"use strict";

const hasBlock = require("../../utils/hasBlock");
const rawNodeString = require("../../utils/rawNodeString");
const report = require("../../utils/report");
const ruleMessages = require("../../utils/ruleMessages");
const validateOptions = require("../../utils/validateOptions");
const whitespaceChecker = require("../../utils/whitespaceChecker");

const ruleName = "at-rule-semicolon-space-before";

const messages = ruleMessages(ruleName, {
  expectedBefore: () => 'Expected single space before ";"',
  rejectedBefore: () => 'Unexpected whitespace before ";"'
});

const rule = function(expectation) {
  const checker = whitespaceChecker("space", expectation, messages);

  return (root, result) => {
    const validOptions = validateOptions(result, ruleName, {
      actual: expectation,
      possible: ["always", "never"]
    });
    if (!validOptions) {
      return;
    }

    root.walkAtRules(atRule => {
      if (hasBlock(atRule)) {
        return;
      }
      const nodeString = rawNodeString(atRule);

      checker.before({
        source: nodeString,
        index: nodeString.length,
        err: m => {
          report({
            message: m,
            node: atRule,
            index: nodeString.length - 1,
            result,
            ruleName
          });
        }
      });
    });
  };
};

rule.ruleName = ruleName;
rule.messages = messages;
module.exports = rule;