events.ControlEvent;
import dwt.events.ControlListener;
import dwt.events.TreeEvent;
import dwt.events.TreeListener;
import dwt.graphics.Rectangle;
import dwt.widgets.Control;
import dwt.widgets.Display;
import dwt.widgets.Tree;
import dwt.widgets.TreeColumn;
import dwt.widgets.TreeItem;
import dwt.custom.ControlEditor;
import dwt.dwthelper.Runnable;

/**
*
* A TreeEditor is a manager for a Control that appears above a cell in a Tree and tracks with the
* moving and resizing of that cell.  It can be used to display a text widget above a cell
* in a Tree so that the user can edit the contents of that cell.  It can also be used to display
* a button that can launch a dialog for modifying the contents of the associated cell.
*
* <p> Here is an example of using a TreeEditor:
* <code><pre>
*   final Tree tree = new Tree(shell, DWT.BORDER);
*   for (int i = 0; i &lt; 3; i++) {
*       TreeItem item = new TreeItem(tree, DWT.NONE);
*       item.setText("item " + i);
*       for (int j = 0; j &lt; 3; j++) {
*           TreeItem subItem = new TreeItem(item, DWT.NONE);
*           subItem.setText("item " + i + " " + j);
*       }
*   }
*
*   final TreeEditor editor = new TreeEditor(tree);
*   //The editor must have the same size as the cell and must
*   //not be any smaller than 50 pixels.
*   editor.horizontalAlignment = DWT.LEFT;
*   editor.grabHorizontal = true;
*   editor.minimumWidth = 50;
*
*   tree.addSelectionListener(new SelectionAdapter() {
*       public void widgetSelected(SelectionEvent e) {
*           // Clean up any previous editor control
*           Control oldEditor = editor.getEditor();
*           if (oldEditor !is null) oldEditor.dispose();
*
*           // Identify the selected row
*           TreeItem item = (TreeItem)e.item;
*           if (item is null) return;
*
*           // The control that will be the editor must be a child of the Tree
*           Text newEditor = new Text(tree, DWT.NONE);
*           newEditor.setText(item.getText());
*           newEditor.addModifyListener(new ModifyListener() {
*               public void modifyText(ModifyEvent e) {
*                   Text text = (Text)editor.getEditor();
*                   editor.getItem().setText(text.getText());
*               }
*           });
*           newEditor.selectAll();
*           newEditor.setFocus();
*           editor.setEditor(newEditor, item);
*       }
*   });
* </pre></code>
*
* @see <a href="http://www.eclipse.org/swt/snippets/#treeeditor">TreeEditor snippets</a>
* @see <a href="http://www.eclipse.org/swt/">Sample code and further information</a>
*/

public class TreeEditor : ControlEditor {
    Tree tree;
    TreeItem item;
    int column = 0;
    ControlListener columnListener;
    TreeListener treeListener;
    Runnable timer;
    static const int TIMEOUT = 1500;

/**
* Creates a TreeEditor for the specified Tree.
*
* @param tree the Tree Control above which this editor will be displayed
*
*/
public this (Tree tree) {
    super(tree);
    this.tree = tree;

    columnListener = new class() ControlListener {
        public void controlMoved(ControlEvent e){
            layout();
        }
        public void controlResized(ControlEvent e){
            layout();
        }
    };
    timer = new class() Runnable {
        public void run() {
            layout ();
        }
    };
    treeListener = new class() TreeListener {
        Runnable runnable;
        this(){
            runnable = new class() Runnable {
                public void run() {
                    if (this.outer.outer.editor is null || this.outer.outer.editor.isDisposed()) return;
                    if (this.outer.outer.tree.isDisposed()) return;
                    layout();
                    this.outer.outer.editor.setVisible(true);
                }
            };
        }
        public void treeCollapsed(TreeEvent e) {
            if (this.outer.editor is null || this.outer.editor.isDisposed ()) return;
            this.outer.editor.setVisible(false);
            e.display.asyncExec(runnable);
        }
        public void treeExpanded(TreeEvent e) {
            if (this.outer.editor is null || this.outer.editor.isDisposed ()) return;
            this.outer.editor.setVisible(false);
            e.display.asyncExec(runnable);
        }
    };
    tree.addTreeListener(treeListener);

    // To be consistent with older versions of DWT, grabVertical defaults to true
    grabVertical = true;
}

override Rectangle computeBounds () {
    if (item is null || column is -1 || item.isDisposed()) return new Rectangle(0, 0, 0, 0);
    Rectangle cell = item.getBounds(column);
    Rectangle rect = item.getImageBounds(column);
    cell.x = rect.x + rect.width;
    cell.width -= rect.width;
    Rectangle area = tree.getClientArea();
    if (cell.x < area.x + area.width) {
        if (cell.x + cell.width > area.x + area.width) {
            cell.width = area.x + area.width - cell.x;
        }
    }
    Rectangle editorRect = new Rectangle(cell.x, cell.y, minimumWidth, minimumHeight);

    if (grabHorizontal) {
        if (tree.getColumnCount() is 0) {
            // Bounds of tree item only include the text area - stretch out to include
            // entire client area
            cell.width = area.x + area.width - cell.x;
        }
        editorRect.width = Math.max(cell.width, minimumWidth);
    }

    if (grabVertical) {
        editorRect.height = Math.max(cell.height, minimumHeight);
    }

    if (horizontalAlignment is DWT.RIGHT) {
        editorRect.x += cell.width - editorRect.width;
    } else if (horizontalAlignment is DWT.LEFT) {
        // do nothing - cell.x is the right answer
    } else { // default is CENTER
        editorRect.x += (cell.width - editorRect.width)/2;
    }
    // don't let the editor overlap with the + / - of the tree
    editorRect.x = Math.max(cell.x, editorRect.x);

    if (verticalAlignment is DWT.BOTTOM) {
        editorRect.y += cell.height - editorRect.height;
    } else if (verticalAlignment is DWT.TOP) {
        // do nothing - cell.y is the right answer
    } else { // default is CENTER
        editorRect.y += (cell.height - editorRect.height)/2;
    }
    return editorRect;
}

/**
 * Removes all associations between the TreeEditor and the row in the tree.  The
 * tree and the editor Control are <b>not</b> disposed.
 */
public override void dispose () {
    if (tree !is null && !tree.isDisposed()) {
        if (this.column > -1 && this.column < tree.getColumnCount()){
            TreeColumn treeColumn = tree.getColumn(this.column);
            treeColumn.removeControlListener(columnListener);
        }
        if (treeListener !is null) tree.removeTreeListener(treeListener);
    }
    columnListener = null;
    treeListener = null;
    tree = null;
    item = null;
    column = 0;
    timer = null;
    super.dispose();
}

/**
* Returns the zero based index of the column of the cell being tracked by this editor.
*
* @return the zero based index of the column of the cell being tracked by this editor
*
* @since 3.1
*/
public int getColumn () {
    return column;
}

/**
* Returns the TreeItem for the row of the cell being tracked by this editor.
*
* @return the TreeItem for the row of the cell being tracked by this editor
*/
public TreeItem getItem () {
    return item;
}

void resize () {
    layout();
    /*
     * On some platforms, the table scrolls when an item that
     * is partially visible at the bottom of the table is
     * selected.  Ensure that the correct row is edited by
     * laying out one more time in a timerExec().
     */
    if (tree !is null) {
        Display display = tree.getDisplay();
        display.timerExec(-1, timer);
        display.timerExec(TIMEOUT, timer);
    }
}

/**
* Sets the zero based index of the column of the cell being tracked by this editor.
*
* @param column the zero based index of the column of the cell being tracked by this editor
*
* @since 3.1
*/
public void setColumn(int column) {
    int columnCount = tree.getColumnCount();
    // Separately handle the case where the tree has no TreeColumns.
    // In this situation, there is a single default column.
    if (columnCount is 0) {
        this.column = (column is 0) ? 0 : -1;
        resize();
        return;
    }
    if (this.column > -1 && this.column < columnCount){
        TreeColumn treeColumn = tree.getColumn(this.column);
        treeColumn.removeControlListener(columnListener);
        this.column = -1;
    }

    if (column < 0  || column >= tree.getColumnCount()) return;

    this.column = column;
    TreeColumn treeColumn = tree.getColumn(this.column);
    treeColumn.addControlListener(columnListener);
    resize();
}

/**
* Specifies the <code>TreeItem</code> that is to be edited.
*
* @param item the item to be edited
*/
public void setItem (TreeItem item) {
    this.item = item;
    resize();
}

/**
* Specify the Control that is to be displayed and the cell in the tree that it is to be positioned above.
*
* <p>Note: The Control provided as the editor <b>must</b> be created with its parent being the Tree control
* specified in the TreeEditor constructor.
*
* @param editor the Control that is displayed above the cell being edited
* @param item the TreeItem for the row of the cell being tracked by this editor
* @param column the zero based index of the column of the cell being tracked by this editor
*
* @since 3.1
*/
public void setEditor (Control editor, TreeItem item, int column) {
    setItem(item);
    setColumn(column);
    setEditor(editor);
}
public override void setEditor (Control editor) {
    super.setEditor(editor);
    resize();
}

/**
* Specify the Control that is to be displayed and the cell in the tree that it is to be positioned above.
*
* <p>Note: The Control provided as the editor <b>must</b> be created with its parent being the Tree control
* specified in the TreeEditor constructor.
*
* @param editor the Control that is displayed above the cell being edited
* @param item the TreeItem for the row of the cell being tracked by this editor
*/
public void setEditor (Control editor, TreeItem item) {
    setItem(item);
    setEditor(editor);
}

public override void layout () {
    if (tree is null || tree.isDisposed()) return;
    if (item is null || item.isDisposed()) return;
    int columnCount = tree.getColumnCount();
    if (columnCount is 0 && column !is 0) return;
    if (columnCount > 0 && (column < 0 || column >= columnCount)) return;
    super.layout();
}

}