Fix decimal truncation & stock display precision (#20)

* fix(dev): resolve SELinux volume mount permissions for PostgreSQL and MinIO containers

* fix(inventory): correct comma parsing and gram rounding errors

Fix two inventory bugs where commas were truncated in decimal
quantities and grams displayed with incorrect rounding.

Added unit tests to prevent regressions.

Author: serverplumber

lib/craftplan/types/unit.ex

@@ -128,5 +128,11 @@ defmodule Craftplan.Types.Unit do
   # Helper function to format numbers nicely
   defp format_number(value) when is_integer(value), do: "#{value}"
   defp format_number(value) when value == trunc(value), do: "#{trunc(value)}"
-  defp format_number(value), do: :erlang.float_to_binary(value, decimals: 1)
+
+  defp format_number(value) do
+    value
+    |> :erlang.float_to_binary(decimals: 3)
+    |> String.trim_trailing("0")
+    |> String.trim_trailing(".")
+  end
 end

lib/craftplan_web/live/manage/inventory_live/form_component_movement.ex

@@ -4,215 +4,171 @@ defmodule CraftplanWeb.InventoryLive.FormComponentMovement do
 
   alias AshPhoenix.Form
   alias Craftplan.Inventory
+  alias Decimal, as: D
+
+  @impl true
+  def update(assigns, socket) do
+    {:ok,
+     socket
+     |> assign(assigns)
+     |> assign_new(:mode, fn -> :add end)
+     |> assign_new(:calculated_new_total, fn -> nil end)
+     |> assign_new(:form, fn -> build_form(assigns.current_user) end)}
+  end
 
   @impl true
   def render(assigns) do
     ~H"""
     <div>
       <.simple_form
         for={@form}
-        id="movement-movment-form"
+        id="movement-form"
         phx-target={@myself}
         phx-change="validate"
         phx-submit="save"
       >
         <div class="mb-4">
-          <div class="mb-2">
-            <div class="flex items-center">
-              <button
-                type="button"
-                phx-click="toggle_adjustment_type"
-                phx-value-type="set_total"
-                phx-target={@myself}
-                class={[
-                  @adjustment_type == "set_total" && "bg-stone-200 text-stone-800",
-                  @adjustment_type != "set_total" && "bg-stone-50 text-stone-700 hover:bg-stone-100",
-                  "flex cursor-pointer items-center rounded-l-md border-y border-l border-stone-300 px-3 py-1 text-xs font-medium disabled:cursor-default disabled:bg-stone-100 disabled:text-stone-400"
-                ]}
-              >
-                Set Total
-              </button>
-              <button
-                type="button"
-                phx-click="toggle_adjustment_type"
-                phx-value-type="add"
-                phx-target={@myself}
-                class={[
-                  @adjustment_type == "add" && "bg-stone-200 text-stone-800",
-                  @adjustment_type != "add" && "bg-stone-50 text-stone-700 hover:bg-stone-100",
-                  "flex cursor-pointer items-center border-y border-stone-300 px-3 py-1 text-xs font-medium disabled:cursor-default disabled:bg-stone-100 disabled:text-stone-400"
-                ]}
-              >
-                Add
-              </button>
-              <button
-                type="button"
-                phx-click="toggle_adjustment_type"
-                phx-value-type="subtract"
-                phx-target={@myself}
-                class={[
-                  @adjustment_type == "subtract" && "bg-stone-200 text-stone-800",
-                  @adjustment_type != "subtract" && "bg-stone-50 text-stone-700 hover:bg-stone-100",
-                  "flex cursor-pointer items-center rounded-r-md border-y border-r border-stone-300 px-3 py-1 text-xs font-medium disabled:cursor-default disabled:bg-stone-100 disabled:text-stone-400"
-                ]}
-              >
-                Subtract
-              </button>
-            </div>
+          <div class="inline-flex rounded-md border border-stone-300">
+            <button
+              type="button"
+              phx-click="set_mode"
+              phx-value-mode="add"
+              phx-target={@myself}
+              class={[
+                "rounded-l-md px-4 py-1.5 text-xs font-medium transition-colors",
+                @mode == :add && "bg-stone-800 text-white",
+                @mode != :add && "bg-white text-stone-600 hover:bg-stone-50"
+              ]}
+            >
+              Add
+            </button>
+            <button
+              type="button"
+              phx-click="set_mode"
+              phx-value-mode="subtract"
+              phx-target={@myself}
+              class={[
+                "rounded-r-md border-l border-stone-300 px-4 py-1.5 text-xs font-medium transition-colors",
+                @mode == :subtract && "bg-stone-800 text-white",
+                @mode != :subtract && "bg-white text-stone-600 hover:bg-stone-50"
+              ]}
+            >
+              Subtract
+            </button>
           </div>
         </div>
 
-        <div :if={@adjustment_type == "add" || @adjustment_type == "subtract"}>
-          <.focus_wrap id="adjustment_quantity_focus_wrap">
-            <.input
-              field={@form[:quantity]}
-              type="number"
-              min="0"
-              label="Quantity"
-              inline_label={@material.unit}
-              phx-change="validate"
-              id="adjustment_quantity"
-            />
-          </.focus_wrap>
-          <.input field={@form[:operation]} type="hidden" value={@adjustment_type} />
-        </div>
-
-        <div :if={@adjustment_type == "set_total"}>
-          <.input
-            field={@form[:quantity]}
-            type="number"
-            min="0"
-            label="New Total"
-            inline_label={@material.unit}
-            phx-change="validate"
-          />
-        </div>
+        <.input
+          field={@form[:quantity]}
+          type="number"
+          min="0"
+          step="any"
+          label={if @mode == :add, do: "Quantity to add", else: "Quantity to subtract"}
+          inline_label={@material.unit}
+          id="movement-quantity"
+        />
 
         <.input field={@form[:reason]} type="textarea" label="Notes" class="mt-3" />
         <.input field={@form[:material_id]} type="hidden" value={@material.id} />
 
-        <div class="mt-4 rounded-md border border-stone-200 bg-stone-50 p-3 text-stone-700">
-          <div class="text-sm">
-            <span :if={is_number(@calculated_new_total)}>
-              <span class="font-medium">New stock will be:</span>
-              <span class="font-bold text-stone-900">
-                {format_amount(@material.unit, @calculated_new_total)}
-              </span>
-            </span>
-            <span :if={!is_number(@calculated_new_total)}>
-              Enter a quantity to see the new stock level
+        <div class="mt-4 rounded-md border border-stone-200 bg-stone-50 p-3 text-sm text-stone-700">
+          <%= if @calculated_new_total do %>
+            <span class="font-medium">New stock will be: </span>
+            <span class={[
+              "font-bold",
+              negative?(@calculated_new_total) && "text-red-600",
+              !negative?(@calculated_new_total) && "text-stone-900"
+            ]}>
+              {format_preview(@material.unit, @calculated_new_total)}
             </span>
-          </div>
+          <% else %>
+            Enter a quantity to see the new stock level
+          <% end %>
         </div>
 
         <:actions>
-          <.button variant={:primary} phx-disable-with="Saving...">
-            Save
-          </.button>
+          <.button variant={:primary} phx-disable-with="Saving...">Save</.button>
         </:actions>
       </.simple_form>
     </div>
     """
   end
 
   @impl true
-  def update(assigns, socket) do
-    {:ok,
-     socket
-     |> assign(assigns)
-     |> assign(adjustment_type: "set_total")
-     |> assign(:calculated_new_total, nil)
-     |> assign_form()}
-  end
+  def handle_event("set_mode", %{"mode" => mode}, socket) do
+    mode = String.to_existing_atom(mode)
+    quantity = parse_quantity(socket.assigns.form.params["quantity"])
+    current_stock = socket.assigns.material.current_stock
 
-  @impl true
-  def handle_event("toggle_adjustment_type", %{"type" => adjustment_type}, socket) do
-    quantity = parse_integer(socket.assigns.form.params["quantity"])
-    calculated_new_total = calculate_new_total(socket, adjustment_type, quantity)
-
-    {:noreply, assign(socket, adjustment_type: adjustment_type, calculated_new_total: calculated_new_total)}
+    {:noreply,
+     socket
+     |> assign(:mode, mode)
+     |> assign(:calculated_new_total, new_total(current_stock, mode, quantity))}
   end
 
   @impl true
-  def handle_event("validate", %{"movement" => movement_params}, socket) do
-    quantity = parse_integer(movement_params["quantity"])
-    calculated_new_total = calculate_new_total(socket, socket.assigns.adjustment_type, quantity)
+  def handle_event("validate", %{"movement" => params}, socket) do
+    quantity = parse_quantity(params["quantity"])
+    current_stock = socket.assigns.material.current_stock
 
     {:noreply,
      socket
-     |> assign(form: Form.validate(socket.assigns.form, movement_params))
-     |> assign(:calculated_new_total, calculated_new_total)}
+     |> assign(:form, Form.validate(socket.assigns.form, params))
+     |> assign(:calculated_new_total, new_total(current_stock, socket.assigns.mode, quantity))}
   end
 
-  def handle_event("save", %{"movement" => movement_params}, socket) do
-    movement_params = prepare_movement_params(movement_params, socket.assigns.adjustment_type)
+  @impl true
+  def handle_event("save", %{"movement" => params}, socket) do
+    params = sign_quantity(params, socket.assigns.mode)
 
-    case Form.submit(socket.assigns.form, params: movement_params) do
+    case Form.submit(socket.assigns.form, params: params) do
       {:ok, movement} ->
         send(self(), {:saved, movement})
 
         {:noreply,
          socket
-         |> put_flash(:info, "Material #{socket.assigns.form.source.type}d successfully")
+         |> put_flash(:info, "Stock adjustment recorded")
          |> push_patch(to: socket.assigns.patch)}
 
       {:error, form} ->
         {:noreply, assign(socket, :form, form)}
     end
   end
 
-  defp calculate_new_total(socket, adjustment_type, quantity) do
-    current_quantity = socket.assigns.material.current_stock
-
-    case adjustment_type do
-      "add" ->
-        if is_integer(quantity) do
-          result = Decimal.add(current_quantity, quantity)
-          Decimal.to_float(result)
-        end
-
-      "subtract" ->
-        if is_integer(quantity) do
-          result = Decimal.sub(current_quantity, quantity)
-          result = if Decimal.compare(result, 0) == :lt, do: Decimal.new(0), else: result
-          Decimal.to_float(result)
-        end
-
-      "set_total" ->
-        if is_integer(quantity), do: quantity * 1.0
+  defp new_total(_current_stock, _mode, nil), do: nil
+  defp new_total(current_stock, :add, quantity), do: D.add(current_stock, quantity)
+  defp new_total(current_stock, :subtract, quantity), do: D.sub(current_stock, quantity)
+
+  defp sign_quantity(params, :subtract) do
+    case parse_quantity(params["quantity"]) do
+      nil -> params
+      qty -> Map.put(params, "quantity", D.to_string(D.negate(qty)))
     end
   end
 
-  defp prepare_movement_params(params, adjustment_type) when adjustment_type in ["add", "subtract"] do
-    quantity = String.to_integer(params["quantity"] || "0")
-
-    quantity =
-      case adjustment_type do
-        "subtract" -> -quantity
-        _ -> quantity
-      end
+  defp sign_quantity(params, :add), do: params
 
-    Map.put(params, "quantity", to_string(quantity))
+  defp parse_quantity(value) when is_binary(value) and value != "" do
+    case D.parse(value) do
+      {d, ""} -> d
+      _ -> nil
+    end
   end
 
-  defp prepare_movement_params(params, _), do: params
+  defp parse_quantity(_), do: nil
 
-  defp assign_form(socket) do
-    form =
-      Form.for_create(Inventory.Movement, :adjust_stock,
-        as: "movement",
-        actor: socket.assigns.current_user
-      )
+  defp negative?(value), do: D.compare(value, D.new(0)) == :lt
 
-    assign(socket, form: to_form(form))
+  defp format_preview(unit, %D{} = value) do
+    format_amount(unit, D.to_float(value))
   end
 
-  defp parse_integer(value) when is_binary(value) do
-    case Integer.parse(value) do
-      {int, _} -> int
-      :error -> nil
-    end
+  defp build_form(current_user) do
+    Inventory.Movement
+    |> Form.for_create(:adjust_stock,
+      as: "movement",
+      actor: current_user
+    )
+    |> to_form()
   end
-
-  defp parse_integer(_), do: nil
 end