some strange storage stuff

cart-grain.go

@@ -4,6 +4,7 @@ import (
 	"encoding/json"
 	"fmt"
 	"sync"
+	"time"
 
 	messages "git.tornberg.me/go-cart-actor/proto"
 )
@@ -89,6 +90,7 @@ type CartGrain struct {
 	mu                sync.RWMutex
 	lastItemId        int
 	lastDeliveryId    int
+	lastChange        int64           // unix seconds of last successful mutation (replay sets from event ts)
 	Id                CartId          `json:"id"`
 	Items             []*CartItem     `json:"items"`
 	TotalPrice        int64           `json:"totalPrice"`
@@ -112,8 +114,7 @@ func (c *CartGrain) GetId() CartId {
 }
 
 func (c *CartGrain) GetLastChange() int64 {
-	// Legacy event log removed; return 0 to indicate no persisted mutation history.
-	return 0
+	return c.lastChange
 }
 
 func (c *CartGrain) GetCurrentState() (*CartGrain, error) {
@@ -269,6 +270,13 @@ func (c *CartGrain) Apply(content interface{}, isReplay bool) (*CartGrain, error
 		}
 		return nil, err
 	}
+
+	// Sliding TTL: update lastChange only for non-replay successful mutations.
+	if updated != nil && !isReplay {
+		c.lastChange = time.Now().Unix()
+		_ = AppendCartEvent(c.Id, content)
+	}
+
 	return updated, nil
 }