op-challenger: Add logging

op-challenger/fault/agent.go

@@ -3,6 +3,8 @@ package fault
 import (
 	"context"
 	"sync"
+
+	"github.com/ethereum/go-ethereum/log"
 )
 
 type Agent struct {
@@ -12,15 +14,17 @@ type Agent struct {
 	trace     TraceProvider
 	responder Responder
 	maxDepth  int
+	log       log.Logger
 }
 
-func NewAgent(game Game, maxDepth int, trace TraceProvider, responder Responder) Agent {
+func NewAgent(game Game, maxDepth int, trace TraceProvider, responder Responder, log log.Logger) Agent {
 	return Agent{
 		game:      game,
 		solver:    NewSolver(maxDepth, trace),
 		trace:     trace,
 		responder: responder,
 		maxDepth:  maxDepth,
+		log:       log,
 	}
 }
 
@@ -45,12 +49,23 @@ func (a *Agent) PerformActions() {
 
 // move determines & executes the next move given a claim pair
 func (a *Agent) move(claim, parent Claim) error {
-	move, err := a.solver.NextMove(claim)
-	if err != nil || move == nil {
+	nextMove, err := a.solver.NextMove(claim)
+	if err != nil {
+		a.log.Warn("Failed to execute the next move", "err", err)
 		return err
 	}
-	if a.game.IsDuplicate(*move) {
+	if nextMove == nil {
+		a.log.Info("No next move")
+		return nil
+	}
+	move := *nextMove
+	log := a.log.New("is_defend", move.DefendsParent(), "depth", move.Depth(), "index_at_depth", move.IndexAtDepth(), "value", move.Value,
+		"letter", string(move.Value[31:]), "trace_index", move.Value[30],
+		"parent_letter", string(claim.Value[31:]), "parent_trace_index", claim.Value[30])
+	if a.game.IsDuplicate(move) {
+		log.Debug("Duplicate move")
 		return nil
 	}
-	return a.responder.Respond(context.TODO(), *move)
+	log.Info("Performing move")
+	return a.responder.Respond(context.TODO(), move)
 }