/**
   * @fileoverview Rule to check multiple var declarations per line
   * @author Alberto Rodríguez
   */
  "use strict";
  
  //------------------------------------------------------------------------------
  // Rule Definition
  //------------------------------------------------------------------------------
  
  module.exports = {
      meta: {
          docs: {
              description: "require or disallow newlines around variable declarations",
              category: "Stylistic Issues",
              recommended: false
          },
  
          schema: [
              {
                  enum: ["always", "initializations"]
              }
          ],
  
          fixable: "whitespace"
      },
  
      create(context) {
  
          const ERROR_MESSAGE = "Expected variable declaration to be on a new line.";
          const always = context.options[0] === "always";
  
          //--------------------------------------------------------------------------
          // Helpers
          //--------------------------------------------------------------------------
  
  
          /**
           * Determine if provided keyword is a variant of for specifiers
           * @private
           * @param {string} keyword - keyword to test
           * @returns {boolean} True if `keyword` is a variant of for specifier
           */
          function isForTypeSpecifier(keyword) {
              return keyword === "ForStatement" || keyword === "ForInStatement" || keyword === "ForOfStatement";
          }
  
          /**
           * Checks newlines around variable declarations.
           * @private
           * @param {ASTNode} node - `VariableDeclaration` node to test
           * @returns {void}
           */
          function checkForNewLine(node) {
              if (isForTypeSpecifier(node.parent.type)) {
                  return;
              }
  
              const declarations = node.declarations;
              let prev;
  
              declarations.forEach(current => {
                  if (prev && prev.loc.end.line === current.loc.start.line) {
                      if (always || prev.init || current.init) {
                          context.report({
                              node,
                              message: ERROR_MESSAGE,
                              loc: current.loc.start,
                              fix: fixer => fixer.insertTextBefore(current, "
  ")
                          });
                      }
                  }
                  prev = current;
              });
          }
  
          //--------------------------------------------------------------------------
          // Public
          //--------------------------------------------------------------------------
  
          return {
              VariableDeclaration: checkForNewLine
          };
  
      }
  };