/**
   * @fileoverview Rule to require parens in arrow function arguments.
   * @author Jxck
   * @copyright 2015 Jxck. All rights reserved.
   */
  "use strict";
  
  //------------------------------------------------------------------------------
  // Rule Definition
  //------------------------------------------------------------------------------
  
  module.exports = function(context) {
      var message = "Expected parentheses around arrow function argument.";
      var asNeededMessage = "Unexpected parentheses around single function argument";
      var asNeeded = context.options[0] === "as-needed";
  
      /**
       * Determines whether a arrow function argument end with `)`
       * @param {ASTNode} node The arrow function node.
       * @returns {void}
       */
      function parens(node) {
          var token = context.getFirstToken(node);
  
          // as-needed: x => x
          if (asNeeded && node.params.length === 1 && node.params[0].type === "Identifier") {
              if (token.type === "Punctuator" && token.value === "(") {
                  context.report(node, asNeededMessage);
              }
              return;
          }
  
          if (token.type === "Identifier") {
              var after = context.getTokenAfter(token);
  
              // (x) => x
              if (after.value !== ")") {
                  context.report(node, message);
              }
          }
      }
  
      return {
          "ArrowFunctionExpression": parens
      };
  };
  
  module.exports.schema = [
      {
          "enum": ["always", "as-needed"]
      }
  ];