feat: notification enhancement

internal/handler/notification.go

@@ -2,6 +2,7 @@ package handler
 
 import (
 	"encoding/json"
+	"errors"
 	"net/http"
 
 	"github.com/prabhupadasays/spsays-bff/internal/middleware"
@@ -51,6 +52,48 @@ func (h *NotificationHandler) MarkAllRead(w http.ResponseWriter, r *http.Request
 	response.NoContent(w)
 }
 
+// GetPrefs — GET /notifications/prefs. The resolved Settings matrix:
+// {"prefs": {"follows": {"in_app": true, "email": true, "push": true}, …}}.
+func (h *NotificationHandler) GetPrefs(w http.ResponseWriter, r *http.Request) {
+	uid := middleware.UserID(r.Context())
+	matrix, err := h.svc.PrefMatrix(r.Context(), uid)
+	if err != nil {
+		response.Error(w, http.StatusInternalServerError, "could not load notification preferences")
+		return
+	}
+	response.JSON(w, http.StatusOK, map[string]any{"prefs": matrix})
+}
+
+// UpdatePrefs — PUT /notifications/prefs { event, channel, enabled }. Writes
+// one matrix cell; returns the full re-resolved matrix so the client can
+// render authoritative state.
+func (h *NotificationHandler) UpdatePrefs(w http.ResponseWriter, r *http.Request) {
+	uid := middleware.UserID(r.Context())
+	var req struct {
+		Event   string `json:"event"`
+		Channel string `json:"channel"`
+		Enabled bool   `json:"enabled"`
+	}
+	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
+		response.Error(w, http.StatusBadRequest, "invalid JSON body")
+		return
+	}
+	if err := h.svc.SetPref(r.Context(), uid, req.Event, req.Channel, req.Enabled); err != nil {
+		if errors.Is(err, service.ErrUnknownPref) {
+			response.Error(w, http.StatusBadRequest, "unknown event or channel")
+			return
+		}
+		response.Error(w, http.StatusInternalServerError, "could not update notification preferences")
+		return
+	}
+	matrix, err := h.svc.PrefMatrix(r.Context(), uid)
+	if err != nil {
+		response.Error(w, http.StatusInternalServerError, "could not load notification preferences")
+		return
+	}
+	response.JSON(w, http.StatusOK, map[string]any{"prefs": matrix})
+}
+
 type emailPrefsResp struct {
 	LikeEmails bool `json:"like_emails"`
 }