defmodule MvWeb.MemberLive.Show.DeactivateComponent do
  @moduledoc """
  LiveComponent owning the member deactivate/reactivate sub-flow on the member show page.

  ## Features
  - Deactivate control (shown when the member has no exit_date)
  - Reactivate control (shown when the member has an exit_date)
  - Date-selection modal (default: today, future dates allowed) for deactivation
  - Routes both actions through `Membership.update_member/2` with the real user actor,
    inheriting the `exit_date > join_date` validation and the cycle-regeneration hook.

  Controls are gated on `:update` permission for the member. On success the component
  notifies the parent with `{:member_updated, member}`, which the parent already handles.
  """
  use MvWeb, :live_component

  import MvWeb.Authorization, only: [can?: 3]

  alias Mv.Membership
  alias MvWeb.Helpers.MemberHelpers

  @impl true
  def render(assigns) do
    ~H"""
    <div id={@id}>
      <%= if @can_update do %>
        <section class="mt-8 mb-6" aria-labelledby="membership-state-heading">
          <h2 id="membership-state-heading" class="text-lg font-semibold mb-3">
            {gettext("Membership status")}
          </h2>
          <div class="border border-base-300 rounded-lg p-4 bg-base-100">
            <%= if @member.exit_date do %>
              <p class="text-base-content/70 mb-4">
                {gettext(
                  "This member is deactivated (exit date set). Reactivating clears the exit date."
                )}
              </p>
              <.button
                id="reactivate-member-trigger"
                data-testid="member-reactivate"
                variant="primary"
                phx-click="reactivate"
                phx-target={@myself}
                aria-label={
                  gettext("Reactivate member %{name}", name: MemberHelpers.display_name(@member))
                }
              >
                <.icon name="hero-arrow-uturn-left" class="size-4" />
                {gettext("Reactivate member")}
              </.button>
            <% else %>
              <p class="text-base-content/70 mb-4">
                {gettext(
                  "Deactivating this member records an exit date. You can reactivate them later."
                )}
              </p>
              <.button
                id="deactivate-member-trigger"
                data-testid="member-deactivate"
                variant="outline"
                phx-click="open_modal"
                phx-target={@myself}
                aria-label={
                  gettext("Deactivate member %{name}", name: MemberHelpers.display_name(@member))
                }
              >
                <.icon name="hero-arrow-right-on-rectangle" class="size-4" />
                {gettext("Deactivate member")}
              </.button>
            <% end %>
          </div>
        </section>
      <% end %>

      <%= if @show_modal do %>
        <dialog
          id="deactivate-member-modal"
          class="modal modal-open"
          role="dialog"
          aria-labelledby="deactivate-member-modal-title"
          phx-keydown="dialog_keydown"
          phx-target={@myself}
        >
          <div class="modal-box">
            <h3 id="deactivate-member-modal-title" class="text-lg font-bold">
              {gettext("When did this member leave?")}
            </h3>
            <form phx-submit="deactivate" phx-target={@myself}>
              <.input
                type="date"
                id="deactivate-exit-date"
                name="exit_date"
                label={gettext("Exit date")}
                value={@exit_date}
                errors={if @error, do: [@error], else: []}
                required
                phx-mounted={JS.focus()}
              />
              <div class="modal-action">
                <.button
                  type="button"
                  variant="neutral"
                  phx-click="cancel_modal"
                  phx-target={@myself}
                >
                  {gettext("Cancel")}
                </.button>
                <.button type="submit" variant="primary">{gettext("Deactivate")}</.button>
              </div>
            </form>
          </div>
        </dialog>
      <% end %>
    </div>
    """
  end

  @impl true
  def update(assigns, socket) do
    {:ok,
     socket
     |> assign(assigns)
     |> assign(:can_update, can?(assigns.current_user, :update, assigns.member))
     |> assign_new(:show_modal, fn -> false end)
     |> assign_new(:exit_date, fn -> Date.utc_today() end)
     |> assign_new(:error, fn -> nil end)}
  end

  @impl true
  def handle_event("open_modal", _params, socket) do
    {:noreply,
     socket
     |> assign(:show_modal, true)
     |> assign(:exit_date, Date.utc_today())
     |> assign(:error, nil)}
  end

  def handle_event("cancel_modal", _params, socket) do
    {:noreply, close_modal(socket)}
  end

  def handle_event("dialog_keydown", %{"key" => key}, socket) when key in ["Escape", "Esc"] do
    {:noreply, close_modal(socket)}
  end

  def handle_event("dialog_keydown", _params, socket), do: {:noreply, socket}

  def handle_event("deactivate", %{"exit_date" => exit_date_str}, socket) do
    case Date.from_iso8601(exit_date_str) do
      {:ok, exit_date} ->
        apply_exit_date(socket, exit_date, show_inline_error: true)

      {:error, _reason} ->
        {:noreply, assign(socket, :error, gettext("Invalid date format"))}
    end
  end

  def handle_event("reactivate", _params, socket) do
    apply_exit_date(socket, nil, show_inline_error: false)
  end

  defp apply_exit_date(socket, exit_date, opts) do
    member = socket.assigns.member
    actor = socket.assigns.current_user

    case Membership.update_member(member, %{exit_date: exit_date}, actor: actor) do
      {:ok, updated_member} ->
        send(self(), {:member_updated, updated_member})

        {:noreply,
         socket
         |> assign(:member, updated_member)
         |> close_modal()}

      {:error, error} ->
        if opts[:show_inline_error] do
          {:noreply, assign(socket, :error, format_error(error))}
        else
          send(self(), {:put_flash, :error, format_error(error)})
          {:noreply, socket}
        end
    end
  end

  defp close_modal(socket) do
    socket
    |> assign(:show_modal, false)
    |> assign(:error, nil)
  end

  defp format_error(%Ash.Error.Invalid{errors: errors}) do
    Enum.map_join(errors, ", ", fn
      %{message: message} -> message
      other -> inspect(other)
    end)
  end

  defp format_error(%Ash.Error.Forbidden{}) do
    gettext("You are not allowed to perform this action.")
  end

  defp format_error(_error), do: gettext("An error occurred")
end