add disputes coordinator

dot/parachain/dispute/coordinator.go

@@ -0,0 +1,68 @@
+package dispute
+
+import (
+	"fmt"
+	"github.com/google/btree"
+	"time"
+)
+
+type DisputeCoordinatorSubsystem interface {
+	Run() error
+}
+
+type disputeCoordinator struct {
+	db Backend
+}
+
+func (d *disputeCoordinator) Run() error {
+	if err := d.initialize(); err != nil {
+		return fmt.Errorf("initialize dispute coordinator: %w", err)
+	}
+
+	// TODO: run the subsystem
+
+	return nil
+}
+
+func (d *disputeCoordinator) initialize() error {
+	// TODO: wait for the first leaf
+
+	if err := d.handleStartup(); err != nil {
+		return fmt.Errorf("handle startup: %w", err)
+	}
+
+	// TODO: update db on disk
+
+	//TODO implement me
+	panic("implement me")
+}
+
+func (d *disputeCoordinator) handleStartup() error {
+	var now = time.Now().Unix()
+	activeDisputes, err := d.db.GetActiveDisputes(now)
+	if err != nil {
+		return fmt.Errorf("get active disputes: %w", err)
+	}
+
+	// TODO: get highest session
+
+	// TODO: check if there is a gap in cache
+
+	// TODO: prune obsolete disputes
+
+	// TODO: for every dispute in activeDisputes
+	// get candidate votes
+	// check if it is a potential spam
+	// participate if needed, if not distribute the own vote
+	activeDisputes.Descend(func(i btree.Item) bool {
+		return true
+	})
+
+	return nil
+}
+
+func NewDisputeCoordinator() DisputeCoordinatorSubsystem {
+	return &disputeCoordinator{
+		db: NewBackend(),
+	}
+}