/// jquery.dataset v0.1.0 -- HTML5 dataset jQuery plugin
/// http://orangesoda.net/jquery.dataset.html

/// Copyright (c) 2009, Ben Weaver.  All rights reserved.
/// This software is issued "as is" under a BSD license
/// <http://orangesoda.net/license.html>.  All warrenties disclaimed.

///  The HTML5 specification allows elements to have custom data
///  attributes that are prefixed with `data-'.  They may be
///  conveniently accessed through an element's `dataset' property.
///  This plugin provides similar functionality.
///
///  The methods in the plugin are designed to be similar to the
///  built-in `attr' and `data' methods.  All names are without the
///  `data-' prefix.
//
///  These methods are defined:
///
///    dataset()
///      Return an object with all custom attribute (name, value) items.
///
///    dataset(name)
///      Return the value of the attribute `data-NAME'.
///
///    dataset(name, value)
///      Set the value of attribtue `data-NAME' to VALUE.
///
///    dataset({...})
///      Set many custom attributes at once.
///
///    removeDataset(name)
///      Remove the attribute `data-NAME'.
///
///    removeDataset([n1, n2, ...])
///      Remove the attributes `data-N1', `data-N2', ...

(function($) {
     var PREFIX = 'data-',
   PATTERN = /^data\-(.*)$/;

     function dataset(name, value) {
   if (value !== undefined) {
       // dataset(name, value): set the NAME attribute to VALUE.
       return this.attr(PREFIX + name, value);
   }

   switch (typeof name) {
   case 'string':
       // dataset(name): get the value of the NAME attribute.
       return this.attr(PREFIX + name);

   case 'object':
       // dataset(items): set the values of all (name, value) items.
       return set_items.call(this, name);

   case 'undefined':
       // dataset(): return a mapping of (name, value) items for the
       // first element.
       return get_items.call(this);

   default:
       throw 'dataset: invalid argument ' + name;
   }
     }

     function get_items() {
   return this.foldAttr(function(index, attr, result) {
       var match = PATTERN.exec(this.name);
       if (match) result[match[1]] = this.value;
   });
     }

     function set_items(items) {
   for (var key in items) {
       this.attr(PREFIX + key, items[key]);
   }
   return this;
     }

     function remove(name) {
   if (typeof name == 'string') {
       // Remove a single attribute;
       return this.removeAttr(PREFIX + name);
   }
   return remove_names(name);
     }

     function remove_names(obj) {
   var idx, length = obj && obj.length;

   // For any object, remove attributes named by the keys.
   if (length === undefined) {
       for (idx in obj) {
     this.removeAttr(PREFIX + idx);
       }
   }
   // For an array, remove attributes named by the values.
   else {
       for (idx = 0; idx < length; idx++) {
     this.removeAttr(PREFIX + obj[idx]);
       }
   }

   return this;
     }

     $.fn.dataset = dataset;
     $.fn.removeDataset = remove_names;

})(jQuery);

(function($) {

     function each_attr(proc) {
   if (this.length > 0) {
       $.each(this[0].attributes, proc);
   }
   return this;
     }

     function fold_attr(proc, acc) {
   return fold((this.length > 0) && this[0].attributes, proc, acc);
     }

     /*
      * A left-fold operator. The behavior is the same as $.each(),
      * but the callback is called with the accumulator as the third
      * argument.  The default accumulator is an empty object.
      */
     function fold(object, proc, acc) {
   var length = object && object.length;

   // The default accumulator is an empty object.
   if (acc === undefined) acc = {};

   // Returning an empty accumulator when OBJECT is "false"
   // makes FOLD more composable.
   if (!object) return acc;

   // Check to see if OBJECT is an array.
   if (length !== undefined) {
       for (var i = 0, value = object[i];
      (i < length) && (proc.call(value, i, value, acc) !== false);
      value = object[++i])
       { }
   }
   // Object is a map of (name, value) items.
   else {
       for (var name in object) {
     if (proc.call(object[name], name, object[name], acc) === false) break;
       }
   }

   return acc;
     }

     function fold_jquery(proc, acc) {
   if (acc === undefined) acc = [];
   return fold(this, proc, acc);
     }

     $.fn.eachAttr = each_attr;
     $.fn.foldAttr = fold_attr;
     $.fn.fold = fold_jquery;
     $.fold = fold;

})(jQuery);