feat: add Shelley protocol parameters support

Signed-off-by: Ales Verbic <[email protected]>

ledger/shelley.go

@@ -175,7 +175,7 @@ type ShelleyTransactionBody struct {
 	Withdrawals cbor.Value `cbor:"5,keyasint,omitempty"`
 	Update      struct {
 		cbor.StructAsArray
-		ProtocolParamUpdates cbor.Value
+		ProtocolParamUpdates map[Blake2b224]ShelleyProtocolParameterUpdate
 		Epoch                uint64
 	} `cbor:"6,keyasint,omitempty"`
 	MetadataHash Blake2b256 `cbor:"7,keyasint,omitempty"`
@@ -397,6 +397,25 @@ func (t *ShelleyTransaction) Cbor() []byte {
 	return cborData
 }
 
+type ShelleyProtocolParameterUpdate struct {
+	MinFeeA            uint      `cbor:"0,keyasint"`
+	MinFeeB            uint      `cbor:"1,keyasint"`
+	MaxBlockBodySize   uint      `cbor:"2,keyasint"`
+	MaxTxSize          uint      `cbor:"3,keyasint"`
+	MaxBlockHeaderSize uint      `cbor:"4,keyasint"`
+	KeyDeposit         uint      `cbor:"5,keyasint"`
+	PoolDeposit        uint      `cbor:"6,keyasint"`
+	MaxEpoch           uint      `cbor:"7,keyasint"`
+	NOpt               uint      `cbor:"8,keyasint"`
+	A0                 *cbor.Rat `cbor:"9,keyasint"`
+	Rho                *cbor.Rat `cbor:"10,keyasint"`
+	Tau                *cbor.Rat `cbor:"11,keyasint"`
+	DDecentralization  *cbor.Rat `cbor:"12,keyasint"`
+	Nonce              *cbor.Rat `cbor:"13,keyasint"`
+	ProtocolVersion    []uint    `cbor:"14,keyasint"`
+	MinUtxoValue       uint      `cbor:"15,keyasint"`
+}
+
 func NewShelleyBlockFromCbor(data []byte) (*ShelleyBlock, error) {
 	var shelleyBlock ShelleyBlock
 	if _, err := cbor.Decode(data, &shelleyBlock); err != nil {