Files
food-ai/backend/internal/user/calories.go
dbastrikin c9ddb708b1 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>
2026-03-09 23:37:58 +02:00

72 lines
1.5 KiB
Go

package user
import (
"math"
"time"
)
// Activity level multipliers (Mifflin-St Jeor).
var activityMultiplier = map[string]float64{
"low": 1.375,
"moderate": 1.55,
"high": 1.725,
}
// Goal adjustments in kcal.
var goalAdjustment = map[string]float64{
"lose": -500,
"maintain": 0,
"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 {
if heightCM == nil || weightKG == nil || age == nil || gender == nil || activity == nil || goal == nil {
return nil
}
// BMR = 10 * weight(kg) + 6.25 * height(cm) - 5 * age
bmr := 10**weightKG + 6.25*float64(*heightCM) - 5*float64(*age)
switch *gender {
case "male":
bmr += 5
case "female":
bmr -= 161
default:
return nil
}
mult, ok := activityMultiplier[*activity]
if !ok {
return nil
}
adj, ok := goalAdjustment[*goal]
if !ok {
return nil
}
tdee := bmr * mult
result := int(math.Round(tdee + adj))
return &result
}