// Copyright 2014 The Flutter Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

import 'package:path/path.dart' as path;

import 'base_code_gen.dart';
import 'logical_key_data.dart';
import 'physical_key_data.dart';
import 'utils.dart';

String _toUpperSnake(String lowerCamel) {
  // Converts 'myTVFoo' to 'myTvFoo'.
  final String trueUpperCamel = lowerCamel.replaceAllMapped(
    RegExp(r'([A-Z]{3,})'),
    (Match match) {
      final String matched = match.group(1)!;
      return matched.substring(0, 1)
           + matched.substring(1, matched.length - 2).toLowerCase()
           + matched.substring(matched.length - 2, matched.length - 1);
    });
  // Converts 'myTvFoo' to 'MY_TV_FOO'.
  return trueUpperCamel.replaceAllMapped(
    RegExp(r'([A-Z])'),
    (Match match) => '_${match.group(1)!}').toUpperCase();
}

/// Generates the common/testing/key_codes.h based on the information in the key
/// data structure given to it.
class KeyCodesJavaGenerator extends BaseCodeGenerator {
  KeyCodesJavaGenerator(super.keyData, super.logicalData);

  /// Gets the generated definitions of PhysicalKeyboardKeys.
  String get _physicalDefinitions {
    final OutputLines<int> lines = OutputLines<int>('Physical Key list');
    for (final PhysicalKeyEntry entry in keyData.entries) {
      lines.add(entry.usbHidCode, '''
  public static final long PHYSICAL_${_toUpperSnake(entry.constantName)} = ${toHex(entry.usbHidCode)}L;''');
    }
    return lines.sortedJoin().trimRight();
  }

  /// Gets the generated definitions of PhysicalKeyboardKeys.
  String get _logicalDefinitions {
    final OutputLines<int> lines = OutputLines<int>('Logical Key list', behavior: DeduplicateBehavior.kSkip);
    for (final LogicalKeyEntry entry in logicalData.entries) {
      lines.add(entry.value, '''
  public static final long LOGICAL_${_toUpperSnake(entry.constantName)} = ${toHex(entry.value, digits: 11)}L;''');
    }
    return lines.sortedJoin().trimRight();
  }

  @override
  String get templatePath => path.join(dataRoot, 'key_codes_java.tmpl');

  @override
  Map<String, String> mappings() {
    return <String, String>{
      'LOGICAL_KEY_DEFINITIONS': _logicalDefinitions,
      'PHYSICAL_KEY_DEFINITIONS': _physicalDefinitions,
    };
  }
}