var Doc = (function(){
    var Document = function(baseURL){
        this.pages = [];
        this.baseURL = baseURL;
    }
    
    Document.prototype.hasPage = function(index){
        return index >= 0 && index < this.pages.length;    
    }
    
    Document.prototype.getPageURL = function(pageNumber){
        var s = pageNumber <2 ? "" : "/" + pageNumber;
        return this.baseURL + s;
    }
    
    Document.prototype.page = function(index){
        return index + 1;
    }
    
    return Document;
})();

(function(){
    const PAGES = [];
    var currentPageIndex = 0;
    var doc = new Doc(location.pathname.replace(/\/\d+$/, ""));
    $(document).ready(function(){
        try{
            var hrefPage = /\/(\d+)$/.exec(location.href)[1];
            currentPageIndex = parseInt(hrefPage) - 1;
        }catch(error){

        }

        $("#buttonNext").click(function(event){
            loadNext();
        });

        $("#buttonPrev").click(function(event){
            loadPrevious();
        });
        
        $("#page-container .pf").each(function(index, elem){
            var url = $(elem).data("page-url");
            doc.pages.push(url);
        });
        
        $("#currentPage").attr("max", doc.pages.length);
        $("#totalPages").text(doc.pages.length);
        $("#currentPage").change(function(){
            var i = parseInt($(this).val()) - 1;
            if(i && doc.hasPage(i)){
                loadPage(i);
            }
        });
        
        $("#page-container").html("");   
        loadPage(currentPageIndex);

        window.addEventListener("popstate", function(event){
            console.log("pops");
            console.log(event);
            var i = event.state;
            loadPage(i);
        });
    });
    
    function loadNext(){
        var i = currentPageIndex + 1;
        if(doc.hasPage(i)){
            loadPage(i);
        }else{
            
        }
    }
    
    function loadPrevious(){
        var i = currentPageIndex - 1;
        if(doc.hasPage(i)){
            loadPage(i);
        }else{
            
        }
    }
    
    function loadPage(index){
        if(doc.hasPage(index)){
            var url = doc.pages[index];
            // $.ajax( 
            //     url,

            //     {
            //         xhrFields: {
            //             crossDomain: true,
            //             withCredentials: true
            //         },

            //         success: function(data, status){
            //             currentPageIndex = index;
            //             $("#currentPage").val(doc.page(currentPageIndex));
            //             $("#page-container").html(data);   

            //             var p = doc.page(currentPageIndex);
            //             console.log("look at page ", p);
            //             window.history.pushState(
            //                 currentPageIndex,
            //                 "State 2013 — " + p,
            //                 doc.getPageURL(p)
            //             ); 
            //         },

            //         error: function(xhr, aaa, error){
            //             console.log(error);
            //         }
            //     }
            // );
            $.get(url, function(data){
                currentPageIndex = index;
                $("#currentPage").val(doc.page(currentPageIndex));
                $("#page-container").html(data);   

                var p = doc.page(currentPageIndex);
                console.log("look at page ", p);
                window.history.pushState(
                    currentPageIndex,
                    "State 2013 — " + p,
                    doc.getPageURL(p)
                ); 
            });
        }
    }
})();