/*
* Copyright (c) 2005 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.microedition.media;

import javax.microedition.media.Control;
import javax.microedition.media.Controllable;
import com.nokia.microedition.media.control.ControlImpl;
import javax.microedition.media.Player;
import java.util.Hashtable;
import java.util.Enumeration;
import com.nokia.mj.impl.utils.Logger;

/**
 * ControlContainer class creates java control objects according to a classname
 * which is got from native control object. Created controls are accessible
 * through Controllable interface which is implemented in this class.
 */
public class ControlContainer implements Controllable
{
    /**
     * Default control package. Used when getting control with
     * getControl method which appends default control package if package is
     * not specified.
     */
    static final String CONTROL_DEFAULT_PACKAGE =
        "javax.microedition.media.control.";


    /**
     * Default control package. Used when getting control with
     * getControl method which appends default control package if package is
     * not specified.
     */
    static final String CONTROL_IMPLEMENTATION_PACKAGE =
        "com.nokia.microedition.media.control.";
    /**
     * Hashtable containing controls identified with a full package name.
     * All control names starts with iDefaultPackage.
     */
    private final Hashtable iControls = new Hashtable();

    /**
     * Creates new ControlContainer.
     */
    private ControlContainer()
    {
    }

    /**
     * Create new ControlContainer and populates the controls.
     *
     * If native control name does not contain package name default
     * com.nokia.microedition.media.control. package is used.
     * If control name starts with . (.package.ClassName), Java control is not
     * created. If control name contains valid package name and classname Java
     *instance will be created.
     *
     *
     * @param aPlayer Player which will contain the controls.
     * @param aEventSourceHandle Handle to native event source.
     * @param aNativeHandle Handle to native control source.
     */
    public static final ControlContainer populateControls(
        Player aPlayer,
        int aEventSourceHandle,
        int aNativeHandle)
    {
        ControlContainer container = new ControlContainer();

        // Get amount of controls in native object.
        int controlCount = _getControlsCount(aNativeHandle);

        // Create java object for each native objects.
        for (int i = 0; i < controlCount; i++)
        {
            // Get handle to native object at index i
            int controlHandle = _getControlHandle(aNativeHandle,
                                                  i);

            // Get public class name for the control.
            String realClassName = _getPublicControlClassName(controlHandle);

            // If null public control name was returned, Java control is not
            // created. This allows extensions to use existing Player's
            // native control array.
            if (realClassName == null)
            {
                continue;
            }

            // Get the implementation class name for the control which will
            // be used to create java object.
            String className = _getControlClassName(controlHandle);

            // Add package if it does not exists
            if (className.indexOf('.') < 0)
            {
                className = CONTROL_IMPLEMENTATION_PACKAGE + className;
                realClassName = CONTROL_DEFAULT_PACKAGE + className;
            }

            // create java instance
            Control control = createControl(aPlayer,
                                            className,
                                            controlHandle,
                                            aEventSourceHandle);
            container.iControls.put(realClassName, control);
        }

        // population succeed, return created collection
        return container;
    }

    /**
     * Adds new control
     */
    public void addControl(Control aControl, String aControlName)
    {
        iControls.put(aControlName, aControl);
    }

    /**
     * Disposes all the controls
     */
    public void dispose()
    {
        Enumeration controls = iControls.elements();
        while (controls.hasMoreElements())
        {
            Object control = controls.nextElement();

            // only ControlImpl derived classes need to be notified.
            if (control instanceof ControlImpl)
            {
                ((ControlImpl)control).notifyDispose();
            }
        }
    }

    /**
     * Implements method defined in javax.microedition.media.Controllable.
     *
     * @see javax.microedition.media.Controllable
     * @param aControlType  the class name of the Control. The class name should
     * be given either as the fully-qualified name of the class; or if the
     * package of the class is not given, the package
     * javax.microedition.media.control is assumed.
     * @return the object that implements the control, or null.
     */
    public Control getControl(String aControlType)
    {
        if (aControlType == null)
        {
            throw new IllegalArgumentException("argument is null");
        }

        String controlType = aControlType;

        // check if package name exists
        if (controlType.indexOf(".") == -1)
        {
            // add package name
            controlType = CONTROL_DEFAULT_PACKAGE + aControlType;
        }
        Control control = (Control)iControls.get(controlType);

        // If control does not exists with default name, check if there is
        // is a control with same type ( extends the given class name ).
        if (control == null)
        {
            try
            {
                // try to create class for control
                Class controlClass = Class.forName(controlType);

                Enumeration elements = iControls.elements();

                // search if any control is same type that requested control
                while (elements.hasMoreElements() &&
                        control == null)
                {
                    Control tmpControl = (Control)elements.nextElement();
                    if (controlClass.isInstance(tmpControl))
                    {
                        // control is found
                        control = tmpControl;
                    }
                }
            }
            catch (ClassNotFoundException cnfe)  // the class could not be found
            {
                // Exception is ignored and null is returned from this method
                Logger.ELOG(Logger.EJavaMMAPI,
                            "ControlContainer::getControl ", cnfe);
            }
            catch (Error e)  // the function failed for any other reason.
            {
                // Error is ignored and null is returned from this method
                Logger.ELOG(Logger.EJavaMMAPI,
                            "ControlContainer::getControl " , e);
            }
        }
        return control;
    }

    /**
     * Implements method defined in javax.microedition.media.Controllable.
     *
     * @see javax.microedition.media.Controllable
     * @return the collection of Control objects.
     */
    public Control[] getControls()
    {
        Control[] controls = new Control[ iControls.size()];
        Enumeration elements = iControls.elements();
        int i = 0;
        // Put all controls to array
        while (elements.hasMoreElements())
        {
            controls[ i ] = (Control)elements.nextElement();
            i++;
        }
        return controls;
    }

    /**
     * Creates new Control instance.
     * All control classes must be in iPrivatePackage package and
     * extend the ControlImpl base class. Created control is initialized
     * with native control handle and eventsource handle.
     *
     * @param aPlayer Player which will contain the controls.
     * @param aClassName Control's class name without the package.
     * @param aControlHandle Handle to native control.
     * @param aEventSourceHandle Handle to native control source.
     * @return created control
     */
    static private final Control createControl(Player aPlayer,
            String aClassName,
            int aControlHandle,
            int aEventSourceHandle)
    {
        ControlImpl control = null;

        // Try to make control instance. If instantion fails, it is an internal
        // error and can only occur in development time.
        try
        {
            Class controlClass =
                Class.forName(aClassName);
            control = (ControlImpl)controlClass.newInstance();
            control.setHandles(aPlayer, aEventSourceHandle, aControlHandle);
        }
        catch (InstantiationException ie)
        {
            throw new OutOfMemoryError("Instantiation failed, " + ie.getMessage());
        }
        catch (IllegalAccessException iae)
        {
            throw new OutOfMemoryError("Illegal access, " + iae.getMessage());
        }
        catch (ClassNotFoundException cnfe)
        {
            throw new OutOfMemoryError("Class not found, " + cnfe.getMessage());
        }
        return control;
    }

    /**
     * Return the amount of controls in native control source.
     *
     * @param aNativeHandle Handle to native control source object.
     */
    private static native int _getControlsCount(int aNativeHandle);

    /**
     * Return native handle to control at specified index.
     *
     * @param aNativeHandle Handle to native control source object.
     * @param aControlIndex Control's index.
     */
    private static native int _getControlHandle(int aNativeHandle,
            int aControlIndex);


    /**
     * Returns the control class name that can be used to instantiate Java
     * object.
     *
     * @param aControlHandle Handle to native control.
     */
    private static native String _getControlClassName(int aControlHandle);

    /**
     * Returns the control class name that is the public name for the control.
     *
     * @param aControlHandle Handle to native control.
     */
    private static native String _getPublicControlClassName(int aControlHandle);

}