defmodule MicrowavepropWeb.MonitorLive.Show do
  @moduledoc "User-facing beacon-monitor detail at `/beacon-monitors/:id`."
  use MicrowavepropWeb, :live_view

  import Ecto.Query

  alias Microwaveprop.BeaconMeasurements
  alias Microwaveprop.BeaconMonitors
  alias Microwaveprop.BeaconMonitors.BeaconMonitor
  alias Microwaveprop.Beacons.Beacon
  alias Microwaveprop.Repo

  @impl true
  def mount(%{"id" => id}, _session, socket) do
    user = socket.assigns.current_scope.user
    monitor = BeaconMonitors.get_monitor!(id)

    if monitor.user_id == user.id do
      beacons = Repo.all(from b in Beacon, where: b.approved == true, order_by: b.callsign)
      measurements = BeaconMeasurements.list_recent_for_monitor(monitor.id, 20)

      {:ok,
       socket
       |> assign(:page_title, "My Monitor: #{monitor.name}")
       |> assign(:monitor, monitor)
       |> assign(:beacons, beacons)
       |> assign(:measurements, measurements)
       |> assign_form(monitor)}
    else
      {:ok,
       socket
       |> put_flash(:error, "You don't have access to that monitor.")
       |> push_navigate(to: ~p"/users/settings")}
    end
  end

  @impl true
  def render(assigns) do
    ~H"""
    <Layouts.app flash={@flash} current_scope={@current_scope} max_width="max-w-4xl">
      <.header>
        {@monitor.name}
        <:subtitle>Your beacon monitor</:subtitle>
      </.header>

      <div class="grid grid-cols-1 lg:grid-cols-2 gap-4 mb-6">
        <div class="card bg-base-200 shadow-sm">
          <div class="card-body">
            <h2 class="card-title text-sm">Hardware</h2>
            <dl class="text-sm space-y-1">
              <div class="flex justify-between">
                <dt class="opacity-70">Type</dt>
                <dd>{@monitor.hardware_type}</dd>
              </div>
              <div class="flex justify-between">
                <dt class="opacity-70">Serial / ID</dt>
                <dd>{@monitor.hardware_id}</dd>
              </div>
              <div class="flex justify-between">
                <dt class="opacity-70">Firmware</dt>
                <dd>{@monitor.firmware_version}</dd>
              </div>
              <div class="flex justify-between">
                <dt class="opacity-70">Antenna</dt>
                <dd>{@monitor.antenna_type}</dd>
              </div>
              <div class="flex justify-between">
                <dt class="opacity-70">Antenna gain</dt>
                <dd>{@monitor.antenna_gain_dbi && "#{@monitor.antenna_gain_dbi} dBi"}</dd>
              </div>
              <div class="flex justify-between">
                <dt class="opacity-70">Location</dt>
                <dd>
                  <%= if @monitor.lat && @monitor.lon do %>
                    {@monitor.lat}, {@monitor.lon}
                  <% else %>
                    <span class="opacity-50">&mdash;</span>
                  <% end %>
                </dd>
              </div>
            </dl>
          </div>
        </div>

        <div class="card bg-base-200 shadow-sm">
          <div class="card-body">
            <h2 class="card-title text-sm">Connection</h2>
            <dl class="text-sm space-y-1">
              <div class="flex justify-between">
                <dt class="opacity-70">Auth token</dt>
                <dd><code class="text-xs select-all break-all">{@monitor.token}</code></dd>
              </div>
              <div class="flex justify-between">
                <dt class="opacity-70">Last seen</dt>
                <dd>
                  <%= if @monitor.last_seen_at do %>
                    {Calendar.strftime(@monitor.last_seen_at, "%Y-%m-%d %H:%M UTC")}
                  <% else %>
                    <span class="opacity-50">Never</span>
                  <% end %>
                </dd>
              </div>
              <div class="flex justify-between">
                <dt class="opacity-70">Status</dt>
                <dd>
                  <span class={[
                    "badge badge-sm",
                    monitor_online?(@monitor) && "badge-success",
                    !monitor_online?(@monitor) && "badge-warning"
                  ]}>
                    {if monitor_online?(@monitor), do: "Online", else: "Offline"}
                  </span>
                </dd>
              </div>
            </dl>
          </div>
        </div>
      </div>

      <div class="card bg-base-200 shadow-sm mb-6">
        <div class="card-body">
          <h2 class="card-title text-sm">Configuration</h2>
          <p class="text-xs opacity-70 mb-3">Update what your monitor listens for.</p>
          <.form for={@form} id="config-form" phx-submit="update-config">
            <div class="grid grid-cols-2 gap-3">
              <.input field={@form[:name]} type="text" label="Name" required />
              <.input
                field={@form[:beacon_id]}
                type="select"
                label="Beacon to monitor"
                options={beacon_options(@beacons)}
                prompt="Select beacon"
              />
              <.input field={@form[:config_frequency_hz]} type="number" label="Frequency (Hz)" />
              <p class="text-xs opacity-60 -mt-2">Override — leave blank to use beacon's frequency</p>
              <.input field={@form[:config_integration_s]} type="number" label="Integration (s)" />
              <p class="text-xs opacity-60 -mt-2">Override — leave blank for default (60s)</p>
              <.input
                field={@form[:config_mode]}
                type="text"
                label="Mode"
                placeholder="e.g. wspr, q65a_30"
              />
            </div>
            <footer class="mt-4">
              <.button variant="primary" phx-disable-with="Saving...">Save</.button>
            </footer>
          </.form>
        </div>
      </div>

      <div class="card bg-base-200 shadow-sm">
        <div class="card-body">
          <h2 class="card-title text-sm mb-2">Recent measurements</h2>
          <%= if @measurements == [] do %>
            <p class="text-sm opacity-70">
              No measurements yet. Once the monitor starts reporting, they'll appear here.
            </p>
          <% else %>
            <div class="overflow-x-auto">
              <table class="table table-zebra table-sm">
                <thead>
                  <tr>
                    <th>Time</th>
                    <th>Frequency</th>
                    <th>SNR avg</th>
                    <th>SNR peak</th>
                    <th>Noise floor</th>
                    <th>Gain</th>
                    <th>Integration</th>
                  </tr>
                </thead>
                <tbody>
                  <tr :for={m <- @measurements}>
                    <td class="whitespace-nowrap text-xs">
                      {Calendar.strftime(m.measured_at, "%H:%M UTC")}
                    </td>
                    <td class="text-xs">{format_freq(m.frequency_hz)}</td>
                    <td class="text-xs">{Float.round(m.snr_avg_db, 1)} dB</td>
                    <td class="text-xs">{Float.round(m.snr_peak_db, 1)} dB</td>
                    <td class="text-xs">{Float.round(m.noise_floor_dbfs, 1)} dBFS</td>
                    <td class="text-xs">{Float.round(m.gain_db, 1)} dB</td>
                    <td class="text-xs">{m.integration_s}s</td>
                  </tr>
                </tbody>
              </table>
            </div>
          <% end %>
        </div>
      </div>
    </Layouts.app>
    """
  end

  @impl true
  def handle_event("update-config", %{"beacon_monitor" => params}, socket) do
    monitor = socket.assigns.monitor

    case BeaconMonitors.update_config(monitor, params) do
      {:ok, updated} ->
        {:noreply,
         socket
         |> assign(:monitor, updated)
         |> assign_form(updated)
         |> put_flash(:info, "Configuration updated.")}

      {:error, changeset} ->
        {:noreply, assign(socket, :form, to_form(changeset, as: :beacon_monitor))}
    end
  end

  defp monitor_online?(monitor) do
    monitor.last_seen_at && DateTime.diff(DateTime.utc_now(), monitor.last_seen_at, :minute) < 30
  end

  defp assign_form(socket, monitor) do
    assign(socket, :form, to_form(BeaconMonitor.config_changeset(monitor, %{}), as: :beacon_monitor))
  end

  defp beacon_options(beacons) do
    Enum.map(beacons, &{"#{&1.callsign} @ #{Beacon.format_freq(&1.frequency_mhz)} MHz", &1.id})
  end

  defp format_freq(hz) when is_integer(hz) and hz >= 1_000_000 do
    mhz =
      (hz / 1_000_000)
      |> Float.round(3)
      |> then(fn
        n when n == trunc(n) -> trunc(n)
        n -> n
      end)

    "#{mhz} MHz"
  end

  defp format_freq(hz) when is_integer(hz), do: "#{hz} Hz"
  defp format_freq(_), do: ""
end