/*******************************************************************************
 * 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:
 *     Jacob Carlborg <doob@me.com>
 *******************************************************************************/
module dwt.widgets.Dialog;


import dwt.DWT;
import dwt.DWTException;

import dwt.dwthelper.utils;
import dwt.widgets.Display;
import dwt.widgets.Shell;
import dwt.widgets.Widget;

/**
 * This class is the abstract superclass of the classes
 * that represent the built in platform dialogs.
 * A <code>Dialog</code> typically contains other widgets
 * that are not accessible. A <code>Dialog</code> is not
 * a <code>Widget</code>.
 * <p>
 * This class can also be used as the abstract superclass
 * for user-designed dialogs. Such dialogs usually consist
 * of a Shell with child widgets. The basic template for a
 * user-defined dialog typically looks something like this:
 * <pre><code>
 * public class MyDialog extends Dialog {
 *  Object result;
 *      
 *  public MyDialog (Shell parent, int style) {
 *      super (parent, style);
 *  }
 *  public MyDialog (Shell parent) {
 *      this (parent, 0); // your default style bits go here (not the Shell's style bits)
 *  }
 *  public Object open () {
 *      Shell parent = getParent();
 *      Shell shell = new Shell(parent, DWT.DIALOG_TRIM | DWT.APPLICATION_MODAL);
 *      shell.setText(getText());
 *      // Your code goes here (widget creation, set result, etc).
 *      shell.open();
 *      Display display = parent.getDisplay();
 *      while (!shell.isDisposed()) {
 *          if (!display.readAndDispatch()) display.sleep();
 *      }
 *      return result;
 *  }
 * }
 * </pre></code>
 * <p>
 * Note: The <em>modality</em> styles supported by this class
 * are treated as <em>HINT</em>s, because not all are supported
 * by every subclass on every platform. If a modality style is
 * not supported, it is "upgraded" to a more restrictive modality
 * style that is supported.  For example, if <code>PRIMARY_MODAL</code>
 * is not supported by a particular dialog, it would be upgraded to 
 * <code>APPLICATION_MODAL</code>. In addition, as is the case
 * for shells, the window manager for the desktop on which the
 * instance is visible has ultimate control over the appearance
 * and behavior of the instance, including its modality.
 * <dl>
 * <dt><b>Styles:</b></dt>
 * <dd>APPLICATION_MODAL, PRIMARY_MODAL, SYSTEM_MODAL</dd>
 * <dt><b>Events:</b></dt>
 * <dd>(none)</dd>
 * </dl>
 * <p>
 * Note: Only one of the styles APPLICATION_MODAL, PRIMARY_MODAL,
 * and SYSTEM_MODAL may be specified.
 * </p>
 * 
 * @see Shell
 * @see <a href="http://www.eclipse.org/swt/examples.php">DWT Example: ControlExample</a>
 * @see <a href="http://www.eclipse.org/swt/">Sample code and further information</a>
 */

public abstract class Dialog {
    int style;
    Shell parent;
    String title;

/**
 * Constructs a new instance of this class given only its
 * parent.
 *
 * @param parent a shell which will be the parent of the new instance
 *
 * @exception IllegalArgumentException <ul>
 *    <li>ERROR_NULL_ARGUMENT - if the parent is null</li>
 * </ul>
 * @exception DWTException <ul>
 *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the parent</li>
 * </ul>
 */
public this (Shell parent) {
    this (parent, DWT.PRIMARY_MODAL);
}

/**
 * Constructs a new instance of this class given its parent
 * and a style value describing its behavior and appearance.
 * <p>
 * The style value is either one of the style constants defined in
 * class <code>DWT</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>DWT</code> style constants. The class description
 * lists the style constants that are applicable to the class.
 * Style bits are also inherited from superclasses.
 *
 * @param parent a shell which will be the parent of the new instance
 * @param style the style of dialog to construct
 *
 * @exception IllegalArgumentException <ul>
 *    <li>ERROR_NULL_ARGUMENT - if the parent is null</li>
 * </ul>
 * @exception DWTException <ul>
 *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the parent</li>
 * </ul>
 * 
 * @see DWT#PRIMARY_MODAL
 * @see DWT#APPLICATION_MODAL
 * @see DWT#SYSTEM_MODAL
 */
public this (Shell parent, int style) {
    checkParent (parent);
    this.parent = parent;
    this.style = style;
    title = "";
}

/**
 * Checks that this class can be subclassed.
 * <p>
 * IMPORTANT: See the comment in <code>Widget.checkSubclass()</code>.
 * </p>
 *
 * @exception DWTException <ul>
 *    <li>ERROR_INVALID_SUBCLASS - if this class is not an allowed subclass</li>
 * </ul>
 *
 * @see Widget#checkSubclass
 */
protected void checkSubclass () {
    if (!Display.isValidClass (this.classinfo)) {
        error (DWT.ERROR_INVALID_SUBCLASS);
    }
}

/**
 * Throws an exception if the specified widget can not be
 * used as a parent for the receiver.
 *
 * @exception IllegalArgumentException <ul>
 *    <li>ERROR_NULL_ARGUMENT - if the parent is null</li>
 *    <li>ERROR_INVALID_ARGUMENT - if the parent is disposed</li>
 * </ul>
 * @exception DWTException <ul>
 *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the parent</li>
 * </ul>
 */
void checkParent (Shell parent) {
    if (parent is null) error (DWT.ERROR_NULL_ARGUMENT);
    parent.checkWidget ();
}

static int checkStyle (Shell parent, int style) {
    if ((style & (DWT.PRIMARY_MODAL | DWT.APPLICATION_MODAL | DWT.SYSTEM_MODAL)) is 0) {
        style |= DWT.APPLICATION_MODAL;
    }
    style &= ~DWT.MIRRORED;
    if ((style & (DWT.LEFT_TO_RIGHT | DWT.RIGHT_TO_LEFT)) is 0) {
        if (parent !is null) {
            if ((parent.style & DWT.LEFT_TO_RIGHT) !is 0) style |= DWT.LEFT_TO_RIGHT;
            if ((parent.style & DWT.RIGHT_TO_LEFT) !is 0) style |= DWT.RIGHT_TO_LEFT;
        }
    }
    return Widget.checkBits (style, DWT.LEFT_TO_RIGHT, DWT.RIGHT_TO_LEFT, 0, 0, 0, 0);
}

/**
 * Does whatever dialog specific cleanup is required, and then
 * uses the code in <code>DWTError.error</code> to handle the error.
 *
 * @param code the descriptive error code
 *
 * @see DWT#error(int)
 */
void error (int code) {
    DWT.error(code);
}

/**
 * Returns the receiver's parent, which must be a <code>Shell</code>
 * or null.
 *
 * @return the receiver's parent
 *
 * @exception DWTException <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 Shell getParent () {
    return parent;
}

/**
 * Returns the receiver's style information.
 * <p>
 * Note that, the value which is returned by this method <em>may
 * not match</em> the value which was provided to the constructor
 * when the receiver was created. 
 * </p>
 *
 * @return the style bits
 *
 * @exception DWTException <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 int getStyle () {
    return style;
}

/**
 * Returns the receiver's text, which is the string that the
 * window manager will typically display as the receiver's
 * <em>title</em>. If the text has not previously been set, 
 * returns an empty string.
 *
 * @return the text
 *
 * @exception DWTException <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 String getText () {
    return title;
}

/**
 * Sets the receiver's text, which is the string that the
 * window manager will typically display as the receiver's
 * <em>title</em>, to the argument, which must not be null. 
 *
 * @param string the new text
 *
 * @exception IllegalArgumentException <ul>
 *    <li>ERROR_NULL_ARGUMENT - if the text is null</li>
 * </ul>
 * @exception DWTException <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 void setText (String string) {
    //if (string is null) error (DWT.ERROR_NULL_ARGUMENT);
    title = string;
}

}