// Copyright (C) 2012 Eric Schulte <schulte.eric@gmail.com>
// License GPLV3

// after the page loads, run the set set_clickable function
$(document).ready( function(){ set_clickable(); } );

function set_clickable(){
  // add edit button to every element with class="edit_in_place"
  $('.edit_button').remove();
  $('.edit_in_place')
    .before('<input type="button" value="EDIT" class="edit_button">');
  $('.edit_button').click(function(){
    var main = $(this).next();
    var org  = main.next().html();
    var beg  = main.next().attr("contents-begin");
    var end  = main.next().attr("contents-end");
    var html = main.html();
    main.after(
      '<div><textarea rows="10" cols="80">'+org+'</textarea><div>'+
        '<input type="button" value="SAVE" class="save_button" />'+
        '<input type="button" value="CANCEL" class="cancel_button" />'+
        '</div></div>');
    // remove the orignal html
    $(this).remove(); main.remove();
    // call these functions when buttons are hit
    $('.save_button').click(function(){
      save_changes(this, $(this).parent().prev().val(), beg, end);
    });
    $('.cancel_button').click(function(){ abort_changes(this, html); });
  });
  // TODO: show edit button on mousover
  $('.edit_in_place').hover(function(){ $(this).prev().show(); },
                            function(){ $(this).prev().hide(); } );
  $('.edit_button').hover(function(){ $(this).show(); },
                          function(){ $(this).hide(); } );
};

function save_changes(obj, org, beg, end){
  var here = window.location.pathname;
  $.ajax({
    type: 'POST',
    url: here,
    data: {org:  org,
           beg:  beg,
           end:  end,
           path: here},
    statusCode: {
      200: function(html,status){
        $(obj).parent().parent().next().after(
          '<div class="edit_in_place">'+html+'</div>'+
            '<div class="raw-org" contents-begin="'+beg+
            '" contents-end="'+end+'">'+org+'</div>');
        if(typeof(MathJax) !== 'undefined') {
          MathJax.Hub.Queue(["Typeset", MathJax.Hub,
                             $(obj).parent().parent().next().next().get()]);
        }
        $(obj).parent().parent().next().remove();
        $(obj).parent().parent().remove();
        update_offsets(end, (org.length - (Number(end) - Number(beg))));
        set_clickable();
      },
      403: function(){ alert("Unauthorized"); },
      500: function(error){ alert('error:'+error); }
    }
  });
};

function abort_changes(obj, old_html){
  $(obj).parent().parent().after(
    '<div class="edit_in_place">'+old_html+'</div>');
  $(obj).parent().parent().remove();
  set_clickable();
};

function update_offsets(end, delta){
  $('.raw-org').map(function(){
    var old_beg = Number($(this).attr('contents-begin'));
    if(old_beg >= end) { $(this).attr('contents-begin', (old_beg + delta)); }
    var old_end = Number($(this).attr('contents-end'));
    if(old_end >= end) { $(this).attr('contents-end', (old_end + delta)); }
  });
};