wip(btc:): prepare processor

Co-authored-by: Gaze <gazenw@users.noreply.github.com>

modules/bitcoin/processor.go

@@ -0,0 +1,32 @@
+package bitcoin
+
+import (
+	"context"
+
+	"github.com/gaze-network/indexer-network/core/indexers"
+	"github.com/gaze-network/indexer-network/core/types"
+)
+
+// Make sure to implement the BitcoinProcessor interface
+var _ indexers.BitcoinProcessor = (*Processor)(nil)
+
+type Processor struct{}
+
+func (p *Processor) Process(ctx context.Context, inputs []*types.Block) error {
+	return nil
+}
+
+func (p *Processor) CurrentBlock() (types.BlockHeader, error) {
+	// TODO: return the latest indexed block header
+	return types.BlockHeader{}, nil
+}
+
+func (p *Processor) PrepareData(ctx context.Context, from, to int64) ([]*types.Block, error) {
+	// TODO: move out to a separate interface (e.g. DataFetcher)
+	return nil, nil
+}
+
+func (p *Processor) RevertData(ctx context.Context, from types.BlockHeader) error {
+	// TODO: revert synced data to the specified block for re-indexing
+	return nil
+}