Added contract_id

contract_id.go

@@ -0,0 +1,67 @@
+package hedera
+
+import (
+	"fmt"
+	"github.com/hashgraph/hedera-sdk-go/proto"
+)
+
+// ContractID is the ID for a Hedera smart contract
+type ContractID struct {
+	Shard    uint64
+	Realm    uint64
+	Contract uint64
+}
+
+// ContractIDFromString constructs a ContractID from a string formatted as `Shard.Realm.Contract` (for example "0.0.3")
+func ContractIDFromString(s string) (ContractID, error) {
+	shard, realm, num, err := idFromString(s)
+	if err != nil {
+		return ContractID{}, err
+	}
+
+	return ContractID{
+		Shard:    uint64(shard),
+		Realm:    uint64(realm),
+		Contract: uint64(num),
+	}, nil
+}
+
+// ContractIDFromSolidityAddress constructs a ContractID from a string representation of a solidity address
+func ContractIDFromSolidityAddress(s string) (ContractID, error) {
+	shard, realm, contract, err := idFromSolidityAddress(s)
+	if err != nil {
+		return ContractID{}, err
+	}
+
+	return ContractID{
+		Shard:    shard,
+		Realm:    realm,
+		Contract: contract,
+	}, nil
+}
+
+// String returns the string representation of a ContractID formatted as `Shard.Realm.Contract` (for example "0.0.3")
+func (id ContractID) String() string {
+	return fmt.Sprintf("%d.%d.%d", id.Shard, id.Realm, id.Contract)
+}
+
+// ToSolidityAddress returns the string representation of the ContractID as a solidity address.
+func (id ContractID) ToSolidityAddress() string {
+	return idToSolidityAddress(id.Shard, id.Realm, id.Contract)
+}
+
+func (id ContractID) toProto() *proto.ContractID {
+	return &proto.ContractID{
+		ShardNum:    int64(id.Shard),
+		RealmNum:    int64(id.Realm),
+		ContractNum: int64(id.Contract),
+	}
+}
+
+func contractIDFromProto(pb *proto.ContractID) ContractID {
+	return ContractID{
+		Shard:    uint64(pb.ShardNum),
+		Realm:    uint64(pb.RealmNum),
+		Contract: uint64(pb.ContractNum),
+	}
+}