import 'dart:convert';
import 'package:convert/convert.dart';
import 'package:crypto/crypto.dart';

void main() {
  // This tests whether a pattern matches a string.
  final match = RegExp(r'p([a-z]+)ch').hasMatch('peach');
  print(match);

  // For other regex tasks, you'll need to create a RegExp object.
  final r = RegExp(r'p([a-z]+)ch');

  // Many methods are available on these objects. Here's
  // a match test like we saw earlier.
  print(r.hasMatch('peach'));

  // This finds the match for the regex.
  print(r.stringMatch('peach punch'));

  // This finds the first match but returns the
  // start and end indexes for the match instead of the
  // matching text.
  final match2 = r.firstMatch('peach punch');
  print('idx: [${match2?.start}, ${match2?.end}]');

  // The groups in the regex pattern can be accessed
  // using the groups method on the match object.
  final match3 = r.firstMatch('peach punch');
  print(match3?.groups([0, 1]));

  // To find all matches in the input, use allMatches.
  final allMatches = r.allMatches('peach punch pinch');
  print(allMatches.map((m) => m.group(0)).toList());

  // Providing a non-negative integer as the second
  // argument to these functions will limit the number
  // of matches.
  final limitedMatches = r.allMatches('peach punch pinch').take(2);
  print(limitedMatches.map((m) => m.group(0)).toList());

  // Our examples above had string arguments. We can also provide
  // List<int> arguments (which is equivalent to []byte in Go).
  final utf8Encoder = Utf8Encoder();
  print(r.hasMatch(String.fromCharCodes(utf8Encoder.convert('peach'))));

  // The RegExp package can also be used to replace
  // subsets of strings with other values.
  print(r.stringMatch('a peach')?.replaceAll(r, '<fruit>'));

  // The replaceAllMapped variant allows you to transform matched
  // text with a given function.
  final input = utf8Encoder.convert('a peach');
  final output = r.allMatches(String.fromCharCodes(input))
      .map((match) => match.group(0)?.toUpperCase())
      .join();
  print(output);
}