defmodule MvWeb.MemberLive.Show do
  @moduledoc """
  LiveView for displaying a single member's details.

  ## Features
  - Display all member information in grouped sections
  - Tab navigation for future features (Payments)
  - Show custom field values with type-based formatting
  - Navigate to edit form
  - Return to member list

  ## Sections
  - Personal Data: Name, address, contact information, membership dates, notes
  - Custom Fields: Dynamic fields in uniform grid layout (sorted by name)
  - Payment Data: Mockup section with placeholder data

  ## Navigation
  - Back to member list
  - Edit member (with return_to parameter for back navigation)
  """
  use MvWeb, :live_view
  import Ash.Query

  alias MvWeb.Helpers.MembershipFeeHelpers

  @impl true
  def render(assigns) do
    ~H"""
    <Layouts.app flash={@flash} current_user={@current_user}>
      <%!-- Header with Back button, Name, and Edit button --%>
      <div class="flex items-center justify-between gap-4 pb-4">
        <.button navigate={~p"/members"} aria-label={gettext("Back to members list")}>
          <.icon name="hero-arrow-left" class="size-4" />
          {gettext("Back")}
        </.button>

        <h1 class="text-2xl font-bold text-center flex-1">
          {@member.first_name} {@member.last_name}
        </h1>

        <.button variant="primary" navigate={~p"/members/#{@member}/edit?return_to=show"}>
          {gettext("Edit Member")}
        </.button>
      </div>

      <%!-- Tab Navigation --%>
      <div role="tablist" class="tabs tabs-bordered mb-6">
        <button
          role="tab"
          class={["tab", if(@active_tab == :contact, do: "tab-active", else: "")]}
          aria-selected={@active_tab == :contact}
          phx-click="switch_tab"
          phx-value-tab="contact"
        >
          <.icon name="hero-identification" class="size-4 mr-2" />
          {gettext("Contact Data")}
        </button>
        <button
          role="tab"
          class={["tab", if(@active_tab == :membership_fees, do: "tab-active", else: "")]}
          aria-selected={@active_tab == :membership_fees}
          phx-click="switch_tab"
          phx-value-tab="membership_fees"
        >
          <.icon name="hero-credit-card" class="size-4 mr-2" />
          {gettext("Membership Fees")}
        </button>
      </div>

      <%= if @active_tab == :contact do %>
        <%!-- Contact Data Tab Content --%>
        <%!-- Personal Data and Custom Fields Row --%>
        <div class="grid grid-cols-1 lg:grid-cols-2 gap-6 mb-6">
          <%!-- Personal Data Section --%>
          <div>
            <.section_box title={gettext("Personal Data")}>
              <div class="space-y-4">
                <%!-- Name Row --%>
                <div class="flex gap-6">
                  <.data_field label={gettext("First Name")} value={@member.first_name} class="w-48" />
                  <.data_field label={gettext("Last Name")} value={@member.last_name} class="w-48" />
                </div>

                <%!-- Address --%>
                <div>
                  <.data_field label={gettext("Address")} value={format_address(@member)} />
                </div>

                <%!-- Email --%>
                <div>
                  <.data_field label={gettext("Email")}>
                    <a
                      href={"mailto:#{MvWeb.MemberLive.Index.format_member_email(@member)}"}
                      class="text-blue-700 hover:text-blue-800 underline"
                    >
                      {@member.email}
                    </a>
                  </.data_field>
                </div>

                <%!-- Phone --%>
                <div>
                  <.data_field label={gettext("Phone")} value={@member.phone_number} />
                </div>

                <%!-- Membership Dates Row --%>
                <div class="flex gap-6">
                  <.data_field
                    label={gettext("Join Date")}
                    value={format_date(@member.join_date)}
                    class="w-28"
                  />
                  <.data_field
                    label={gettext("Exit Date")}
                    value={format_date(@member.exit_date)}
                    class="w-28"
                  />
                </div>

                <%!-- Linked User --%>
                <div>
                  <.data_field label={gettext("Linked User")}>
                    <%= if @member.user do %>
                      <.link
                        navigate={~p"/users/#{@member.user}"}
                        class="text-blue-700 hover:text-blue-800 underline inline-flex items-center gap-1"
                      >
                        <.icon name="hero-user" class="size-4" />
                        {@member.user.email}
                      </.link>
                    <% else %>
                      <span class="text-base-content/70 italic">{gettext("No user linked")}</span>
                    <% end %>
                  </.data_field>
                </div>

                <%!-- Notes --%>
                <%= if @member.notes && String.trim(@member.notes) != "" do %>
                  <div>
                    <.data_field label={gettext("Notes")}>
                      <p class="whitespace-pre-wrap text-base-content/80">{@member.notes}</p>
                    </.data_field>
                  </div>
                <% end %>
              </div>
            </.section_box>
          </div>

          <%!-- Custom Fields Section --%>
          <%= if Enum.any?(@member.custom_field_values) do %>
            <div>
              <.section_box title={gettext("Custom Fields")}>
                <div class="grid grid-cols-2 gap-4">
                  <%= for cfv <- sort_custom_field_values(@member.custom_field_values) do %>
                    <% custom_field = cfv.custom_field %>
                    <% value_type = custom_field && custom_field.value_type %>
                    <.data_field label={custom_field && custom_field.name}>
                      {format_custom_field_value(cfv.value, value_type)}
                    </.data_field>
                  <% end %>
                </div>
              </.section_box>
            </div>
          <% end %>
        </div>

        <%!-- Payment Data Section --%>
        <div class="max-w-xl">
          <.section_box title={gettext("Payment Data")}>
            <%= if @member.membership_fee_type do %>
              <div class="flex gap-6 flex-nowrap overflow-x-auto">
                <.data_field
                  label={gettext("Type")}
                  value={@member.membership_fee_type.name}
                  class="w-32"
                />
                <.data_field
                  label={gettext("Membership Fee")}
                  value={MembershipFeeHelpers.format_currency(@member.membership_fee_type.amount)}
                  class="w-24"
                />
                <.data_field
                  label={gettext("Payment Cycle")}
                  value={MembershipFeeHelpers.format_interval(@member.membership_fee_type.interval)}
                  class="w-28"
                />
                <.data_field label={gettext("Last Cycle")} class="w-28 whitespace-nowrap">
                  <%= if @member.last_cycle_status do %>
                    <% status = @member.last_cycle_status %>
                    <span class={["badge", MembershipFeeHelpers.status_color(status)]}>
                      {format_status_label(status)}
                    </span>
                  <% else %>
                    <span class="badge badge-ghost">{gettext("No cycles")}</span>
                  <% end %>
                </.data_field>
                <.data_field label={gettext("Current Cycle")} class="w-32 whitespace-nowrap">
                  <%= if @member.current_cycle_status do %>
                    <% status = @member.current_cycle_status %>
                    <span class={["badge", MembershipFeeHelpers.status_color(status)]}>
                      {format_status_label(status)}
                    </span>
                  <% else %>
                    <span class="badge badge-ghost">{gettext("No cycles")}</span>
                  <% end %>
                </.data_field>
              </div>
            <% else %>
              <div class="text-base-content/70 italic">
                {gettext("No membership fee type assigned")}
              </div>
            <% end %>
          </.section_box>
        </div>
      <% end %>

      <%= if @active_tab == :membership_fees do %>
        <%!-- Membership Fees Tab Content --%>
        <.live_component
          module={MvWeb.MemberLive.Show.MembershipFeesComponent}
          id={"membership-fees-#{@member.id}"}
          member={@member}
        />
      <% end %>
    </Layouts.app>
    """
  end

  @impl true
  def mount(_params, _session, socket) do
    {:ok, assign(socket, :active_tab, :contact)}
  end

  @impl true
  def handle_params(%{"id" => id}, _, socket) do
    query =
      Mv.Membership.Member
      |> filter(id == ^id)
      |> load([
        :user,
        :membership_fee_type,
        custom_field_values: [:custom_field],
        membership_fee_cycles: [:membership_fee_type]
      ])

    member = Ash.read_one!(query)

    # Calculate last and current cycle status from loaded cycles
    last_cycle_status = get_last_cycle_status(member)
    current_cycle_status = get_current_cycle_status(member)

    member =
      member
      |> Map.put(:last_cycle_status, last_cycle_status)
      |> Map.put(:current_cycle_status, current_cycle_status)

    {:noreply,
     socket
     |> assign(:page_title, page_title(socket.assigns.live_action))
     |> assign(:member, member)}
  end

  @impl true
  def handle_event("switch_tab", %{"tab" => "contact"}, socket) do
    {:noreply, assign(socket, :active_tab, :contact)}
  end

  def handle_event("switch_tab", %{"tab" => "membership_fees"}, socket) do
    {:noreply, assign(socket, :active_tab, :membership_fees)}
  end

  defp page_title(:show), do: gettext("Show Member")
  defp page_title(:edit), do: gettext("Edit Member")

  # -----------------------------------------------------------------
  # Helper Components
  # -----------------------------------------------------------------

  # Renders a section box with border and title.
  attr :title, :string, required: true
  slot :inner_block, required: true

  defp section_box(assigns) do
    ~H"""
    <section class="mb-6">
      <h2 class="text-lg font-semibold mb-3">{@title}</h2>
      <div class="border border-base-300 rounded-lg p-4 bg-base-100">
        {render_slot(@inner_block)}
      </div>
    </section>
    """
  end

  # Renders a labeled data field.
  attr :label, :string, required: true
  attr :value, :string, default: nil
  attr :class, :string, default: ""
  slot :inner_block

  defp data_field(assigns) do
    ~H"""
    <dl class={@class}>
      <dt class="text-sm font-medium text-base-content/70">{@label}</dt>
      <dd class="mt-1 text-base-content">
        <%= if @inner_block != [] do %>
          {render_slot(@inner_block)}
        <% else %>
          {display_value(@value)}
        <% end %>
      </dd>
    </dl>
    """
  end

  # -----------------------------------------------------------------
  # Helper Functions
  # -----------------------------------------------------------------

  defp display_value(nil), do: ""
  defp display_value(""), do: ""
  defp display_value(value), do: value

  defp format_status_label(:paid), do: gettext("Paid")
  defp format_status_label(:unpaid), do: gettext("Unpaid")
  defp format_status_label(:suspended), do: gettext("Suspended")
  defp format_status_label(nil), do: gettext("No status")

  defp get_last_cycle_status(member) do
    case MembershipFeeHelpers.get_last_completed_cycle(member) do
      nil -> nil
      cycle -> cycle.status
    end
  end

  defp get_current_cycle_status(member) do
    case MembershipFeeHelpers.get_current_cycle(member) do
      nil -> nil
      cycle -> cycle.status
    end
  end

  defp format_address(member) do
    street_part =
      [member.street, member.house_number]
      |> Enum.filter(&(&1 && &1 != ""))
      |> Enum.join(" ")

    city_part =
      [member.postal_code, member.city]
      |> Enum.filter(&(&1 && &1 != ""))
      |> Enum.join(" ")

    [street_part, city_part]
    |> Enum.filter(&(&1 != ""))
    |> Enum.join(", ")
    |> case do
      "" -> nil
      address -> address
    end
  end

  defp format_date(nil), do: nil

  defp format_date(%Date{} = date) do
    Calendar.strftime(date, "%d.%m.%Y")
  end

  defp format_date(date), do: to_string(date)

  # Sorts custom field values by custom field name
  defp sort_custom_field_values(custom_field_values) do
    Enum.sort_by(custom_field_values, fn cfv ->
      (cfv.custom_field && cfv.custom_field.name) || ""
    end)
  end

  # Formats custom field value based on type
  defp format_custom_field_value(%Ash.Union{value: value, type: type}, _expected_type) do
    format_custom_field_value(value, type)
  end

  defp format_custom_field_value(nil, _type), do: "—"

  defp format_custom_field_value(value, :boolean) when is_boolean(value) do
    if value, do: gettext("Yes"), else: gettext("No")
  end

  defp format_custom_field_value(%Date{} = date, :date) do
    Calendar.strftime(date, "%d.%m.%Y")
  end

  defp format_custom_field_value(value, :email) when is_binary(value) do
    assigns = %{email: value}

    ~H"""
    <a href={"mailto:#{@email}"} class="text-blue-700 hover:text-blue-800 underline">{@email}</a>
    """
  end

  defp format_custom_field_value(value, :integer) when is_integer(value) do
    Integer.to_string(value)
  end

  defp format_custom_field_value(value, _type) when is_binary(value) do
    if String.trim(value) == "", do: "—", else: value
  end

  defp format_custom_field_value(value, _type), do: to_string(value)
end