Implement core btc handling logic

app/app.go

@@ -336,7 +336,19 @@ func NewBabylonApp(
 
 	// TODO for now use mocks, as soon as Checkpoining and lightClient will have correct interfaces
 	// change to correct implementations
-	app.BtcCheckpointKeeper = btccheckpointkeeper.NewKeeper(appCodec, keys[btccheckpointtypes.StoreKey], keys[btccheckpointtypes.MemStoreKey], app.GetSubspace(btccheckpointtypes.ModuleName), btccheckpointtypes.MockBTCLightClientKeeper{}, btccheckpointtypes.MockCheckpointingKeeper{})
+	app.BtcCheckpointKeeper =
+		btccheckpointkeeper.NewKeeper(
+			appCodec,
+			keys[btccheckpointtypes.StoreKey],
+			keys[btccheckpointtypes.MemStoreKey],
+			app.GetSubspace(btccheckpointtypes.ModuleName),
+			btccheckpointtypes.MockBTCLightClientKeeper{},
+			btccheckpointtypes.MockCheckpointingKeeper{},
+			// TODO decide on proper values for those constants, also those should be taken
+			// from some global config
+			6,
+			10,
+		)
 	app.CheckpointingKeeper = checkpointingkeeper.NewKeeper(appCodec, keys[checkpointingtypes.StoreKey], keys[checkpointingtypes.MemStoreKey], app.EpochingKeeper, app.GetSubspace(checkpointingtypes.ModuleName))
 	// create evidence keeper with router
 	evidenceKeeper := evidencekeeper.NewKeeper(

proto/babylon/btccheckpoint/btccheckpoint.proto

@@ -26,6 +26,23 @@ message SubmissionKey {
   repeated TransactionKey key = 1;
 }
 
+enum EpochStatus {
+  option (gogoproto.goproto_enum_prefix) = false;
+  // SUBMITTED Epoch is in submitted state when at least on checkpoint from it
+  // is included in bitcoin
+  EPOCH_STATUS_SUBMITTED = 0 [(gogoproto.enumvalue_customname) = "Submitted"];
+  // CONFIRMED Epoch is in confirmed state when at least on checkpoint from it
+  // is included in bitcoin and at least k-deep on main chain
+  EPOCH_STATUS_CONFIRMED = 1 [(gogoproto.enumvalue_customname) = "Confirmed"];
+  // FINALIZED Epoch is in confirmed state when at least on checkpoint from it
+  // is included in bitcoin and at least w-deep on main chain
+  EPOCH_STATUS_FINALIZED = 2 [(gogoproto.enumvalue_customname) = "Finalized"];
+  // SIGNED Epoch does not have any submissions or all of its submission are not on
+  // main chain
+  EPOCH_STATUS_SIGNED = 3 [(gogoproto.enumvalue_customname) = "Signed"];
+}
+
+
 // TODO: Determine if we should keep any block number or depth info.
 // On one hand it may be usefull to determine if block is stable or not, on other
 // depth/block number info, without context (i.e info about chain) is pretty useless
@@ -40,6 +57,8 @@ message SubmissionData {
   // message, and store only those. Another point is that it is not that simple
   // to recover sender of btc tx.
   repeated bytes btctransaction = 2;
+
+  uint64 epoch = 3;
 }
 
 // Data stored in db and indexed by epoch number
@@ -48,5 +67,11 @@ message EpochData {
   // List of all received checkpoints during this epoch, sorted by order of
   // submission.
   repeated SubmissionKey key = 1;
+
+  // Current state of epoch.
+  EpochStatus status = 2;
+
+  // Required to comunicate with checkpoint module about checkpoint status
+  bytes raw_checkpoint = 3;
 }
 

x/btccheckpoint/keeper/hooks.go

@@ -0,0 +1,35 @@
+package keeper
+
+import (
+	ltypes "github.com/babylonchain/babylon/x/btclightclient/types"
+	etypes "github.com/babylonchain/babylon/x/epoching/types"
+	sdk "github.com/cosmos/cosmos-sdk/types"
+)
+
+// Helper interface to be sure Hooks implement both epoching and light client hooks
+type HandledHooks interface {
+	ltypes.BTCLightClientHooks
+	etypes.EpochingHooks
+}
+
+type Hooks struct {
+	k Keeper
+}
+
+var _ HandledHooks = Hooks{}
+
+func (k Keeper) Hooks() Hooks { return Hooks{k} }
+
+func (h Hooks) AfterBTCRollBack(ctx sdk.Context, headerInfo *ltypes.BTCHeaderInfo) {
+	h.k.OnTipChange(ctx)
+}
+
+func (h Hooks) AfterBTCRollForward(ctx sdk.Context, headerInfo *ltypes.BTCHeaderInfo) {
+	h.k.OnTipChange(ctx)
+}
+
+func (h Hooks) AfterEpochBegins(ctx sdk.Context, epoch uint64) {}
+
+func (h Hooks) AfterEpochEnds(ctx sdk.Context, epoch uint64) {}
+
+func (h Hooks) BeforeSlashThreshold(ctx sdk.Context, valSet etypes.ValidatorSet) {}