Method WriteSequenceSignatureTree

compressor/encode.go:612–741

(tree []byte)

}

func (buf *Buffer) WriteSequenceSignatureTree(tree []byte) (EncodeType, error) {
	// Signature trees need to be encoded as N nested bytes (one per part)
	// for this we first need to count the number of parts
	if len(tree) == 0 {
		return Stateless, fmt.Errorf("signature tree is empty")
	}

	totalParts := 0
	pointer := uint(0)

	for pointer < uint(len(tree)) {
		partType := tree[pointer]
		pointer += 1

		switch partType {
		case 0x00: // EOA Signature
			pointer += (1 + 66)
		case 0x01: // Address
			pointer += (1 + 20)
		case 0x02: // Dynamic
			pointer += (1 + 20)
			// 3 bytes after address and weight are the length
			length := uint(tree[pointer])<<16 | uint(tree[pointer+1])<<8 | uint(tree[pointer+2])
			pointer += (3 + length)
		case 0x03: // Node
			pointer += 32
		case 0x04: // Branch
			// 3 bytes of length
			length := uint(tree[pointer])<<16 | uint(tree[pointer+1])<<8 | uint(tree[pointer+2])
			pointer += (3 + length)
		case 0x05: // Subdigest
			pointer += 32
		case 0x06: // Nested
			pointer += 3
			// 3 bytes of length
			length := uint(tree[pointer])<<16 | uint(tree[pointer+1])<<8 | uint(tree[pointer+2])
			pointer += (3 + length)
		default:
			return Stateless, fmt.Errorf("invalid signature part type %d", partType)
		}

		totalParts += 1
	}

	if totalParts > 1 {
		if totalParts > 255 {
			buf.commitUint(FLAG_NESTED_N_FLAGS_L)
			buf.commitByte(byte(totalParts >> 8))
			buf.commitByte(byte(totalParts))
		} else {
			buf.commitUint(FLAG_NESTED_N_FLAGS_S)
			buf.commitByte(byte(totalParts))
		}
	}

	buf.end([]byte{}, Stateless)

	// Now we need to encode every nested part, one for each signature part