Track age and weight

server/main.go

@@ -17,19 +17,98 @@ import (
 )
 
 type Event struct {
-	ID        string `json:"id"`
-	Type      string `json:"type"`
-	At        int64  `json:"at"`
-	Note      string `json:"note"`
-	PhotoID   string `json:"photoId,omitempty"`
-	UpdatedAt int64  `json:"updatedAt"`
-	Deleted   bool   `json:"deleted,omitempty"`
+	ID        string  `json:"id"`
+	Type      string  `json:"type"`
+	At        int64   `json:"at"`
+	Note      string  `json:"note"`
+	PhotoID   string  `json:"photoId,omitempty"`
+	Weight    float64 `json:"weight,omitempty"` // kilograms, for "weight" events
+	UpdatedAt int64   `json:"updatedAt"`
+	Deleted   bool    `json:"deleted,omitempty"`
 }
 
 var uuidRE = regexp.MustCompile(`^[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}$`)
 
 func validUUID(s string) bool { return uuidRE.MatchString(s) }
 
+var birthdayRE = regexp.MustCompile(`^\d{4}-\d{2}-\d{2}$`)
+
+func validBirthday(s string) bool { return s == "" || birthdayRE.MatchString(s) }
+
+// Config is the shared puppy profile (name + birthday). It lives on the host so
+// every client sees the same values without configuring each device. UpdatedAt
+// drives last-write-wins, mirroring how events sync.
+type Config struct {
+	Name      string `json:"name"`
+	Birthday  string `json:"birthday"`
+	UpdatedAt int64  `json:"updatedAt"`
+}
+
+type ConfigStore struct {
+	path string
+	mu   sync.Mutex
+	cfg  Config
+}
+
+func newConfigStore(path string) (*ConfigStore, error) {
+	cs := &ConfigStore{path: path}
+	f, err := os.Open(path)
+	if err != nil {
+		if errors.Is(err, fs.ErrNotExist) {
+			return cs, nil
+		}
+		return nil, err
+	}
+	defer f.Close()
+	if err := json.NewDecoder(f).Decode(&cs.cfg); err != nil && !errors.Is(err, io.EOF) {
+		return nil, err
+	}
+	return cs, nil
+}
+
+func (cs *ConfigStore) get() Config {
+	cs.mu.Lock()
+	defer cs.mu.Unlock()
+	return cs.cfg
+}
+
+// merge applies an incoming config with last-write-wins by UpdatedAt and
+// returns the resulting stored config (which the caller sends back).
+func (cs *ConfigStore) merge(in Config) (Config, error) {
+	cs.mu.Lock()
+	defer cs.mu.Unlock()
+	if in.UpdatedAt > cs.cfg.UpdatedAt {
+		cs.cfg = in
+		if err := cs.saveLocked(); err != nil {
+			return cs.cfg, err
+		}
+	}
+	return cs.cfg, nil
+}
+
+// Caller must hold cs.mu.
+func (cs *ConfigStore) saveLocked() error {
+	if err := os.MkdirAll(filepath.Dir(cs.path), 0o755); err != nil {
+		return err
+	}
+	tmp := cs.path + ".tmp"
+	f, err := os.Create(tmp)
+	if err != nil {
+		return err
+	}
+	enc := json.NewEncoder(f)
+	enc.SetIndent("", "  ")
+	if err := enc.Encode(cs.cfg); err != nil {
+		f.Close()
+		os.Remove(tmp)
+		return err
+	}
+	if err := f.Close(); err != nil {
+		return err
+	}
+	return os.Rename(tmp, cs.path)
+}
+
 type Store struct {
 	path string
 	mu   sync.Mutex
@@ -143,6 +222,11 @@ func main() {
 		log.Fatalf("load store: %v", err)
 	}
 
+	configStore, err := newConfigStore(filepath.Join(filepath.Dir(*dataPath), "config.json"))
+	if err != nil {
+		log.Fatalf("load config: %v", err)
+	}
+
 	photosDir := filepath.Join(filepath.Dir(*dataPath), "photos")
 	if err := os.MkdirAll(photosDir, 0o755); err != nil {
 		log.Fatalf("mkdir photos: %v", err)
@@ -174,6 +258,43 @@ func main() {
 		})
 	})
 
+	// GET  /api/config — return the shared puppy profile.
+	// PUT  /api/config — update it (last-write-wins by updatedAt).
+	mux.HandleFunc("/api/config", func(w http.ResponseWriter, r *http.Request) {
+		writeConfig := func(c Config) {
+			w.Header().Set("Content-Type", "application/json")
+			w.Header().Set("Cache-Control", "no-store")
+			_ = json.NewEncoder(w).Encode(c)
+		}
+		switch r.Method {
+		case http.MethodGet:
+			writeConfig(configStore.get())
+		case http.MethodPut, http.MethodPost:
+			var in Config
+			if err := json.NewDecoder(io.LimitReader(r.Body, 1<<16)).Decode(&in); err != nil {
+				http.Error(w, "bad json: "+err.Error(), http.StatusBadRequest)
+				return
+			}
+			in.Name = strings.TrimSpace(in.Name)
+			if len(in.Name) > 100 {
+				in.Name = in.Name[:100]
+			}
+			if !validBirthday(in.Birthday) {
+				http.Error(w, "invalid birthday (want YYYY-MM-DD)", http.StatusBadRequest)
+				return
+			}
+			merged, err := configStore.merge(in)
+			if err != nil {
+				log.Printf("config save: %v", err)
+				http.Error(w, "server error", http.StatusInternalServerError)
+				return
+			}
+			writeConfig(merged)
+		default:
+			http.Error(w, "method not allowed", http.StatusMethodNotAllowed)
+		}
+	})
+
 	mux.HandleFunc("/healthz", func(w http.ResponseWriter, r *http.Request) {
 		w.Write([]byte("ok"))
 	})