addStringToMap static method

void addStringToMap({ required Map<String, dynamic> map, required String destinationPath, required String leafContent, })

Adds a string (leaf) to the map at the specified path

Implementation

static void addStringToMap({
  required Map<String, dynamic> map,
  required String destinationPath,
  required String leafContent,
}) {
  final pathList = destinationPath.split('.');

  // starts with type Map<String, dynamic> but
  // may be a Map<String, dynamic> or List<dynamic> after the 1st iteration
  dynamic curr = map;

  for (int i = 0; i < pathList.length; i++) {
    final subPath = pathList[i];
    final subPathInt = int.tryParse(subPath);

    final nextSubPath = i + 1 < pathList.length ? pathList[i + 1] : null;
    final nextIsList =
        nextSubPath != null ? int.tryParse(nextSubPath) != null : false;

    if (i == pathList.length - 1) {
      // destination
      if (subPathInt != null) {
        if (!(curr is List)) {
          throw 'The leaf "$destinationPath" cannot be added because the parent of "$subPathInt" is not a list.';
        }
        final added = addToList(
          list: curr,
          index: subPathInt,
          element: leafContent,
          overwrite: true,
        );

        if (!added) {
          throw 'The leaf "$destinationPath" cannot be added because there are missing indices.';
        }
      } else {
        if (!(curr is Map)) {
          throw 'The leaf "$destinationPath" cannot be added because the parent of "$subPath" is not a map.';
        }
        curr[subPath] = leafContent;
      }
    } else {
      // make sure that the path to the leaf exists
      if (subPathInt != null) {
        // list mode
        if (!(curr is List)) {
          throw 'The leaf "$destinationPath" cannot be added because the parent of "$subPathInt" is not a list.';
        }

        final added = addToList(
          list: curr,
          index: subPathInt,
          element: nextIsList ? <dynamic>[] : <String, dynamic>{},
          overwrite: false,
        );

        if (!added) {
          throw 'The leaf "$destinationPath" cannot be added because there are missing indices.';
        }

        curr = curr[subPathInt];
      } else {
        // map mode
        if (!(curr is Map)) {
          throw 'The leaf "$destinationPath" cannot be added because the parent of "$subPath" is not a map.';
        }

        if (!curr.containsKey(subPath)) {
          // path touches first time the tree, make sure the path exists
          // but do not overwrite,
          // so previous [addStringToMap] calls get not lost
          curr[subPath] = nextIsList ? <dynamic>[] : <String, dynamic>{};
        }

        curr = curr[subPath];
      }
    }
  }
}