gistfile1.txt

$(function(){
    var raw_data;
    var positions = [];
    $('#wiki-body').each(function(){
        var txt = $(this).html();
        var checkbox = '<input class="task-list" type="checkbox" '
        $(this).html(
            txt.replace(/\[x\]/g, checkbox + 'checked>').
                replace(/\[ \]/g, checkbox + '>')
        );
    });
    var task_list = $('input.task-list');
    task_list.each(function(i){
        if ($(this).parent()[0].nodeName != "LABEL"){
            $(this).parent().contents().wrapAll("<label></label>");
        }
        $(this).attr({index: i})
    });
    // $(document).off("change", 'input.task-list[type=checkbox]');
    function change(){
        var i = $(this).attr("index");
        var state = ($(this).attr("checked") == "checked")? "[x]": "[ ]";
        var path = location.pathname.split("/");
        path.shift();
        //$.get("/data" + location.pathname).done(function(data){
        $.ajax({url: "/data" + location.pathname,
                cache: false,
                type: "GET"
               }).done(function(data){
            var checkbox_re=/\[ \]|\[x\]/g;
            var result;
            while ((result = checkbox_re.exec(data)) !== null) {
                positions.push([result.index, checkbox_re.lastIndex]);
            }
            raw_data = data;
            $.post("/edit" + location.pathname,
                   { page: path.pop(),
                     path: path.join("/"),
                     format: "markdown",
                     content: raw_data.slice(0, positions[i][0]) +
                     state + raw_data.slice(positions[i][1]),
                     message: "Updated "
                   })
        });
    }
    $(document).on("change", 'input.task-list[type=checkbox]', change);
});