Add StateTree leafs & ExtTree data ZKI calculation

db/statedb/utils.go

@@ -1,9 +1,12 @@
 package statedb
 
 import (
+	"math/big"
+
 	ethCommon "github.com/ethereum/go-ethereum/common"
 	"github.com/hermeznetwork/hermez-node/common"
 	"github.com/iden3/go-iden3-crypto/babyjub"
+	"github.com/iden3/go-merkletree"
 )
 
 // TODO
@@ -15,3 +18,28 @@ func (s *StateDB) getIdxByEthAddr(addr ethCommon.Address) common.Idx {
 func (s *StateDB) getIdxByBJJ(pk *babyjub.PublicKey) common.Idx {
 	return common.Idx(0)
 }
+
+func siblingsToZKInputFormat(s []*merkletree.Hash) []*big.Int {
+	b := make([]*big.Int, len(s))
+	for i := 0; i < len(s); i++ {
+		b[i] = s[i].BigInt()
+	}
+	return b
+}
+
+// BJJCompressedTo256BigInts returns a [256]*big.Int array with the bit
+// representation of the babyjub.PublicKeyComp
+func BJJCompressedTo256BigInts(pkComp babyjub.PublicKeyComp) [256]*big.Int {
+	var r [256]*big.Int
+	b := pkComp[:]
+
+	for i := 0; i < 256; i++ {
+		if b[i/8]&(1<<(i%8)) == 0 {
+			r[i] = big.NewInt(0)
+		} else {
+			r[i] = big.NewInt(1)
+		}
+	}
+
+	return r
+}