const { Command, Option } = require('../');

// Note: setting up shared command configuration in getSuggestion,
// and looking for possible subcommand 'sub'.

function getSuggestion(program, arg) {
  let message = '';
  program
    .showSuggestionAfterError() // make sure on
    .exitOverride()
    .configureOutput({
      writeErr: (str) => { message = str; }
    });
  // Do the same setup for subcommand.
  const sub = program._findCommand('sub');
  if (sub) sub.copyInheritedSettings(program);

  try {
    // Passing in an array for a few of the tests.
    const args = Array.isArray(arg) ? arg : [arg];
    program.parse(args, { from: 'user' });
  } catch (err) {
  }

  const match = message.match(/Did you mean (one of )?(.*)\?/);
  return match ? match[2] : null;
}

test.each([
  ['yyy', ['zzz'], null, 'none similar'],
  ['a', ['b'], null, 'one edit away but not similar'],
  ['a', ['ab'], 'ab', 'one edit away'],
  ['ab', ['a'], null, 'one edit away'],
  ['at', ['cat'], 'cat', '1 insertion'],
  ['cat', ['at'], 'at', '1 deletion'],
  ['bat', ['cat'], 'cat', '1 substitution'],
  ['act', ['cat'], 'cat', '1 transposition'],
  ['cxx', ['cat'], null, '2 edits away and short string'],
  ['caxx', ['cart'], 'cart', '2 edits away and longer string'],
  ['1234567', ['1234567890'], '1234567890', '3 edits away is similar for long string'],
  ['123456', ['1234567890'], null, '4 edits is too far'],
  ['xat', ['rat', 'cat', 'bat'], 'bat, cat, rat', 'sorted possibles'],
  ['cart', ['camb', 'cant', 'bard'], 'cant', 'only closest of different edit distances']
])('when cli of %s and commands %j then suggest %s because %s', (arg, commandNames, expected) => {
  const program = new Command();
  commandNames.forEach(name => { program.command(name); });
  const suggestion = getSuggestion(program, arg);
  expect(suggestion).toBe(expected);
});

test('when similar alias then suggest alias', () => {
  const program = new Command();
  program.command('xyz')
    .alias('car');
  const suggestion = getSuggestion(program, 'bar');
  expect(suggestion).toBe('car');
});

test('when similar hidden alias then not suggested', () => {
  const program = new Command();
  program.command('xyz')
    .alias('visible')
    .alias('silent');
  const suggestion = getSuggestion(program, 'slent');
  expect(suggestion).toBe(null);
});

test('when similar command and alias then suggest both', () => {
  const program = new Command();
  program.command('aaaaa')
    .alias('cat');
  program.command('bat');
  program.command('ccccc');
  const suggestion = getSuggestion(program, 'mat');
  expect(suggestion).toBe('bat, cat');
});

test('when implicit help command then help is candidate for suggestion', () => {
  const program = new Command();
  program.command('sub');
  const suggestion = getSuggestion(program, 'hepl');
  expect(suggestion).toBe('help');
});

test('when help command disabled then not candidate for suggestion', () => {
  const program = new Command();
  program.addHelpCommand(false);
  program.command('sub');
  const suggestion = getSuggestion(program, 'hepl');
  expect(suggestion).toBe(null);
});

test('when default help option then --help is candidate for suggestion', () => {
  const program = new Command();
  const suggestion = getSuggestion(program, '--hepl');
  expect(suggestion).toBe('--help');
});

test('when custom help option then --custom-help is candidate for suggestion', () => {
  const program = new Command();
  program.helpOption('-H, --custom-help');
  const suggestion = getSuggestion(program, '--custom-hepl');
  expect(suggestion).toBe('--custom-help');
});

test('when help option disabled then not candidate for suggestion', () => {
  const program = new Command();
  program.helpOption(false);
  const suggestion = getSuggestion(program, '--hepl');
  expect(suggestion).toBe(null);
});

test('when command:* listener and unknown command then no suggestion', () => {
  // Because one use for command:* was to handle unknown commands.
  // Listener actually stops error being thrown, but we just care about affect on suggestion in this test.
  const program = new Command();
  program.on('command:*', () => {});
  program.command('rat');
  const suggestion = getSuggestion(program, 'cat');
  expect(suggestion).toBe(null);
});

// Easy to just run same tests as for commands with cut and paste!
// Note: length calculations disregard the leading --
test.each([
  ['--yyy', ['--zzz'], null, 'none similar'],
  ['--a', ['--b'], null, 'one edit away but not similar'],
  ['--a', ['--ab'], '--ab', 'one edit away'],
  ['--ab', ['--a'], null, 'one edit away'],
  ['--at', ['--cat'], '--cat', '1 insertion'],
  ['--cat', ['--at'], '--at', '1 deletion'],
  ['--bat', ['--cat'], '--cat', '1 substitution'],
  ['--act', ['--cat'], '--cat', '1 transposition'],
  ['--cxx', ['--cat'], null, '2 edits away and short string'],
  ['--caxx', ['--cart'], '--cart', '2 edits away and longer string'],
  ['--1234567', ['--1234567890'], '--1234567890', '3 edits away is similar for long string'],
  ['--123456', ['--1234567890'], null, '4 edits is too far'],
  ['--xat', ['--rat', '--cat', '--bat'], '--bat, --cat, --rat', 'sorted possibles'],
  ['--cart', ['--camb', '--cant', '--bard'], '--cant', 'only closest of different edit distances']
])('when cli of %s and options %j then suggest %s because %s', (arg, commandNames, expected) => {
  const program = new Command();
  commandNames.forEach(name => { program.option(name); });
  const suggestion = getSuggestion(program, arg);
  expect(suggestion).toBe(expected);
});

test('when no options then no suggestion', () => {
  // Checking nothing blows up as much as no suggestion!
  const program = new Command();
  program
    .helpOption(false);
  const suggestion = getSuggestion(program, '--option');
  expect(suggestion).toBe(null);
});

test('when subcommand option then candidate for subcommand option suggestion', () => {
  const program = new Command();
  program.command('sub')
    .option('-l,--local');
  const suggestion = getSuggestion(program, ['sub', '--loca']);
  expect(suggestion).toBe('--local');
});

test('when global option then candidate for subcommand option suggestion', () => {
  const program = new Command();
  program.option('-g, --global');
  program.command('sub');
  const suggestion = getSuggestion(program, ['sub', '--globla']);
  expect(suggestion).toBe('--global');
});

test('when global option but positionalOptions then not candidate for subcommand suggestion', () => {
  const program = new Command();
  program
    .enablePositionalOptions();
  program.option('-g, --global');
  program.command('sub');
  const suggestion = getSuggestion(program, ['sub', '--globla']);
  expect(suggestion).toBe(null);
});

test('when global and local options then both candidates', () => {
  const program = new Command();
  program.option('--cat');
  program.command('sub')
    .option('--rat');
  const suggestion = getSuggestion(program, ['sub', '--bat']);
  expect(suggestion).toBe('--cat, --rat');
});

test('when command hidden then not suggested as candidate', () => {
  const program = new Command();
  program.command('secret', { hidden: true });
  const suggestion = getSuggestion(program, 'secrt');
  expect(suggestion).toBe(null);
});

test('when option hidden then not suggested as candidate', () => {
  const program = new Command();
  program.addOption(new Option('--secret').hideHelp());
  const suggestion = getSuggestion(program, '--secrt');
  expect(suggestion).toBe(null);
});

test('when may be duplicate identical candidates then only return one', () => {
  const program = new Command();
  program.command('sub');
  const suggestion = getSuggestion(program, ['sub', '--hepl']);
  expect(suggestion).toBe('--help');
});
