defmodule PhoenixKit.Modules.Emails.Web.Details do
  @moduledoc """
  LiveView for displaying detailed information about a specific email log.

  Provides comprehensive view of email metadata, delivery status, events timeline,
  and performance analytics for individual emails.

  ## Features

  - **Complete Email Metadata**: Headers, size, attachments, template info
  - **Events Timeline**: Chronological view of all email events
  - **Delivery Status**: Real-time status tracking and updates
  - **Geographic Data**: Location info for opens and clicks
  - **Performance Metrics**: Individual email analytics
  - **Debugging Info**: Technical details for troubleshooting
  - **Related Emails**: Other emails in same campaign/template

  ## Route

  This LiveView is mounted at `{prefix}/admin/emails/:id` and requires
  appropriate admin permissions.

  Note: `{prefix}` is your configured PhoenixKit URL prefix (default: `/phoenix_kit`).

  ## Usage

      # In your Phoenix router
      live "/email-logs/:id", PhoenixKitWeb.Live.Modules.Emails.EmailDetailsLive, :show

  ## Permissions

  Access is restricted to users with admin or owner roles in PhoenixKit.
  """

  use PhoenixKitWeb, :live_view

  require Logger

  alias PhoenixKit.Modules.Emails
  alias PhoenixKit.Modules.Emails.Log
  alias PhoenixKit.Settings
  alias PhoenixKit.Utils.Date, as: UtilsDate
  alias PhoenixKit.Utils.Routes

  import PhoenixKitWeb.Components.Core.Icons, only: [icon_arrow_left: 1]

  ## --- Lifecycle Callbacks ---

  @impl true
  def mount(%{"id" => id}, _session, socket) do
    # Check if email is enabled
    if Emails.enabled?() do
      case Integer.parse(id) do
        {email_id, _} ->
          # Get project title from settings
          project_title = Settings.get_setting("project_title", "PhoenixKit")

          socket =
            socket
            |> assign(:email_id, email_id)
            |> assign(:project_title, project_title)
            |> assign(:email_log, nil)
            |> assign(:events, [])
            |> assign(:related_emails, [])
            |> assign(:loading, true)
            |> assign(:syncing, false)
            |> load_email_data()

          {:ok, socket}

        _ ->
          {:ok,
           socket
           |> put_flash(:error, "Invalid email ID")
           |> push_navigate(to: Routes.path("/admin/emails"))}
      end
    else
      {:ok,
       socket
       |> put_flash(:error, "Email is not enabled")
       |> push_navigate(to: Routes.path("/admin/emails"))}
    end
  end

  ## --- Event Handlers ---

  @impl true
  def handle_event("refresh", _params, socket) do
    {:noreply,
     socket
     |> assign(:loading, true)
     |> load_email_data()}
  end

  @impl true
  def handle_event("sync_status", _params, socket) do
    if socket.assigns.email_log do
      # Determine which message ID to use for sync (prefer AWS message ID)
      {message_id, id_type} =
        if socket.assigns.email_log.aws_message_id do
          {socket.assigns.email_log.aws_message_id, "AWS SES message ID"}
        else
          {socket.assigns.email_log.message_id, "internal message ID"}
        end

      socket = assign(socket, :syncing, true)

      case Emails.sync_email_status(message_id) do
        {:ok, result} ->
          flash_message = build_sync_flash_message(result, id_type)
          flash_type = determine_flash_type(result)

          socket =
            socket
            |> assign(:syncing, false)
            |> put_flash(flash_type, flash_message)
            |> load_email_data()

          {:noreply, socket}

        {:error, reason} ->
          flash_message = build_error_flash_message(reason, message_id, socket, id_type)

          socket =
            socket
            |> assign(:syncing, false)
            |> put_flash(:error, flash_message)

          {:noreply, socket}
      end
    else
      {:noreply, put_flash(socket, :error, "❌ Email log not found")}
    end
  end

  @impl true
  def handle_event("toggle_headers", _params, socket) do
    {:noreply,
     socket
     |> assign(:show_headers, !Map.get(socket.assigns, :show_headers, false))}
  end

  @impl true
  def handle_event("toggle_body", _params, socket) do
    {:noreply,
     socket
     |> assign(:show_body, !Map.get(socket.assigns, :show_body, false))}
  end

  @impl true
  def handle_event("view_related", %{"campaign_id" => campaign_id}, socket) do
    {:noreply,
     socket
     |> push_navigate(to: Routes.path("/admin/emails?campaign_id=#{campaign_id}"))}
  end

  @impl true
  def handle_event("view_related", %{"template_name" => template_name}, socket) do
    {:noreply,
     socket
     |> push_navigate(to: Routes.path("/admin/emails?template_name=#{template_name}"))}
  end

  ## --- Template ---

  ## --- Private Helper Functions ---

  # Load email data and related information
  defp load_email_data(socket) do
    email_id = socket.assigns.email_id

    try do
      email_log = Emails.get_log!(email_id)
      events = Emails.list_events_for_log(email_id)
      related_emails = get_related_emails(email_log)

      socket
      |> assign(:email_log, email_log)
      |> assign(:events, events)
      |> assign(:related_emails, related_emails)
      |> assign(:loading, false)
      |> assign(:show_headers, false)
      |> assign(:show_body, false)
      |> assign(:page_title, "Email ##{email_id}")
    rescue
      Ecto.NoResultsError ->
        socket
        |> assign(:email_log, nil)
        |> assign(:events, [])
        |> assign(:related_emails, [])
        |> assign(:loading, false)

      error ->
        Logger.error("Failed to load email data: #{inspect(error)}")

        socket
        |> assign(:loading, false)
        |> put_flash(:error, "Failed to load email data")
    end
  end

  # Get related emails (same campaign or template)
  defp get_related_emails(%Log{
         campaign_id: campaign_id,
         template_name: template_name,
         id: current_id
       }) do
    filters = %{limit: 10}

    filters =
      cond do
        campaign_id -> Map.put(filters, :campaign_id, campaign_id)
        template_name -> Map.put(filters, :template_name, template_name)
        true -> filters
      end

    Emails.list_logs(filters)
    |> Enum.reject(fn log -> log.id == current_id end)
  end

  defp get_related_emails(_), do: []

  # Build event details list for success message
  defp build_event_details(sqs_events, dlq_events, events_failed) do
    details = []

    details =
      if sqs_events > 0, do: ["#{sqs_events} from SQS" | details], else: details

    details =
      if dlq_events > 0, do: ["#{dlq_events} from DLQ" | details], else: details

    if events_failed > 0, do: ["#{events_failed} failed" | details], else: details
  end

  # Build success flash message
  defp build_sync_flash_message(result, id_type) do
    events_processed = Map.get(result, :events_processed, 0)
    total_events_found = Map.get(result, :total_events_found, 0)
    sqs_events = Map.get(result, :sqs_events_found, 0)
    dlq_events = Map.get(result, :dlq_events_found, 0)
    events_failed = Map.get(result, :events_failed, 0)
    existing_log_found = Map.get(result, :existing_log_found, false)
    log_updated = Map.get(result, :log_updated, false)
    message = Map.get(result, :message, nil)

    cond do
      total_events_found > 0 and events_processed > 0 ->
        details = build_event_details(sqs_events, dlq_events, events_failed)
        source_info = if Enum.empty?(details), do: "", else: " (#{Enum.join(details, ", ")})"
        status_info = if log_updated, do: " - Email status updated", else: ""

        "✅ Processed #{events_processed}/#{total_events_found} events#{source_info}#{status_info} using #{id_type}"

      total_events_found > 0 and events_processed == 0 ->
        "⚠️ Found #{total_events_found} events but none could be processed successfully using #{id_type}"

      not existing_log_found ->
        "ℹ️ No email log found in database for #{id_type}. Events may be for a different email."

      true ->
        search_info = " (searched using #{id_type})"
        (message || "No new events found in SQS or DLQ queues") <> search_info
    end
  end

  # Determine flash type based on sync results
  defp determine_flash_type(result) do
    events_processed = Map.get(result, :events_processed, 0)
    total_events_found = Map.get(result, :total_events_found, 0)
    existing_log_found = Map.get(result, :existing_log_found, false)

    cond do
      events_processed > 0 -> :info
      total_events_found > 0 and events_processed == 0 -> :warning
      not existing_log_found -> :warning
      true -> :info
    end
  end

  # Build ID info string for error messages
  defp build_id_info(message_id, email_log, id_type) do
    if message_id == email_log.message_id do
      " (using #{id_type})"
    else
      " (using #{id_type}: #{String.slice(message_id, 0, 20)}...)"
    end
  end

  # Build error flash message
  defp build_error_flash_message(reason, message_id, socket, id_type) do
    case reason do
      "AWS credentials not configured. Please set AWS_ACCESS_KEY_ID and AWS_SECRET_ACCESS_KEY environment variables." ->
        "❌ AWS credentials not configured. Please set AWS_ACCESS_KEY_ID and AWS_SECRET_ACCESS_KEY environment variables."

      "Email is disabled. Please enable it in settings." ->
        "❌ Email is disabled. Please enable it in admin settings."

      reason ->
        id_info = build_id_info(message_id, socket.assigns.email_log, id_type)
        "❌ Sync failed: #{reason}#{id_info}"
    end
  end
end