feat(expenses,groups): add linkage between expenses and groups

CLAUDE.md

@@ -135,3 +135,5 @@ Use the following principles when making changes to this project:
 1. Prioritize pheonix framework code generators over coding from scratch. Utilize these tools to bootstrap the core domain models and structure of the app. You should not be creating too much custom code except within the concrete implementation of services that the generators have bootstrapped.
 
 2. When working on front end code, make sure that every new component or UI change conforms do the existing design language. Prioritize reusability instead of customizing every individual piece.
+
+3. After making any new feature change, add any relevant tests in and make sure that all tests pass.

lib/split_app/expenses.ex

@@ -87,6 +87,44 @@ defmodule SplitApp.Expenses do
     |> Repo.insert()
   end
 
+  @doc """
+  Creates an expense with associated groups.
+
+  ## Examples
+
+      iex> create_expense_with_groups(%{field: value}, [1, 2])
+      {:ok, %Expense{}}
+
+      iex> create_expense_with_groups(%{field: bad_value}, [])
+      {:error, %Ecto.Changeset{}}
+
+  """
+  def create_expense_with_groups(attrs, group_ids) when is_list(group_ids) do
+    Repo.transaction(fn ->
+      with {:ok, expense} <- create_expense(attrs) do
+        now = DateTime.utc_now() |> DateTime.truncate(:second)
+
+        expense_groups =
+          Enum.map(group_ids, fn group_id ->
+            %{
+              expense_id: expense.id,
+              group_id: group_id,
+              inserted_at: now,
+              updated_at: now
+            }
+          end)
+
+        if expense_groups != [] do
+          {_count, _} = Repo.insert_all("expense_groups", expense_groups)
+        end
+
+        get_expense_with_associations!(expense.id)
+      else
+        {:error, changeset} -> Repo.rollback(changeset)
+      end
+    end)
+  end
+
   @doc """
   Updates a expense.
 
@@ -105,6 +143,28 @@ defmodule SplitApp.Expenses do
     |> Repo.update()
   end
 
+  @doc """
+  Updates an expense with group associations.
+
+  ## Examples
+
+      iex> update_expense_with_groups(expense, %{field: new_value}, [group1, group2])
+      {:ok, %Expense{}}
+
+      iex> update_expense_with_groups(expense, %{field: bad_value}, [])
+      {:error, %Ecto.Changeset{}}
+
+  """
+  def update_expense_with_groups(%Expense{} = expense, attrs, group_ids)
+      when is_list(group_ids) do
+    groups = SplitApp.Groups.get_groups_by_ids(group_ids)
+
+    expense
+    |> Repo.preload(:groups)
+    |> Expense.changeset_with_groups(attrs, groups)
+    |> Repo.update()
+  end
+
   @doc """
   Deletes a expense.
 

lib/split_app/expenses/expense.ex

@@ -22,6 +22,13 @@ defmodule SplitApp.Expenses.Expense do
     |> validate_money(:amount)
   end
 
+  @doc false
+  def changeset(expense, attrs, groups) do
+    expense
+    |> changeset(attrs)
+    |> put_assoc(:groups, groups)
+  end
+
   defp validate_money(changeset, field) do
     validate_change(changeset, field, fn
       _, %Money{amount: amount, currency: currency} when amount > 0 and not is_nil(currency) -> []

lib/split_app/groups.ex

@@ -40,6 +40,23 @@ defmodule SplitApp.Groups do
   """
   def get_group!(id), do: Repo.get!(Group, id)
 
+  @doc """
+  Gets multiple groups by their IDs.
+
+  ## Examples
+
+      iex> get_groups_by_ids([1, 2, 3])
+      [%Group{}, %Group{}, ...]
+
+      iex> get_groups_by_ids([])
+      []
+
+  """
+  def get_groups_by_ids(ids) when is_list(ids) do
+    from(g in Group, where: g.id in ^ids)
+    |> Repo.all()
+  end
+
   @doc """
   Gets a single group only if the user is a member.
 

lib/split_app_web/live/dashboard_live.ex

@@ -1,7 +1,9 @@
 defmodule SplitAppWeb.DashboardLive do
   use SplitAppWeb, :live_view
   alias SplitApp.Groups
+  alias SplitApp.Groups.Group
   alias SplitApp.Expenses
+  alias SplitApp.Expenses.Expense
 
   @impl true
   def mount(_params, _session, socket) do
@@ -13,7 +15,88 @@ defmodule SplitAppWeb.DashboardLive do
      socket
      |> assign(:groups, groups)
      |> assign(:recent_expenses, recent_expenses)
-     |> assign(:page_title, "Dashboard")}
+     |> assign(:page_title, "Dashboard")
+     |> assign(:show_expense_modal, false)
+     |> assign(:expense, nil)
+     |> assign(:show_group_modal, false)
+     |> assign(:group, nil)}
+  end
+
+  @impl true
+  def handle_params(_params, _url, socket) do
+    {:noreply, socket}
+  end
+
+  @impl true
+  def handle_event("new_expense", _params, socket) do
+    {:noreply,
+     socket
+     |> assign(:show_expense_modal, true)
+     |> assign(:expense, %Expense{created_by_id: socket.assigns.current_user.id})}
+  end
+
+  @impl true
+  def handle_event("new_group", _params, socket) do
+    {:noreply,
+     socket
+     |> assign(:show_group_modal, true)
+     |> assign(:group, %Group{})}
+  end
+
+  @impl true
+  def handle_event("close_modal", _params, socket) do
+    {:noreply,
+     socket
+     |> assign(:show_expense_modal, false)
+     |> assign(:expense, nil)
+     |> assign(:show_group_modal, false)
+     |> assign(:group, nil)}
+  end
+
+  @impl true
+  def handle_event("close_expense_modal", _params, socket) do
+    {:noreply,
+     socket
+     |> assign(:show_expense_modal, false)
+     |> assign(:expense, nil)}
+  end
+
+  @impl true
+  def handle_event("close_group_modal", _params, socket) do
+    {:noreply,
+     socket
+     |> assign(:show_group_modal, false)
+     |> assign(:group, nil)}
+  end
+
+  @impl true
+  def handle_info({SplitAppWeb.ExpenseLive.FormComponent, {:saved, _expense}}, socket) do
+    user = socket.assigns.current_user
+    recent_expenses = Expenses.list_expenses_by_user(user.id) |> Enum.take(5)
+
+    {:noreply,
+     socket
+     |> assign(:recent_expenses, recent_expenses)
+     |> assign(:show_expense_modal, false)
+     |> assign(:expense, nil)
+     |> put_flash(:info, "Expense created successfully")}
+  end
+
+  @impl true
+  def handle_info({SplitAppWeb.GroupLive.FormComponent, {:saved, _group}}, socket) do
+    user = socket.assigns.current_user
+    groups = Groups.list_user_groups(user)
+
+    {:noreply,
+     socket
+     |> assign(:groups, groups)
+     |> assign(:show_group_modal, false)
+     |> assign(:group, nil)}
+  end
+
+  @impl true
+  def handle_info({SplitAppWeb.GroupLive.FormComponent, {:put_flash, {type, message}}}, socket) do
+    {:noreply, put_flash(socket, type, message)}
   end
 
   @impl true
@@ -27,7 +110,7 @@ defmodule SplitAppWeb.DashboardLive do
 
     <!-- Quick Actions -->
       <div class="mt-8 grid grid-cols-1 gap-4 sm:grid-cols-2">
-        <.link navigate={~p"/expenses/new"} class="group">
+        <button phx-click="new_expense" class="group text-left">
           <div class="rounded-lg border-2 border-dashed border-gray-300 p-6 text-center hover:border-gray-400 transition-colors">
             <div class="mx-auto h-12 w-12 text-gray-400 group-hover:text-gray-500">
               <svg
@@ -49,9 +132,9 @@ defmodule SplitAppWeb.DashboardLive do
               Track a new expense and split it with your groups
             </p>
           </div>
-        </.link>
+        </button>
 
-        <.link navigate={~p"/groups/new"} class="group">
+        <button phx-click="new_group" class="group text-left">
           <div class="rounded-lg border-2 border-dashed border-gray-300 p-6 text-center hover:border-gray-400 transition-colors">
             <div class="mx-auto h-12 w-12 text-gray-400 group-hover:text-gray-500">
               <svg
@@ -71,7 +154,7 @@ defmodule SplitAppWeb.DashboardLive do
             <h3 class="mt-2 text-lg font-semibold text-gray-900">Create New Group</h3>
             <p class="mt-1 text-sm text-gray-500">Start a new group to organize shared expenses</p>
           </div>
-        </.link>
+        </button>
       </div>
 
     <!-- Recent Expenses -->
@@ -230,6 +313,40 @@ defmodule SplitAppWeb.DashboardLive do
         </div>
       </div>
     </div>
+
+    <.modal
+      :if={@show_expense_modal}
+      id="expense-modal"
+      show
+      on_cancel={JS.push("close_expense_modal")}
+    >
+      <.live_component
+        module={SplitAppWeb.ExpenseLive.FormComponent}
+        id={:new}
+        title="New Expense"
+        action={:new}
+        expense={@expense}
+        current_user={@current_user}
+        patch={~p"/dashboard"}
+      />
+    </.modal>
+
+    <.modal
+      :if={@show_group_modal}
+      id="group-modal"
+      show
+      on_cancel={JS.push("close_group_modal")}
+    >
+      <.live_component
+        module={SplitAppWeb.GroupLive.FormComponent}
+        id={:new}
+        title="New Group"
+        action={:new}
+        group={@group}
+        current_user={@current_user}
+        patch={~p"/dashboard"}
+      />
+    </.modal>
     """
   end
 

lib/split_app_web/live/expense_live/form_component.ex

@@ -3,6 +3,7 @@ defmodule SplitAppWeb.ExpenseLive.FormComponent do
 
   alias SplitApp.Expenses
   alias SplitApp.Expenses.Expense
+  alias SplitApp.Groups
 
   @impl true
   def render(assigns) do
@@ -30,6 +31,13 @@ defmodule SplitAppWeb.ExpenseLive.FormComponent do
           options={[{"USD", "USD"}, {"EUR", "EUR"}, {"GBP", "GBP"}]}
           value="USD"
         />
+        <.input
+          field={@form[:group_ids]}
+          type="select"
+          label="Groups"
+          multiple={true}
+          options={@group_options}
+        />
         <:actions>
           <.button phx-disable-with="Saving...">Save Expense</.button>
         </:actions>
@@ -42,11 +50,33 @@ defmodule SplitAppWeb.ExpenseLive.FormComponent do
   def update(%{expense: expense} = assigns, socket) do
     changeset = prepare_changeset_for_form(expense)
 
+    # Get the current user's groups for the dropdown
+    group_options =
+      if assigns.current_user do
+        Groups.list_user_groups(assigns.current_user)
+        |> Enum.map(fn group -> {group.name, group.id} end)
+      else
+        []
+      end
+
+    # Get current expense groups if editing
+    selected_groups =
+      if expense.id do
+        loaded_expense = Expenses.get_expense_with_associations!(expense.id)
+        Enum.map(loaded_expense.groups, & &1.id)
+      else
+        []
+      end
+
     {:ok,
      socket
      |> assign(assigns)
+     |> assign(:group_options, group_options)
+     |> assign(:selected_groups, selected_groups)
      |> assign_new(:form, fn ->
-       to_form(changeset)
+       changeset
+       |> Map.put(:changes, Map.put(changeset.changes, :group_ids, selected_groups))
+       |> to_form()
      end)}
   end
 
@@ -63,7 +93,24 @@ defmodule SplitAppWeb.ExpenseLive.FormComponent do
   end
 
   defp save_expense(socket, :edit, expense_params) do
-    case Expenses.update_expense(socket.assigns.expense, expense_params) do
+    # Extract group_ids and remove from params
+    {group_ids, params_without_groups} = Map.pop(expense_params, "group_ids", [])
+
+    # Convert group_ids to integers
+    group_ids = Enum.map(group_ids || [], &String.to_integer/1)
+
+    result =
+      if group_ids == [] do
+        Expenses.update_expense(socket.assigns.expense, params_without_groups)
+      else
+        Expenses.update_expense_with_groups(
+          socket.assigns.expense,
+          params_without_groups,
+          group_ids
+        )
+      end
+
+    case result do
       {:ok, expense} ->
         notify_parent({:saved, expense})
 
@@ -81,7 +128,20 @@ defmodule SplitAppWeb.ExpenseLive.FormComponent do
     params_with_user =
       Map.put(expense_params, "created_by_id", socket.assigns.expense.created_by_id)
 
-    case Expenses.create_expense(params_with_user) do
+    # Extract group_ids and remove from params
+    {group_ids, params_without_groups} = Map.pop(params_with_user, "group_ids", [])
+
+    # Convert group_ids to integers
+    group_ids = Enum.map(group_ids || [], &String.to_integer/1)
+
+    result =
+      if group_ids == [] do
+        Expenses.create_expense(params_without_groups)
+      else
+        Expenses.create_expense_with_groups(params_without_groups, group_ids)
+      end
+
+    case result do
       {:ok, expense} ->
         notify_parent({:saved, expense})