Fix amount change warning and form value preservation

Add phx-debounce to amount input and preserve form values on confirm

lib/mv_web/live/membership_fee_type_live/form.ex

@@ -44,6 +44,7 @@ defmodule MvWeb.MembershipFeeTypeLive.Form do
           field={@form[:amount]}
           label={gettext("Amount")}
           required
+          phx-debounce="blur"
         />
 
         <div class="form-control">
@@ -257,11 +258,15 @@ defmodule MvWeb.MembershipFeeTypeLive.Form do
 
   def handle_event("confirm_amount_change", _params, socket) do
     # Update form with pending amount and hide warning
+    # Preserve all existing form values (name, description, etc.)
     form = socket.assigns.form
+    existing_values = get_existing_form_values(form)
 
     updated_form =
       if socket.assigns.pending_amount do
-        AshPhoenix.Form.validate(form, %{"amount" => socket.assigns.pending_amount})
+        # Merge existing values with confirmed amount to preserve all fields
+        merged_params = Map.put(existing_values, "amount", socket.assigns.pending_amount)
+        AshPhoenix.Form.validate(form, merged_params)
       else
         form
       end
@@ -357,7 +362,20 @@ defmodule MvWeb.MembershipFeeTypeLive.Form do
   # Checks if amount changed and updates socket assigns accordingly
   defp check_amount_change(socket, params) do
     if socket.assigns.membership_fee_type && Map.has_key?(params, "amount") do
-      handle_amount_change(socket, params["amount"], socket.assigns.membership_fee_type.amount)
+      # Get current amount from form and new amount from params
+      current_form_amount = get_existing_form_values(socket.assigns.form)["amount"]
+      new_amount_str = params["amount"]
+
+      # Only check amount change if amount field is actually being changed in this validation
+      # This prevents re-triggering the warning when other fields (name, description) are edited
+      if current_form_amount != new_amount_str do
+        handle_amount_change(socket, new_amount_str, socket.assigns.membership_fee_type.amount)
+      else
+        # Amount didn't change in this validation - keep current warning state
+        # If warning was already confirmed (pending_amount is nil and show_amount_warning is false), keep it hidden
+        # If warning is shown but not confirmed, keep it shown
+        socket
+      end
     else
       socket
     end
@@ -379,8 +397,17 @@ defmodule MvWeb.MembershipFeeTypeLive.Form do
   end
 
   # Shows amount change warning with affected member count
+  # Only calculates count if warning is being shown for the first time (false -> true)
   defp show_amount_warning(socket, old_amount, new_amount, new_amount_str) do
-    affected_count = get_affected_member_count(socket.assigns.membership_fee_type.id)
+    # Only calculate count if warning is not already shown (optimization)
+    affected_count =
+      if socket.assigns.show_amount_warning do
+        # Warning already shown, reuse existing count
+        socket.assigns.affected_member_count
+      else
+        # Warning being shown for first time, calculate count
+        get_affected_member_count(socket.assigns.membership_fee_type.id)
+      end
 
     socket
     |> assign(:show_amount_warning, true)