func NewEthereumProof(proof ethereum.Proof) *Proof {
	return &Proof{
		Proof: &Proof_EthereumProof{
			EthereumProof: &proof,
		},
	}
}

func (h HeaderData) ParentHash() ([]byte, error) {
	switch data := h.Data.(type) {
	case *HeaderData_EthereumHeader:
		var header ethtypes.Header
		if err := rlp.DecodeBytes(data.EthereumHeader, &header); err != nil {
			return nil, err
		}
		return header.ParentHash.Bytes(), nil
	default:
		return nil, errors.New("unrecognized header type")
	}
}

func (h HeaderData) Validate(blockHash []byte, height int64) error {
	switch data := h.Data.(type) {
	case *HeaderData_EthereumHeader:
		return validateEthereumHeader(data.EthereumHeader, blockHash, height)
	default:
		return errors.New("unrecognized header type")
	}
}

func NewEthereumProof(proof ethereum.Proof) *Proof {
	return &Proof{
		Proof: &Proof_EthereumProof{
			EthereumProof: &proof,
		},
	}
}

func (p Proof) Verify(headerData HeaderData, txIndex int) ([]byte, error) {
	switch proof := p.Proof.(type) {
	case *Proof_EthereumProof:
		ethHeaderBytes := headerData.GetEthereumHeader()
		if ethHeaderBytes == nil {
			return nil, errors.New("can't verify ethereum proof against non-ethereum header")
		}
		var ethHeader ethtypes.Header
		err := rlp.DecodeBytes(ethHeaderBytes, &ethHeader)
		if err != nil {
			return nil, err
		}
		val, err := proof.EthereumProof.Verify(ethHeader.TxHash, txIndex)
		if err != nil {
			return nil, NewErrInvalidProof(err)
		}
		return val, nil
	default:
		return nil, errors.New("unrecognized proof type")
	}
}