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

 * Copyright (c) 2004, 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:

 *     Yu You (Nokia Corp.)- initial API specification

 *     Nokia Corporation - S60 implementation

 *     Nokia Corporation - QT implementation

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

package org.eclipse.ercp.swt.mobile;

import org.eclipse.swt.*;

import org.eclipse.swt.events.MouseEvent;

import org.eclipse.swt.events.MouseListener;

import org.eclipse.swt.graphics.*;

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

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

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

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

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

import org.eclipse.swt.widgets.*;

import java.lang.Math;

/**

 *

 * A CaptionedControl is used to display a label (caption) in front of a

 * control. An optional trailing text can be used after the control, for

 * example, to indicate units of measurement.

 * <p>

 * The highlighting is implementation dependent. Typically, a focused

 * CaptionedControl will highlight all its elements, i.e. the leading label, the

 * control, and optional trailing label, when it gets focus. The positioning

 * order for the captions is determined by the <code>SWT.LEFT_TO_RIGHT</code>

 * and <code>SWT.RIGHT_TO_LEFT</code> styles hints.

 * </p>

 *

 * <p>

 * CaptionedControl does not support nested CaptionedControls. An exception will

 * be thrown when an instance of CaptionedControl is given as the constructor's

 * argument. To change the control contained by the CaptionedControl, a new

 * control can be created using the CaptionedControl as its parent control. The

 * old control must be disposed by the application manually. Only one control

 * can be active and visible in a CaptionedControl. Which control is displayed

 * when multiple controls have been added is implementation-dependent.

 * </p>

 * <p>

 * <em>Example code:</em>

 * </p>

 * <p>

 * <code><pre>

 * CaptionedControl control = new CaptionedControl(shell, SWT.NONE);

 * ConstraintedText currency = new ConstraintedText(control, SWT.NONE,

 *      ConstraintedText.NUMERIC);

 * control.setText("Velocity");

 * control.getTrailingText("cm");

 * </pre></code>

 * </p>

 *

 * <p>

 * <dl>

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

 * <dd>SWT.LEFT_TO_RIGHT (default)</dd>

 * <dd>SWT.RIGHT_TO_LEFT</dd>

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

 * <dd>(none)</dd>

 * </dl>

 * <p>

 * Note: Even this class is a subclass of Composite, it does not make sense to

 * set a layout on it.

 * </p>

 * <p>

 * IMPORTANT: This class is not intended to be subclassed.

 * </p>

 *

 */

public final class CaptionedControl extends Composite {

    boolean initPhase;

    private int focusSignalProxy;

    private MouseListener mouseListener;

    private boolean monitorMouseEvent;

static final class CaptionedControlPackageProxy extends PackageProxy {

    public void createHandle(int index) {

        ((CaptionedControl)w).createHandle(index);

    }

    public void addControl(Control control) {

        ((CaptionedControl)w).addControl(control);

    }

    public void qt_signal_qapplication_focusChanged(int old, int now) {

        ((CaptionedControl)w).qt_signal_qapplication_focusChanged(old, now);

    }

    public void removeControl(Control control) {

        ((CaptionedControl)w).removeControl(control);

    }

}

class CaptionedControlLayout extends Layout {

int checkHint(int hint, int spacing) {

    // Adjust a hint by spacing, check that result is not negative

    if (hint == SWT.DEFAULT) {

        return hint;

    }

    hint -= spacing;

    if (hint < 0) {

        hint = 0;

    }

    return hint;

}

protected Point computeSize(Composite composite, int hint, int hint2, boolean flushCache) {

    Point res = new Point(0, 0);

    int wHint = checkHint(hint, 2 * margin);

    int hHint = checkHint(hint2, 2 * margin);

    CaptionedControlLayoutData data = getData(wHint, hHint);

    if ((getStyle() & SWT.HORIZONTAL) != 0) {

        if (hint == SWT.DEFAULT) {

            res.x = data.row1.x;

        }

        else {

            res.x = data.row1.x - data.child.x + hint;

        }

        if (hint2 == SWT.DEFAULT) {

            res.y = data.row1.y;

        }

        else {

            res.y = hint2;

        }

    }

    else {

        if (hint == SWT.DEFAULT) {

            res.x = Math.max(data.row1.x, data.row2.x);

        }

        else {

            res.x = data.trail.x + Math.max( data.row1.x, hint);

        }

        if (hint2 == SWT.DEFAULT) {

            res.y = data.row1.y + data.row2.y;

        }

        else {

            res.y = data.row1.y + Math.max(hint2, data.trail.y);

        }

    }

    // Since the margins are big enough, adding the border is pointless.

    res.x += 2 * margin;

    res.y += 2 * margin;

    return res;

}

protected void layout(Composite composite, boolean flushCache) {

    Point size = composite.getSize();

    if (size.x <= 0 || size.y <= 0) {

        return;

    }

    CaptionedControlLayoutData data = getData(size.x, size.y);

    int x = margin;

    int y = margin;

    int w = size.x - 2 * margin;

    int h = 0;

    if ((getStyle() & SWT.HORIZONTAL) != 0) {

        h = size.y - 2 * margin;

    }

    else {

        h = data.row1.y;

    }

    if (h < 0) h = 0;

    imageLabel.setBounds(x, y, data.img.x, h);

    x += data.img.x;

    titleLabel.setBounds(x, y, data.title.x, h);

    x += data.title.x;

    int trailW = data.trail.x;

    if ((getStyle() & SWT.VERTICAL) != 0) {

        y += h;

        h = size.y - data.row1.y - 2 * margin;

        if (h < 0) h = 0;

        x = margin;

        if (child == null) {

            trailW = data.row1.x - 2 * margin;

        }

    }

    int childW = 0;

    if (child != null) {

        if ((getStyle() & SWT.HORIZONTAL) != 0) {

            childW = w - data.img.x - data.title.x - data.trail.x;

        }

        else {

            childW = w - data.trail.x;

        }

        if (childW < 0) {

            childW = 0;

        }

        child.setBounds(x, y, childW, h);

        x += childW;

    }

    trailLabel.setBounds(x, y, trailW, h);

}

protected CaptionedControlLayoutData getData() {

    return getData(SWT.DEFAULT, SWT.DEFAULT);

}

protected CaptionedControlLayoutData getData(int wHint, int hHint) {

    CaptionedControlLayoutData res = new CaptionedControlLayoutData();

    int extra = spacing * 2;

    wHint = checkHint(wHint, extra);

    hHint = checkHint(hHint, extra);

    if ((getStyle() & SWT.HORIZONTAL) != 0) {

        if (imageLabel.getImage() != null) {

            res.img = imageLabel.computeSize(SWT.DEFAULT, SWT.DEFAULT);

        }

        String caption = titleLabel.getText();

        if (caption != null && caption.length() > 0) {

            res.title = titleLabel.computeSize(SWT.DEFAULT, SWT.DEFAULT);

        }

        String trail = trailLabel.getText();

        if (trail != null && trail.length() > 0) {

            res.trail = trailLabel.computeSize(SWT.DEFAULT, SWT.DEFAULT);

        }

    } else {

        if (imageLabel.getImage() != null) {

            res.img = imageLabel.computeSize(SWT.DEFAULT, SWT.DEFAULT);

        }

        String caption = titleLabel.getText();

        if (caption != null && caption.length() > 0) {

            if (wHint != SWT.DEFAULT) {

                int hint = wHint - res.img.x;

                if (hint < 0) {

                    hint = 0;

                }

                res.title = titleLabel.computeSize(hint, SWT.DEFAULT);

            } else {

                res.title = titleLabel.computeSize(SWT.DEFAULT, SWT.DEFAULT);

            }

        }

        String trail = trailLabel.getText();

        if (trail != null && trail.length() > 0) {

            res.trail = trailLabel.computeSize(SWT.DEFAULT, SWT.DEFAULT);

        }

    }

    if (res.img.x > 0 && res.img.y > 0) {

        res.img.x += extra;

        res.img.y += extra;

    }

    if (res.title.x > 0 && res.title.y > 0) {

        res.title.x += extra;

        res.title.y += extra;

    }

    if (res.trail.x > 0 && res.trail.y > 0) {

        res.trail.x += extra;

        res.trail.y += extra;

    }

    if ((getStyle() & SWT.HORIZONTAL) != 0) {

        if (child != null) {

            res.child = child.computeSize(SWT.DEFAULT, SWT.DEFAULT);

            if (wHint != SWT.DEFAULT) {

                res.child.x = wHint - res.img.x - res.title.x - res.trail.x;

                if (res.child.x < 0) {

                    res.child.x = 0;

                }

            }

        }

    } else {

        if (child != null) {

            if (wHint != SWT.DEFAULT) {

                res.child = child.computeSize(wHint-res.trail.x, SWT.DEFAULT);

            } else {

                res.child = child.computeSize(SWT.DEFAULT, SWT.DEFAULT);

            }

            if (hHint != SWT.DEFAULT) {

                res.child.y = hHint - res.row1.y;

            }

        }

    }

    if ((getStyle() & SWT.HORIZONTAL) != 0) {

        res.row1.x = res.img.x + res.title.x + res.child.x + res.trail.x;

        res.row1.y = Math.max(res.row1.y, res.img.y);

        res.row1.y = Math.max(res.row1.y, res.title.y);

        res.row1.y = Math.max(res.row1.y, res.trail.y);

        res.row1.y = Math.max(res.row1.y, res.child.y);

    }

    else {

        // If the first row would expand to be bigger than the contained

        // control, adjust title caption width.

        if ((child != null) && (res.img.x + res.title.x > res.child.x + res.trail.x)) {

            int width = res.child.x + res.trail.x - res.img.x;

            if (width < 0) {

                width = 0;

            }

            Point newTitle = titleLabel.computeSize(width, SWT.DEFAULT);

            // Adjust title size only if the adjustment causes line count to

            // change (i.e. title height increases)

            if (newTitle.y > res.title.y) {

                res.title = newTitle;

            }

        }

        res.row1.x = res.img.x + res.title.x;

        res.row1.y = Math.max(res.row1.y, res.img.y);

        res.row1.y = Math.max(res.row1.y, res.title.y);

        res.row2.x = res.child.x + res.trail.x;

        res.row2.y = Math.max(res.row2.y, res.trail.y);

        res.row2.y = Math.max(res.row2.y, res.child.y);

    }

    return res;

}

}

class CaptionedControlLayoutData {

    Point img = new Point(0, 0);

    Point title = new Point(0, 0);

    Point trail = new Point(0, 0);

    Point child = new Point(0, 0);

    Point row1 = new Point(0, 0);

    Point row2 = new Point(0, 0);

}

private Label imageLabel;

private Label titleLabel;

private Label trailLabel;

private Control child;

private final int margin = 5;

private final int spacing = 1;

private CaptionedControlLayout layout;

/**

 * 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>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 widget which will be the parent of the new instance (cannot

 *            be null)

 * @param style

 *            the style of widget 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#LEFT_TO_RIGHT

 * @see SWT#RIGHT_TO_LEFT

 */

public CaptionedControl (Composite parent, int style) {

            new CaptionedControlPackageProxy(), false);

    if (parent instanceof CaptionedControl) {

        SWT.error(SWT.ERROR_INVALID_PARENT);

    }

    Internal_PackageSupport.setScrollAreaHandle(this, 0);

    initPhase = true;

    imageLabel = new Label(this, SWT.CENTER);

    if ((style & SWT.VERTICAL) != 0) {

        titleLabel = new Label(this, SWT.LEFT | SWT.WRAP);

    } else {

        titleLabel = new Label(this, SWT.CENTER);

    }

    trailLabel = new Label(this, SWT.CENTER);

    initPhase = false;

    layout = new CaptionedControlLayout();

    super.setLayout(layout);

    layout();

}

void addControl(Control control) {

    if (initPhase) {

        return;

    }

    int policy = OS.QWidget_focusPolicy(Internal_PackageSupport

            .handle(titleLabel));

    if (control instanceof Composite) {

        // let labels to have click focus when contained control is a

        // Composite

        if ((policy & OS.QT_FOCUSPOLICY_CLICKFOCUS) == 0) {

            policy |= OS.QT_FOCUSPOLICY_CLICKFOCUS;

            OS.QWidget_setFocusPolicy(Internal_PackageSupport

                    .handle(imageLabel), policy);

            OS.QWidget_setFocusPolicy(Internal_PackageSupport

                    .topHandle(titleLabel), policy);

            OS.QWidget_setFocusPolicy(Internal_PackageSupport

                    .topHandle(trailLabel), policy);

        }

        // forward focus to focused control if there is

        // otherwise, clean up focus proxy

        Control focusedControl = focusedDescendant(control);

        if (focusedControl != null) {

            OS.QWidget_setFocusProxy(Internal_PackageSupport

                    .topHandle(imageLabel), Internal_PackageSupport

                    .topHandle(focusedControl));

            OS.QWidget_setFocusProxy(Internal_PackageSupport

                    .topHandle(titleLabel), Internal_PackageSupport

                    .topHandle(focusedControl));

            OS.QWidget_setFocusProxy(Internal_PackageSupport

                    .topHandle(trailLabel), Internal_PackageSupport

                    .topHandle(focusedControl));

        } else {

            OS.QWidget_setFocusProxy(Internal_PackageSupport

                    .topHandle(imageLabel), Internal_PackageSupport

                    .topHandle(control));

            OS.QWidget_setFocusProxy(Internal_PackageSupport

                    .topHandle(titleLabel), Internal_PackageSupport

                    .topHandle(control));

            OS.QWidget_setFocusProxy(Internal_PackageSupport

                    .topHandle(trailLabel), Internal_PackageSupport

                    .topHandle(control));

        }

        if (focusSignalProxy == 0) {

            // starting to monitor focus change if it has not be started yet

            // from now on, focus changed event handler will update focus

            // proxy for the contained composite

            hookFocusChangedEvent();

        }

        // start to monitor mouse up event because composite can have button

        // or text editor

        // which needs sending selection event or launching virtual keypad

        // for it when tapping on a internal label

        enableMouseEventListening();

    } else {

        if (focusSignalProxy > 0) {

            // delete focus proxy object and stop monitoring focus change

            // event if contained control is no longer a composite

            QObjectDeleteWrapper.deleteSafely(focusSignalProxy);

            focusSignalProxy = 0;

        }

        // update labels focus policy according to the focus policy of

        // contained control

        int controlClickFocusPolicy = OS

                .QWidget_focusPolicy(Internal_PackageSupport

                        .handle(control))

                & OS.QT_FOCUSPOLICY_CLICKFOCUS;

        if (controlClickFocusPolicy != (policy & OS.QT_FOCUSPOLICY_CLICKFOCUS)) {

            policy |= controlClickFocusPolicy;

            OS.QWidget_setFocusPolicy(Internal_PackageSupport

                    .handle(imageLabel), policy);

            OS.QWidget_setFocusPolicy(Internal_PackageSupport

                    .topHandle(titleLabel), policy);

            OS.QWidget_setFocusPolicy(Internal_PackageSupport

                    .topHandle(trailLabel), policy);

        }

        // update focus proxies of internal labels according to contained

        // control focus policy

        if (controlClickFocusPolicy != 0) {

            OS.QWidget_setFocusProxy(Internal_PackageSupport

                    .topHandle(imageLabel), Internal_PackageSupport

                    .topHandle(control));

            OS.QWidget_setFocusProxy(Internal_PackageSupport

                    .topHandle(titleLabel), Internal_PackageSupport

                    .topHandle(control));

            OS.QWidget_setFocusProxy(Internal_PackageSupport

                    .topHandle(trailLabel), Internal_PackageSupport

                    .topHandle(control));

        } else {