feat: command to generate config file template

bin/generate.dart

@@ -0,0 +1,97 @@
+import 'dart:io';
+
+import 'package:args/args.dart';
+
+import 'package:flutter_launcher_icons/constants.dart';
+import 'package:flutter_launcher_icons/src/version.dart';
+
+/// The function will be called from command line
+/// using the following command:
+/// ```sh
+/// flutter pub run flutter_launcher_icons:generate
+/// ```
+///
+/// Calling this function will generate a flutter_launcher_icons.yaml file
+/// with a default config template.
+///
+/// This command can take 2 optional arguments:
+/// - --override: This will override the current `flutter_launcher_icons.yaml`
+/// file if it exists, if not provided, the file will not be overridden and
+/// a message will be printed to the console.
+///
+/// - --fileName: This flag will take a file name as an argument and
+/// will generate the config format in that file instead of the default
+/// `flutter_launcher_icons.yaml` file, if not provided,
+/// the default file will be used.
+void main(List<String> arguments) {
+  print(introMessage(packageVersion));
+
+  final parser = ArgParser()
+    ..addFlag('override', abbr: 'o', defaultsTo: false)
+    ..addOption(
+      'fileName',
+      abbr: 'f',
+      defaultsTo: './flutter_launcher_icons.yaml',
+    );
+
+  final results = parser.parse(arguments);
+  final override = results['override'] as bool;
+  final fileName = results['fileName'] as String;
+
+  // Check if fileName is valid and has a .yaml extension
+  if (!fileName.endsWith('.yaml')) {
+    print('Invalid file name, please provide a valid file name');
+    return;
+  }
+
+  final file = File(fileName);
+  if (file.existsSync()) {
+    if (override) {
+      print('File already exists, overriding...');
+      _generateConfigFile(file);
+    } else {
+      print(
+        'File already exists, use --override flag to override the file, or use --fileName flag to use a different file name',
+      );
+    }
+  } else {
+    file.createSync(recursive: true);
+    _generateConfigFile(file);
+  }
+}
+
+void _generateConfigFile(File configFile) {
+  configFile.writeAsStringSync(_configFileTemplate);
+  print('Config file generated successfully');
+}
+
+const _configFileTemplate = '''
+# flutter pub run flutter_launcher_icons
+flutter_icons:
+  image_path: "assets/icon/icon.png"
+
+  android: "launcher_icon"
+  # image_path_android: "assets/icon/icon.png"
+  min_sdk_android: 21 # android min sdk min:16, default 21
+  # adaptive_icon_background: "assets/icon/background.png"
+  # adaptive_icon_foreground: "assets/icon/foreground.png"
+
+  ios: true
+  # image_path_ios: "assets/icon/icon.png"
+  remove_alpha_channel_ios: true
+
+  web:
+    generate: true
+    image_path: "path/to/image.png"
+    background_color: "#hexcode"
+    theme_color: "#hexcode"
+
+  windows:
+    generate: true
+    image_path: "path/to/image.png"
+    icon_size: 48 # min:48, max:256, default: 48
+
+  macos:
+    generate: true
+    image_path: "path/to/image.png"
+''';