// @flow

const os = require('os');
const chalk = require('chalk');
const stripAnsi = require('strip-ansi');
const table = require('text-table');

function pluralize(word, count) {
  return count === 1 ? word : `${word}s`;
}



type Results = $ReadOnlyArray<{|
  +messages: $ReadOnlyArray<{|
    +fatal: boolean,
    +severity: number,
    +line: number,
    +column: number,
    +message: string,
    +ruleId: string, |}>,

  +errorCount: number,
  +warningCount: number,
  +fixableErrorCount: number,
  +fixableWarningCount: number, |}>;




module.exports = function (results: Results) {
  let output = os.EOL;
  let errorCount = 0;
  let warningCount = 0;
  let fixableErrorCount = 0;
  let fixableWarningCount = 0;
  let summaryColor = 'yellow';

  results.forEach(result => {
    const messages = result.messages;

    if (messages.length === 0) {
      return;
    }

    errorCount += result.errorCount;
    warningCount += result.warningCount;
    fixableErrorCount += result.fixableErrorCount;
    fixableWarningCount += result.fixableWarningCount;

    output +=
    table(
    messages.map(message => {
      let messageType;
      if (message.fatal || message.severity === 2) {
        messageType = chalk.red('error');
        summaryColor = 'red';
      } else {
        messageType = chalk.yellow('warning');
      }
      return [
      '',
      message.line || 0,
      message.column || 0,
      messageType,
      message.message.replace(/(?<msg>[^ ])\.$/, '$1'),
      chalk.dim(message.ruleId || '')];

    }),
    {
      align: ['', 'r', 'l'],
      stringLength(str) {
        return stripAnsi(str).length;
      } }).


    split(os.EOL).
    map((el) =>
    el.replace(/(?<line>\d+)\s+(?<column>\d+)/, (m, p1, p2) => chalk.dim(`${p1}:${p2}`))).

    join(os.EOL) + os.EOL;
  });

  const total = errorCount + warningCount;

  if (total > 0) {
    if (fixableErrorCount > 0 || fixableWarningCount > 0) {
      output +=
      os.EOL +
      // $FlowExpectedError: indexer property is missing in Chalk (problem of Chalk)
      chalk[summaryColor].bold(
      [
      '  ',
      fixableErrorCount,
      pluralize(' error', fixableErrorCount),
      ' and ',
      fixableWarningCount,
      pluralize(' warning', fixableWarningCount),
      ' potentially fixable with the `--fix` option.\n'].
      join(''));

    }
  }

  return total > 0 ? output : '';
};