var Playlist = function(instance, playlist, options) {
    var self = this;

    this.instance = instance; // String: To associate specific HTML with this playlist
    this.playlist = playlist; // Array of Objects: The playlist
    this.options = options; // Object: The jPlayer constructor options for this playlist

    this.current = 0;

    this.cssId = {
        jPlayer: "jquery_jplayer_",
        interface: "jp_interface_",
        playlist: "jp_playlist_"
    };
    this.cssSelector = {};

    $.each(this.cssId, function(entity, id) {
        self.cssSelector[entity] = "#" + id + self.instance;
    });

    if(!this.options.cssSelectorAncestor) {
        this.options.cssSelectorAncestor = this.cssSelector.interface;
    }

    $(this.cssSelector.jPlayer).jPlayer(this.options);

    $(this.cssSelector.interface + " .jp-previous").click(function() {
        self.playlistPrev();
        $(this).blur();
        return false;
    });

    $(this.cssSelector.interface + " .jp-next").click(function() {
        self.playlistNext();
        $(this).blur();
        return false;
    });
};

Playlist.prototype = {
    displayPlaylist: function() {
        var self = this;
        $(this.cssSelector.playlist + " ul").empty();
        for (i=0; i < this.playlist.length; i++) {
            var listItem = (i === this.playlist.length-1) ? "<li class='jp-playlist-last'>" : "<li>";
            listItem += "<a href='#' id='" + this.cssId.playlist + this.instance + "_item_" + i +"' tabindex='1'>"+ this.playlist[i].name +"</a>";

            // Create links to free media
            if(this.playlist[i].free) {
                var first = true;
                listItem += "<div class='jp-free-media'>(";
                $.each(this.playlist[i], function(property,value) {
                    if($.jPlayer.prototype.format[property]) { // Check property is a media format.
                        if(first) {
                            first = false;
                        } else {
                            listItem += " | ";
                        }
                        listItem += "<a id='" + self.cssId.playlist + self.instance + "_item_" + i + "_" + property + "' href='" + value + "' tabindex='1'>" + property + "</a>";
                    }
                });
                listItem += ")</span>";
            }

            listItem += "</li>";

            // Associate playlist items with their media
            $(this.cssSelector.playlist + " ul").append(listItem);
            $(this.cssSelector.playlist + "_item_" + i).data("index", i).click(function() {
                var index = $(this).data("index");
                if(self.current !== index) {
                    self.playlistChange(index);
                } else {
                    $(self.cssSelector.jPlayer).jPlayer("play");
                }
                $(this).blur();
                return false;
            });

            // Disable free media links to force access via right click
            if(this.playlist[i].free) {
                $.each(this.playlist[i], function(property,value) {
                    if($.jPlayer.prototype.format[property]) { // Check property is a media format.
                        $(self.cssSelector.playlist + "_item_" + i + "_" + property).data("index", i).click(function() {
                            var index = $(this).data("index");
                            $(self.cssSelector.playlist + "_item_" + index).click();
                            $(this).blur();
                            return false;
                        });
                    }
                });
            }
        }
    },
    playlistInit: function(autoplay) {
        if(autoplay) {
            this.playlistChange(this.current);
        } else {
            this.playlistConfig(this.current);
        }
    },
    playlistConfig: function(index) {
        $(this.cssSelector.playlist + "_item_" + this.current).removeClass("jp-playlist-current").parent().removeClass("jp-playlist-current");
        $(this.cssSelector.playlist + "_item_" + index).addClass("jp-playlist-current").parent().addClass("jp-playlist-current");
        this.current = index;
        $(this.cssSelector.jPlayer).jPlayer("setMedia", this.playlist[this.current]);
    },
    playlistChange: function(index) {
        this.playlistConfig(index);
        $(this.cssSelector.jPlayer).jPlayer("play");
    },
    playlistNext: function() {
        var index = (this.current + 1 < this.playlist.length) ? this.current + 1 : 0;
        this.playlistChange(index);
    },
    playlistPrev: function() {
        var index = (this.current - 1 >= 0) ? this.current - 1 : this.playlist.length - 1;
        this.playlistChange(index);
    }
};