ReceiptEventContent.fromJson constructor

ReceiptEventContent.fromJson(Map<String, dynamic> json)

Implementation

factory ReceiptEventContent.fromJson(Map<String, dynamic> json) {
  // Example data:
  // {
  //   "$I": {
  //     "m.read": {
  //       "@user:example.org": {
  //         "ts": 1661384801651,
  //         "thread_id": "main" // because `I` is not in a thread, but is a threaded receipt
  //       }
  //     }
  //   },
  //   "$E": {
  //     "m.read": {
  //       "@user:example.org": {
  //         "ts": 1661384801651,
  //         "thread_id": "$A" // because `E` is in Thread `A`
  //       }
  //     }
  //   },
  //   "$D": {
  //     "m.read": {
  //       "@user:example.org": {
  //         "ts": 1661384801651
  //         // no `thread_id` because the receipt is *unthreaded*
  //       }
  //     }
  //   }
  // }

  final Map<String, Map<ReceiptType, Map<String, ReceiptData>>> receipts = {};
  for (final eventIdEntry in json.entries) {
    final eventId = eventIdEntry.key;
    final contentForEventId = eventIdEntry.value;

    if (!eventId.startsWith('\$') || contentForEventId is! Map) continue;

    for (final receiptTypeEntry in contentForEventId.entries) {
      if (receiptTypeEntry.key is! String) continue;

      final receiptType = ReceiptType.values.fromString(receiptTypeEntry.key);
      final contentForReceiptType = receiptTypeEntry.value;

      if (receiptType == null || contentForReceiptType is! Map) continue;

      for (final userIdEntry in contentForReceiptType.entries) {
        final userId = userIdEntry.key;
        final receiptContent = userIdEntry.value;

        if (userId is! String ||
            !userId.isValidSDNId ||
            receiptContent is! Map) continue;

        final ts = receiptContent['ts'];
        final threadId = receiptContent['thread_id'];

        if (ts is int && (threadId == null || threadId is String)) {
          ((receipts[eventId] ??= {})[receiptType] ??= {})[userId] =
              ReceiptData(ts, threadId: threadId);
        }
      }
    }
  }

  return ReceiptEventContent(receipts);
}