load method

@override void load()

Loads the configuration data from the command line args.

Implementation

@override
void load() {
  var newData = LinkedHashMap<String, String>(
    equals: (a, b) => a.toLowerCase() == b.toLowerCase(),
    hashCode: (k) => k.toLowerCase().hashCode,
  );
  String? key;
  String? value;

  var enumerator = args.iterator;
  while (enumerator.moveNext()) {
    var currentArg = enumerator.current;
    var keyStartIndex = 0;

    if (currentArg.startsWith('--')) {
      keyStartIndex = 2;
    } else if (currentArg.startsWith('-')) {
      keyStartIndex = 1;
    } else if (currentArg.startsWith('/')) {
      // "/SomeSwitch" is equivalent to "--SomeSwitch" when interpreting switch mappings
      // So we do a conversion to simplify later processing
      currentArg = '--${currentArg.substring(1)}';
      keyStartIndex = 2;
    }

    var separator = currentArg.indexOf('=');
    if (separator < 0) {
      // If there is neither equal sign nor prefix in current
      // arugment, it is an invalid format
      if (keyStartIndex == 0) {
        // Ignore invalid formats
        continue;
      }
      // If the switch is a key in given switch mappings, interpret it
      if (_switchMappings != null) {
        if (_switchMappings!.containsKey(currentArg)) {
          key = _switchMappings![currentArg]!;
        } else if (keyStartIndex == 1) {
          continue;
        } else {
          key = currentArg.substring(keyStartIndex);
        }
      } else if (keyStartIndex == 1) {
        continue;
      } else {
        key = currentArg.substring(keyStartIndex);
      }

      // ignore: unused_local_variable
      var previousKey = enumerator.current;
      if (!enumerator.moveNext()) {
        // ignore missing values.
        continue;
      }
      value = enumerator.current;
    } else {
      var keySegment = currentArg.substring(0, separator);
      // If the switch is a key in given switch mappings, interpret it
      if (_switchMappings != null) {
        if (_switchMappings!.containsKey(keySegment)) {
          key = _switchMappings![keySegment]!;
          // If the switch starts with a single "-" and it
          // isn't in given mappings , it is an invalid usage
        } else if (keyStartIndex == 1) {
          throw Exception('''The short switch '$currentArg'
              is not defined in the switch mappings.''');
        } else {
          key = currentArg.substring(keyStartIndex, separator);
        }
        value = currentArg.substring(separator + 1);
      } else if (keyStartIndex == 1) {
        throw Exception('''The short switch '$currentArg' is
            not defined in the switch mappings.''');
      } else {
        key = currentArg.substring(keyStartIndex, separator);
      }

      value = currentArg.substring(separator + 1);
    }
    // Override value when key is duplicated.
    // So we always have the last argument win.
    newData[key] = value;
  }

  data = newData;
}