towerops/lib/towerops_web/live/equipment_live/show.ex

defmodule ToweropsWeb.EquipmentLive.Show do
  @moduledoc false
  use ToweropsWeb, :live_view

  alias Towerops.Equipment
  alias Towerops.Monitoring
  alias Towerops.Snmp

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

  @impl true
  def handle_params(%{"id" => id}, _, socket) do
    if connected?(socket) do
      Phoenix.PubSub.subscribe(Towerops.PubSub, "equipment:#{id}")
      Process.send_after(self(), :refresh_data, 10_000)
    end

    {:noreply, load_equipment_data(socket, id)}
  end

  @impl true
  def handle_info(:refresh_data, socket) do
    Process.send_after(self(), :refresh_data, 10_000)
    {:noreply, load_equipment_data(socket, socket.assigns.equipment.id)}
  end

  @impl true
  def handle_info({:equipment_status_changed, _equipment_id, _new_status, _response_time}, socket) do
    {:noreply, load_equipment_data(socket, socket.assigns.equipment.id)}
  end

  @impl true
  def handle_info({:discovery_completed, _equipment_id}, socket) do
    {:noreply,
     socket
     |> load_equipment_data(socket.assigns.equipment.id)
     |> put_flash(:info, "Discovery completed")}
  end

  @impl true
  def handle_event("trigger_discovery", _params, socket) do
    equipment = socket.assigns.equipment

    if equipment.snmp_enabled do
      # Run discovery in background
      Task.start(fn ->
        Snmp.discover_equipment(equipment)
      end)

      {:noreply, put_flash(socket, :info, "Discovery started...")}
    else
      {:noreply, put_flash(socket, :error, "SNMP is not enabled for this equipment")}
    end
  end

  # Private functions

  defp load_equipment_data(socket, equipment_id) do
    equipment = Equipment.get_equipment!(equipment_id)
    recent_checks = Monitoring.list_equipment_checks(equipment_id, 50)
    snmp_data = load_snmp_data(equipment_id)

    # Calculate metrics for dashboard
    metrics = calculate_metrics(recent_checks, equipment)

    socket
    |> assign(:page_title, equipment.name)
    |> assign(:equipment, equipment)
    |> assign(:recent_checks, recent_checks)
    |> assign(:metrics, metrics)
    |> assign(:snmp_device, snmp_data.device)
    |> assign(:snmp_interfaces, snmp_data.interfaces)
    |> assign(:snmp_sensors, snmp_data.sensors)
  end

  defp calculate_metrics(checks, _equipment) do
    total_checks = length(checks)

    if total_checks > 0 do
      successful_checks = Enum.count(checks, &(&1.status == :success))
      uptime_percentage = Float.round(successful_checks / total_checks * 100, 1)

      avg_response_time =
        checks
        |> Enum.filter(&(&1.response_time_ms != nil))
        |> case do
          [] ->
            0

          valid_checks ->
            sum = Enum.reduce(valid_checks, 0, &(&1.response_time_ms + &2))
            Float.round(sum / length(valid_checks), 1)
        end

      %{
        uptime_percentage: uptime_percentage,
        avg_response_time: avg_response_time,
        total_checks: total_checks,
        successful_checks: successful_checks
      }
    else
      %{
        uptime_percentage: 0,
        avg_response_time: 0,
        total_checks: 0,
        successful_checks: 0
      }
    end
  end

  defp format_speed(speed_bps) when is_integer(speed_bps) do
    cond do
      speed_bps >= 1_000_000_000 ->
        "#{Float.round(speed_bps / 1_000_000_000, 1)} Gbps"

      speed_bps >= 1_000_000 ->
        "#{Float.round(speed_bps / 1_000_000, 1)} Mbps"

      speed_bps >= 1_000 ->
        "#{Float.round(speed_bps / 1_000, 1)} Kbps"

      true ->
        "#{speed_bps} bps"
    end
  end

  defp format_speed(_), do: "-"

  defp format_sensor_value(value, divisor) when is_number(value) and is_number(divisor) do
    result = value / divisor
    Float.round(result, 1)
  end

  defp format_sensor_value(_, _), do: "-"

  defp time_ago(nil), do: "Never"

  defp time_ago(datetime) do
    diff = DateTime.diff(DateTime.utc_now(), datetime, :second)

    cond do
      diff < 60 -> "#{diff}s ago"
      diff < 3600 -> "#{div(diff, 60)}m ago"
      diff < 86_400 -> "#{div(diff, 3600)}h ago"
      true -> "#{div(diff, 86_400)}d ago"
    end
  end

  defp load_snmp_data(equipment_id) do
    case Snmp.get_device_with_associations(equipment_id) do
      nil ->
        %{device: nil, interfaces: [], sensors: []}

      device ->
        # Preload latest readings for sensors
        sensors_with_readings =
          Enum.map(device.sensors, fn sensor ->
            latest_reading = Snmp.get_latest_sensor_reading(sensor.id)
            Map.put(sensor, :latest_reading, latest_reading)
          end)

        # Preload latest stats for interfaces
        interfaces_with_stats =
          Enum.map(device.interfaces, fn interface ->
            latest_stat = Snmp.get_latest_interface_stat(interface.id)
            Map.put(interface, :latest_stat, latest_stat)
          end)

        %{
          device: device,
          interfaces: interfaces_with_stats,
          sensors: sensors_with_readings
        }
    end
  end

  # SVG Chart helpers

  defp sparkline(checks, width, height) when is_list(checks) do
    if Enum.empty?(checks) or length(checks) < 2 do
      ""
    else
      # Get response times in reverse order (oldest to newest for left-to-right)
      data =
        checks
        |> Enum.reverse()
        |> Enum.map(fn check ->
          if check.response_time_ms, do: check.response_time_ms, else: 0
        end)

      max_value = Enum.max(data, fn -> 1 end)
      max_value = if max_value == 0, do: 1, else: max_value
      data_count = length(data)

      points =
        data
        |> Enum.with_index()
        |> Enum.map_join(" ", fn {value, index} ->
          x = index * (width / (data_count - 1))
          y = height - value / max_value * height
          "#{Float.round(x, 2)},#{Float.round(y, 2)}"
        end)

      assigns = %{points: points, width: width, height: height, data: data}

      ~H"""
      <svg viewBox={"0 0 #{@width} #{@height}"} class="w-full h-full">
        <polyline
          points={@points}
          fill="none"
          stroke="currentColor"
          stroke-width="2"
          class="text-blue-500"
        />
        <%= for {value, idx} <- Enum.with_index(@data) do %>
          <circle
            cx={idx * (@width / (length(@data) - 1))}
            cy={@height - value / Enum.max(@data, fn -> 1 end) * @height}
            r="2"
            class={if value == 0, do: "fill-red-500", else: "fill-blue-500"}
          />
        <% end %>
      </svg>
      """
    end
  end

  defp uptime_gauge(percentage) do
    assigns = %{percentage: percentage}

    color_class =
      cond do
        percentage >= 95 -> "bg-green-500"
        percentage >= 80 -> "bg-yellow-500"
        true -> "bg-red-500"
      end

    assigns = Map.put(assigns, :color_class, color_class)

    ~H"""
    <div class="relative w-full h-6 bg-zinc-200 dark:bg-zinc-700 rounded-full overflow-hidden">
      <div
        class={"absolute inset-y-0 left-0 #{@color_class} transition-all duration-500"}
        style={"width: #{@percentage}%"}
      >
      </div>
      <div class="absolute inset-0 flex items-center justify-center text-xs font-medium text-zinc-900 dark:text-zinc-100">
        {@percentage}%
      </div>
    </div>
    """
  end
end