"use strict";

const _ = require("lodash");
const blockString = require("../../utils/blockString");
const hasBlock = require("../../utils/hasBlock");
const optionsMatches = require("../../utils/optionsMatches");
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 = "block-closing-brace-newline-after";

const messages = ruleMessages(ruleName, {
  expectedAfter: () => 'Expected newline after "}"',
  expectedAfterSingleLine: () =>
    'Expected newline after "}" of a single-line block',
  rejectedAfterSingleLine: () =>
    'Unexpected whitespace after "}" of a single-line block',
  expectedAfterMultiLine: () =>
    'Expected newline after "}" of a multi-line block',
  rejectedAfterMultiLine: () =>
    'Unexpected whitespace after "}" of a multi-line block'
});

const rule = function(expectation, options) {
  const checker = whitespaceChecker("newline", expectation, messages);
  return (root, result) => {
    const validOptions = validateOptions(
      result,
      ruleName,
      {
        actual: expectation,
        possible: [
          "always",
          "always-single-line",
          "never-single-line",
          "always-multi-line",
          "never-multi-line"
        ]
      },
      {
        actual: options,
        possible: {
          ignoreAtRules: [_.isString]
        },
        optional: true
      }
    );
    if (!validOptions) {
      return;
    }

    // Check both kinds of statements: rules and at-rules
    root.walkRules(check);
    root.walkAtRules(check);

    function check(statement) {
      if (!hasBlock(statement)) {
        return;
      }
      if (optionsMatches(options, "ignoreAtRules", statement.name)) {
        return;
      }

      const nextNode = statement.next();
      if (!nextNode) {
        return;
      }

      // Allow an end-of-line comment x spaces after the brace
      const nextNodeIsSingleLineComment =
        nextNode.type === "comment" &&
        !/[^ ]/.test(nextNode.raws.before || "") &&
        nextNode.toString().indexOf("\n") === -1;

      const nodeToCheck = nextNodeIsSingleLineComment
        ? nextNode.next()
        : nextNode;

      if (!nodeToCheck) {
        return;
      }

      let reportIndex = statement.toString().length;
      let source = rawNodeString(nodeToCheck);

      // Skip a semicolon at the beginning, if any
      if (source && source[0] === ";") {
        source = source.slice(1);
        reportIndex++;
      }

      // Only check one after, because there might be other
      // spaces handled by the indentation rule
      checker.afterOneOnly({
        source,
        index: -1,
        lineCheckStr: blockString(statement),
        err: msg => {
          report({
            message: msg,
            node: statement,
            index: reportIndex,
            result,
            ruleName
          });
        }
      });
    }
  };
};

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