//
//  iWeb - HeaderControls.js
//  Copyright (c) 2007 Apple Inc. All rights reserved.
//

//
// HeaderControls
//
function HeaderControls(instanceID)
{
    if(instanceID != null)
    {
        Widget.apply(this, arguments);

        NotificationCenter.addObserver(this, HeaderControls.prototype.p_prevPage, "PreviousPage", this.p_mediaGridID());
        NotificationCenter.addObserver(this, HeaderControls.prototype.p_nextPage, "NextPage", this.p_mediaGridID());
        NotificationCenter.addObserver(this, HeaderControls.prototype.p_setPage, "SetPage", this.p_mediaGridID());

        this.mRange = new IWPageRange(0, 5);
        this.p_updateRange();
    }
}

// set up inheritance
HeaderControls.prototype = new Widget();
HeaderControls.prototype.constructor = HeaderControls;

// other subclass setup

HeaderControls.prototype.widgetIdentifier = "com-apple-iweb-widget-headercontrols";

HeaderControls.prototype.onload = function() 
{
    var defaults = {showBackToIndex: true,
                    showAddPhoto: true,
                    showSubscribe: true,
                    showSlideshow: true,
                    mediaIndex: false,
                    entriesPerPage: 99,
                    entryCount: 0};
    this.initializeDefaultPreferences(defaults);

    // Ensure that we start on page 0
    this.setPage(0);
    this.updateFromPreferences();
    
    if (this.preferences && this.preferences.postNotification)
    {
        this.preferences.postNotification("BLWidgetIsSafeToDrawNotification", 1);        
    }
}

HeaderControls.prototype.onunload = function() 
{
}

HeaderControls.prototype.startup = function()
{
    this.p_updateCanvasControls();
    this.p_updateBackToIndex();
    this.p_updatePaginationControls();
    this.p_updateAddPhoto();
    this.p_updateSubscribe();
    this.p_updateSlideshow();

    // Display either the media index- or album-specific controls
    if(this.p_mediaIndex())
    {
        this.getElementById("media_index_only").show();
    }
    else
    {
        this.getElementById("album_only").show();
    }
}

HeaderControls.prototype.changedPreferenceForKey = function(key)
{
    if(key == "entriesPerPage" || key == "entryCount" || key == "x-currentPage")
    {
        this.p_updateRange();
        this.p_updatePaginationControls();
    }
    else if(key == "showBackToIndex")
    {
        this.p_updateBackToIndex();
    }
    else if(key == "showAddPhoto")
    {
        this.p_updateAddPhoto();
    }
    else if(key == "showSubscribe")
    {
        this.p_updateSubscribe();
    }
    else if(key == "showSlideshow")
    {
        this.p_updateSlideshow();
    }
    else if(key == "canvas controls")
    {
        this.p_updateCanvasControls();
    }
    else if(this.runningInApp)
    {
        // These preferences only ever change in app, and are only ever set by the footer
        // widget, which shares a prefs model with us.
        if(key == "x-nextPage")
        {
            this.nextPage();
        }
        else if(key == "x-previousPage")
        {
            this.prevPage();
        }
        else if(key == "x-setPage")
        {
            this.setPage(this.p_setPagePreference());
        }
    }
}

HeaderControls.prototype.updateFromPreferences = function()
{
    this.startup();
}

HeaderControls.prototype.prevPage = function()
{
    NotificationCenter.postNotification(new IWNotification("PreviousPage", this.p_mediaGridID(), null));
}

HeaderControls.prototype.nextPage = function()
{
    NotificationCenter.postNotification(new IWNotification("NextPage", this.p_mediaGridID(), null));
}

HeaderControls.prototype.setPage = function(pageIndex)
{
    NotificationCenter.postNotification(new IWNotification("SetPage", this.p_mediaGridID(), {pageIndex: pageIndex}));
}

HeaderControls.prototype.playSlideshow = function()
{
    if(this.mPlaySlideshowFunction)
    {
        this.mPlaySlideshowFunction();
    }
}

HeaderControls.prototype.setPlaySlideshowFunction = function(playSlideshow)
{
    this.mPlaySlideshowFunction = playSlideshow;
}


// Private accessors

HeaderControls.prototype.p_canNavigateToPrev = function()
{
    return (this.p_currentPage() > 0);
}

HeaderControls.prototype.p_prevPage = function(notification)
{
    if(this.p_canNavigateToPrev())
    {
        this.setPage(this.p_currentPage() - 1);
    }
}

HeaderControls.prototype.p_canNavigateToNext = function()
{
    return (this.p_currentPage() < this.p_pageCount()-1);
}

HeaderControls.prototype.p_nextPage = function(notification)
{
    if(this.p_canNavigateToNext())
    {
        this.setPage(this.p_currentPage() + 1);
    }
}

HeaderControls.prototype.p_setPage = function(notification)
{
    var pageIndex = notification.userInfo().pageIndex;
    this.setPreferenceForKey(pageIndex, "x-currentPage");

    // When published, need to send a range changed notification here to (potentially)
    // reload the stream and re-layout the images.
    if(!this.runningInApp)
    {
        var entriesPerPage = this.p_entriesPerPage();
        var location = pageIndex * entriesPerPage;
        var length = Math.min(this.p_entryCount() - location, entriesPerPage);
        var userInfo = { "range" : new IWRange(location, length) };
        NotificationCenter.postNotification(new IWNotification("RangeChanged", this.p_mediaGridID(), userInfo));
    }
}


HeaderControls.prototype.p_showBackToIndex = function()
{
    var show = this.preferenceForKey("showBackToIndex");
    (function(){return show !== undefined}).assert();

    return show;
}

HeaderControls.prototype.p_showAddPhoto = function()
{
    var show = this.preferenceForKey("showAddPhoto");
    (function(){return show !== undefined}).assert();

    return show;
}

HeaderControls.prototype.p_showSubscribe = function()
{
    var show = this.preferenceForKey("showSubscribe");
    (function(){return show !== undefined}).assert();

    return show;
}

HeaderControls.prototype.p_showSlideshow = function()
{
    var show = this.preferenceForKey("showSlideshow");
    (function(){return show !== undefined}).assert();

    return show;
}

HeaderControls.prototype.p_mediaGridID = function()
{
    var mediaGridID = null;

    if(this.preferences)
    {
        mediaGridID = this.preferenceForKey("gridID");
    }

    if(mediaGridID === undefined)
    {
        mediaGridID = null;
    }

    return mediaGridID;
}

HeaderControls.prototype.p_setPagePreference = function()
{
    var setPagePreference = null;

    if(this.preferences)
    {
        setPagePreference = this.preferenceForKey("x-setPage");
    }

    if(setPagePreference === undefined)
    {
        setPagePreference = null;
    }

    return setPagePreference;
}


HeaderControls.prototype.p_updatePaginationControls = function()
{
    var widgetDiv = this.div();
    var currentPage = this.p_currentPage();

    // Build the navigation elements    
    var controls = "";
    
    if(this.p_isPaginated())
    {
        // Left arrow
        var canvasControlURLs = this.preferenceForKey("canvas controls");
        if(this.p_canNavigateToPrev())
        {
            var leftArrowSrc = canvasControlURLs['canvas_arrow-left'];
            controls += "<a href='javascript:#{WIDGET_ID}.prevPage()'>";
            controls += imgMarkup(leftArrowSrc, '', '', '');
            controls += "</a> ";
        }
        else
        {
            var leftArrowSrc = canvasControlURLs['canvas_arrow-left-D'];
            controls += imgMarkup(leftArrowSrc, '', '', '') + " ";
        }

        // Page entries
        for(var i=this.mRange.min(); i<this.mRange.max(); i++)
        {
            if(i == currentPage)
            {
                controls += "<span class='current_page'>" + (i+1) + "</span> ";
            }
            else
            {
                controls += "<a href='javascript:#{WIDGET_ID}.setPage(" + i + ")'>" + (i+1) + "</a> ";
            }
        }
    
        // Right arrow
        if(this.p_canNavigateToNext())
        {
            var rightArrowSrc = canvasControlURLs[ 'canvas_arrow-right'];
            controls += "<a href='javascript:#{WIDGET_ID}.nextPage()'>";
            controls += imgMarkup(rightArrowSrc, '', '', '');
            controls += "</a>";
        }
        else
        {
            var rightArrowSrc = canvasControlURLs[ 'canvas_arrow-right-D'];
            controls += imgMarkup(rightArrowSrc, '', '', '');
        }
    }
    
    var template = new Template(controls);
    var myControls = template.evaluate({WIDGET_ID: this.instanceID});
    this.getElementById("pagination_controls").update(myControls);

    // Handle pagination element layout
    widgetDiv.getElementsByClassName("paginated_only").invoke(this.p_isPaginated() ? 'show' : 'hide');
    widgetDiv.getElementsByClassName("non_paginated_only").invoke(this.p_isPaginated() ? 'hide' : 'show');

    // Communicate the contents of the pagination control indirectly to the footer control,
    // via either the shared prefs bridge, or a notification.
    if(this.runningInApp)
    {
        this.setPreferenceForKey(controls, "x-paginationSpanContents");
    }
    else
    {
        NotificationCenter.postNotification(new IWNotification("paginationSpanContents", this.p_mediaGridID(), {controls: controls}));
    }
}

HeaderControls.prototype.p_setAnchorsUnderElementToHREF = function(element, href)
{
    var links = element.getElementsByTagName("a");
    for(var i = 0; i < links.length; ++i)
    {
        links[i].href = href;
    }
}

HeaderControls.prototype.p_updateCanvasControls = function()
{
    var canvasControlURLs = this.preferenceForKey("canvas controls");
    this.div().getElementsByClassName('canvas').each(function(img)
    {
        var canvasControlName = "canvas_" + img.classNames().toArray()[1];
        setImgSrc(img, canvasControlURLs[canvasControlName]);
    });
}

HeaderControls.prototype.p_updateBackToIndex = function()
{
    var element = this.getElementById("back_to_index");
    this.p_showBackToIndex() ? element.show() : element.hide();
    if(!this.runningInApp)
    {
        this.p_setAnchorsUnderElementToHREF(element, this.p_indexURL());
    }
}

HeaderControls.prototype.p_updateAddPhoto = function()
{
    var element = this.getElementById("add_photo");
    this.p_showAddPhoto() ? element.show() : element.hide();
    if(!this.runningInApp)
    {
        // TODO (mm) -- hook up add a photo
        this.p_setAnchorsUnderElementToHREF(element, "javascript:(void)");
    }
}

HeaderControls.prototype.p_updateSubscribe = function()
{
    this.div().getElementsByClassName("subscribe").invoke(this.p_showSubscribe() ? 'show' : 'hide');
    if(!this.runningInApp)
    {
		var feedURL = "javascript:" + this.instanceID + (this.p_mediaIndex() ? ".mediaIndexSubscribe()" : ".photocastSubscribe()")
        var self = this;
        this.div().getElementsByClassName("subscribe").each(function(element)
        {
            self.p_setAnchorsUnderElementToHREF(element, feedURL);
        });
    }
}


HeaderControls.prototype.mediaIndexSubscribe = function()
{
	window.location = this.p_feedURL();
}

HeaderControls.prototype.photocastSubscribe = function()
{
	photocastHelper(this.p_feedURL());
}

HeaderControls.prototype.p_updateSlideshow = function()
{
    this.div().getElementsByClassName("play_slideshow").invoke(this.p_showSlideshow() ? 'show' : 'hide');
}

HeaderControls.prototype.p_mediaIndex = function()
{
    var mediaIndex = null;

    if(this.preferences)
    {
        mediaIndex = this.preferenceForKey("mediaIndex");
    }

    if(mediaIndex === undefined)
    {
        mediaIndex = false;
    }

    return mediaIndex;
}

HeaderControls.prototype.p_currentPage = function()
{
    var currentPage = 0;

    if(this.preferences)
    {
        currentPage = this.preferenceForKey("x-currentPage");
    }

    if(!currentPage)
    {
        currentPage = 0;
    }

    return currentPage;
}

HeaderControls.prototype.p_entriesPerPage = function()
{
    var entriesPerPage = null;

    if(this.preferences)
    {
        entriesPerPage = this.preferenceForKey("entriesPerPage");
    }

    if(entriesPerPage == undefined)
    {
        entriesPerPage = 99;
    }

    return entriesPerPage;
}

HeaderControls.prototype.p_entryCount = function()
{
    var entryCount = null;

    if(this.preferences)
    {
        entryCount = this.preferenceForKey("entryCount");
    }

    if(entryCount == undefined)
    {
        entryCount = 0;
    }

    return entryCount;
}

HeaderControls.prototype.p_indexURL = function()
{
    return this.preferenceForKey("indexURL");
}

HeaderControls.prototype.p_feedURL = function()
{
    return this.preferenceForKey("feedURL");
}


HeaderControls.prototype.p_isPaginated = function()
{
    return (this.p_entryCount() > this.p_entriesPerPage());
}

HeaderControls.prototype.p_pageCount = function()
{
    return Math.ceil(this.p_entryCount() / this.p_entriesPerPage());
}

HeaderControls.prototype.p_updateRange = function()
{
    var pageCount = this.p_pageCount();
    var currentPage = this.p_currentPage();

    // Ensure that the current page is valid.
    if(currentPage >= pageCount)
    {
        currentPage = pageCount-1;
        this.setPreferenceForKey(currentPage, "x-currentPage");
    }

    // Keep our range valid for the given page count.  Also handle bootstrapping the range when
    // it starts small.
    if(pageCount <= 5 || this.mRange.length() < 3 || this.mRange.max() > pageCount)
    {
        this.mRange.setMax(Math.min(5, pageCount));
    }

    // Keep the current page visible
    if(currentPage < this.mRange.min())
    {
        this.mRange.shift(currentPage - this.mRange.min());
    }
    else if(currentPage >= this.mRange.max())
    {
        this.mRange.shift(currentPage - this.mRange.max() + 1);
    }
}