Add i18n support for French and German with browser language detection

meals.py

@@ -23,6 +23,7 @@ from models import (
     delete_household,
     count_household_users,
 )
+from i18n import t
 
 meals_bp = Blueprint("meals", __name__)
 
@@ -60,7 +61,7 @@ def dashboard():
         try:
             today = datetime.strptime(date_str, "%Y-%m-%d").date()
         except ValueError:
-            flash("Invalid date format. Use YYYY-MM-DD.", "error")
+            flash(t("Invalid date format. Use YYYY-MM-DD."), "error")
 
     if household_id is None:
         session.clear()
@@ -87,27 +88,27 @@ def respond():
     date_str = request.form.get("date", date.today().isoformat())
 
     if meal_type not in ("lunch", "dinner"):
-        flash("Invalid meal type.", "error")
+        flash(t("Invalid meal type."), "error")
         return redirect(url_for("meals.dashboard"))
 
     if status not in ("yes", "no"):
-        flash("Invalid status.", "error")
+        flash(t("Invalid status."), "error")
         return redirect(url_for("meals.dashboard"))
 
     try:
         target_date = datetime.strptime(date_str, "%Y-%m-%d").date()
     except ValueError:
-        flash("Invalid date.", "error")
+        flash(t("Invalid date."), "error")
         return redirect(url_for("meals.dashboard"))
 
     if target_date < date.today():
-        flash("Cannot change responses for past dates.", "error")
+        flash(t("Cannot change responses for past dates."), "error")
         return redirect(url_for("meals.dashboard"))
 
     periods = ensure_meal_periods(target_date)
     period = next((p for p in periods if p["meal_type"] == meal_type), None)
     if period is None:
-        flash("Meal period not found.", "error")
+        flash(t("Meal period not found."), "error")
         return redirect(url_for("meals.dashboard"))
 
     upsert_response(session["user_id"], period["id"], status)
@@ -147,7 +148,7 @@ def delete_account():
     user = get_user_by_id(session["user_id"])
 
     if not check_password_hash(user["password_hash"], password):
-        flash("Incorrect password. Account not deleted.", "error")
+        flash(t("Incorrect password. Account not deleted."), "error")
         return redirect(url_for("meals.dashboard"))
 
     household_id = session["household_id"]
@@ -157,10 +158,10 @@ def delete_account():
     # If admin is the last user, delete the household too
     if is_admin and user_count == 1:
         delete_household(household_id)
-        flash("Your account and household have been deleted.", "success")
+        flash(t("Your account and household have been deleted."), "success")
     else:
         delete_user(session["user_id"])
-        flash("Your account has been deleted.", "success")
+        flash(t("Your account has been deleted."), "success")
 
     # Clear auth keys but keep the session so flash survives the redirect
     for key in ("user_id", "username", "is_admin", "household_id", "household_name"):
@@ -173,20 +174,20 @@ def delete_account():
 def admin_remove_user(user_id):
     """Admin removes a user from the household."""
     if not session["is_admin"]:
-        flash("Only admins can remove users.", "error")
+        flash(t("Only admins can remove users."), "error")
         return redirect(url_for("meals.dashboard"))
 
     user = get_user_by_id(user_id)
     if user is None or user["household_id"] != session["household_id"]:
-        flash("User not found in your household.", "error")
+        flash(t("User not found in your household."), "error")
         return redirect(url_for("meals.dashboard"))
 
     if user["is_admin"]:
-        flash("Cannot remove the admin. Transfer admin role first or delete the household.", "error")
+        flash(t("Cannot remove the admin. Transfer admin role first or delete the household."), "error")
         return redirect(url_for("meals.dashboard"))
 
     delete_user(user_id)
-    flash(f"User '{user['username']}' has been removed.", "success")
+    flash(t("User '{name}' has been removed.", name=user["username"]), "success")
     return redirect(url_for("meals.dashboard"))
 
 
@@ -195,18 +196,18 @@ def admin_remove_user(user_id):
 def admin_delete_household():
     """Admin deletes the entire household."""
     if not session["is_admin"]:
-        flash("Only admins can delete the household.", "error")
+        flash(t("Only admins can delete the household."), "error")
         return redirect(url_for("meals.dashboard"))
 
     password = request.form.get("password", "")
     user = get_user_by_id(session["user_id"])
 
     if not check_password_hash(user["password_hash"], password):
-        flash("Incorrect password. Household not deleted.", "error")
+        flash(t("Incorrect password. Household not deleted."), "error")
         return redirect(url_for("meals.dashboard"))
 
     delete_household(session["household_id"])
-    flash("Household and all members have been deleted.", "success")
+    flash(t("Household and all members have been deleted."), "success")
     for key in ("user_id", "username", "is_admin", "household_id", "household_name"):
         session.pop(key, None)
     return redirect(url_for("auth.login"))