Initial commit

server/internal/store/memory/snapshot.go

@@ -0,0 +1,47 @@
+package memory
+
+import (
+	"encoding/json"
+	"fmt"
+	"log"
+	"os"
+	"path/filepath"
+
+	"lunar-tear/server/internal/store"
+)
+
+func snapshotPath(dir string, sceneId int32) string {
+	return filepath.Join(dir, fmt.Sprintf("scene_%d.json", sceneId))
+}
+
+func saveSnapshot(user *store.UserState, dir string) {
+	sceneId := user.MainQuest.CurrentQuestSceneId
+	if sceneId == 0 {
+		return
+	}
+	data, err := json.MarshalIndent(user, "", "  ")
+	if err != nil {
+		log.Printf("[snapshot] marshal error for scene=%d: %v", sceneId, err)
+		return
+	}
+	path := snapshotPath(dir, sceneId)
+	if err := os.WriteFile(path, data, 0644); err != nil {
+		log.Printf("[snapshot] write error for scene=%d: %v", sceneId, err)
+		return
+	}
+	log.Printf("[snapshot] saved scene=%d (%d bytes)", sceneId, len(data))
+}
+
+func loadSnapshot(dir string, sceneId int32) (*store.UserState, error) {
+	path := snapshotPath(dir, sceneId)
+	data, err := os.ReadFile(path)
+	if err != nil {
+		return nil, fmt.Errorf("read snapshot scene=%d: %w", sceneId, err)
+	}
+	var user store.UserState
+	if err := json.Unmarshal(data, &user); err != nil {
+		return nil, fmt.Errorf("unmarshal snapshot scene=%d: %w", sceneId, err)
+	}
+	user.EnsureMaps()
+	return &user, nil
+}