/*
 * classList.js: Cross-browser full element.classList implementation.
 * 1.1.20170427
 *
 * By Eli Grey, http://eligrey.com
 * License: Dedicated to the public domain.
 *   See https://github.com/eligrey/classList.js/blob/master/LICENSE.md
 */

/*global self, document, DOMException */

/*! @source http://purl.eligrey.com/github/classList.js/blob/master/classList.js */

if ('document' in window.self) {
  // Full polyfill for browsers with no classList support
  // Including IE < Edge missing SVGElement.classList
  if (
    !('classList' in document.createElement('_')) ||
    (document.createElementNS &&
      !('classList' in document.createElementNS('http://www.w3.org/2000/svg', 'g')))
  ) {
    (function (view) {
      'use strict';

      if (!('Element' in view)) return;

      var classListProp = 'classList',
        protoProp = 'prototype',
        elemCtrProto = view.Element[protoProp],
        objCtr = Object,
        strTrim =
          String[protoProp].trim ||
          function () {
            return this.replace(/^\s+|\s+$/g, '');
          },
        arrIndexOf =
          Array[protoProp].indexOf ||
          function (item) {
            var i = 0,
              len = this.length;
            for (; i < len; i++) {
              if (i in this && this[i] === item) {
                return i;
              }
            }
            return -1;
          },
        // Vendors: please allow content code to instantiate DOMExceptions
        DOMEx = function (type, message) {
          this.name = type;
          this.code = DOMException[type];
          this.message = message;
        },
        checkTokenAndGetIndex = function (classList, token) {
          if (token === '') {
            throw new DOMEx('SYNTAX_ERR', 'An invalid or illegal string was specified');
          }
          if (/\s/.test(token)) {
            throw new DOMEx('INVALID_CHARACTER_ERR', 'String contains an invalid character');
          }
          return arrIndexOf.call(classList, token);
        },
        ClassList = function (elem) {
          var trimmedClasses = strTrim.call(elem.getAttribute('class') || ''),
            classes = trimmedClasses ? trimmedClasses.split(/\s+/) : [],
            i = 0,
            len = classes.length;
          for (; i < len; i++) {
            this.push(classes[i]);
          }
          this._updateClassName = function () {
            elem.setAttribute('class', this.toString());
          };
        },
        classListProto = (ClassList[protoProp] = []),
        classListGetter = function () {
          return new ClassList(this);
        };
      // Most DOMException implementations don't allow calling DOMException's toString()
      // on non-DOMExceptions. Error's toString() is sufficient here.
      DOMEx[protoProp] = Error[protoProp];
      classListProto.item = function (i) {
        return this[i] || null;
      };
      classListProto.contains = function (token) {
        token += '';
        return checkTokenAndGetIndex(this, token) !== -1;
      };
      classListProto.add = function () {
        var tokens = arguments,
          i = 0,
          l = tokens.length,
          token,
          updated = false;
        do {
          token = tokens[i] + '';
          if (checkTokenAndGetIndex(this, token) === -1) {
            this.push(token);
            updated = true;
          }
        } while (++i < l);

        if (updated) {
          this._updateClassName();
        }
      };
      classListProto.remove = function () {
        var tokens = arguments,
          i = 0,
          l = tokens.length,
          token,
          updated = false,
          index;
        do {
          token = tokens[i] + '';
          index = checkTokenAndGetIndex(this, token);
          while (index !== -1) {
            this.splice(index, 1);
            updated = true;
            index = checkTokenAndGetIndex(this, token);
          }
        } while (++i < l);

        if (updated) {
          this._updateClassName();
        }
      };
      classListProto.toggle = function (token, force) {
        token += '';

        var result = this.contains(token),
          method = result ? force !== true && 'remove' : force !== false && 'add';
        if (method) {
          this[method](token);
        }

        if (force === true || force === false) {
          return force;
        } else {
          return !result;
        }
      };
      classListProto.toString = function () {
        return this.join(' ');
      };

      if (objCtr.defineProperty) {
        var classListPropDesc = {
          get: classListGetter,
          enumerable: true,
          configurable: true,
        };
        try {
          objCtr.defineProperty(elemCtrProto, classListProp, classListPropDesc);
        } catch (ex) {
          // IE 8 doesn't support enumerable:true
          // adding undefined to fight this issue https://github.com/eligrey/classList.js/issues/36
          // modernie IE8-MSW7 machine has IE8 8.0.6001.18702 and is affected
          if (ex.number === undefined || ex.number === -0x7ff5ec54) {
            classListPropDesc.enumerable = false;
            objCtr.defineProperty(elemCtrProto, classListProp, classListPropDesc);
          }
        }
      } else if (objCtr[protoProp].__defineGetter__) {
        elemCtrProto.__defineGetter__(classListProp, classListGetter);
      }
    })(window.self);
  }

  // There is full or partial native classList support, so just check if we need
  // to normalize the add/remove and toggle APIs.

  (function () {
    'use strict';

    var testElement = document.createElement('_');

    testElement.classList.add('c1', 'c2');

    // Polyfill for IE 10/11 and Firefox <26, where classList.add and
    // classList.remove exist but support only one argument at a time.
    if (!testElement.classList.contains('c2')) {
      var createMethod = function (method) {
        var original = DOMTokenList.prototype[method];

        DOMTokenList.prototype[method] = function (token) {
          var i,
            len = arguments.length;

          for (i = 0; i < len; i++) {
            token = arguments[i];
            original.call(this, token);
          }
        };
      };
      createMethod('add');
      createMethod('remove');
    }

    testElement.classList.toggle('c3', false);

    // Polyfill for IE 10 and Firefox <24, where classList.toggle does not
    // support the second argument.
    if (testElement.classList.contains('c3')) {
      var _toggle = DOMTokenList.prototype.toggle;

      DOMTokenList.prototype.toggle = function (token, force) {
        if (1 in arguments && !this.contains(token) === !force) {
          return force;
        } else {
          return _toggle.call(this, token);
        }
      };
    }

    testElement = null;
  })();
}
