var Prezi = (function (my) {
    var preziPlayer = null;

    /**
     * Reloads the current presentation.
     */
    my.reloadPresentation = function() {
        var iframe = document.getElementById(preziPlayer.options.preziId);
        iframe.src = iframe.src;
    };

    /**
     * Shows/hides a presentation.
     */
    my.setPresentationVisible = function (visible) {
        if (visible) {
            // Trigger the video.selected event to indicate a change in the
            // large video.
            $(document).trigger("video.selected", [true]);

            $('#largeVideo').fadeOut(300, function () {
                setLargeVideoVisible(false);
                $('#presentation>iframe').fadeIn(300, function() {
                    $('#presentation>iframe').css({opacity:'1'});
                    dockToolbar(true);
                });
            });
        }
        else {
            if ($('#presentation>iframe').css('opacity') == '1') {
                $('#presentation>iframe').fadeOut(300, function () {
                    $('#presentation>iframe').css({opacity:'0'});
                    $('#reloadPresentation').css({display:'none'});
                    $('#largeVideo').fadeIn(300, function() {
                        setLargeVideoVisible(true);
                        dockToolbar(false);
                    });
                });
            }
        }
    };

    /**
     * Returns <tt>true</tt> if the presentation is visible, <tt>false</tt> -
     * otherwise.
     */
    my.isPresentationVisible = function () {
        return ($('#presentation>iframe') != null
                && $('#presentation>iframe').css('opacity') == 1);
    };

    /**
     * Opens the Prezi dialog, from which the user could choose a presentation
     * to load.
     */
    my.openPreziDialog = function() {
        var myprezi = connection.emuc.getPrezi(connection.emuc.myroomjid);
        if (myprezi) {
            $.prompt("Are you sure you would like to remove your Prezi?",
                    {
                    title: "Remove Prezi",
                    buttons: { "Remove": true, "Cancel": false},
                    defaultButton: 1,
                    submit: function(e,v,m,f){
                    if(v)
                    {
                        connection.emuc.removePreziFromPresence();
                        connection.emuc.sendPresence();
                    }
                }
            });
        }
        else if (preziPlayer != null) {
            $.prompt("Another participant is already sharing a Prezi." +
                    "This conference allows only one Prezi at a time.",
                     {
                     title: "Share a Prezi",
                     buttons: { "Ok": true},
                     defaultButton: 0,
                     submit: function(e,v,m,f){
                        $.prompt.close();
                     }
                     });
        }
        else {
            var openPreziState = {
            state0: {
                html:   '<h2>Share a Prezi</h2>' +
                        '<input id="preziUrl" type="text" ' +
                        'placeholder="e.g. ' +
                        'http://prezi.com/wz7vhjycl7e6/my-prezi" autofocus>',
                persistent: false,
                buttons: { "Share": true , "Cancel": false},
                defaultButton: 1,
                submit: function(e,v,m,f){
                    e.preventDefault();
                    if(v)
                    {
                        var preziUrl = document.getElementById('preziUrl');

                        if (preziUrl.value)
                        {
                            var urlValue
                                = encodeURI(Util.escapeHtml(preziUrl.value));

                            if (urlValue.indexOf('http://prezi.com/') != 0
                                && urlValue.indexOf('https://prezi.com/') != 0)
                            {
                                $.prompt.goToState('state1');
                                return false;
                            }
                            else {
                                var presIdTmp = urlValue.substring(
                                        urlValue.indexOf("prezi.com/") + 10);
                                if (!isAlphanumeric(presIdTmp)
                                        || presIdTmp.indexOf('/') < 2) {
                                    $.prompt.goToState('state1');
                                    return false;
                                }
                                else {
                                    connection.emuc
                                        .addPreziToPresence(urlValue, 0);
                                    connection.emuc.sendPresence();
                                    $.prompt.close();
                                }
                            }
                        }
                    }
                    else
                        $.prompt.close();
                }
            },
            state1: {
                html:   '<h2>Share a Prezi</h2>' +
                        'Please provide a correct prezi link.',
                persistent: false,
                buttons: { "Back": true, "Cancel": false },
                defaultButton: 1,
                submit:function(e,v,m,f) {
                    e.preventDefault();
                    if(v==0)
                        $.prompt.close();
                    else
                        $.prompt.goToState('state0');
                }
            }
            };

            var myPrompt = jQuery.prompt(openPreziState);

            myPrompt.on('impromptu:loaded', function(e) {
                        document.getElementById('preziUrl').focus();
                        });
            myPrompt.on('impromptu:statechanged', function(e) {
                        document.getElementById('preziUrl').focus();
                        });
        }
    };

    /**
     * A new presentation has been added.
     * 
     * @param event the event indicating the add of a presentation
     * @param jid the jid from which the presentation was added
     * @param presUrl url of the presentation
     * @param currentSlide the current slide to which we should move
     */
    var presentationAdded = function(event, jid, presUrl, currentSlide) {
        console.log("presentation added", presUrl);

        var presId = getPresentationId(presUrl);
        var elementId = 'participant_'
                        + Strophe.getResourceFromJid(jid)
                        + '_' + presId;

        addRemoteVideoContainer(elementId);
        resizeThumbnails();

        var controlsEnabled = false;
        if (jid === connection.emuc.myroomjid)
            controlsEnabled = true;

        Prezi.setPresentationVisible(true);
        $('#largeVideoContainer').hover(
            function (event) {
                if (Prezi.isPresentationVisible()) {
                    var reloadButtonRight = window.innerWidth
                        - $('#presentation>iframe').offset().left
                        - $('#presentation>iframe').width();

                    $('#reloadPresentation').css({  right: reloadButtonRight,
                                                    display:'inline-block'});
                }
            },
            function (event) {
                if (!Prezi.isPresentationVisible())
                    $('#reloadPresentation').css({display:'none'});
                else {
                    var e = event.toElement || event.relatedTarget;

                    if (e && e.id != 'reloadPresentation' && e.id != 'header')
                        $('#reloadPresentation').css({display:'none'});
                }
            });

        preziPlayer = new PreziPlayer(
                    'presentation',
                    {preziId: presId,
                    width: getPresentationWidth(),
                    height: getPresentationHeihgt(),
                    controls: controlsEnabled,
                    debug: true
                    });

        $('#presentation>iframe').attr('id', preziPlayer.options.preziId);

        preziPlayer.on(PreziPlayer.EVENT_STATUS, function(event) {
            console.log("prezi status", event.value);
            if (event.value == PreziPlayer.STATUS_CONTENT_READY) {
                if (jid != connection.emuc.myroomjid)
                    preziPlayer.flyToStep(currentSlide);
            }
        });

        preziPlayer.on(PreziPlayer.EVENT_CURRENT_STEP, function(event) {
            console.log("event value", event.value);
            connection.emuc.addCurrentSlideToPresence(event.value);
            connection.emuc.sendPresence();
        });

        $("#" + elementId).css( 'background-image',
                                'url(../images/avatarprezi.png)');
        $("#" + elementId).click(
            function () {
                Prezi.setPresentationVisible(true);
            }
        );
    };

    /**
     * A presentation has been removed.
     * 
     * @param event the event indicating the remove of a presentation
     * @param jid the jid for which the presentation was removed
     * @param the url of the presentation
     */
    var presentationRemoved = function (event, jid, presUrl) {
        console.log('presentation removed', presUrl);
        var presId = getPresentationId(presUrl);
        Prezi.setPresentationVisible(false);
        $('#participant_'
                + Strophe.getResourceFromJid(jid)
                + '_' + presId).remove();
        $('#presentation>iframe').remove();
        if (preziPlayer != null) {
            preziPlayer.destroy();
            preziPlayer = null;
        }
    };

    /**
     * Indicates if the given string is an alphanumeric string.
     * Note that some special characters are also allowed (-, _ , /, &, ?, =, ;) for the
     * purpose of checking URIs.
     */
    function isAlphanumeric(unsafeText) {
        var regex = /^[a-z0-9-_\/&\?=;]+$/i;
        return regex.test(unsafeText);
    }

    /**
     * Returns the presentation id from the given url.
     */
    function getPresentationId (presUrl) {
        var presIdTmp = presUrl.substring(presUrl.indexOf("prezi.com/") + 10);
        return presIdTmp.substring(0, presIdTmp.indexOf('/'));
    }

    /**
     * Returns the presentation width.
     */
    function getPresentationWidth() {
        var availableWidth = Util.getAvailableVideoWidth();
        var availableHeight = getPresentationHeihgt();

        var aspectRatio = 16.0 / 9.0;
        if (availableHeight < availableWidth / aspectRatio) {
            availableWidth = Math.floor(availableHeight * aspectRatio);
        }
        return availableWidth;
    }

    /**
     * Returns the presentation height.
     */
    function getPresentationHeihgt() {
        var remoteVideos = $('#remoteVideos');
        return window.innerHeight - remoteVideos.outerHeight();
    }

    /**
     * Resizes the presentation iframe.
     */
    function resize() {
        if ($('#presentation>iframe')) {
            $('#presentation>iframe').width(getPresentationWidth());
            $('#presentation>iframe').height(getPresentationHeihgt());
        }
    }

    /**
     * Presentation has been removed.
     */
    $(document).bind('presentationremoved.muc', presentationRemoved);

    /**
     * Presentation has been added.
     */
    $(document).bind('presentationadded.muc', presentationAdded);

    /*
     * Indicates presentation slide change.
     */
    $(document).bind('gotoslide.muc', function (event, jid, presUrl, current) {
        if (preziPlayer) {
            preziPlayer.flyToStep(current);
        }
    });

    /**
     * On video selected event.
     */
    $(document).bind('video.selected', function (event, isPresentation) {
        if (!isPresentation && $('#presentation>iframe'))
            Prezi.setPresentationVisible(false);
    });

    $(window).resize(function () {
        resize();
    });

    return my;
}(Prezi || {}));