feat: add counter for activated TAs

Signed-off-by: Lorenz Herzberger <lorenzherzberger@gmail.com>

x/machine/keeper/trust_anchor.go

@@ -1,6 +1,7 @@
 package keeper
 
 import (
+	"encoding/binary"
 	"errors"
 
 	"github.com/planetmint/planetmint-go/util"
@@ -16,6 +17,8 @@ func (k Keeper) StoreTrustAnchor(ctx sdk.Context, ta types.TrustAnchor, activate
 	var appendValue []byte
 	if activated {
 		appendValue = []byte{1}
+		counter := k.GetActivatedTACounter(ctx)
+		k.setActivatedTACounter(ctx, counter+1)
 	} else {
 		appendValue = []byte{0}
 	}
@@ -46,3 +49,20 @@ func (k Keeper) GetTrustAnchor(ctx sdk.Context, pubKey string) (val types.TrustA
 	}
 	return val, false, true
 }
+
+func (k Keeper) setActivatedTACounter(ctx sdk.Context, counter uint64) {
+	taCounterStore := prefix.NewStore(ctx.KVStore(k.storeKey), types.KeyPrefix(types.TAIndexKey))
+	bz := make([]byte, 8)
+	binary.BigEndian.PutUint64(bz, counter)
+	taCounterStore.Set([]byte(types.ActivatedTACounterKey), bz)
+}
+
+func (k Keeper) GetActivatedTACounter(ctx sdk.Context) (counter uint64) {
+	taCounterStore := prefix.NewStore(ctx.KVStore(k.storeKey), types.KeyPrefix(types.TAIndexKey))
+	bz := taCounterStore.Get([]byte(types.ActivatedTACounterKey))
+	if bz == nil {
+		return 0
+	}
+	counter = binary.BigEndian.Uint64(bz)
+	return
+}

x/machine/keeper/trust_anchor_test.go

@@ -69,3 +69,11 @@ func TestUpdateTrustAnchor(t *testing.T) {
 		assert.True(t, activated)
 	}
 }
+
+func TestActivatedTACounter(t *testing.T) {
+	t.Parallel()
+	keeper, ctx := keepertest.MachineKeeper(t)
+	createNTrustAnchor(t, keeper, ctx, 100)
+	counter := keeper.GetActivatedTACounter(ctx)
+	assert.Equal(t, uint64(50), counter)
+}

x/machine/types/keys.go

@@ -28,6 +28,8 @@ const (
 	LiquidAssetKey = "Machine/LiquidAsset/"
 
 	ParamsKey = "Machine/Params"
+
+	ActivatedTACounterKey = "ActivatedTACounter"
 )
 
 func KeyPrefix(p string) []byte {