defmodule BerrypodWeb.Shop.Collection do
  use BerrypodWeb, :live_view

  alias Berrypod.Products

  @sort_options [
    {"featured", "Featured"},
    {"newest", "Newest"},
    {"price_asc", "Price: Low to High"},
    {"price_desc", "Price: High to Low"},
    {"name_asc", "Name: A-Z"},
    {"name_desc", "Name: Z-A"}
  ]

  @impl true
  def mount(_params, _session, socket) do
    socket =
      socket
      |> assign(:sort_options, @sort_options)
      |> assign(:current_sort, "featured")

    {:ok, socket}
  end

  @impl true
  def handle_params(%{"slug" => slug} = params, _uri, socket) do
    sort = params["sort"] || "featured"

    case load_collection(slug, sort) do
      {:ok, title, category, products} ->
        {:noreply,
         socket
         |> assign(:page_title, title)
         |> assign(:page_description, collection_description(title))
         |> assign(:og_url, BerrypodWeb.Endpoint.url() <> "/collections/#{slug}")
         |> assign(:collection_title, title)
         |> assign(:current_category, category)
         |> assign(:current_sort, sort)
         |> assign(:products, products)}

      :not_found ->
        {:noreply,
         socket
         |> put_flash(:error, "Collection not found")
         |> push_navigate(to: ~p"/collections/all")}
    end
  end

  defp load_collection("all", sort) do
    {:ok, "All Products", nil, Products.list_visible_products(sort: sort)}
  end

  defp load_collection("sale", sort) do
    {:ok, "Sale", :sale, Products.list_visible_products(on_sale: true, sort: sort)}
  end

  defp load_collection(slug, sort) do
    case Enum.find(Products.list_categories(), &(&1.slug == slug)) do
      nil ->
        :not_found

      category ->
        products = Products.list_visible_products(category: category.name, sort: sort)
        {:ok, category.name, category, products}
    end
  end

  @impl true
  def handle_event("sort_changed", %{"sort" => sort}, socket) do
    slug =
      case socket.assigns.current_category do
        nil -> "all"
        :sale -> "sale"
        category -> category.slug
      end

    {:noreply, push_patch(socket, to: ~p"/collections/#{slug}?sort=#{sort}")}
  end

  defp collection_description("All Products"), do: "Browse our full range of products."
  defp collection_description("Sale"), do: "Browse our current sale items."
  defp collection_description(title), do: "Browse our #{String.downcase(title)} collection."

  defp collection_path(slug, "featured"), do: ~p"/collections/#{slug}"
  defp collection_path(slug, sort), do: ~p"/collections/#{slug}?sort=#{sort}"

  @impl true
  def render(assigns) do
    ~H"""
    <.shop_layout {layout_assigns(assigns)} active_page="collection">
      <main id="main-content">
        <.collection_header
          title={@collection_title}
          product_count={length(@products)}
        />

        <div class="page-container collection-body">
          <.collection_filter_bar
            categories={@categories}
            current_slug={
              case @current_category do
                :sale -> "sale"
                nil -> nil
                cat -> cat.slug
              end
            }
            sort_options={@sort_options}
            current_sort={@current_sort}
          />

          <.product_grid theme_settings={@theme_settings}>
            <%= for product <- @products do %>
              <.product_card
                product={product}
                theme_settings={@theme_settings}
                mode={@mode}
                variant={:default}
                show_category={@current_category in [nil, :sale]}
              />
            <% end %>
          </.product_grid>

          <%= if @products == [] do %>
            <div class="collection-empty">
              <p>No products found in this collection.</p>
              <.link navigate={~p"/collections/all"} class="collection-empty-link">
                View all products
              </.link>
            </div>
          <% end %>
        </div>
      </main>
    </.shop_layout>
    """
  end

  defp collection_filter_bar(assigns) do
    ~H"""
    <div class="filter-bar">
      <nav
        aria-label="Collection filters"
        id="collection-filters"
        phx-hook="CollectionFilters"
        class="collection-filters"
      >
        <ul class="collection-filter-pills">
          <li>
            <.link
              navigate={collection_path("all", @current_sort)}
              aria-current={@current_slug == nil && "page"}
              class={["collection-filter-pill", @current_slug == nil && "active"]}
            >
              All
            </.link>
          </li>
          <li>
            <.link
              navigate={collection_path("sale", @current_sort)}
              aria-current={@current_slug == "sale" && "page"}
              class={["collection-filter-pill", @current_slug == "sale" && "active"]}
            >
              Sale
            </.link>
          </li>
          <%= for category <- @categories do %>
            <li>
              <.link
                navigate={collection_path(category.slug, @current_sort)}
                aria-current={@current_slug == category.slug && "page"}
                class={["collection-filter-pill", @current_slug == category.slug && "active"]}
              >
                {category.name}
              </.link>
            </li>
          <% end %>
        </ul>
      </nav>

      <form action={~p"/collections/#{@current_slug || "all"}"} method="get" phx-change="sort_changed">
        <.shop_select
          name="sort"
          options={@sort_options}
          selected={@current_sort}
          aria-label="Sort products"
        />
        <noscript>
          <button type="submit" class="themed-button collection-sort-submit">Sort</button>
        </noscript>
      </form>
    </div>
    """
  end
end