[#51] alphabet: Support notary contract

Signed-off-by: Alex Vanin <alexey@nspcc.ru>

alphabet/alphabet_contract.go

@@ -2,9 +2,7 @@ package alphabetcontract
 
 import (
 	"github.com/nspcc-dev/neo-go/pkg/interop"
-	"github.com/nspcc-dev/neo-go/pkg/interop/binary"
 	"github.com/nspcc-dev/neo-go/pkg/interop/contract"
-	"github.com/nspcc-dev/neo-go/pkg/interop/crypto"
 	"github.com/nspcc-dev/neo-go/pkg/interop/native/gas"
 	"github.com/nspcc-dev/neo-go/pkg/interop/native/management"
 	"github.com/nspcc-dev/neo-go/pkg/interop/native/neo"
@@ -15,10 +13,13 @@ import (
 
 const (
 	netmapKey = "netmapScriptHash"
-	indexKey  = "index"
+	proxyKey  = "proxyScriptHash"
-	totalKey  = "threshold"
+
-	nameKey   = "name"
+	indexKey = "index"
-	voteKey   = "ballots"
+	totalKey = "threshold"
+	nameKey  = "name"
+
+	version = 1
 )
 
 var ctx storage.Context
@@ -35,23 +36,22 @@ func OnNEP17Payment(from interop.Hash160, amount int, data interface{}) {
 	}
 }
 
-func Init(owner interop.Hash160, addrNetmap []byte, name string, index, total int) {
+func Init(owner interop.Hash160, addrNetmap, addrProxy interop.Hash160, name string, index, total int) {
 	if !common.HasUpdateAccess(ctx) {
 		panic("only owner can reinitialize contract")
 	}
 
-	if len(addrNetmap) != 20 {
+	if len(addrNetmap) != 20 || len(addrProxy) != 20 {
 		panic("incorrect length of contract script hash")
 	}
 
 	storage.Put(ctx, common.OwnerKey, owner)
 	storage.Put(ctx, netmapKey, addrNetmap)
+	storage.Put(ctx, proxyKey, addrProxy)
 	storage.Put(ctx, nameKey, name)
 	storage.Put(ctx, indexKey, index)
 	storage.Put(ctx, totalKey, total)
 
-	common.SetSerialized(ctx, voteKey, []common.Ballot{})
-
 	runtime.Log(name + " contract initialized")
 }
 
@@ -115,35 +115,40 @@ func Emit() bool {
 
 	contractHash := runtime.GetExecutingScriptHash()
 
-	_ = neo.Transfer(contractHash, contractHash, neo.BalanceOf(contractHash), nil)
+	neo.Transfer(contractHash, contractHash, neo.BalanceOf(contractHash), nil)
 
 	gasBalance := gas.BalanceOf(contractHash)
-	gasPerNode := gasBalance * 7 / 8 / len(innerRingKeys)
+	proxyAddr := storage.Get(ctx, proxyKey).(interop.Hash160)
 
-	if gasPerNode == 0 {
+	proxyGas := gasBalance / 2
+	if proxyGas == 0 {
 		runtime.Log("no gas to emit")
 		return false
 	}
 
-	for i := range innerRingKeys {
+	gas.Transfer(contractHash, proxyAddr, proxyGas, nil)
-		node := innerRingKeys[i]
+	runtime.Log("utility token has been emitted to proxy contract")
-		address := contract.CreateStandardAccount(node.PublicKey)
 
-		_ = gas.Transfer(contractHash, address, gasPerNode, nil)
+	gasPerNode := gasBalance / 2 * 7 / 8 / len(innerRingKeys)
+
+	if gasPerNode != 0 {
+		for _, node := range innerRingKeys {
+			address := contract.CreateStandardAccount(node.PublicKey)
+			gas.Transfer(contractHash, address, gasPerNode, nil)
+		}
+
+		runtime.Log("utility token has been emitted to inner ring nodes")
 	}
 
-	runtime.Log("utility token has been emitted to inner ring nodes")
 	return true
 }
 
 func Vote(epoch int, candidates [][]byte) {
-	innerRingKeys := irList()
-	threshold := total()/3*2 + 1
 	index := index()
 	name := name()
 
-	key := common.InnerRingInvoker(innerRingKeys)
+	multiaddr := common.InnerRingMultiAddressViaStorage(ctx, netmapKey)
-	if len(key) == 0 {
+	if !runtime.CheckWitness(multiaddr) {
 		panic("invalid invoker")
 	}
 
@@ -152,22 +157,14 @@ func Vote(epoch int, candidates [][]byte) {
 		panic("invalid epoch")
 	}
 
-	id := voteID(epoch, candidates)
+	candidate := candidates[index%len(candidates)]
-	n := vote(ctx, curEpoch, id, key)
+	address := runtime.GetExecutingScriptHash()
 
-	if n >= threshold {
+	ok := neo.Vote(address, candidate)
-		candidate := candidates[index%len(candidates)]
+	if ok {
-		address := runtime.GetExecutingScriptHash()
+		runtime.Log(name + ": successfully voted for validator")
-
-		ok := neo.Vote(address, candidate)
-		if ok {
-			runtime.Log(name + ": successfully voted for validator")
-			removeVotes(ctx, id)
-		} else {
-			runtime.Log(name + ": vote has been failed")
-		}
 	} else {
-		runtime.Log(name + ": saved vote for validator")
+		runtime.Log(name + ": vote has been failed")
 	}
 
 	return
@@ -177,85 +174,6 @@ func Name() string {
 	return name()
 }
 
-func vote(ctx storage.Context, epoch int, id, from []byte) int {
+func Version() int {
-	var (
+	return version
-		newCandidates []common.Ballot
-		candidates    = getBallots(ctx)
-		found         = -1
-	)
-
-	for i := 0; i < len(candidates); i++ {
-		cnd := candidates[i]
-		if common.BytesEqual(cnd.ID, id) {
-			voters := cnd.Voters
-
-			for j := range voters {
-				if common.BytesEqual(voters[j], from) {
-					return len(voters)
-				}
-			}
-
-			voters = append(voters, from)
-			cnd = common.Ballot{ID: id, Voters: voters, Height: epoch}
-			found = len(voters)
-		}
-
-		// add only valid ballots with current epochs
-		if cnd.Height == epoch {
-			newCandidates = append(newCandidates, cnd)
-		}
-	}
-
-	if found < 0 {
-		voters := [][]byte{from}
-		newCandidates = append(newCandidates, common.Ballot{
-			ID:     id,
-			Voters: voters,
-			Height: epoch})
-		found = 1
-	}
-
-	common.SetSerialized(ctx, voteKey, newCandidates)
-
-	return found
-}
-
-func removeVotes(ctx storage.Context, id []byte) {
-	var (
-		newCandidates []common.Ballot
-		candidates    = getBallots(ctx)
-	)
-
-	for i := 0; i < len(candidates); i++ {
-		cnd := candidates[i]
-		if !common.BytesEqual(cnd.ID, id) {
-			newCandidates = append(newCandidates, cnd)
-		}
-	}
-
-	common.SetSerialized(ctx, voteKey, newCandidates)
-}
-
-func getBallots(ctx storage.Context) []common.Ballot {
-	data := storage.Get(ctx, voteKey)
-	if data != nil {
-		return binary.Deserialize(data.([]byte)).([]common.Ballot)
-	}
-
-	return []common.Ballot{}
-}
-
-func voteID(epoch interface{}, args [][]byte) []byte {
-	var (
-		result     []byte
-		epochBytes = epoch.([]byte)
-	)
-
-	result = append(result, epochBytes...)
-
-	for i := range args {
-		result = append(result, args[i]...)
-	}
-
-	return crypto.SHA256(result)
 }