encode method

@override Uint8List encode(dynamic value)

ABI-encode value as a 32-byte-aligned Uint8List. For dynamic types, returns the tail; the caller places the offset in the head.

Implementation

@override
Uint8List encode(dynamic value) {
  final list = value as List;
  final length = fixedLength ?? list.length;
  if (fixedLength != null && list.length != fixedLength) {
    throw ArgumentError(
        '$name expects $fixedLength elements, got ${list.length}');
  }

  if (!elementType.isDynamic) {
    final parts = <Uint8List>[];
    if (fixedLength == null) {
      parts.add(_uint256(BigInt.from(length)));
    }
    for (var i = 0; i < length; i++) {
      parts.add(elementType.encode(list[i]));
    }
    return _concat(parts);
  }

  // Dynamic elements: offsets in head, data in tail.
  final heads = <Uint8List>[];
  final tails = <Uint8List>[];

  if (fixedLength == null) {
    heads.add(_uint256(BigInt.from(length)));
  }

  var tailOffset = length * 32;
  final encodedItems = <Uint8List>[];
  for (var i = 0; i < length; i++) {
    final encoded = elementType.encode(list[i]);
    encodedItems.add(encoded);
  }
  for (var i = 0; i < length; i++) {
    heads.add(_uint256(BigInt.from(tailOffset)));
    tailOffset += encodedItems[i].length;
    tails.add(encodedItems[i]);
  }

  return _concat([...heads, ...tails]);
}