/**

 * Copyright (c) 2009-2010 Symbian Foundation and/or its subsidiary(-ies).

 * All rights reserved.

 * This component and the accompanying materials are made available

 * under the terms of the License "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:

 * Symbian Foundation - initial contribution.

 * Contributors:

 */

/*

IMPORTANT:  The Nokia software ("WRTKit and Example Widget files") is supplied to you by Nokia

and/or redistribution of the WRTKit and Example Widget files constitutes acceptance of these terms. If

you do not agree with these terms, please do not use, install, or redistribute the WRTKit and Example

Widget files.

In consideration of your agreement to abide by the following terms, and subject to these terms, Nokia

Widget files, to use, reproduce, and redistribute the WRTKit and Example files, in text form (for HTML,

CSS, or JavaScript files) or binary form (for associated images), for the sole purpose of creating S60

Widgets.

If you redistribute the WRTKit and Example files, you must retain this entire notice in all such

redistributions of the WRTKit and Example files.

You may not use the name, trademarks, service marks or logos of Nokia to endorse or promote products

that include the WRTKit and Example files without the prior written explicit agreement with Nokia.

Except as expressly stated in this notice, no other rights or licenses, express or implied, are granted by

Nokia herein, including but not limited to any patent rights that may be infringed by your products that

incorporate the WRTKit and Example files or by other works in which the WRTKit and Example files

may be incorporated.

The WRTKit and Example files are provided on an "AS IS" basis.  NOKIA MAKES NO

WARRANTIES, EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION THE IMPLIED

WARRANTIES OF NON-INFRINGEMENT, MERCHANTABILITY AND FITNESS FOR A

PARTICULAR PURPOSE, REGARDING THE EXAMPLES OR ITS USE AND OPERATION

ALONE OR IN COMBINATION WITH YOUR PRODUCTS.

IN NO EVENT SHALL NOKIA BE LIABLE FOR ANY SPECIAL, INDIRECT, INCIDENTAL OR

CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF

SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS

INTERRUPTION) ARISING IN ANY WAY OUT OF THE USE, REPRODUCTION, AND/OR

DISTRIBUTION OF THE EXAMPLES, HOWEVER CAUSED AND WHETHER UNDER THEORY

OF CONTRACT, TORT (INCLUDING NEGLIGENCE), STRICT LIABILITY OR OTHERWISE,

EVEN IF NOKIA HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

*/

///////////////////////////////////////////////////////////////////////////////

// The UI manager manages a set of views and other user interface elements.

// Constructor.

function UIManager(viewParentElement, scrollbarParentElement, enableScrollBar, delayInit) {    

    uiLogger.debug("UIManager(" + viewParentElement + ", " + scrollbarParentElement + ")");

    if (delayInit == null) {

        this.init(viewParentElement, enableScrollBar, scrollbarParentElement);

    }

}

// Parent element for views.

UIManager.prototype.viewParentElement = null;

// Parent element for scrollbar.

UIManager.prototype.scrollbarParentElement = null;

// The currently displayed view.

UIManager.prototype.currentView = null;

// Reference to the scrollbar.

UIManager.prototype.scrollbar = null;

// Current scroll Y position.

UIManager.prototype.scrollY = -1;

// Current viewport height.

UIManager.prototype.viewportHeight = -1;

// Current document height.

UIManager.prototype.documentHeight = -1;

// Timer identifier or null if no active timer.

UIManager.prototype.timerId = null;

// Interval for timer ticks for the UI manager timer (in milliseconds)

UIManager.prototype.TIMER_INTERVAL = 250;

// Reference to the notification popup used to displays notifications.

UIManager.prototype.notificationPopup = null;

// is scrollbar enabled

UIManager.prototype.enableScrollBar = null;

// init function

UIManager.prototype.init = function(viewParentElement, enableScrollBar, scrollbarParentElement) {

    this.enableScrollBar = enableScrollBar;

    // parent element for views

    if (viewParentElement == null) {

        // create a parent for views

        this.viewParentElement = document.createElement("div");

        this.viewParentElement.className = "ViewContainer";

        document.body.appendChild(this.viewParentElement);

    }

    else {

        this.viewParentElement = viewParentElement;

    }

    // parent element for scrollbar

    if (enableScrollBar) {

        if (scrollbarParentElement == null) {

            // create a parent for the scrollbar

            this.scrollbarParentElement = document.createElement("div");

            this.scrollbarParentElement.className = "DocumentScrollbarContainer";

            document.body.appendChild(this.scrollbarParentElement);

        }

        else {

            this.scrollbarParentElement = scrollbarParentElement;

        }

    }

    // currently selected view

    this.currentView = null;

    // create the notification popup

    // the notification popup adds itself as a child element to the document body

    this.notificationPopup = new NotificationPopup();

    // create scrollbar

    if (enableScrollBar) {

        this.scrollbar = new Scrollbar(this.scrollbarParentElement);

    }

    // setup scrollbar tracking

    var self = this;

    this.startTimer();

    if (enableScrollBar) {

        window.addEventListener("resize", function(){

            self.updateScrollbar();

        }, false);

        window.addEventListener("scroll", function(){

            self.updateScrollbar();

        }, false);

    }

};

// Returns the current view.

UIManager.prototype.getView = function() {

    return this.currentView;

};

// Switches to the specified view.

UIManager.prototype.setView = function(view) {

    uiLogger.debug("View set to " + view.id);

    // remove the current view from the parent element

    if (this.currentView != null) {

        this.viewParentElement.removeChild(this.currentView.rootElement);

    }

    // reset scroll

    window.scrollTo(0, 0);

    // add the new view to the parent element

    if (view != null) {

        this.currentView = view;

        this.currentView.resetControlFocusStates();

        this.viewParentElement.appendChild(this.currentView.rootElement);

    }

    // update scrollbar

    if (this.enableScrollBar) {

        this.updateScrollbar();

    }

    // focus the first focusable control

    // a timer is used to prevent unwanted focus shift

    setTimeout(function() { view.focusFirstControl(); }, 1);

};

// Updates the scrollbar.

UIManager.prototype.updateScrollbar = function() {

    if (this.enableScrollBar) {

        // get current viewport and document position and dimensions

        var scrollY = window.scrollY;

        var viewportHeight = window.innerHeight;

        var documentHeight = Math.max(document.documentElement.scrollHeight, document.height);

        // check if the scroll position or view has changed

        if (this.scrollY != scrollY ||

                this.viewportHeight != viewportHeight ||

                this.documentHeight != documentHeight) {

            // scroll position or view has changed

            this.scrollY = scrollY;

            this.viewportHeight = viewportHeight;

            this.documentHeight = documentHeight;

            // update the scrollbar

            this.scrollbar.update(scrollY, viewportHeight, documentHeight);

            uiLogger.debug("Scrollbar updated");

        }

    }

};

// Starts the view manager timer.

UIManager.prototype.startTimer = function() {

    if (this.timerId == null) {

        uiLogger.debug("UIManager timer started");

        var self = this;

        // setup the timer

        this.timerId = setInterval(function() { self.onTimer(); }, this.TIMER_INTERVAL);

    } else {

        uiLogger.warn("UIManager timer already running");

    }

};

// Stops the view manager timer.

UIManager.prototype.stopTimer = function() {

    if (this.timerId != null) {

        // stop the timer

        clearTimeout(this.timerId);

        this.timerId = null;

    } else {

        uiLogger.warn("UIManager timer already stopped");

    }

};

// Timer callback function.

UIManager.prototype.onTimer = function() {

    if (this.enableScrollBar) {

        // make sure the scrollbar is up to date

        this.updateScrollbar();

    }

};

// Displays a notification.

UIManager.prototype.showNotification = function(displayTime, type, text, progress) {

    uiLogger.debug("UIManager.showNotification(" + displayTime + ", " + type + ", " + text + ", " + progress + ")");

    // use the notification popup to show the notification

    this.notificationPopup.showNotification(displayTime, type, text, progress);

};

// Hides the currently displayed notification.

UIManager.prototype.hideNotification = function() {

    uiLogger.debug("UIManager.hideNotification()");

    // hide the notification popup

    this.notificationPopup.hideNotification();

};