feat: replace age integer with date_of_birth across backend and client

Store date_of_birth (DATE) instead of a static age integer so that age
is always computed dynamically from the stored date of birth.

- Migration 011: adds date_of_birth, backfills from age, drops age
- AgeFromDOB helper computes current age from YYYY-MM-DD string
- User model, repository SQL, and service validation updated
- Flutter: User.age becomes a computed getter; profile edit screen
  uses a date picker bounded to [today-120y, today-10y]

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

backend/internal/user/calories.go

@@ -1,6 +1,9 @@
 package user
 
-import "math"
+import (
+	"math"
+	"time"
+)
 
 // Activity level multipliers (Mifflin-St Jeor).
 var activityMultiplier = map[string]float64{
@@ -16,6 +19,23 @@ var goalAdjustment = map[string]float64{
 	"gain":     300,
 }
 
+// AgeFromDOB computes age in years from a "YYYY-MM-DD" string. Returns nil on error.
+func AgeFromDOB(dob *string) *int {
+	if dob == nil {
+		return nil
+	}
+	t, err := time.Parse("2006-01-02", *dob)
+	if err != nil {
+		return nil
+	}
+	now := time.Now()
+	years := now.Year() - t.Year()
+	if now.Month() < t.Month() || (now.Month() == t.Month() && now.Day() < t.Day()) {
+		years--
+	}
+	return &years
+}
+
 // CalculateDailyCalories computes the daily calorie target using the
 // Mifflin-St Jeor equation. Returns nil if any required parameter is missing.
 func CalculateDailyCalories(heightCM *int, weightKG *float64, age *int, gender, activity, goal *string) *int {

backend/internal/user/calories_test.go

@@ -2,10 +2,48 @@ package user
 
 import (
 	"testing"
+	"time"
 )
 
 func ptr[T any](v T) *T { return &v }
 
+func TestAgeFromDOB_Nil(t *testing.T) {
+	if AgeFromDOB(nil) != nil {
+		t.Fatal("expected nil for nil input")
+	}
+}
+
+func TestAgeFromDOB_InvalidFormat(t *testing.T) {
+	s := "not-a-date"
+	if AgeFromDOB(&s) != nil {
+		t.Fatal("expected nil for invalid format")
+	}
+}
+
+func TestAgeFromDOB_ExactAge(t *testing.T) {
+	dob := time.Now().AddDate(-30, 0, 0).Format("2006-01-02")
+	age := AgeFromDOB(&dob)
+	if age == nil {
+		t.Fatal("expected non-nil result")
+	}
+	if *age != 30 {
+		t.Errorf("expected 30, got %d", *age)
+	}
+}
+
+func TestAgeFromDOB_BeforeBirthday(t *testing.T) {
+	// Birthday is one day in the future relative to today-25y, so age should be 24
+	now := time.Now()
+	dob := time.Date(now.Year()-25, now.Month(), now.Day()+1, 0, 0, 0, 0, time.UTC).Format("2006-01-02")
+	age := AgeFromDOB(&dob)
+	if age == nil {
+		t.Fatal("expected non-nil result")
+	}
+	if *age != 24 {
+		t.Errorf("expected 24, got %d", *age)
+	}
+}
+
 func TestCalculateDailyCalories_MaleMaintain(t *testing.T) {
 	cal := CalculateDailyCalories(ptr(180), ptr(80.0), ptr(30), ptr("male"), ptr("moderate"), ptr("maintain"))
 	if cal == nil {

backend/internal/user/model.go

@@ -13,7 +13,7 @@ type User struct {
 	AvatarURL     *string         `json:"avatar_url"`
 	HeightCM      *int            `json:"height_cm"`
 	WeightKG      *float64        `json:"weight_kg"`
-	Age           *int            `json:"age"`
+	DateOfBirth   *string         `json:"date_of_birth"`
 	Gender        *string         `json:"gender"`
 	Activity      *string         `json:"activity"`
 	Goal          *string         `json:"goal"`
@@ -28,7 +28,7 @@ type UpdateProfileRequest struct {
 	Name          *string          `json:"name"`
 	HeightCM      *int             `json:"height_cm"`
 	WeightKG      *float64         `json:"weight_kg"`
-	Age           *int             `json:"age"`
+	DateOfBirth   *string          `json:"date_of_birth"`
 	Gender        *string          `json:"gender"`
 	Activity      *string          `json:"activity"`
 	Goal          *string          `json:"goal"`
@@ -39,6 +39,6 @@ type UpdateProfileRequest struct {
 // HasBodyParams returns true if any body parameter is being updated
 // that would require recalculation of daily calories.
 func (r *UpdateProfileRequest) HasBodyParams() bool {
-	return r.HeightCM != nil || r.WeightKG != nil || r.Age != nil ||
+	return r.HeightCM != nil || r.WeightKG != nil || r.DateOfBirth != nil ||
 		r.Gender != nil || r.Activity != nil || r.Goal != nil
 }

backend/internal/user/repository.go

@@ -45,7 +45,7 @@ func (r *Repository) UpsertByFirebaseUID(ctx context.Context, uid, email, name,
 			avatar_url = COALESCE(EXCLUDED.avatar_url, users.avatar_url),
 			updated_at = now()
 		RETURNING id, firebase_uid, email, name, avatar_url,
-			height_cm, weight_kg, age, gender, activity, goal, daily_calories,
+			height_cm, weight_kg, date_of_birth, gender, activity, goal, daily_calories,
 			plan, preferences, created_at, updated_at`
 
 	return r.scanUser(r.pool.QueryRow(ctx, query, uid, email, name, avatarPtr))
@@ -54,7 +54,7 @@ func (r *Repository) UpsertByFirebaseUID(ctx context.Context, uid, email, name,
 func (r *Repository) GetByID(ctx context.Context, id string) (*User, error) {
 	query := `
 		SELECT id, firebase_uid, email, name, avatar_url,
-			height_cm, weight_kg, age, gender, activity, goal, daily_calories,
+			height_cm, weight_kg, date_of_birth, gender, activity, goal, daily_calories,
 			plan, preferences, created_at, updated_at
 		FROM users WHERE id = $1`
 
@@ -91,9 +91,9 @@ func buildUpdateQuery(id string, req UpdateProfileRequest) (string, []interface{
 		args = append(args, *req.WeightKG)
 		argIdx++
 	}
-	if req.Age != nil {
+	if req.DateOfBirth != nil {
-		setClauses = append(setClauses, fmt.Sprintf("age = $%d", argIdx))
+		setClauses = append(setClauses, fmt.Sprintf("date_of_birth = $%d", argIdx))
-		args = append(args, *req.Age)
+		args = append(args, *req.DateOfBirth)
 		argIdx++
 	}
 	if req.Gender != nil {
@@ -132,7 +132,7 @@ func buildUpdateQuery(id string, req UpdateProfileRequest) (string, []interface{
 		UPDATE users SET %s
 		WHERE id = $%d
 		RETURNING id, firebase_uid, email, name, avatar_url,
-			height_cm, weight_kg, age, gender, activity, goal, daily_calories,
+			height_cm, weight_kg, date_of_birth, gender, activity, goal, daily_calories,
 			plan, preferences, created_at, updated_at`,
 		strings.Join(setClauses, ", "), argIdx)
 	args = append(args, id)
@@ -184,7 +184,7 @@ func (r *Repository) SetRefreshToken(ctx context.Context, id, token string, expi
 func (r *Repository) FindByRefreshToken(ctx context.Context, token string) (*User, error) {
 	query := `
 		SELECT id, firebase_uid, email, name, avatar_url,
-			height_cm, weight_kg, age, gender, activity, goal, daily_calories,
+			height_cm, weight_kg, date_of_birth, gender, activity, goal, daily_calories,
 			plan, preferences, created_at, updated_at
 		FROM users
 		WHERE refresh_token = $1 AND token_expires_at > now()`
@@ -205,14 +205,19 @@ type scannable interface {
 func (r *Repository) scanUser(row scannable) (*User, error) {
 	var u User
 	var prefs []byte
+	var dob *time.Time
 	err := row.Scan(
 		&u.ID, &u.FirebaseUID, &u.Email, &u.Name, &u.AvatarURL,
-		&u.HeightCM, &u.WeightKG, &u.Age, &u.Gender, &u.Activity, &u.Goal, &u.DailyCalories,
+		&u.HeightCM, &u.WeightKG, &dob, &u.Gender, &u.Activity, &u.Goal, &u.DailyCalories,
 		&u.Plan, &prefs, &u.CreatedAt, &u.UpdatedAt,
 	)
 	if err != nil {
 		return nil, fmt.Errorf("scan user: %w", err)
 	}
+	if dob != nil {
+		s := dob.Format("2006-01-02")
+		u.DateOfBirth = &s
+	}
 	u.Preferences = json.RawMessage(prefs)
 	return &u, nil
 }

backend/internal/user/repository_integration_test.go

@@ -100,17 +100,17 @@ func TestRepository_Update_MultipleFields(t *testing.T) {
 	created, _ := repo.UpsertByFirebaseUID(ctx, "fb-multi", "multi@example.com", "Multi User", "")
 	height := 175
 	weight := 70.5
-	age := 25
+	dob := "2001-03-09"
 	gender := "male"
 	activity := "moderate"
 	goal := "maintain"
 	u, err := repo.Update(ctx, created.ID, UpdateProfileRequest{
-		HeightCM: &height,
+		HeightCM:    &height,
-		WeightKG: &weight,
+		WeightKG:    &weight,
-		Age:      &age,
+		DateOfBirth: &dob,
-		Gender:   &gender,
+		Gender:      &gender,
-		Activity: &activity,
+		Activity:    &activity,
-		Goal:     &goal,
+		Goal:        &goal,
 	})
 	if err != nil {
 		t.Fatalf("unexpected error: %v", err)

backend/internal/user/service.go

@@ -3,6 +3,7 @@ package user
 import (
 	"context"
 	"fmt"
+	"time"
 )
 
 type Service struct {
@@ -46,10 +47,11 @@ func (s *Service) UpdateProfile(ctx context.Context, userID string, req UpdatePr
 	if req.WeightKG != nil {
 		weight = req.WeightKG
 	}
-	age := current.Age
+	dob := current.DateOfBirth
-	if req.Age != nil {
+	if req.DateOfBirth != nil {
-		age = req.Age
+		dob = req.DateOfBirth
 	}
+	age := AgeFromDOB(dob)
 	gender := current.Gender
 	if req.Gender != nil {
 		gender = req.Gender
@@ -89,9 +91,17 @@ func validateProfileRequest(req UpdateProfileRequest) error {
 			return fmt.Errorf("weight_kg must be between 30 and 300")
 		}
 	}
-	if req.Age != nil {
+	if req.DateOfBirth != nil {
-		if *req.Age < 10 || *req.Age > 120 {
+		t, err := time.Parse("2006-01-02", *req.DateOfBirth)
-			return fmt.Errorf("age must be between 10 and 120")
+		if err != nil {
+			return fmt.Errorf("date_of_birth must be in YYYY-MM-DD format")
+		}
+		if t.After(time.Now()) {
+			return fmt.Errorf("date_of_birth cannot be in the future")
+		}
+		age := AgeFromDOB(req.DateOfBirth)
+		if *age < 10 || *age > 120 {
+			return fmt.Errorf("date_of_birth must yield an age between 10 and 120")
 		}
 	}
 	if req.Gender != nil {

backend/internal/user/service_test.go

@@ -94,19 +94,20 @@ func TestUpdateProfile_NameOnly(t *testing.T) {
 }
 
 func TestUpdateProfile_WithCaloriesRecalculation(t *testing.T) {
+	dob := time.Now().AddDate(-30, 0, 0).Format("2006-01-02")
 	profileReq := UpdateProfileRequest{
-		HeightCM: ptrInt(180),
+		HeightCM:    ptrInt(180),
-		WeightKG: ptrFloat(80),
+		WeightKG:    ptrFloat(80),
-		Age:      ptrInt(30),
+		DateOfBirth: &dob,
-		Gender:   ptrStr("male"),
+		Gender:      ptrStr("male"),
-		Activity: ptrStr("moderate"),
+		Activity:    ptrStr("moderate"),
-		Goal:     ptrStr("maintain"),
+		Goal:        ptrStr("maintain"),
 	}
 	finalUser := &User{
 		ID:            "user-1",
 		HeightCM:      ptrInt(180),
 		WeightKG:      ptrFloat(80),
-		Age:           ptrInt(30),
+		DateOfBirth:   &dob,
 		Gender:        ptrStr("male"),
 		Activity:      ptrStr("moderate"),
 		Goal:          ptrStr("maintain"),
@@ -178,19 +179,31 @@ func TestUpdateProfile_InvalidWeight_TooHigh(t *testing.T) {
 	}
 }
 
-func TestUpdateProfile_InvalidAge_TooLow(t *testing.T) {
+func TestUpdateProfile_InvalidDOB_TooRecent(t *testing.T) {
 	svc := NewService(&mockUserRepo{})
+	dob := time.Now().AddDate(-5, 0, 0).Format("2006-01-02")
 
-	_, err := svc.UpdateProfile(context.Background(), "user-1", UpdateProfileRequest{Age: ptrInt(5)})
+	_, err := svc.UpdateProfile(context.Background(), "user-1", UpdateProfileRequest{DateOfBirth: &dob})
 	if err == nil {
 		t.Fatal("expected validation error")
 	}
 }
 
-func TestUpdateProfile_InvalidAge_TooHigh(t *testing.T) {
+func TestUpdateProfile_InvalidDOB_TooOld(t *testing.T) {
 	svc := NewService(&mockUserRepo{})
+	dob := time.Now().AddDate(-150, 0, 0).Format("2006-01-02")
 
-	_, err := svc.UpdateProfile(context.Background(), "user-1", UpdateProfileRequest{Age: ptrInt(150)})
+	_, err := svc.UpdateProfile(context.Background(), "user-1", UpdateProfileRequest{DateOfBirth: &dob})
+	if err == nil {
+		t.Fatal("expected validation error")
+	}
+}
+
+func TestUpdateProfile_InvalidDOB_BadFormat(t *testing.T) {
+	svc := NewService(&mockUserRepo{})
+	dob := "not-a-date"
+
+	_, err := svc.UpdateProfile(context.Background(), "user-1", UpdateProfileRequest{DateOfBirth: &dob})
 	if err == nil {
 		t.Fatal("expected validation error")
 	}

backend/migrations/011_replace_age_with_date_of_birth.sql

@@ -0,0 +1,13 @@
+-- +goose Up
+ALTER TABLE users ADD COLUMN date_of_birth DATE;
+UPDATE users
+    SET date_of_birth = (CURRENT_DATE - (age * INTERVAL '1 year'))::DATE
+    WHERE age IS NOT NULL;
+ALTER TABLE users DROP COLUMN age;
+
+-- +goose Down
+ALTER TABLE users ADD COLUMN age SMALLINT;
+UPDATE users
+    SET age = EXTRACT(YEAR FROM AGE(CURRENT_DATE, date_of_birth))::SMALLINT
+    WHERE date_of_birth IS NOT NULL;
+ALTER TABLE users DROP COLUMN date_of_birth;

client/lib/features/profile/profile_screen.dart

@@ -336,7 +336,7 @@ class _EditProfileSheetState extends ConsumerState<EditProfileSheet> {
   late final TextEditingController _nameCtrl;
   late final TextEditingController _heightCtrl;
   late final TextEditingController _weightCtrl;
-  late final TextEditingController _ageCtrl;
+  DateTime? _selectedDob;
   String? _gender;
   String? _goal;
   String? _activity;
@@ -351,7 +351,8 @@ class _EditProfileSheetState extends ConsumerState<EditProfileSheet> {
     _heightCtrl = TextEditingController(text: u.heightCm?.toString() ?? '');
     _weightCtrl = TextEditingController(
         text: u.weightKg != null ? _fmt(u.weightKg!) : '');
-    _ageCtrl = TextEditingController(text: u.age?.toString() ?? '');
+    _selectedDob =
+        u.dateOfBirth != null ? DateTime.tryParse(u.dateOfBirth!) : null;
     _gender = u.gender;
     _goal = u.goal;
     _activity = u.activity;
@@ -363,13 +364,24 @@ class _EditProfileSheetState extends ConsumerState<EditProfileSheet> {
     _nameCtrl.dispose();
     _heightCtrl.dispose();
     _weightCtrl.dispose();
-    _ageCtrl.dispose();
     super.dispose();
   }
 
   String _fmt(double w) =>
       w == w.truncateToDouble() ? w.toInt().toString() : w.toStringAsFixed(1);
 
+  Future<void> _pickDob() async {
+    final now = DateTime.now();
+    final initial = _selectedDob ?? DateTime(now.year - 25, now.month, now.day);
+    final picked = await showDatePicker(
+      context: context,
+      initialDate: initial,
+      firstDate: DateTime(now.year - 120),
+      lastDate: DateTime(now.year - 10, now.month, now.day),
+    );
+    if (picked != null) setState(() => _selectedDob = picked);
+  }
+
   Future<void> _save() async {
     if (!_formKey.currentState!.validate()) return;
     setState(() => _saving = true);
@@ -378,7 +390,11 @@ class _EditProfileSheetState extends ConsumerState<EditProfileSheet> {
       name: _nameCtrl.text.trim(),
       heightCm: int.tryParse(_heightCtrl.text),
       weightKg: double.tryParse(_weightCtrl.text),
-      age: int.tryParse(_ageCtrl.text),
+      dateOfBirth: _selectedDob != null
+          ? '${_selectedDob!.year.toString().padLeft(4, '0')}-'
+              '${_selectedDob!.month.toString().padLeft(2, '0')}-'
+              '${_selectedDob!.day.toString().padLeft(2, '0')}'
+          : null,
       gender: _gender,
       goal: _goal,
       activity: _activity,
@@ -506,21 +522,21 @@ class _EditProfileSheetState extends ConsumerState<EditProfileSheet> {
                     ),
                     const SizedBox(height: 12),
 
-                    // Age
+                    // Date of birth
-                    TextFormField(
+                    InkWell(
-                      controller: _ageCtrl,
+                      onTap: _pickDob,
-                      decoration:
+                      child: InputDecorator(
-                          const InputDecoration(labelText: 'Возраст (лет)'),
+                        decoration:
-                      keyboardType: TextInputType.number,
+                            const InputDecoration(labelText: 'Дата рождения'),
-                      inputFormatters: [
+                        child: Text(
-                        FilteringTextInputFormatter.digitsOnly
+                          _selectedDob != null
-                      ],
+                              ? '${_selectedDob!.day.toString().padLeft(2, '0')}.'
-                      validator: (v) {
+                                  '${_selectedDob!.month.toString().padLeft(2, '0')}.'
-                        if (v == null || v.isEmpty) return null;
+                                  '${_selectedDob!.year}'
-                        final n = int.tryParse(v);
+                              : 'Не задано',
-                        if (n == null || n < 10 || n > 120) return '10–120';
+                          style: Theme.of(context).textTheme.bodyMedium,
-                        return null;
+                        ),
-                      },
+                      ),
                     ),
                     const SizedBox(height: 20),
 

client/lib/features/profile/profile_service.dart

@@ -12,7 +12,7 @@ class UpdateProfileRequest {
   final String? name;
   final int? heightCm;
   final double? weightKg;
-  final int? age;
+  final String? dateOfBirth;
   final String? gender;
   final String? activity;
   final String? goal;
@@ -22,7 +22,7 @@ class UpdateProfileRequest {
     this.name,
     this.heightCm,
     this.weightKg,
-    this.age,
+    this.dateOfBirth,
     this.gender,
     this.activity,
     this.goal,
@@ -34,7 +34,7 @@ class UpdateProfileRequest {
     if (name != null) map['name'] = name;
     if (heightCm != null) map['height_cm'] = heightCm;
     if (weightKg != null) map['weight_kg'] = weightKg;
-    if (age != null) map['age'] = age;
+    if (dateOfBirth != null) map['date_of_birth'] = dateOfBirth;
     if (gender != null) map['gender'] = gender;
     if (activity != null) map['activity'] = activity;
     if (goal != null) map['goal'] = goal;

client/lib/shared/models/user.dart

@@ -13,7 +13,8 @@ class User {
   final int? heightCm;
   @JsonKey(name: 'weight_kg')
   final double? weightKg;
-  final int? age;
+  @JsonKey(name: 'date_of_birth')
+  final String? dateOfBirth;
   final String? gender;
   final String? activity;
   final String? goal;
@@ -30,7 +31,7 @@ class User {
     this.avatarUrl,
     this.heightCm,
     this.weightKg,
-    this.age,
+    this.dateOfBirth,
     this.gender,
     this.activity,
     this.goal,
@@ -42,6 +43,19 @@ class User {
   factory User.fromJson(Map<String, dynamic> json) => _$UserFromJson(json);
   Map<String, dynamic> toJson() => _$UserToJson(this);
 
+  int? get age {
+    if (dateOfBirth == null) return null;
+    final dob = DateTime.tryParse(dateOfBirth!);
+    if (dob == null) return null;
+    final now = DateTime.now();
+    int years = now.year - dob.year;
+    if (now.month < dob.month ||
+        (now.month == dob.month && now.day < dob.day)) {
+      years--;
+    }
+    return years;
+  }
+
   bool get hasCompletedOnboarding =>
-      heightCm != null && weightKg != null && age != null && gender != null;
+      heightCm != null && weightKg != null && dateOfBirth != null && gender != null;
 }

client/lib/shared/models/user.g.dart

@@ -13,7 +13,7 @@ User _$UserFromJson(Map<String, dynamic> json) => User(
   avatarUrl: json['avatar_url'] as String?,
   heightCm: (json['height_cm'] as num?)?.toInt(),
   weightKg: (json['weight_kg'] as num?)?.toDouble(),
-  age: (json['age'] as num?)?.toInt(),
+  dateOfBirth: json['date_of_birth'] as String?,
   gender: json['gender'] as String?,
   activity: json['activity'] as String?,
   goal: json['goal'] as String?,
@@ -29,7 +29,7 @@ Map<String, dynamic> _$UserToJson(User instance) => <String, dynamic>{
   'avatar_url': instance.avatarUrl,
   'height_cm': instance.heightCm,
   'weight_kg': instance.weightKg,
-  'age': instance.age,
+  'date_of_birth': instance.dateOfBirth,
   'gender': instance.gender,
   'activity': instance.activity,
   'goal': instance.goal,

client/pubspec.lock

@@ -125,10 +125,10 @@ packages:
     dependency: transitive
     description:
       name: characters
-      sha256: faf38497bda5ead2a8c7615f4f7939df04333478bf32e4173fcb06d428b5716b
+      sha256: f71061c654a3380576a52b451dd5532377954cf9dbd272a78fc8479606670803
       url: "https://pub.dev"
     source: hosted
-    version: "1.4.1"
+    version: "1.4.0"
   checked_yaml:
     dependency: transitive
     description:
@@ -668,26 +668,26 @@ packages:
     dependency: transitive
     description:
       name: matcher
-      sha256: dc0b7dc7651697ea4ff3e69ef44b0407ea32c487a39fff6a4004fa585e901861
+      sha256: dc58c723c3c24bf8d3e2d3ad3f2f9d7bd9cf43ec6feaa64181775e60190153f2
       url: "https://pub.dev"
     source: hosted
-    version: "0.12.19"
+    version: "0.12.17"
   material_color_utilities:
     dependency: transitive
     description:
       name: material_color_utilities
-      sha256: "9c337007e82b1889149c82ed242ed1cb24a66044e30979c44912381e9be4c48b"
+      sha256: f7142bb1154231d7ea5f96bc7bde4bda2a0945d2806bb11670e30b850d56bdec
       url: "https://pub.dev"
     source: hosted
-    version: "0.13.0"
+    version: "0.11.1"
   meta:
     dependency: transitive
     description:
       name: meta
-      sha256: "23f08335362185a5ea2ad3a4e597f1375e78bce8a040df5c600c8d3552ef2394"
+      sha256: e3641ec5d63ebf0d9b41bd43201a66e3fc79a65db5f61fc181f04cd27aab950c
       url: "https://pub.dev"
     source: hosted
-    version: "1.17.0"
+    version: "1.16.0"
   mime:
     dependency: transitive
     description:
@@ -993,10 +993,10 @@ packages:
     dependency: transitive
     description:
       name: test_api
-      sha256: "8161c84903fd860b26bfdefb7963b3f0b68fee7adea0f59ef805ecca346f0c7a"
+      sha256: "522f00f556e73044315fa4585ec3270f1808a4b186c936e612cab0b565ff1e00"
       url: "https://pub.dev"
     source: hosted
-    version: "0.7.10"
+    version: "0.7.6"
   typed_data:
     dependency: transitive
     description: