/*

* Copyright (c) 2008-2010 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 com.nokia.mj.impl.installer.ui.eswt;

import org.eclipse.swt.custom.ScrolledComposite;

import org.eclipse.swt.SWT;

import org.eclipse.swt.graphics.Image;

import org.eclipse.swt.graphics.Point;

import org.eclipse.swt.graphics.Rectangle;

import org.eclipse.swt.layout.GridData;

import org.eclipse.swt.layout.GridLayout;

import org.eclipse.swt.widgets.Composite;

import org.eclipse.swt.widgets.Display;

import org.eclipse.swt.widgets.Label;

import org.eclipse.swt.widgets.Shell;

/**

 * Base class for different InstallerUi views.

 */

abstract public class ViewBase

{

    /** Maximum view height in percentage from display client area height. */

    protected static final int MAX_VIEW_HEIGHT = 80;

    /** Parent shell for this view. */

    protected Shell iParent = null;

    /** Container for the contents of the view */

    private Composite iContainer = null;

    /** ScrolledComposite for iComposite. */

    private ScrolledComposite iScrolledComposite = null;

    /** Composite to which subclasses add their widgets. */

    private Composite iComposite = null;

    /** Composite to which command buttons are added. */

    private Composite iCommandComposite = null;

    /** InstallerUi owning this view. */

    protected InstallerUiEswt iInstallerUi = null;

    /** True if this view is visible. */

    private boolean iVisible = false;

    /** Number of columns for this view's GridLayout. */

    private int iColumns = 1;

    /** Default content size. */

    private Point iDefaultContentSize = null;

    /** Constructor */

    protected ViewBase()

    {

    }

    /** Constructor */

    protected ViewBase(InstallerUiEswt aInstaller, Composite aParent, int aColumns)

    {

        iInstallerUi = aInstaller;

        // Each view gets a separate shell as a parameter.

        iParent = (Shell)aParent;

        iContainer = new Composite(iParent, 0);

        iContainer.setVisible(false);

        iColumns = aColumns;

        // Store the default bounds for later height adjustments.

        Rectangle defShellBounds = iInstallerUi.defaultShellBounds();

        Rectangle defShellClientBounds = iInstallerUi.defaultShellClientBounds();

        iContainer.setSize(defShellClientBounds.width, defShellClientBounds.height);

        // Let the scrolled composite fill the Shell.

        iContainer.setLayout(setZeroMargins(new GridLayout()));

        // Create a ScrolledComposite for views which need ScrollBars.

        iScrolledComposite = new ScrolledComposite(iContainer, getStyle());

        iScrolledComposite.setAlwaysShowScrollBars(false);

        iScrolledComposite.setExpandHorizontal(true);

        GridData gridData = new GridData(GridData.FILL_BOTH);

        iScrolledComposite.setLayoutData(gridData);

        // Create a composite for command buttons.

        iCommandComposite = new Composite(iContainer, SWT.NONE);

        GridLayout cmdLayout = setZeroMargins(new GridLayout(2, true));

        cmdLayout.marginTop = 5;

        iCommandComposite.setLayout(cmdLayout);

        gridData = new GridData(GridData.FILL_HORIZONTAL);

        iCommandComposite.setLayoutData(gridData);

        // Layout now and get the default size of the content area

        iContainer.layout(true);

        Rectangle rect = iScrolledComposite.getClientArea();

        iDefaultContentSize = new Point(rect.width, rect.height);

        // Create the content composite.

        iComposite = new Composite(iScrolledComposite, SWT.NONE);

        iComposite.setLayout(new GridLayout(getColumns(), true));

        iScrolledComposite.setContent(iComposite);

    }

    /**

     * Returns composite which holds the contents of this view.

     */

    public Composite getContainer()

    {

        return iContainer;

    }

    /** Returns composite to which subclasses can add their widgets. */

    public Composite getComposite()

    {

        return iComposite;

    }

    /** Returns ScrolledComposite for Composite. */

    public ScrolledComposite getScrolledComposite()

    {

        return iScrolledComposite;

    }

    /** Returns composite to which command buttons are added. */

    public Composite getCommandComposite()

    {

        return iCommandComposite;

    }

    /** Returns a shell for this view. */

    public Shell getShell()

    {

        return iParent;

    }

    /** Returns display for this view. */

    public Display getDisplay()

    {

        return getShell().getDisplay();

    }

    /**

     * Returns title for this view. If the title has not been

     * set, returns an empty string.

     */

    public String getTitle()

    {

        return iParent.getText();

    }

    /** Set title for this view. */

    public void setTitle(String aTitle)

    {

        // Dialog shells have no title anymore

    }

    /** Disposes this view. */

    public void dispose()

    {

        // This must be final because it is used from inner class.

        final String className = this.toString();

        log(className + ": disposing");

        // UI updates must be executed in UI thread.

        iParent.getDisplay().syncExec

        (new Runnable()

        {

            public void run()

            {

                if (!isDisposed())

                {

                    log(className + ": disposing view container");

                    iContainer.dispose();

                }

            }

        });

    }

    /** Returns true this view has been disposed, false otherwise. */

    public boolean isDisposed()

    {

        if (iContainer.isDisposed())

        {

            return true;

        }

        return false;

    }

    /** Set this view visible. Any previously visible view will be hidden.

     *  The size of the dialog Shell host will be changed to fit this view.*/

    public void setVisible(boolean aVisible)

    {

        if (iVisible == aVisible)

        {

            return;

        }

        log(this.toString() + ": setVisible " + aVisible);

        iVisible = aVisible;

        if (iVisible)

        {

            iInstallerUi.setActiveView(this);

        }

        else

        {

            if (iInstallerUi.getActiveView() == this)

            {

                iInstallerUi.setActiveView(null);

            }

        }

        // UI updates must be executed in UI thread.

        iParent.getDisplay().syncExec(new Runnable()

        {

            public void run()

            {

                if (isDisposed())

                {

                    return;

                }

                if (iVisible)

                {

                    updateSize();

                }

                iContainer.setVisible(iVisible);

                if (iVisible)

                {

                    if (iParent.getDisplay().getActiveShell() != iParent)

                    {

                        iParent.open();

                    }

                    if (!iParent.isVisible())

                    {

                        iParent.setVisible(true);

                    }

                    if (forceFocusToView())

                    {

                        iContainer.forceFocus();

                    }

                }

            }

        });

    }

    /** Returns true if this view is visible, false otherwise. */

    public boolean isVisible()

    {

        return iVisible;

    }

    /** Sets the view size according to display size. */

    protected void updateSize()

    {

        getShell().setRedraw(false);

        // First calculate size without vertical scrollbar.

        doUpdateSize(false);

        if (getScrolledComposite().getVerticalBar() != null &&

                getScrolledComposite().getVerticalBar().getVisible())

        {

            // If scrollbar is visible recalculate size with scrollbar.

            doUpdateSize(true);

        }

        getShell().setRedraw(true);

    }

    /** Sets the view size according to display size. */

    private void doUpdateSize(boolean aVerticalScrollBarVisible)

    {

        Shell shell = getShell();

        Composite comp = getComposite();

        Composite cmdComp = getCommandComposite();

        int contentWidth = iDefaultContentSize.x;

        if (aVerticalScrollBarVisible)

        {

            int verticalScrollBarWidth =

                getScrolledComposite().getVerticalBar().getSize().x;

            contentWidth = iDefaultContentSize.x - verticalScrollBarWidth;

        }

        // Recalculate size of the content.

        Point contentSize = comp.computeSize(contentWidth, SWT.DEFAULT);

        comp.setSize(contentSize);

        Point cmdContentSize = cmdComp.computeSize(iDefaultContentSize.x, SWT.DEFAULT);

        // Adjust Shell height. The Shell never changes the x position, nor the width.

        Rectangle dispRect = shell.getDisplay().getClientArea();

        int offset = iDefaultContentSize.y - contentSize.y - cmdContentSize.y;

        Rectangle defShellBounds = iInstallerUi.defaultShellBounds();

        int newHeight = defShellBounds.height - offset;

        int maxHeight = dispRect.height * MAX_VIEW_HEIGHT / 100;

        if (newHeight > maxHeight)

        {

            offset -= maxHeight - newHeight;

            newHeight = maxHeight;

        }

        Rectangle dispBounds = shell.getDisplay().getBounds();

        int y = dispBounds.height - newHeight;

        // For landscape orientation center vertically

        if (dispRect.width > dispRect.height)

        {

            y /= 2;

        }

        // Set bounds when command Buttons are in use.

        shell.setBounds(defShellBounds.x, y, defShellBounds.width, newHeight);

        Rectangle clientArea = shell.getClientArea();

        iContainer.setSize(clientArea.width, clientArea.height);

        iContainer.layout(true);

    }

    /**

     * Called when screen orientation changes.

     */

    protected void screenOrientationChanged()

    {

        updateSize();

    }

    /**

     * Returns true if the View should have focus after it has been opened.

     */

    protected boolean forceFocusToView()

    {

        return true;

    }

    /**

     * Returns SWT style for this view. Subclasses should override

     * this method to return style with SWT.H_SCROLL and/or SWT.V_SCROLL

     * if they need scrollbars.

     */

    protected int getStyle()

    {

        return SWT.NONE;

    }

    /**

     * Returns number of columns for this view.

     */

    protected int getColumns()

    {

        return iColumns;

    }

    /**

     * Creates a new label with given text and adds it to this view.

     * The created label takes one column from this view's GridLayout.

     *

     * @param aText text for the label

     * @param aStyle SWT style for the label

     * @return label that was added to this view

     */

    protected Label createLabel(String aText, int aStyle)

    {

        return createLabel(aText, getColumns(), aStyle);

    }

    /**

     * Creates a new label with given text and adds it to this view.

     *

     * @param aText text for the label

     * @param aColumns number of columns the label takes

     * @param aStyle SWT style for the label

     * @return label that was added to this view

     */

    protected Label createLabel(String aText, int aColumns, int aStyle)

    {

        Label label = new Label(getComposite(), aStyle);

        label.setText(aText);

        GridData gridData = new GridData(GridData.FILL_HORIZONTAL);

        gridData.horizontalSpan = aColumns;

        label.setLayoutData(gridData);

        return label;

    }

    /**

     * Creates a new label with given image and adds it to this view.

     * The created label takes one column from this view's GridLayout.

     *

     * @param aImage image for the label

     * @param aStyle SWT style for the label

     * @return label that was added to this view

     */

    protected Label createLabel(Image aImage, int aStyle)

    {

        return createLabel(aImage, getColumns(), aStyle);

    }

    /**

     * Creates a new label with given image and adds it to this view.

     * The created label takes one column from this view's GridLayout.

     *

     * @param aImage image for the label

     * @param aColumns number of columns the label takes

     * @param aStyle SWT style for the label

     * @return label that was added to this view

     */

    protected Label createLabel(Image aImage, int aColumns, int aStyle)

    {

        Label label = new Label(getComposite(), aStyle);

        label.setImage(aImage);

        GridData gridData = new GridData(GridData.FILL_HORIZONTAL);

        gridData.horizontalSpan = aColumns;

        gridData.horizontalAlignment = SWT.CENTER;

        gridData.verticalAlignment = SWT.TOP;

        label.setLayoutData(gridData);

        return label;

    }

    /**

     * Creates a new label with security icon.

     *

     * @param aIdentified true if security icon is for an

     * identified application, false otherwise

     * @return label that was added to this view

     */

    protected Label createSecurityLabel(boolean aIdentified)

    {

        Label label = createLabel((Image)null, 1, SWT.NONE);

        Image securityIcon = null;

        if (iInstallerUi != null)

        {

            securityIcon = iInstallerUi.getSecurityIcon(

                getDisplay(), aIdentified);

        }

        if (securityIcon != null)

        {

            label.setImage(securityIcon);

        }

        else

        {

            label.setText(aIdentified? "I": "U");

        }

        return label;

    }

    /**

     * Sets margins and spacing for the given layout to zero.

     */

    protected GridLayout setZeroMargins(GridLayout aLayout)

    {

        aLayout.horizontalSpacing = 0;

        aLayout.verticalSpacing = 0;

        aLayout.marginBottom = 0;

        aLayout.marginTop = 0;

        aLayout.marginHeight = 0;

        aLayout.marginWidth = 0;

        aLayout.marginLeft = 0;

        aLayout.marginRight = 0;

        return aLayout;

    }

    protected void log(String aMsg)

    {

        if (iInstallerUi != null)

        {

            iInstallerUi.log(aMsg);

        }

    }

    protected void logError(String aMsg, Throwable aThrowable)

    {

        if (iInstallerUi != null)

        {

            iInstallerUi.logError(aMsg, aThrowable);

        }

    }

}