prop/lib/microwaveprop_web/live/contact_live/show.ex

defmodule MicrowavepropWeb.ContactLive.Show do
  @moduledoc false
  use MicrowavepropWeb, :live_view

  require Logger

  alias Microwaveprop.Propagation.BandConfig
  alias Microwaveprop.Propagation.Scorer
  alias Microwaveprop.Radio
  alias Microwaveprop.Terrain
  alias Microwaveprop.Terrain.ElevationClient
  alias Microwaveprop.Terrain.TerrainAnalysis
  alias Microwaveprop.Weather
  alias Microwaveprop.Weather.HrrrClient
  alias Microwaveprop.Workers.HrrrFetchWorker
  alias Microwaveprop.Workers.TerrainProfileWorker

  @earth_radius_m 6_371_000.0

  @impl true
  def mount(%{"id" => id}, _session, socket) do
    contact = Radio.get_contact!(id)

    if connected?(socket) do
      Phoenix.PubSub.subscribe(Microwaveprop.PubSub, "contact_enrichment:#{contact.id}")
      Phoenix.PubSub.subscribe(Microwaveprop.PubSub, "contact_enrichment:hrrr")
    end

    weather = load_weather(contact)
    solar = load_solar(contact)
    hrrr_path = Weather.hrrr_profiles_for_path(contact)
    hrrr = List.first(hrrr_path)
    {hrrr, hrrr_status} = maybe_enqueue_hrrr(hrrr, contact)
    terrain = Terrain.get_terrain_profile(contact.id)
    maybe_enqueue_terrain(terrain, contact)
    elevation_profile = compute_elevation_profile(contact, hrrr_path, weather.soundings)
    propagation_analysis = build_propagation_analysis(contact, hrrr, terrain, elevation_profile, weather.soundings)

    {:ok,
     assign(socket,
       page_title: "#{contact.station1} / #{contact.station2}",
       contact: contact,
       surface_observations: weather.surface_observations,
       soundings: weather.soundings,
       solar: solar,
       hrrr: hrrr,
       hrrr_status: hrrr_status,
       terrain: terrain,
       elevation_profile: elevation_profile,
       propagation_analysis: propagation_analysis,
       terrain_expanded: false,
       hrrr_profile_expanded: false,
       obs_sort_by: "station_name",
       obs_sort_order: "asc",
       sounding_sort_by: "station_name",
       sounding_sort_order: "asc",
       expanded_soundings: MapSet.new()
     )}
  end

  @impl true
  def handle_event("sort", %{"field" => field, "table" => "obs"}, socket) do
    {sort_by, sort_order} =
      toggle_sort(socket.assigns.obs_sort_by, socket.assigns.obs_sort_order, field)

    sorted = sort_observations(socket.assigns.surface_observations, sort_by, sort_order)

    {:noreply,
     assign(socket,
       surface_observations: sorted,
       obs_sort_by: sort_by,
       obs_sort_order: sort_order
     )}
  end

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

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

  def handle_event("toggle_flag", _params, socket) do
    contact = Radio.toggle_flagged_invalid!(socket.assigns.contact)
    {:noreply, assign(socket, contact: contact)}
  end

  def handle_event("toggle_profile", %{"id" => id}, socket) do
    expanded =
      if MapSet.member?(socket.assigns.expanded_soundings, id) do
        MapSet.delete(socket.assigns.expanded_soundings, id)
      else
        MapSet.put(socket.assigns.expanded_soundings, id)
      end

    {:noreply, assign(socket, expanded_soundings: expanded)}
  end

  def handle_event("sort", %{"field" => field, "table" => "soundings"}, socket) do
    {sort_by, sort_order} =
      toggle_sort(socket.assigns.sounding_sort_by, socket.assigns.sounding_sort_order, field)

    sorted = sort_soundings(socket.assigns.soundings, sort_by, sort_order)

    {:noreply,
     assign(socket,
       soundings: sorted,
       sounding_sort_by: sort_by,
       sounding_sort_order: sort_order
     )}
  end

  @impl true
  def handle_info({:terrain_ready, _qso_id}, socket) do
    contact = socket.assigns.contact
    terrain = Terrain.get_terrain_profile(contact.id)
    soundings = socket.assigns.soundings
    hrrr_path = Weather.hrrr_profiles_for_path(contact)
    hrrr = List.first(hrrr_path)
    elevation_profile = compute_elevation_profile(contact, hrrr_path, soundings)
    propagation_analysis = build_propagation_analysis(contact, hrrr, terrain, elevation_profile, soundings)

    {:noreply,
     assign(socket,
       terrain: terrain,
       elevation_profile: elevation_profile,
       propagation_analysis: propagation_analysis
     )}
  end

  def handle_info({:hrrr_ready, _info}, socket) do
    contact = socket.assigns.contact
    hrrr_path = Weather.hrrr_profiles_for_path(contact)
    hrrr = List.first(hrrr_path)

    if hrrr do
      soundings = socket.assigns.soundings
      terrain = socket.assigns.terrain
      elevation_profile = compute_elevation_profile(contact, hrrr_path, soundings)
      propagation_analysis = build_propagation_analysis(contact, hrrr, terrain, elevation_profile, soundings)

      {:noreply,
       assign(socket,
         hrrr: hrrr,
         hrrr_status: :loaded,
         elevation_profile: elevation_profile,
         propagation_analysis: propagation_analysis
       )}
    else
      {:noreply, socket}
    end
  end

  defp toggle_sort(current_field, current_order, new_field) do
    if current_field == new_field && current_order == "asc",
      do: {new_field, "desc"},
      else: {new_field, "asc"}
  end

  defp sort_observations(observations, sort_by, sort_order) do
    sorter = obs_sort_key(sort_by)
    sorted = Enum.sort_by(observations, sorter)
    if sort_order == "desc", do: Enum.reverse(sorted), else: sorted
  end

  defp obs_sort_key("station_name"), do: fn obs -> obs.station.name || obs.station.station_code end
  defp obs_sort_key("observed_at"), do: & &1.observed_at
  defp obs_sort_key("temp_f"), do: &(&1.temp_f || 0)
  defp obs_sort_key("dewpoint_f"), do: &(&1.dewpoint_f || 0)
  defp obs_sort_key("relative_humidity"), do: &(&1.relative_humidity || 0)
  defp obs_sort_key("sea_level_pressure_mb"), do: &(&1.sea_level_pressure_mb || 0)
  defp obs_sort_key(_), do: fn obs -> obs.station.name || obs.station.station_code end

  defp sort_soundings(soundings, sort_by, sort_order) do
    sorter = sounding_sort_key(sort_by)
    sorted = Enum.sort_by(soundings, sorter)
    if sort_order == "desc", do: Enum.reverse(sorted), else: sorted
  end

  defp sounding_sort_key("station_name"), do: fn s -> s.station.name || s.station.station_code end

  defp sounding_sort_key("observed_at"), do: & &1.observed_at
  defp sounding_sort_key("surface_temp_c"), do: &(&1.surface_temp_c || 0)
  defp sounding_sort_key("surface_refractivity"), do: &(&1.surface_refractivity || 0)
  defp sounding_sort_key("k_index"), do: &(&1.k_index || 0)
  defp sounding_sort_key("lifted_index"), do: &(&1.lifted_index || 0)
  defp sounding_sort_key(_), do: fn s -> s.station.name || s.station.station_code end

  defp load_weather(contact) do
    lat1 = contact.pos1 && contact.pos1["lat"]
    lon1 = contact.pos1 && (contact.pos1["lon"] || contact.pos1["lng"])
    lat2 = contact.pos2 && contact.pos2["lat"]
    lon2 = contact.pos2 && (contact.pos2["lon"] || contact.pos2["lng"])

    if lat1 && lon1 do
      # Search along the path midpoint with radius covering both endpoints
      mid_lat = if lat2, do: (lat1 + lat2) / 2, else: lat1
      mid_lon = if lon2, do: (lon1 + lon2) / 2, else: lon1
      half_dist = if lat2 && lon2, do: haversine_km(lat1, lon1, lat2, lon2) / 2, else: 0
      radius = max(50, half_dist + 50)

      weather =
        Weather.weather_for_contact(
          %{lat: mid_lat, lon: mid_lon, timestamp: contact.qso_timestamp},
          radius_km: radius
        )

      # Keep only the 5 closest stations by distance to path midpoint
      %{
        surface_observations:
          weather.surface_observations
          |> Enum.sort_by(fn obs ->
            slat = obs.station.lat
            slon = obs.station.lon
            abs(slat - mid_lat) + abs(slon - mid_lon)
          end)
          |> Enum.take(5),
        soundings: weather.soundings
      }
    else
      %{surface_observations: [], soundings: []}
    end
  end

  defp maybe_enqueue_terrain(terrain, _contact) when not is_nil(terrain), do: :ok

  defp maybe_enqueue_terrain(nil, contact) do
    if contact.pos1 && contact.pos2 do
      Oban.insert(TerrainProfileWorker.new(%{"qso_id" => contact.id}))
    end

    :ok
  end

  defp maybe_enqueue_hrrr(hrrr, _contact) when not is_nil(hrrr), do: {hrrr, :loaded}

  defp maybe_enqueue_hrrr(nil, contact) do
    lat = contact.pos1 && contact.pos1["lat"]
    lon = contact.pos1 && (contact.pos1["lon"] || contact.pos1["lng"])

    if lat && lon do
      valid_time = HrrrClient.nearest_hrrr_hour(contact.qso_timestamp)
      {rlat, rlon} = Weather.round_to_hrrr_grid(lat, lon)

      Oban.insert(
        HrrrFetchWorker.new(%{
          "lat" => rlat,
          "lon" => rlon,
          "valid_time" => DateTime.to_iso8601(valid_time)
        })
      )

      {nil, :queued}
    else
      {nil, :unavailable}
    end
  end

  defp load_solar(contact) do
    contact.qso_timestamp
    |> DateTime.to_date()
    |> Weather.get_solar_index()
  end

  @impl true
  def render(assigns) do
    ~H"""
    <Layouts.app flash={@flash}>
      <.header>
        <span class={[@contact.flagged_invalid && "line-through opacity-50"]}>
          {@contact.station1} / {@contact.station2}
        </span>
        <:subtitle>
          {Calendar.strftime(@contact.qso_timestamp, "%Y-%m-%d %H:%M UTC")}
          <%= if @contact.flagged_invalid do %>
            <span class="badge badge-error badge-sm ml-2">Flagged Invalid</span>
          <% end %>
        </:subtitle>
        <:actions>
          <button
            phx-click="toggle_flag"
            class={[
              "btn btn-sm",
              if(@contact.flagged_invalid, do: "btn-warning", else: "btn-ghost")
            ]}
          >
            <.icon name="hero-flag" class="w-4 h-4" />
            {if @contact.flagged_invalid, do: "Unflag", else: "Flag as Invalid"}
          </button>
          <.link navigate={~p"/contacts"} class="btn btn-sm btn-ghost">
            <.icon name="hero-arrow-left" class="w-4 h-4" /> Back to Contacts
          </.link>
        </:actions>
      </.header>

      <%= if @contact.pos1 && @contact.pos2 do %>
        <p class="text-xs text-base-content/50 italic mb-1">
          Locations approximate, in the center of the grid squares
        </p>
        <div
          id="contact-map"
          phx-hook="ContactMap"
          phx-update="ignore"
          data-pos1={Jason.encode!(@contact.pos1)}
          data-pos2={Jason.encode!(@contact.pos2)}
          data-station1={@contact.station1}
          data-station2={@contact.station2}
          class="w-full h-64 rounded-lg border border-base-300 mb-4"
        />
      <% end %>

      <%= if @elevation_profile do %>
        <div class="mb-4">
          <div class="text-sm font-mono mb-2 text-center">
            {format_band_ghz(@contact.band)} &middot; {@contact.mode} &middot; {format_dist(
              @elevation_profile.dist_km
            )} &middot; {@contact.grid1 || "—"} &rarr; {@contact.grid2 || "—"}
          </div>
          <table class="text-sm font-mono mb-2 mx-auto">
            <tr>
              <td class="pr-6">{@contact.station1} &rarr; {@contact.station2}</td>
              <td class="pr-6">Az: {format_bearing(@elevation_profile.fwd_az)}</td>
              <td>El: {@elevation_profile.fwd_el}&deg;</td>
            </tr>
            <tr>
              <td class="pr-6">{@contact.station2} &rarr; {@contact.station1}</td>
              <td class="pr-6">Az: {format_bearing(@elevation_profile.rev_az)}</td>
              <td>El: {@elevation_profile.rev_el}&deg;</td>
            </tr>
          </table>

          <%= if @elevation_profile.verdict == "BLOCKED" && @elevation_profile.first_obstruction_km do %>
            <div class="bg-error/10 text-error font-semibold px-3 py-1 rounded mb-2 text-sm">
              Obstructed at {format_dist(@elevation_profile.first_obstruction_km)}
            </div>
          <% end %>
          <%= if @elevation_profile.verdict == "CLEAR" do %>
            <div class="bg-success/10 text-success font-semibold px-3 py-1 rounded mb-2 text-sm">
              Line of sight clear
            </div>
          <% end %>

          <div
            id="elevation-profile"
            phx-hook="ElevationProfile"
            phx-update="ignore"
            data-profile={Jason.encode!(@elevation_profile)}
            class="w-full h-96 border border-base-300 rounded-lg"
          >
            <canvas></canvas>
          </div>
        </div>
      <% end %>

      <%= if @propagation_analysis do %>
        <div class="divider" />

        <h2 class="text-base font-semibold mb-2">Propagation Analysis</h2>
        <div class="text-sm mb-3">
          <p>{@propagation_analysis.summary}</p>
          <%= for detail <- @propagation_analysis.details do %>
            <p class="mt-1 text-base-content/70">{detail}</p>
          <% end %>
        </div>

        <%= if @propagation_analysis.factors do %>
          <div class="overflow-x-auto mb-2">
            <table class="table table-xs table-zebra">
              <thead>
                <tr>
                  <th>Factor</th>
                  <th>Score</th>
                  <th>Weight</th>
                  <th>Contribution</th>
                  <th>Notes</th>
                </tr>
              </thead>
              <tbody>
                <%= for f <- @propagation_analysis.factor_rows do %>
                  <tr>
                    <td class="font-semibold">{f.name}</td>
                    <td>{f.score}/100</td>
                    <td>{f.weight}%</td>
                    <td>{f.contribution}</td>
                    <td class="text-base-content/60">{f.note}</td>
                  </tr>
                <% end %>
              </tbody>
              <tfoot>
                <tr class="font-semibold">
                  <td>Composite</td>
                  <td colspan="2">{@propagation_analysis.composite_score}/100</td>
                  <td colspan="2">
                    <span class={propagation_tier_class(@propagation_analysis.composite_score)}>
                      {propagation_tier_label(@propagation_analysis.composite_score)}
                    </span>
                  </td>
                </tr>
              </tfoot>
            </table>
          </div>
        <% end %>
      <% end %>

      <div class="divider" />

      <h2 class="text-base font-semibold mb-2" id="terrain-heading">Terrain Profile</h2>
      <%= if @terrain do %>
        <div class="mb-6 border border-base-300 rounded-lg" id="terrain-profile">
          <button
            phx-click="toggle_terrain"
            class="w-full flex items-center justify-between p-4 hover:bg-base-200 transition-colors"
          >
            <div class="flex items-center gap-4 text-sm flex-wrap">
              <span class={[
                "badge badge-sm",
                terrain_verdict_class(@terrain.verdict)
              ]}>
                {@terrain.verdict}
              </span>
              <span>{@terrain.sample_count} samples</span>
              <span>Max elev: {format_number(@terrain.max_elevation_m)} m</span>
              <span>Min clearance: {format_number(@terrain.min_clearance_m)} m</span>
              <%= if @terrain.diffraction_db && @terrain.diffraction_db > 0 do %>
                <span>Diffraction: {format_number(@terrain.diffraction_db)} dB</span>
              <% end %>
              <%= if @terrain.obstructed_count && @terrain.obstructed_count > 0 do %>
                <span class="text-error">{@terrain.obstructed_count} obstructed</span>
              <% end %>
              <%= if @terrain.fresnel_hit_count && @terrain.fresnel_hit_count > 0 do %>
                <span class="text-warning">{@terrain.fresnel_hit_count} Fresnel hits</span>
              <% end %>
            </div>
            <.icon
              name={if @terrain_expanded, do: "hero-chevron-up", else: "hero-chevron-down"}
              class="w-5 h-5"
            />
          </button>

          <%= if @terrain_expanded do %>
            <div class="px-4 pb-4">
              <div class="overflow-x-auto">
                <table class="table table-xs table-zebra">
                  <thead>
                    <tr>
                      <th>#</th>
                      <th>Lat</th>
                      <th>Lon</th>
                      <th>Dist (km)</th>
                      <th>Elev (m)</th>
                    </tr>
                  </thead>
                  <tbody>
                    <%= for {pt, idx} <- Enum.with_index(@terrain.path_points) do %>
                      <tr>
                        <td>{idx}</td>
                        <td>{format_number(pt["lat"])}</td>
                        <td>{format_number(pt["lon"])}</td>
                        <td>{format_number(pt["dist_km"])}</td>
                        <td>{format_number(pt["elev"])}</td>
                      </tr>
                    <% end %>
                  </tbody>
                </table>
              </div>
            </div>
          <% end %>
        </div>
      <% else %>
        <p class="text-sm text-base-content/50 italic">No terrain profile available.</p>
      <% end %>

      <div class="divider" />

      <h2 class="text-base font-semibold mb-2">Soundings</h2>
      <%= if @soundings == [] do %>
        <p class="text-sm text-base-content/50 italic">No soundings found nearby.</p>
      <% else %>
        <%= for s <- @soundings do %>
          <div class="mb-6 border border-base-300 rounded-lg">
            <button
              phx-click="toggle_profile"
              phx-value-id={s.id}
              class="w-full flex items-center justify-between p-4 hover:bg-base-200 transition-colors"
            >
              <div class="flex items-center gap-4 text-sm">
                <span class="font-semibold">{s.station.name || s.station.station_code}</span>
                <span>{Calendar.strftime(s.observed_at, "%H:%M UTC")}</span>
                <span>{s.level_count} levels</span>
                <span>Sfc: {format_number(s.surface_temp_c)}°C</span>
                <span>N: {format_number(s.surface_refractivity)}</span>
                <span>K: {format_number(s.k_index)}</span>
                <span>LI: {format_number(s.lifted_index)}</span>
                <%= if s.ducting_detected do %>
                  <span class="badge badge-warning badge-sm">Ducting</span>
                <% end %>
              </div>
              <.icon
                name={
                  if MapSet.member?(@expanded_soundings, s.id),
                    do: "hero-chevron-up",
                    else: "hero-chevron-down"
                }
                class="w-5 h-5"
              />
            </button>

            <%= if MapSet.member?(@expanded_soundings, s.id) do %>
              <div class="px-4 pb-4">
                <div class="overflow-x-auto">
                  <table class="table table-xs table-zebra">
                    <thead>
                      <tr>
                        <th>Pressure (mb)</th>
                        <th>Height (m)</th>
                        <th>Temp (°C)</th>
                        <th>Dewpoint (°C)</th>
                        <th>Wind Dir (°)</th>
                        <th>Wind Spd (kts)</th>
                      </tr>
                    </thead>
                    <tbody>
                      <%= for level <- filter_profile(s.profile) do %>
                        <tr>
                          <td>{format_number(level["pres"])}</td>
                          <td>{format_number(level["hght"])}</td>
                          <td>{format_number(level["tmpc"])}</td>
                          <td>{format_number(level["dwpc"])}</td>
                          <td>{format_number(level["drct"])}</td>
                          <td>{format_number(level["sknt"])}</td>
                        </tr>
                      <% end %>
                    </tbody>
                  </table>
                </div>
              </div>
            <% end %>
          </div>
        <% end %>
      <% end %>

      <div class="divider" />

      <h2 class="text-base font-semibold mb-2">Solar Conditions</h2>
      <%= if @solar do %>
        <div class="flex flex-wrap gap-x-6 gap-y-1 text-sm">
          <div><span class="font-semibold">SFI:</span> {@solar.sfi || "—"}</div>
          <div><span class="font-semibold">Sunspot #:</span> {@solar.sunspot_number || "—"}</div>
          <div><span class="font-semibold">Ap:</span> {@solar.ap_index || "—"}</div>
          <div><span class="font-semibold">Kp:</span> {format_kp(@solar.kp_values)}</div>
        </div>
      <% else %>
        <p class="text-sm text-base-content/50 italic">No solar data available for this date.</p>
      <% end %>

      <div class="divider" />

      <h2 class="text-base font-semibold mb-2">HRRR Model Profile</h2>
      <%= if @hrrr do %>
        <div class="mb-6 border border-base-300 rounded-lg">
          <button
            phx-click="toggle_hrrr_profile"
            class="w-full flex items-center justify-between p-4 hover:bg-base-200 transition-colors"
          >
            <div class="flex items-center gap-4 text-sm">
              <span class="font-semibold">
                {format_number(@hrrr.lat)}°, {format_number(@hrrr.lon)}°
              </span>
              <span>{Calendar.strftime(@hrrr.valid_time, "%H:%M UTC")}</span>
              <span>HPBL: {format_number(@hrrr.hpbl_m)} m</span>
              <span>PWAT: {format_number(@hrrr.pwat_mm)} mm</span>
              <span>N: {format_number(@hrrr.surface_refractivity)}</span>
              <span>dN/dh: {format_number(@hrrr.min_refractivity_gradient)}</span>
              <%= if @hrrr.ducting_detected do %>
                <span class="badge badge-warning badge-sm">Ducting</span>
              <% end %>
            </div>
            <.icon
              name={if @hrrr_profile_expanded, do: "hero-chevron-up", else: "hero-chevron-down"}
              class="w-5 h-5"
            />
          </button>

          <%= if @hrrr_profile_expanded do %>
            <div class="px-4 pb-4">
              <div class="grid grid-cols-2 gap-x-8 gap-y-1 text-sm mb-4">
                <div>Surface Temp: {format_number(@hrrr.surface_temp_c)}°C</div>
                <div>Surface Dewpoint: {format_number(@hrrr.surface_dewpoint_c)}°C</div>
                <div>Surface Pressure: {format_number(@hrrr.surface_pressure_mb)} mb</div>
                <div>
                  Run Time: {if @hrrr.run_time,
                    do: Calendar.strftime(@hrrr.run_time, "%Y-%m-%d %H:%M UTC"),
                    else: "—"}
                </div>
              </div>
              <%= if @hrrr.profile && @hrrr.profile != [] do %>
                <div class="overflow-x-auto">
                  <table class="table table-xs table-zebra">
                    <thead>
                      <tr>
                        <th>Pressure (mb)</th>
                        <th>Height (m)</th>
                        <th>Temp (°C)</th>
                        <th>Dewpoint (°C)</th>
                      </tr>
                    </thead>
                    <tbody>
                      <%= for level <- @hrrr.profile do %>
                        <tr>
                          <td>{format_number(level["pres"])}</td>
                          <td>{format_number(level["hght"])}</td>
                          <td>{format_number(level["tmpc"])}</td>
                          <td>{format_number(level["dwpc"])}</td>
                        </tr>
                      <% end %>
                    </tbody>
                  </table>
                </div>
              <% end %>
            </div>
          <% end %>
        </div>
      <% else %>
        <p class="text-sm text-base-content/50 italic">
          <%= case @hrrr_status do %>
            <% :queued -> %>
              HRRR fetch queued — reload in a few minutes.
            <% :unavailable -> %>
              HRRR data unavailable for this contact time.
            <% _ -> %>
              No HRRR profile available.
          <% end %>
        </p>
      <% end %>

      <div class="divider" />

      <h2 class="text-base font-semibold mb-2">Surface Observations</h2>
      <%= if @surface_observations == [] do %>
        <p class="text-sm text-base-content/50 italic">No surface observations found nearby.</p>
      <% else %>
        <div class="overflow-x-auto">
          <table class="table table-xs table-zebra">
            <thead>
              <tr>
                <th>Station</th>
                <th>Time</th>
                <th>Temp</th>
                <th>Dewpt</th>
                <th>RH%</th>
                <th>Wind</th>
                <th>Pres (mb)</th>
                <th>Sky</th>
              </tr>
            </thead>
            <tbody>
              <%= for obs <- @surface_observations do %>
                <tr>
                  <td>{obs.station.name || obs.station.station_code}</td>
                  <td>{Calendar.strftime(obs.observed_at, "%H:%M")}</td>
                  <td>{obs.temp_f || "—"}</td>
                  <td>{obs.dewpoint_f || "—"}</td>
                  <td>{format_number(obs.relative_humidity)}</td>
                  <td>{format_wind(obs)}</td>
                  <td>{obs.sea_level_pressure_mb || "—"}</td>
                  <td>{obs.sky_condition || "—"}</td>
                </tr>
              <% end %>
            </tbody>
          </table>
        </div>
      <% end %>
    </Layouts.app>
    """
  end

  defp format_number(nil), do: "—"
  defp format_number(n) when is_float(n), do: :erlang.float_to_binary(n, decimals: 1)
  defp format_number(n), do: to_string(n)

  defp format_dist(km) do
    mi = km * 0.621371
    "#{:erlang.float_to_binary(mi, decimals: 1)} mi (#{:erlang.float_to_binary(km, decimals: 1)} km)"
  end

  defp format_bearing(deg) do
    whole = trunc(deg)
    frac = round((deg - whole) * 10)
    "#{String.pad_leading(to_string(whole), 3, "0")}.#{frac}\u00B0"
  end

  defp format_band_ghz(nil), do: "—"

  defp format_band_ghz(band) do
    mhz = Decimal.to_float(band)
    ghz = mhz / 1000

    if ghz == Float.round(ghz, 0) do
      "#{trunc(ghz)} GHz"
    else
      "#{:erlang.float_to_binary(ghz, decimals: 1)} GHz"
    end
  end

  defp format_wind(obs) do
    case {obs.wind_direction_deg, obs.wind_speed_kts} do
      {nil, nil} -> "—"
      {dir, speed} -> "#{dir || "?"}° @ #{speed || "?"} kts"
    end
  end

  defp filter_profile(profile) do
    Enum.filter(profile, fn level ->
      level["tmpc"] != nil || level["dwpc"] != nil
    end)
  end

  defp format_kp(nil), do: "—"
  defp format_kp(values) when is_list(values), do: Enum.map_join(values, ", ", &format_number/1)

  defp terrain_verdict_class("CLEAR"), do: "badge-success"
  defp terrain_verdict_class("FRESNEL_MINOR"), do: "badge-warning"
  defp terrain_verdict_class("FRESNEL_PARTIAL"), do: "badge-warning"
  defp terrain_verdict_class("BLOCKED"), do: "badge-error"
  defp terrain_verdict_class(_), do: "badge-ghost"

  defp compute_elevation_profile(contact, hrrr_path, soundings) do
    with %{"lat" => lat1} <- contact.pos1,
         lon1 when is_number(lon1) <- contact.pos1["lon"] || contact.pos1["lng"],
         %{"lat" => lat2} <- contact.pos2,
         lon2 when is_number(lon2) <- contact.pos2["lon"] || contact.pos2["lng"],
         {:ok, profile} <- safe_fetch_elevation(lat1, lon1, lat2, lon2) do
      freq_ghz = band_to_ghz(contact.band)
      dist_km = haversine_km(lat1, lon1, lat2, lon2)
      analysis = TerrainAnalysis.analyse(profile, dist_km, freq_ghz)

      fwd_az = initial_bearing(lat1, lon1, lat2, lon2)
      rev_az = initial_bearing(lat2, lon2, lat1, lon1)

      tx_elev = hd(profile).elev
      rx_elev = List.last(profile).elev
      fwd_el = elevation_angle(tx_elev, rx_elev, dist_km * 1000)
      rev_el = elevation_angle(rx_elev, tx_elev, dist_km * 1000)

      first_obs =
        case Enum.find(analysis.points, & &1.obstructed) do
          nil -> nil
          p -> p.dist_km
        end

      ducts =
        hrrr_path
        |> extract_ducts(soundings, tx_elev)
        |> merge_nearby_ducts()
        |> Enum.sort_by(& &1.strength, :desc)
        |> Enum.take(3)
        |> mark_likely_duct(tx_elev, rx_elev)

      %{
        points:
          Enum.map(analysis.points, fn p ->
            %{elev: p.elev, beam: p.beam, r1: p.r1, dist_km: p.dist_km}
          end),
        freq_mhz: freq_ghz * 1000,
        dist_km: dist_km,
        fwd_az: fwd_az,
        rev_az: rev_az,
        fwd_el: fwd_el,
        rev_el: rev_el,
        verdict: analysis.verdict,
        first_obstruction_km: first_obs,
        ducts: ducts
      }
    else
      _ -> nil
    end
  end

  # Extract duct layers from best available source across all HRRR path profiles:
  # 1. HRRR explicit ducts (M-profile detected) from any path point
  # 2. Sounding explicit ducts (high vertical resolution, most reliable)
  # 3. Inferred from strongest HRRR refractivity gradient along path
  defp extract_ducts(hrrr_path, soundings, surface_elev) do
    hrrr_ducts = extract_hrrr_ducts(hrrr_path, surface_elev)

    if hrrr_ducts == [] do
      sounding_ducts = extract_sounding_ducts(soundings, surface_elev)

      if sounding_ducts == [] do
        # Use the profile with the strongest (most negative) gradient
        best =
          hrrr_path
          |> Enum.filter(&is_number(&1.min_refractivity_gradient))
          |> Enum.min_by(& &1.min_refractivity_gradient, fn -> nil end)

        infer_duct_from_gradient(best, surface_elev)
      else
        sounding_ducts
      end
    else
      hrrr_ducts
    end
  end

  defp extract_hrrr_ducts(hrrr_path, surface_elev) when is_list(hrrr_path) do
    hrrr_path
    |> Enum.flat_map(fn h ->
      case h.duct_characteristics do
        ducts when is_list(ducts) and ducts != [] ->
          Enum.map(ducts, fn d ->
            %{
              base_m_msl: surface_elev + (d["base"] || 0),
              top_m_msl: surface_elev + (d["top"] || 0),
              strength: d["strength"],
              source: "hrrr"
            }
          end)

        _ ->
          []
      end
    end)
    |> Enum.uniq_by(fn d -> {round(d.base_m_msl), round(d.top_m_msl)} end)
  end

  defp extract_sounding_ducts(soundings, surface_elev) when is_list(soundings) do
    soundings
    |> Enum.filter(& &1.ducting_detected)
    |> Enum.flat_map(fn s ->
      case s.duct_characteristics do
        ducts when is_list(ducts) and ducts != [] ->
          Enum.map(ducts, fn d ->
            %{
              base_m_msl: surface_elev + (d["base"] || 0),
              top_m_msl: surface_elev + (d["top"] || 0),
              strength: d["strength"],
              source: "sounding"
            }
          end)

        _ ->
          []
      end
    end)
    |> Enum.uniq_by(fn d -> {round(d.base_m_msl), round(d.top_m_msl)} end)
  end

  defp extract_sounding_ducts(_, _), do: []

  # HRRR pressure levels are too coarse (~250m) to detect thin ducting layers
  # via the M-profile method. When min_refractivity_gradient indicates enhanced
  # propagation, infer a duct layer within the boundary layer.
  defp infer_duct_from_gradient(nil, _surface_elev), do: []

  defp infer_duct_from_gradient(hrrr, surface_elev) do
    grad = hrrr.min_refractivity_gradient
    hpbl = hrrr.hpbl_m

    if is_number(grad) and grad < -100 and is_number(hpbl) and hpbl > 0 do
      duct_top = min(hpbl * 0.6, 500)
      strength = abs(grad) / 10

      [
        %{
          base_m_msl: surface_elev,
          top_m_msl: surface_elev + duct_top,
          strength: Float.round(strength, 1),
          source: "inferred"
        }
      ]
    else
      []
    end
  end

  # Merge duct layers that overlap or are within 100m of each other
  defp merge_nearby_ducts(ducts) do
    ducts
    |> Enum.sort_by(& &1.base_m_msl)
    |> Enum.reduce([], fn duct, acc ->
      case acc do
        [prev | rest] when duct.base_m_msl <= prev.top_m_msl + 100 ->
          merged = %{
            prev
            | top_m_msl: max(prev.top_m_msl, duct.top_m_msl),
              strength: max(prev.strength, duct.strength)
          }

          [merged | rest]

        _ ->
          [duct | acc]
      end
    end)
    |> Enum.reverse()
  end

  # Mark the duct most likely carrying the signal. The signal enters at
  # surface level from each end, so the duct whose base is closest to
  # the average endpoint elevation is the most probable propagation path.
  defp mark_likely_duct([], _tx_elev, _rx_elev), do: []

  defp mark_likely_duct(ducts, tx_elev, rx_elev) do
    avg_elev = (tx_elev + rx_elev) / 2

    {likely_idx, _} =
      ducts
      |> Enum.with_index()
      |> Enum.min_by(fn {d, _idx} ->
        # Distance from average endpoint elevation to the duct layer
        # Prefer ducts that the endpoints are actually inside of
        if avg_elev >= d.base_m_msl and avg_elev <= d.top_m_msl do
          -d.strength
        else
          min(abs(d.base_m_msl - avg_elev), abs(d.top_m_msl - avg_elev))
        end
      end)

    Enum.with_index(ducts, fn d, i ->
      Map.put(d, :likely, i == likely_idx)
    end)
  end

  defp safe_fetch_elevation(lat1, lon1, lat2, lon2) do
    ElevationClient.fetch_elevation_profile(lat1, lon1, lat2, lon2, 256)
  rescue
    e ->
      Logger.warning("Elevation profile failed: #{Exception.message(e)}")
      {:error, :elevation_unavailable}
  end

  defp band_to_ghz(nil), do: 10.0

  defp band_to_ghz(band) do
    band
    |> Decimal.to_float()
    |> Kernel./(1000)
  end

  defp haversine_km(lat1, lon1, lat2, lon2) do
    dlat = deg_to_rad(lat2 - lat1)
    dlon = deg_to_rad(lon2 - lon1)
    rlat1 = deg_to_rad(lat1)
    rlat2 = deg_to_rad(lat2)

    a =
      :math.sin(dlat / 2) ** 2 +
        :math.cos(rlat1) * :math.cos(rlat2) * :math.sin(dlon / 2) ** 2

    2 * 6371.0 * :math.asin(:math.sqrt(a))
  end

  defp initial_bearing(lat1, lon1, lat2, lon2) do
    rlat1 = deg_to_rad(lat1)
    rlat2 = deg_to_rad(lat2)
    dlon = deg_to_rad(lon2 - lon1)

    y = :math.sin(dlon) * :math.cos(rlat2)

    x =
      :math.cos(rlat1) * :math.sin(rlat2) -
        :math.sin(rlat1) * :math.cos(rlat2) * :math.cos(dlon)

    bearing = y |> :math.atan2(x) |> rad_to_deg()
    Float.round(rem_float(bearing + 360, 360), 1)
  end

  defp elevation_angle(h_tx, h_rx, dist_m) do
    k_r = 4 / 3 * @earth_radius_m
    angle = :math.atan2(h_rx - h_tx, dist_m) - dist_m / (2 * k_r)
    Float.round(rad_to_deg(angle), 2)
  end

  defp deg_to_rad(deg), do: deg * :math.pi() / 180
  defp rad_to_deg(rad), do: rad * 180 / :math.pi()
  defp rem_float(a, b), do: a - Float.floor(a / b) * b

  # ── Propagation analysis ──────────────────────────────────────────

  defp build_propagation_analysis(contact, hrrr, terrain, elevation_profile, soundings) do
    band_mhz = if contact.band, do: Decimal.to_integer(contact.band), else: 10_000
    band_config = BandConfig.get(band_mhz) || BandConfig.get(10_000)
    dist_km = contact.distance_km && Decimal.to_float(contact.distance_km)

    {factors, factor_rows, composite} = compute_factors(hrrr, contact, band_config)
    summary = build_summary(terrain, elevation_profile, hrrr, soundings, dist_km, band_mhz)
    details = build_details(hrrr, soundings, elevation_profile, band_mhz)

    %{
      summary: summary,
      details: details,
      factors: factors,
      factor_rows: factor_rows,
      composite_score: composite
    }
  end

  defp compute_factors(nil, _contact, _band_config) do
    {nil, [], nil}
  end

  defp compute_factors(hrrr, contact, band_config) do
    lon = contact.pos1["lon"] || contact.pos1["lng"]
    temp_c = hrrr.surface_temp_c
    dewpoint_c = hrrr.surface_dewpoint_c

    if is_nil(temp_c) or is_nil(dewpoint_c) do
      {nil, [], nil}
    else
      temp_f = Scorer.c_to_f(temp_c)
      dewpoint_f = Scorer.c_to_f(dewpoint_c)

      conditions = %{
        abs_humidity: Scorer.absolute_humidity(temp_c, dewpoint_c),
        temp_f: temp_f,
        dewpoint_f: dewpoint_f,
        wind_speed_kts: nil,
        sky_cover_pct: nil,
        utc_hour: contact.qso_timestamp.hour,
        utc_minute: contact.qso_timestamp.minute,
        month: contact.qso_timestamp.month,
        longitude: lon,
        pressure_mb: hrrr.surface_pressure_mb,
        prev_pressure_mb: nil,
        rain_rate_mmhr: 0.0,
        min_refractivity_gradient: hrrr.min_refractivity_gradient,
        bl_depth_m: hrrr.hpbl_m,
        pwat_mm: hrrr.pwat_mm
      }

      result = Scorer.composite_score(conditions, band_config)
      weights = BandConfig.weights()

      factor_rows =
        [
          {:humidity, "Humidity", humidity_note(conditions.abs_humidity, band_config)},
          {:time_of_day, "Time of Day", time_note(contact.qso_timestamp, lon)},
          {:td_depression, "T-Td Depression", td_note(temp_f, dewpoint_f)},
          {:refractivity, "Refractivity", refractivity_note(hrrr.min_refractivity_gradient)},
          {:sky, "Sky Cover", sky_note(conditions.sky_cover_pct)},
          {:season, "Season", season_note(contact.qso_timestamp.month, band_config)},
          {:wind, "Wind", wind_note(conditions.wind_speed_kts)},
          {:rain, "Rain", rain_note(conditions.rain_rate_mmhr)},
          {:pwat, "PWAT", pwat_note(hrrr.pwat_mm, band_config)},
          {:pressure, "Pressure", pressure_note(hrrr.surface_pressure_mb)}
        ]
        |> Enum.map(fn {key, name, note} ->
          score = result.factors[key]
          weight = weights[key]

          %{
            name: name,
            score: score,
            weight: round(weight * 100),
            contribution: Float.round(score * weight, 1),
            note: note
          }
        end)
        |> Enum.sort_by(& &1.contribution, :desc)

      {result.factors, factor_rows, result.score}
    end
  end

  defp build_summary(terrain, elevation_profile, hrrr, soundings, dist_km, band_mhz) do
    terrain_status = terrain_summary(terrain, elevation_profile)
    mechanism = propagation_mechanism(terrain, elevation_profile, hrrr, soundings, dist_km)
    band_note = band_summary(band_mhz, hrrr)

    [terrain_status, mechanism, band_note]
    |> Enum.reject(&is_nil/1)
    |> Enum.join(" ")
  end

  defp terrain_summary(nil, nil), do: "No terrain data available."

  defp terrain_summary(terrain, elevation_profile) do
    verdict = (elevation_profile && elevation_profile.verdict) || (terrain && terrain.verdict)

    case verdict do
      "CLEAR" ->
        "Line of sight is clear between stations."

      "FRESNEL_MINOR" ->
        "Line of sight is clear but with minor Fresnel zone encroachment."

      "FRESNEL_PARTIAL" ->
        "Line of sight has partial Fresnel zone obstruction."

      "BLOCKED" ->
        obs_dist = elevation_profile && elevation_profile.first_obstruction_km

        if obs_dist do
          "Path is terrain-obstructed at #{:erlang.float_to_binary(obs_dist * 0.621371, decimals: 1)} mi (#{:erlang.float_to_binary(obs_dist, decimals: 1)} km) from station 1."
        else
          "Path is terrain-obstructed."
        end

      _ ->
        nil
    end
  end

  defp propagation_mechanism(terrain, elevation_profile, hrrr, soundings, dist_km) do
    blocked? = terrain && terrain.verdict == "BLOCKED"
    ducting? = has_ducting?(hrrr, soundings)

    enhanced_refraction? =
      hrrr != nil && is_number(hrrr.min_refractivity_gradient) && hrrr.min_refractivity_gradient < -100

    long_path? = dist_km && dist_km > 100

    ducts = (elevation_profile && elevation_profile.ducts) || []
    likely_duct = Enum.find(ducts, & &1[:likely])

    cond do
      blocked? && ducting? && likely_duct ->
        "Signal likely propagated via atmospheric ducting (#{duct_description(likely_duct)}), bending over the terrain obstruction."

      blocked? && ducting? ->
        "Ducting conditions detected — signal likely propagated through a tropospheric duct, bypassing the terrain obstruction."

      blocked? && enhanced_refraction? ->
        grad = round(hrrr.min_refractivity_gradient)

        "Enhanced refraction (dN/dh = #{grad} N-units/km) likely bent the signal over the obstruction. Conditions are super-refractive but below full ducting threshold."

      blocked? ->
        diff_db = terrain && terrain.diffraction_db

        if diff_db && diff_db > 0 do
          "Path is obstructed with #{:erlang.float_to_binary(diff_db, decimals: 1)} dB diffraction loss. Contact may have been enabled by knife-edge diffraction or tropospheric scatter."
        else
          "Path is obstructed. Contact likely enabled by tropospheric scatter or transient ducting conditions."
        end

      ducting? && long_path? && likely_duct ->
        "Ducting conditions present (#{duct_description(likely_duct)}) — likely extending range beyond normal line of sight."

      ducting? && long_path? ->
        "Ducting conditions present — likely contributing to extended range."

      enhanced_refraction? && long_path? ->
        "Enhanced refraction present — may have contributed to extended range."

      true ->
        nil
    end
  end

  defp duct_description(%{source: source, base_m_msl: base, top_m_msl: top, strength: strength}) do
    base_ft = round(base * 3.28084)
    top_ft = round(top * 3.28084)

    src =
      case source do
        "sounding" -> "sounding-detected"
        "inferred" -> "estimated"
        _ -> "detected"
      end

    "#{src} layer at #{base_ft}-#{top_ft} ft, #{strength} M-units"
  end

  defp duct_description(_), do: "detected layer"

  defp has_ducting?(hrrr, soundings) do
    hrrr_ducting = hrrr && hrrr.ducting_detected
    sounding_ducting = is_list(soundings) && Enum.any?(soundings, & &1.ducting_detected)
    hrrr_ducting || sounding_ducting
  end

  defp band_summary(band_mhz, hrrr) when band_mhz <= 12_000 do
    if hrrr && is_number(hrrr.pwat_mm) && hrrr.pwat_mm > 20 do
      "At 10 GHz, the elevated moisture (PWAT #{:erlang.float_to_binary(hrrr.pwat_mm, decimals: 1)} mm) enhances refractivity and ducting potential."
    end
  end

  defp band_summary(band_mhz, hrrr) when band_mhz >= 24_000 do
    if hrrr && is_number(hrrr.pwat_mm) && hrrr.pwat_mm > 25 do
      "At #{round(band_mhz / 1000)} GHz, high moisture (PWAT #{:erlang.float_to_binary(hrrr.pwat_mm, decimals: 1)} mm) causes significant water vapor absorption."
    end
  end

  defp band_summary(_, _), do: nil

  defp build_details(hrrr, soundings, elevation_profile, _band_mhz) do
    details = []

    details =
      if hrrr && is_number(hrrr.min_refractivity_gradient) do
        grad = round(hrrr.min_refractivity_gradient)

        label =
          cond do
            grad < -157 -> "ducting"
            grad < -100 -> "super-refractive"
            grad < -79 -> "enhanced"
            true -> "normal"
          end

        details ++ ["Refractivity gradient: #{grad} N-units/km (#{label})."]
      else
        details
      end

    details =
      if hrrr && is_number(hrrr.hpbl_m) do
        hpbl = round(hrrr.hpbl_m)
        note = if hpbl < 300, do: " — shallow boundary layer favors ducting", else: ""
        details ++ ["Boundary layer depth: #{hpbl} m#{note}."]
      else
        details
      end

    ducting_soundings = if is_list(soundings), do: Enum.filter(soundings, & &1.ducting_detected), else: []

    details =
      if ducting_soundings == [] do
        details
      else
        names = Enum.map_join(ducting_soundings, ", ", fn s -> s.station.name || s.station.station_code end)
        details ++ ["Ducting detected by soundings at: #{names}."]
      end

    details =
      if elevation_profile do
        ducts = elevation_profile.ducts || []
        likely = Enum.find(ducts, & &1[:likely])

        if likely do
          details ++ ["Most likely propagation duct: #{duct_description(likely)}."]
        else
          details
        end
      else
        details
      end

    details
  end

  # Factor note helpers
  defp humidity_note(abs_h, band_config) do
    h = Float.round(abs_h, 1)
    effect = if band_config.humidity_effect == :beneficial, do: "beneficial", else: "harmful"
    "#{h} g/m³ (#{effect} at this band)"
  end

  defp time_note(ts, lon) do
    solar_hour = ts.hour + ts.minute / 60 + (lon || 0) / 15
    solar_hour = rem_float(solar_hour + 24, 24)
    h = round(solar_hour)

    label =
      cond do
        h >= 4 and h < 8 -> "dawn"
        h >= 8 and h < 12 -> "morning"
        h >= 12 and h < 17 -> "afternoon"
        h >= 17 and h < 21 -> "evening"
        true -> "night"
      end

    "Solar hour ~#{h} (#{label})"
  end

  defp td_note(temp_f, dewpoint_f) when is_number(temp_f) and is_number(dewpoint_f) do
    depression = Float.round(temp_f - dewpoint_f, 1)

    label =
      cond do
        depression < 3 -> "near saturation"
        depression < 8 -> "moist"
        depression < 15 -> "moderate"
        true -> "dry"
      end

    "T-Td = #{depression}°F (#{label})"
  end

  defp td_note(_, _), do: "—"

  defp refractivity_note(nil), do: "—"

  defp refractivity_note(grad) do
    g = round(grad)

    label =
      cond do
        g < -157 -> "ducting"
        g < -100 -> "super-refractive"
        g < -79 -> "enhanced"
        true -> "normal"
      end

    "dN/dh = #{g} (#{label})"
  end

  defp sky_note(nil), do: "—"
  defp sky_note(pct), do: "#{round(pct)}% cloud cover"

  defp season_note(month, band_config) do
    month_names = ~w(Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec)
    name = Enum.at(month_names, month - 1)
    effect = if band_config.humidity_effect == :beneficial, do: "summer peak", else: "winter peak"
    "#{name} (#{effect} band)"
  end

  defp wind_note(nil), do: "—"

  defp wind_note(kts) do
    k = Float.round(kts, 1)

    label =
      cond do
        k < 5 -> "calm"
        k < 15 -> "light"
        k < 25 -> "moderate"
        true -> "strong"
      end

    "#{k} kts (#{label})"
  end

  defp rain_note(rate) when rate > 0, do: "#{Float.round(rate, 1)} mm/hr"
  defp rain_note(_), do: "None"

  defp pwat_note(nil, _), do: "—"

  defp pwat_note(mm, band_config) do
    effect = if band_config.humidity_effect == :beneficial, do: "refractivity aid", else: "absorption"
    "#{Float.round(mm, 1)} mm (#{effect})"
  end

  defp pressure_note(nil), do: "—"

  defp pressure_note(mb) do
    label =
      cond do
        mb < 1005 -> "low"
        mb < 1015 -> "moderate"
        true -> "high"
      end

    "#{Float.round(mb, 1)} mb (#{label})"
  end

  defp propagation_tier_label(score) do
    cond do
      score >= 80 -> "EXCELLENT"
      score >= 65 -> "GOOD"
      score >= 50 -> "MARGINAL"
      score >= 33 -> "POOR"
      true -> "NEGLIGIBLE"
    end
  end

  defp propagation_tier_class(score) do
    cond do
      score >= 80 -> "badge badge-sm badge-success"
      score >= 65 -> "badge badge-sm badge-info"
      score >= 50 -> "badge badge-sm badge-warning"
      score >= 33 -> "badge badge-sm badge-error"
      true -> "badge badge-sm badge-ghost"
    end
  end
end