defmodule BerrypodWeb.Admin.Dashboard do
  use BerrypodWeb, :live_view

  alias Berrypod.{Cart, Orders, Products, Settings}

  @impl true
  def mount(_params, _session, socket) do
    setup = Berrypod.Setup.setup_status()
    status_counts = Orders.count_orders_by_status()
    paid_count = Map.get(status_counts, "paid", 0)
    recent_orders = Orders.list_orders(status: "paid") |> Enum.take(5)

    {:ok,
     socket
     |> assign(:page_title, "Dashboard")
     |> assign(:setup, setup)
     |> assign(:show_checklist, show_checklist?(setup))
     |> assign(:checklist_collapsed, false)
     |> assign(:just_went_live, false)
     |> assign(:paid_count, paid_count)
     |> assign(:revenue, Orders.total_revenue())
     |> assign(:product_count, Products.count_products())
     |> assign(:recent_orders, recent_orders)}
  end

  # ── Events ──

  @impl true
  def handle_event("go_live", _params, socket) do
    {:ok, _} = Settings.set_site_live(true)
    setup = %{socket.assigns.setup | site_live: true}

    {:noreply,
     socket
     |> assign(:setup, setup)
     |> assign(:just_went_live, true)}
  end

  def handle_event("toggle_checklist", _params, socket) do
    {:noreply, assign(socket, :checklist_collapsed, !socket.assigns.checklist_collapsed)}
  end

  # ── Render ──

  @impl true
  def render(assigns) do
    ~H"""
    <.header>
      Dashboard
    </.header>

    <%!-- Celebration after go-live --%>
    <div :if={@just_went_live} class="setup-complete admin-card-spaced">
      <.icon name="hero-check-badge" class="setup-complete-icon" />
      <h2>Your shop is live!</h2>
      <p>Customers can now browse and buy from your shop.</p>
      <div class="setup-complete-actions">
        <.link href={~p"/"} class="admin-btn admin-btn-primary">
          <.icon name="hero-arrow-top-right-on-square-mini" class="size-4" /> View your shop
        </.link>
        <.link href="/?edit=theme" class="admin-btn admin-btn-secondary">
          <.icon name="hero-paint-brush-mini" class="size-4" /> Customise theme
        </.link>
      </div>
    </div>

    <%!-- Shop is live banner (not just now, but already live) --%>
    <div
      :if={@setup.site_live && !@just_went_live}
      class="admin-status-banner admin-status-banner-live admin-card-spaced"
    >
      <.icon name="hero-check-circle" class="size-5" />
      <span>Your shop is live</span>
    </div>

    <%!-- Setup in progress message --%>
    <div
      :if={@show_checklist && !@just_went_live && !@setup.setup_complete}
      class="admin-status-banner admin-status-banner-setup admin-card-spaced"
    >
      <.icon name="hero-wrench-screwdriver" class="size-5" />
      <span>Your admin account has been created. Continue the full setup below.</span>
    </div>

    <%!-- Launch checklist --%>
    <.launch_checklist
      :if={@show_checklist and !@just_went_live}
      setup={@setup}
      collapsed={@checklist_collapsed}
    />

    <%!-- Stats --%>
    <div class="admin-stats-grid">
      <.stat_card
        label="Orders"
        value={@paid_count}
        icon="hero-shopping-bag"
        href={~p"/admin/orders"}
      />
      <.stat_card
        label="Revenue"
        value={format_revenue(@revenue)}
        icon="hero-banknotes"
        href={~p"/admin/orders"}
      />
      <.stat_card
        label="Products"
        value={@product_count}
        icon="hero-cube"
        href={~p"/admin/products"}
      />
    </div>

    <%!-- Recent orders --%>
    <section class="dashboard-section">
      <div class="dashboard-section-header">
        <h2 class="admin-section-heading">Recent orders</h2>
        <.link navigate={~p"/admin/orders"} class="dashboard-view-all">
          View all &rarr;
        </.link>
      </div>

      <%= if @recent_orders == [] do %>
        <div class="dashboard-empty-orders">
          <div class="dashboard-empty-icon">
            <.icon name="hero-inbox" class="size-10" />
          </div>
          <p class="admin-text-medium">No orders yet</p>
          <p class="admin-help-text">
            Orders will appear here once customers check out.
          </p>
        </div>
      <% else %>
        <div class="dashboard-recent-orders">
          <table class="admin-table">
            <thead>
              <tr>
                <th>Order</th>
                <th>Date</th>
                <th>Customer</th>
                <th class="admin-cell-end">Total</th>
                <th>Fulfilment</th>
              </tr>
            </thead>
            <tbody>
              <tr
                :for={order <- @recent_orders}
                phx-click={JS.navigate(~p"/admin/orders/#{order}")}
                class="admin-table-row-clickable"
              >
                <td class="admin-text-medium">{order.order_number}</td>
                <td>{format_date(order.inserted_at)}</td>
                <td>{order.customer_email || "—"}</td>
                <td class="admin-cell-end">{Cart.format_price(order.total)}</td>
                <td><.fulfilment_pill status={order.fulfilment_status} /></td>
              </tr>
            </tbody>
          </table>
        </div>
      <% end %>
    </section>
    """
  end

  # ==========================================================================
  # Launch checklist component
  # ==========================================================================

  attr :setup, :map, required: true
  attr :collapsed, :boolean, required: true

  defp launch_checklist(assigns) do
    items = checklist_items(assigns.setup)

    done_count = Enum.count(items, & &1.done)
    total = length(items)
    progress_pct = round(done_count / total * 100)

    assigns =
      assigns
      |> assign(:items, items)
      |> assign(:done_count, done_count)
      |> assign(:total, total)
      |> assign(:progress_pct, progress_pct)
      |> assign(:can_go_live, assigns.setup.can_go_live)
      |> assign(:has_shipping, assigns.setup.has_shipping)

    ~H"""
    <div class="admin-checklist admin-card-spaced">
      <button type="button" phx-click="toggle_checklist" class="admin-checklist-header">
        <h2 class="admin-checklist-title">Launch checklist</h2>
        <div class="admin-checklist-progress">
          <span>{@done_count} of {@total}</span>
          <div class="admin-checklist-bar">
            <div class="admin-checklist-bar-fill" style={"width: #{@progress_pct}%"} />
          </div>
          <.icon
            name={if @collapsed, do: "hero-chevron-down-mini", else: "hero-chevron-up-mini"}
            class="size-4"
          />
        </div>
      </button>

      <ul :if={!@collapsed} class="admin-checklist-items">
        <li :for={item <- @items} class="admin-checklist-item">
          <span class={["admin-checklist-check", item.done && "admin-checklist-check-done"]}>
            <.icon :if={item.done} name="hero-check-mini" class="size-3" />
          </span>

          <div class="admin-checklist-content">
            <div class="admin-checklist-row">
              <span class={[
                "admin-checklist-label",
                item.done && "admin-checklist-label-done"
              ]}>
                {item.label}
                <span :if={item[:optional]} class="admin-checklist-optional">optional</span>
              </span>

              <span class="admin-checklist-action">
                <%= if item.key == :site_live do %>
                  <button
                    phx-click="go_live"
                    disabled={!@can_go_live}
                    class="admin-btn admin-btn-primary admin-btn-sm"
                  >
                    <.icon name="hero-rocket-launch-mini" class="size-4" /> Go live
                  </button>
                <% else %>
                  <.link
                    :if={!item.done}
                    navigate={item.href}
                    class="admin-btn admin-btn-secondary admin-btn-sm"
                  >
                    Start &rarr;
                  </.link>
                <% end %>
              </span>
            </div>

            <p :if={item[:hint] && !item.done} class="admin-checklist-hint">
              {item.hint}
              <a
                :if={item[:help_url]}
                href={item.help_url}
                target="_blank"
                rel="noopener noreferrer"
                class="admin-checklist-help"
              >
                <.icon name="hero-question-mark-circle-mini" class="size-4" />
                <span class="sr-only">Help (opens in new window)</span>
              </a>
            </p>

            <p
              :if={item.key == :site_live && !@can_go_live && !@has_shipping}
              class="admin-checklist-hint"
            >
              Shipping rates haven't synced yet. Try re-syncing your products from the <.link
                navigate="/admin/providers"
                class="admin-link"
              >providers page</.link>.
            </p>
          </div>
        </li>
      </ul>
    </div>
    """
  end

  defp checklist_items(setup) do
    [
      # Setup wizard items (matches guided flow step names)
      %{
        key: :provider_connected,
        label: "Connect a print provider",
        href: "/admin/providers",
        hint: "Link your Printify or Printful account to import products.",
        help_url:
          "https://help.printify.com/hc/en-us/articles/4483606633617-How-to-find-my-Printify-API-key"
      },
      %{
        key: :stripe_connected,
        label: "Connect Stripe for payments",
        href: "/admin/settings",
        hint: "Accept credit card payments from customers.",
        help_url: "https://stripe.com/docs/keys"
      },
      %{
        key: :email_configured,
        label: "Set up email",
        href: "/admin/settings/email",
        hint: "Send order confirmations, shipping updates, and newsletters."
      },
      # Post-setup items
      %{
        key: :products_synced,
        label: "Import products",
        href:
          if(setup.provider_connected,
            do: "/admin/products",
            else: "/admin/providers"
          ),
        hint: "Sync products from your print provider."
      },
      %{
        key: :has_shipping,
        label: "Set up shipping",
        href: "/admin/shipping",
        hint: "Configure shipping rates for your products."
      },
      %{
        key: :theme_customised,
        label: "Customise your shop",
        href: "/?edit=theme",
        hint: "Upload your logo, pick colours, and choose fonts.",
        optional: true
      },
      %{
        key: :has_orders,
        label: "Place a test order",
        href: "/",
        hint: "Use card 4242 4242 4242 4242 with any future expiry and CVC.",
        optional: true
      },
      %{key: :site_live, label: "Go live"}
    ]
    |> Enum.map(fn item ->
      Map.put(item, :done, Map.get(setup, item.key, false))
    end)
  end

  # ==========================================================================
  # Components
  # ==========================================================================

  attr :label, :string, required: true
  attr :value, :any, required: true
  attr :icon, :string, required: true
  attr :href, :string, required: true

  defp stat_card(assigns) do
    ~H"""
    <.link navigate={@href} class="admin-card dashboard-stat-link">
      <div class="admin-stat-card-body">
        <div class="admin-stat-icon">
          <.icon name={@icon} class="size-5" />
        </div>
        <div>
          <p class="admin-stat-value">{@value}</p>
          <p class="admin-stat-label">{@label}</p>
        </div>
      </div>
    </.link>
    """
  end

  defp fulfilment_pill(assigns) do
    {color_class, label} =
      case assigns.status do
        "unfulfilled" -> {"admin-status-pill-zinc", "unfulfilled"}
        "submitted" -> {"admin-status-pill-blue", "submitted"}
        "processing" -> {"admin-status-pill-amber", "processing"}
        "shipped" -> {"admin-status-pill-purple", "shipped"}
        "delivered" -> {"admin-status-pill-green", "delivered"}
        "failed" -> {"admin-status-pill-red", "failed"}
        _ -> {"admin-status-pill-zinc", assigns.status || "—"}
      end

    assigns = assign(assigns, color_class: color_class, label: label)

    ~H"""
    <span class={["admin-status-pill", @color_class]}>{@label}</span>
    """
  end

  # ==========================================================================
  # Helpers
  # ==========================================================================

  defp show_checklist?(setup) do
    not setup.site_live
  end

  defp format_revenue(amount_pence) when is_integer(amount_pence) do
    Cart.format_price(amount_pence)
  end

  defp format_revenue(_), do: "£0.00"

  defp format_date(datetime) do
    Calendar.strftime(datetime, "%d %b %Y")
  end
end