feat(photos): добавить пресеты кривой и починить переключение фото

- PCHIP для предпросмотра и серверного рендера
- пресеты всех каналов в профиле, импорт и экспорт
- мерж настроек auth без потери разделов
- сохранение вкладки и правок текущего фото при переключении

backend/internal/auth/handlers.go

@@ -4,7 +4,10 @@ import (
 	"encoding/json"
 	"fmt"
 	"io"
+	"math"
 	"net/http"
+	"strings"
+	"unicode/utf8"
 
 	"github.com/gin-gonic/gin"
 
@@ -181,6 +184,9 @@ const (
 	maxLabelEntries       = 500
 	maxPreferenceKeyLen   = 128
 	maxPreferenceValueLen = 128
+	maxCurvePresets       = 100
+	maxCurvePresetNameLen = 64
+	maxCurvePresetPoints  = 16
 )
 
 type photoInfoPreferences struct {
@@ -188,33 +194,102 @@ type photoInfoPreferences struct {
 	Labels  map[string]string `json:"labels,omitempty"`
 }
 
+type curvePresetPoint struct {
+	X float64 `json:"x"`
+	Y float64 `json:"y"`
+}
+
+type curvePresetChannels struct {
+	RGB   []curvePresetPoint `json:"rgb"`
+	Red   []curvePresetPoint `json:"red"`
+	Green []curvePresetPoint `json:"green"`
+	Blue  []curvePresetPoint `json:"blue"`
+}
+
+type curvePreset struct {
+	Name     string              `json:"name"`
+	Channels curvePresetChannels `json:"channels"`
+}
+
 type preferencesPayload struct {
-	PhotoInfo *photoInfoPreferences `json:"photo_info,omitempty"`
+	PhotoInfo    *photoInfoPreferences `json:"photo_info,omitempty"`
+	CurvePresets *[]curvePreset        `json:"curve_presets,omitempty"`
+}
+
+// normalize trims preset names before they are validated and stored.
+func (p *preferencesPayload) normalize() {
+	if p.CurvePresets == nil {
+		return
+	}
+	for i := range *p.CurvePresets {
+		(*p.CurvePresets)[i].Name = strings.TrimSpace((*p.CurvePresets)[i].Name)
+	}
 }
 
 func (p preferencesPayload) validate() error {
 	pi := p.PhotoInfo
-	if pi == nil {
-		return nil
-	}
-	if len(pi.Visible) > maxVisibleAttrs {
-		return fmt.Errorf("too many visible attributes")
-	}
-	for _, k := range pi.Visible {
-		if k == "" || len(k) > maxPreferenceKeyLen {
-			return fmt.Errorf("invalid visible attribute key")
+	if pi != nil {
+		if len(pi.Visible) > maxVisibleAttrs {
+			return fmt.Errorf("too many visible attributes")
+		}
+		for _, k := range pi.Visible {
+			if k == "" || len(k) > maxPreferenceKeyLen {
+				return fmt.Errorf("invalid visible attribute key")
+			}
+		}
+		if len(pi.Labels) > maxLabelEntries {
+			return fmt.Errorf("too many label overrides")
+		}
+		for k, v := range pi.Labels {
+			if k == "" || len(k) > maxPreferenceKeyLen {
+				return fmt.Errorf("invalid label key")
+			}
+			if len(v) > maxPreferenceValueLen {
+				return fmt.Errorf("label value too long")
+			}
 		}
 	}
-	if len(pi.Labels) > maxLabelEntries {
-		return fmt.Errorf("too many label overrides")
+	if p.CurvePresets != nil {
+		return validateCurvePresets(*p.CurvePresets)
 	}
-	for k, v := range pi.Labels {
-		if k == "" || len(k) > maxPreferenceKeyLen {
-			return fmt.Errorf("invalid label key")
+	return nil
+}
+
+func validateCurvePresets(presets []curvePreset) error {
+	if len(presets) > maxCurvePresets {
+		return fmt.Errorf("too many curve presets")
+	}
+	names := make(map[string]struct{}, len(presets))
+	for _, preset := range presets {
+		if preset.Name == "" || utf8.RuneCountInString(preset.Name) > maxCurvePresetNameLen {
+			return fmt.Errorf("invalid curve preset name")
 		}
-		if len(v) > maxPreferenceValueLen {
-			return fmt.Errorf("label value too long")
+		channels := []struct {
+			name   string
+			points []curvePresetPoint
+		}{
+			{"rgb", preset.Channels.RGB},
+			{"red", preset.Channels.Red},
+			{"green", preset.Channels.Green},
+			{"blue", preset.Channels.Blue},
 		}
+		for _, channel := range channels {
+			if len(channel.points) < 2 || len(channel.points) > maxCurvePresetPoints {
+				return fmt.Errorf("invalid curve preset points for %s", channel.name)
+			}
+			for _, pt := range channel.points {
+				if math.IsNaN(pt.X) || math.IsNaN(pt.Y) || math.IsInf(pt.X, 0) || math.IsInf(pt.Y, 0) {
+					return fmt.Errorf("invalid curve preset point")
+				}
+				if pt.X < 0 || pt.X > 1 || pt.Y < 0 || pt.Y > 1 {
+					return fmt.Errorf("invalid curve preset point")
+				}
+			}
+		}
+		if _, dup := names[preset.Name]; dup {
+			return fmt.Errorf("duplicate curve preset name")
+		}
+		names[preset.Name] = struct{}{}
 	}
 	return nil
 }
@@ -230,18 +305,40 @@ func (h *Handler) UpdatePreferences(c *gin.Context) {
 		httpx.RespondError(c, httpx.BadRequest("invalid_preferences", "preferences must be a JSON object"))
 		return
 	}
+	payload.normalize()
 	if err := payload.validate(); err != nil {
 		httpx.RespondError(c, httpx.BadRequest("invalid_preferences", err.Error()))
 		return
 	}
-	raw, err := json.Marshal(payload)
+
+	ctx := c.Request.Context()
+	u, err := h.svc.store.GetUserByID(ctx, UserID(c))
 	if err != nil {
-		httpx.RespondError(c, httpx.BadRequest("invalid_preferences", "could not encode preferences"))
+		httpx.RespondError(c, httpx.Unauthorized("unauthorized", "user not found"))
 		return
 	}
-	if err := h.svc.store.UpdatePreferences(c.Request.Context(), UserID(c), raw); err != nil {
-		httpx.RespondError(c, err)
-		return
+	// Merge the submitted sections into the stored blob so saving one section
+	// never clears the others. Unknown keys are preserved.
+	merged := make(map[string]any, len(u.Preferences)+2)
+	for k, v := range u.Preferences {
+		merged[k] = v
 	}
-	c.JSON(http.StatusOK, gin.H{"preferences": payload})
+	if payload.PhotoInfo != nil {
+		merged["photo_info"] = payload.PhotoInfo
+	}
+	if payload.CurvePresets != nil {
+		merged["curve_presets"] = *payload.CurvePresets
+	}
+	if payload.PhotoInfo != nil || payload.CurvePresets != nil {
+		raw, err := json.Marshal(merged)
+		if err != nil {
+			httpx.RespondError(c, httpx.BadRequest("invalid_preferences", "could not encode preferences"))
+			return
+		}
+		if err := h.svc.store.UpdatePreferences(ctx, UserID(c), raw); err != nil {
+			httpx.RespondError(c, err)
+			return
+		}
+	}
+	c.JSON(http.StatusOK, gin.H{"preferences": merged})
 }