define([
	"../core",
	"../core/camelCase",
	"../var/rnothtmlwhite",
	"./var/acceptData"
], function (jQuery, camelCase, rnothtmlwhite, acceptData) {

	"use strict";

	function Data() {
		this.expando = jQuery.expando + Data.uid++;
	}

	Data.uid = 1;

	Data.prototype = {

		cache: function (owner) {

			// Check if the owner object already has a cache
			var value = owner[this.expando];

			// If not, create one
			if (!value) {
				value = {};

				// We can accept data for non-element nodes in modern browsers,
				// but we should not, see #8335.
				// Always return an empty object.
				if (acceptData(owner)) {

					// If it is a node unlikely to be stringify-ed or looped over
					// use plain assignment
					if (owner.nodeType) {
						owner[this.expando] = value;

						// Otherwise secure it in a non-enumerable property
						// configurable must be true to allow the property to be
						// deleted when data is removed
					} else {
						Object.defineProperty(owner, this.expando, {
							value: value,
							configurable: true
						});
					}
				}
			}

			return value;
		},
		set: function (owner, data, value) {
			var prop,
				cache = this.cache(owner);

			// Handle: [ owner, key, value ] args
			// Always use camelCase key (gh-2257)
			if (typeof data === "string") {
				cache[camelCase(data)] = value;

				// Handle: [ owner, { properties } ] args
			} else {

				// Copy the properties one-by-one to the cache object
				for (prop in data) {
					cache[camelCase(prop)] = data[prop];
				}
			}
			return cache;
		},
		get: function (owner, key) {
			return key === undefined ?
				this.cache(owner) :

				// Always use camelCase key (gh-2257)
				owner[this.expando] && owner[this.expando][camelCase(key)];
		},
		access: function (owner, key, value) {

			// In cases where either:
			//
			//   1. No key was specified
			//   2. A string key was specified, but no value provided
			//
			// Take the "read" path and allow the get method to determine
			// which value to return, respectively either:
			//
			//   1. The entire cache object
			//   2. The data stored at the key
			//
			if (key === undefined ||
				((key && typeof key === "string") && value === undefined)) {

				return this.get(owner, key);
			}

			// When the key is not a string, or both a key and value
			// are specified, set or extend (existing objects) with either:
			//
			//   1. An object of properties
			//   2. A key and value
			//
			this.set(owner, key, value);

			// Since the "set" path can have two possible entry points
			// return the expected data based on which path was taken[*]
			return value !== undefined ? value : key;
		},
		remove: function (owner, key) {
			var i,
				cache = owner[this.expando];

			if (cache === undefined) {
				return;
			}

			if (key !== undefined) {

				// Support array or space separated string of keys
				if (Array.isArray(key)) {

					// If key is an array of keys...
					// We always set camelCase keys, so remove that.
					key = key.map(camelCase);
				} else {
					key = camelCase(key);

					// If a key with the spaces exists, use it.
					// Otherwise, create an array by matching non-whitespace
					key = key in cache ?
						[key] :
						(key.match(rnothtmlwhite) || []);
				}

				i = key.length;

				while (i--) {
					delete cache[key[i]];
				}
			}

			// Remove the expando if there's no more data
			if (key === undefined || jQuery.isEmptyObject(cache)) {

				// Support: Chrome <=35 - 45
				// Webkit & Blink performance suffers when deleting properties
				// from DOM nodes, so set to undefined instead
				// https://bugs.chromium.org/p/chromium/issues/detail?id=378607 (bug restricted)
				if (owner.nodeType) {
					owner[this.expando] = undefined;
				} else {
					delete owner[this.expando];
				}
			}
		},
		hasData: function (owner) {
			var cache = owner[this.expando];
			return cache !== undefined && !jQuery.isEmptyObject(cache);
		}
	};

	return Data;
});
