From 8ed9adeea0eb3e6d59a28f18ff2c1de4f499f4dd Mon Sep 17 00:00:00 2001
From: Moritz <moritz.m@local-it.org>
Date: Tue, 16 Dec 2025 11:59:39 +0100
Subject: [PATCH] fix: preserve form values when only interval field changes

- Merge existing form values with new params to prevent field loss
- Add get_existing_form_values helper to extract current form state
- Fixes issue where name and amount were cleared when selecting interval
---
 .../live/membership_fee_type_live/form.ex     | 71 ++++++++++++++++---
 1 file changed, 63 insertions(+), 8 deletions(-)

diff --git a/lib/mv_web/live/membership_fee_type_live/form.ex b/lib/mv_web/live/membership_fee_type_live/form.ex
index 96611c8..16a3b67 100644
--- a/lib/mv_web/live/membership_fee_type_live/form.ex
+++ b/lib/mv_web/live/membership_fee_type_live/form.ex
@@ -56,20 +56,35 @@ defmodule MvWeb.MembershipFeeTypeLive.Form do
           <select
             class="select select-bordered w-full"
             disabled={!is_nil(@membership_fee_type)}
-            name="interval"
-            value={@form[:interval].value || ""}
+            name="membership_fee_type[interval]"
+            id="membership-fee-type-form_interval"
+            phx-change="validate"
           >
             <option value="">{gettext("Select interval")}</option>
-            <option value="monthly" selected={@form[:interval].value == :monthly}>
+            <option
+              value="monthly"
+              selected={@form[:interval].value == :monthly || @form[:interval].value == "monthly"}
+            >
               {gettext("Monthly")}
             </option>
-            <option value="quarterly" selected={@form[:interval].value == :quarterly}>
+            <option
+              value="quarterly"
+              selected={@form[:interval].value == :quarterly || @form[:interval].value == "quarterly"}
+            >
               {gettext("Quarterly")}
             </option>
-            <option value="half_yearly" selected={@form[:interval].value == :half_yearly}>
+            <option
+              value="half_yearly"
+              selected={
+                @form[:interval].value == :half_yearly || @form[:interval].value == "half_yearly"
+              }
+            >
               {gettext("Half-yearly")}
             </option>
-            <option value="yearly" selected={@form[:interval].value == :yearly}>
+            <option
+              value="yearly"
+              selected={@form[:interval].value == :yearly || @form[:interval].value == "yearly"}
+            >
               {gettext("Yearly")}
             </option>
           </select>
@@ -192,10 +207,27 @@ defmodule MvWeb.MembershipFeeTypeLive.Form do
 
   @impl true
   def handle_event("validate", %{"membership_fee_type" => params}, socket) do
-    validated_form = AshPhoenix.Form.validate(socket.assigns.form, params)
+    # Merge with existing form values to preserve unchanged fields
+    existing_values = get_existing_form_values(socket.assigns.form)
+
+    # Merge existing values with new params (new params take precedence)
+    merged_params = Map.merge(existing_values, params)
+
+    # Convert interval string to atom if present
+    merged_params =
+      if Map.has_key?(merged_params, "interval") && is_binary(merged_params["interval"]) &&
+           merged_params["interval"] != "" do
+        Map.update!(merged_params, "interval", fn val ->
+          String.to_existing_atom(val)
+        end)
+      else
+        merged_params
+      end
+
+    validated_form = AshPhoenix.Form.validate(socket.assigns.form, merged_params)
 
     # Check if amount changed on edit
-    socket = check_amount_change(socket, params)
+    socket = check_amount_change(socket, merged_params)
 
     {:noreply, assign(socket, form: validated_form)}
   end
@@ -289,6 +321,29 @@ defmodule MvWeb.MembershipFeeTypeLive.Form do
     assign(socket, form: to_form(form))
   end
 
+  # Helper to extract existing form values to preserve them when only one field changes
+  defp get_existing_form_values(form) do
+    # Get current form values from the form source
+    case form.source.params do
+      %{"membership_fee_type" => existing_params} when is_map(existing_params) ->
+        # Convert atoms to strings for form params
+        existing_params
+        |> Enum.map(fn
+          {key, value} when is_atom(key) -> {Atom.to_string(key), value}
+          {key, value} -> {key, value}
+        end)
+        |> Enum.map(fn
+          {key, value} when is_atom(value) -> {key, Atom.to_string(value)}
+          {key, value} -> {key, value}
+        end)
+        |> Map.new()
+
+      _ ->
+        # No existing params, return empty map
+        %{}
+    end
+  end
+
   @spec return_path(String.t(), MembershipFeeType.t() | nil) :: String.t()
   defp return_path("index", _membership_fee_type), do: ~p"/membership_fee_types"