defmodule FreediveWeb.LiliformLive do
  defmacro __using__(opts) do
    quote location: :keep, bind_quoted: [opts: opts] do
      use FreediveWeb, :live_view
      @behaviour FreediveWeb.LiliformLive
      @filters_all [
        %{
          title: "All",
          icon: "all",
          active: false,
          key: :all
        }
      ]

      def(mount(_params, _session, socket)) do
        items = items()
        filters = filters()
        socket = assign(socket, :opts, Keyword.get(unquote(opts), :opts, []))
        socket = assign(socket, :items_all, items)

        socket =
          assign(
            socket,
            :items,
            FreediveWeb.LiliformLive.filter(
              items,
              FreediveWeb.LiliformLive.get_active_filter(filters)
            )
          )

        socket = assign(socket, :filters, @filters_all ++ filters)
        socket = assign(socket, :query, "")
        {:ok, socket}
      end

      def(handle_event("search", %{"value" => query}, socket)) do
        items = search(query)
        socket = assign(socket, :items, items)
        {:noreply, socket}
      end

      def(handle_event("filter", %{"key" => key}, socket)) do
        key = String.to_existing_atom(key)
        items = FreediveWeb.LiliformLive.filter(socket.assigns.items_all, key)
        socket = assign(socket, :items, items)

        socket =
          assign(
            socket,
            :filters,
            Enum.map(socket.assigns.filters, fn filter ->
              Map.put(filter, :active, filter.key == key)
            end)
          )

        {:noreply, socket}
      end
    end
  end

  @callback items() :: [map]
  @callback filters() :: [map]
  @callback search(query :: String.t()) :: [map]

  def filter(items, key) do
    case key do
      :all ->
        items

      _ ->
        Enum.filter(items, fn item ->
          Map.get(item, key) == true
        end)
    end
  end

  def get_active_filter(filters) do
    filters |> Enum.find(& &1.active) |> Map.get(:key)
  end
end