[#232] Use contract to get container info

Signed-off-by: Nikita Zinkevich <n.zinkevich@yadro.com>

internal/service/contracts/util/util.go

@@ -0,0 +1,34 @@
+package util
+
+import (
+	"fmt"
+	"strings"
+
+	"git.frostfs.info/TrueCloudLab/frostfs-sdk-go/container"
+	"git.frostfs.info/TrueCloudLab/frostfs-sdk-go/ns"
+	"github.com/nspcc-dev/neo-go/pkg/util"
+)
+
+// ResolveContractHash determine contract hash by resolving NNS name.
+func ResolveContractHash(contractHash, rpcAddress string) (util.Uint160, error) {
+	if hash, err := util.Uint160DecodeStringLE(contractHash); err == nil {
+		return hash, nil
+	}
+
+	splitName := strings.Split(contractHash, ".")
+	if len(splitName) != 2 {
+		return util.Uint160{}, fmt.Errorf("invalid contract name: '%s'", contractHash)
+	}
+
+	var domain container.Domain
+	domain.SetName(splitName[0])
+	domain.SetZone(splitName[1])
+
+	var nns ns.NNS
+	if err := nns.Dial(rpcAddress); err != nil {
+		return util.Uint160{}, fmt.Errorf("dial nns %s: %w", rpcAddress, err)
+	}
+	defer nns.Close()
+
+	return nns.ResolveContractHash(domain)
+}