feat(contact): loading spinners, callsign-aware summaries, axis callsigns

Three improvements to the contact detail page:

* Track async hydration per source in `hydration_pending` so the
  Terrain / Soundings / Atmospheric Profile sections render a loading
  spinner while their task is in-flight instead of briefly flashing
  "no data available" before the payload arrives.
* Propagation analysis summary now names the origin station by
  callsign ("Path is terrain-obstructed at N mi from W5XD") instead
  of the generic "station 1" placeholder.
* Elevation profile chart labels the 0-mi and max-mi ticks with the
  matching callsign so it's obvious which end of the profile is
  which station.

assets/js/elevation_profile_hook.ts

@@ -168,6 +168,8 @@ export const ElevationProfile: ElevationProfileHook = {
     const n = points.length - 1
     const distances = points.map(p => p.dist_km * KM2MI)
     const showFresnel = data.freq_mhz >= 1000
+    const station1 = this.el.dataset.station1 || ""
+    const station2 = this.el.dataset.station2 || ""
 
     const k = data.k_factor || (4 / 3)
     const R = 6371000
@@ -333,7 +335,18 @@ export const ElevationProfile: ElevationProfileHook = {
             ticks: {
               font: { size: 9 },
               autoSkip: false,
-              callback: (val: number) => distances[val] !== undefined ? Math.round(distances[val]) : ""
+              // Chart.js renders string[] tick labels as stacked lines, so we
+              // tuck the station callsign onto the second line at the 0-mi
+              // and max-mi endpoints — gives each end of the profile a
+              // station identity without needing a separate axis.
+              callback: (val: number) => {
+                const mi = distances[val]
+                if (mi === undefined) return ""
+                const mileage = Math.round(mi)
+                if (val === 0 && station1) return [`${mileage}`, station1]
+                if (val === distances.length - 1 && station2) return [`${mileage}`, station2]
+                return `${mileage}`
+              }
             }
           },
           y: {

lib/microwaveprop_web/live/contact_live/show.ex

@@ -63,6 +63,7 @@ defmodule MicrowavepropWeb.ContactLive.Show do
         sounding_sort_order: "asc",
         queue_counts: fetch_queue_counts(),
         expanded_soundings: MapSet.new(),
+        hydration_pending: MapSet.new(),
         editing: false,
         edit_form: nil,
         pending_edit: load_pending_edit(contact, socket),
@@ -90,6 +91,19 @@ defmodule MicrowavepropWeb.ContactLive.Show do
   # clauses below update the matching slot and re-run the derived analysis.
   defp kickoff_hydration(socket, contact) do
     socket
+    |> assign(
+      :hydration_pending,
+      MapSet.new([
+        :weather,
+        :solar,
+        :hrrr_path,
+        :narr_path,
+        :native_profile,
+        :terrain,
+        :iemre,
+        :radar
+      ])
+    )
     |> start_async(:weather, fn -> load_weather(contact) end)
     |> start_async(:solar, fn -> load_solar(contact) end)
     |> start_async(:hrrr_path, fn -> Weather.hrrr_profiles_for_path(contact) end)
@@ -100,6 +114,16 @@ defmodule MicrowavepropWeb.ContactLive.Show do
     |> start_async(:radar, fn -> load_radar(contact) end)
   end
 
+  defp mark_hydrated(socket, slot) do
+    assign(socket, :hydration_pending, MapSet.delete(socket.assigns.hydration_pending, slot))
+  end
+
+  defp atmospheric_loading?(pending) do
+    MapSet.member?(pending, :hrrr_path) or
+      MapSet.member?(pending, :narr_path) or
+      MapSet.member?(pending, :native_profile)
+  end
+
   defp load_radar(contact) do
     import Ecto.Query
 
@@ -336,6 +360,7 @@ defmodule MicrowavepropWeb.ContactLive.Show do
         surface_observations: weather.surface_observations,
         soundings: weather.soundings
       )
+      |> mark_hydrated(:weather)
       |> refresh_computed()
 
     {:noreply, socket}
@@ -350,7 +375,7 @@ defmodule MicrowavepropWeb.ContactLive.Show do
         solar
       end
 
-    {:noreply, assign(socket, :solar, solar)}
+    {:noreply, socket |> assign(:solar, solar) |> mark_hydrated(:solar)}
   end
 
   def handle_async(:hrrr_path, {:ok, hrrr_path}, socket) do
@@ -363,6 +388,7 @@ defmodule MicrowavepropWeb.ContactLive.Show do
     socket =
       socket
       |> assign(contact: contact, hrrr: hrrr, hrrr_path: hrrr_path)
+      |> mark_hydrated(:hrrr_path)
       |> refresh_computed()
 
     {:noreply, socket}
@@ -375,7 +401,10 @@ defmodule MicrowavepropWeb.ContactLive.Show do
     contact =
       if socket.assigns.can_enqueue, do: maybe_enqueue_narr(narr, contact), else: contact
 
-    {:noreply, assign(socket, contact: contact, narr: narr, narr_path: narr_path)}
+    {:noreply,
+     socket
+     |> assign(contact: contact, narr: narr, narr_path: narr_path)
+     |> mark_hydrated(:narr_path)}
   end
 
   def handle_async(:terrain, {:ok, terrain}, socket) do
@@ -387,27 +416,28 @@ defmodule MicrowavepropWeb.ContactLive.Show do
     socket =
       socket
       |> assign(contact: contact, terrain: terrain)
+      |> mark_hydrated(:terrain)
       |> refresh_computed()
 
     {:noreply, socket}
   end
 
   def handle_async(:iemre, {:ok, iemre}, socket) do
-    {:noreply, assign(socket, :iemre, iemre)}
+    {:noreply, socket |> assign(:iemre, iemre) |> mark_hydrated(:iemre)}
   end
 
   def handle_async(:radar, {:ok, %{row: row, mechanism: mechanism}}, socket) do
-    {:noreply, assign(socket, radar: row, mechanism: mechanism)}
+    {:noreply, socket |> assign(radar: row, mechanism: mechanism) |> mark_hydrated(:radar)}
   end
 
   def handle_async(:native_profile, {:ok, native_profile}, socket) do
-    {:noreply, assign(socket, :native_profile, native_profile)}
+    {:noreply, socket |> assign(:native_profile, native_profile) |> mark_hydrated(:native_profile)}
   end
 
   def handle_async(slot, {:exit, reason}, socket)
-      when slot in [:weather, :solar, :hrrr_path, :narr_path, :native_profile, :terrain, :iemre] do
+      when slot in [:weather, :solar, :hrrr_path, :narr_path, :native_profile, :terrain, :iemre, :radar] do
     Logger.warning("contact hydrate task #{slot} exited: #{inspect(reason)}")
-    {:noreply, socket}
+    {:noreply, mark_hydrated(socket, slot)}
   end
 
   @impl true
@@ -970,6 +1000,8 @@ defmodule MicrowavepropWeb.ContactLive.Show do
             phx-hook="ElevationProfile"
             phx-update="ignore"
             data-profile={Jason.encode!(@elevation_profile)}
+            data-station1={@contact.station1}
+            data-station2={@contact.station2}
             class="w-full h-96 border border-base-300 rounded-lg"
           >
             <canvas></canvas>
@@ -1120,13 +1152,18 @@ defmodule MicrowavepropWeb.ContactLive.Show do
         </div>
       <% else %>
         <div class="text-sm text-base-content/50 italic">
-          <%= if @contact.terrain_status == :queued do %>
-            <span class="flex items-center gap-2">
-              <span class="loading loading-spinner loading-sm"></span>
-              Computing terrain profile {queue_info(@queue_counts, "terrain")}
-            </span>
-          <% else %>
-            No terrain profile available.
+          <%= cond do %>
+            <% MapSet.member?(@hydration_pending, :terrain) -> %>
+              <span class="flex items-center gap-2">
+                <span class="loading loading-spinner loading-sm"></span> Loading terrain profile…
+              </span>
+            <% @contact.terrain_status == :queued -> %>
+              <span class="flex items-center gap-2">
+                <span class="loading loading-spinner loading-sm"></span>
+                Computing terrain profile {queue_info(@queue_counts, "terrain")}
+              </span>
+            <% true -> %>
+              No terrain profile available.
           <% end %>
         </div>
       <% end %>
@@ -1136,13 +1173,18 @@ defmodule MicrowavepropWeb.ContactLive.Show do
       <h2 class="text-base font-semibold mb-2">Soundings</h2>
       <%= if @soundings == [] do %>
         <div class="text-sm text-base-content/50 italic">
-          <%= if @contact.weather_status == :queued do %>
-            <span class="flex items-center gap-2">
-              <span class="loading loading-spinner loading-sm"></span>
-              Fetching sounding data from nearby stations {queue_info(@queue_counts, "weather")}
-            </span>
-          <% else %>
-            No soundings found nearby.
+          <%= cond do %>
+            <% MapSet.member?(@hydration_pending, :weather) -> %>
+              <span class="flex items-center gap-2">
+                <span class="loading loading-spinner loading-sm"></span> Loading soundings…
+              </span>
+            <% @contact.weather_status == :queued -> %>
+              <span class="flex items-center gap-2">
+                <span class="loading loading-spinner loading-sm"></span>
+                Fetching sounding data from nearby stations {queue_info(@queue_counts, "weather")}
+              </span>
+            <% true -> %>
+              No soundings found nearby.
           <% end %>
         </div>
       <% else %>
@@ -1335,18 +1377,22 @@ defmodule MicrowavepropWeb.ContactLive.Show do
         </div>
       <% else %>
         <div class="text-sm text-base-content/50 italic">
-          <%= case @contact.hrrr_status do %>
-            <% :queued -> %>
+          <%= cond do %>
+            <% atmospheric_loading?(@hydration_pending) -> %>
+              <span class="flex items-center gap-2">
+                <span class="loading loading-spinner loading-sm"></span> Loading atmospheric profile…
+              </span>
+            <% @contact.hrrr_status == :queued -> %>
               <span class="flex items-center gap-2">
                 <span class="loading loading-spinner loading-sm"></span>
                 Fetching HRRR atmospheric data {queue_info(@queue_counts, "hrrr")}
               </span>
-            <% :unavailable -> %>
+            <% @contact.hrrr_status == :unavailable -> %>
               <span class="flex items-center gap-2">
                 <span class="loading loading-spinner loading-sm"></span>
                 HRRR unavailable — fetching NARR reanalysis {queue_info(@queue_counts, "narr")}
               </span>
-            <% _ -> %>
+            <% true -> %>
               No atmospheric profile available.
           <% end %>
         </div>
@@ -1934,7 +1980,10 @@ defmodule MicrowavepropWeb.ContactLive.Show do
     hrrr = List.first(hrrr_path)
 
     {factors, factor_rows, composite} = compute_factors(hrrr_path, contact, band_config)
-    summary = build_summary(terrain, elevation_profile, hrrr, soundings, dist_km, band_mhz)
+
+    summary =
+      build_summary(terrain, elevation_profile, hrrr, soundings, dist_km, band_mhz, contact)
+
     details = build_details(hrrr, hrrr_path, soundings, elevation_profile, band_mhz)
 
     %{
@@ -1989,8 +2038,8 @@ defmodule MicrowavepropWeb.ContactLive.Show do
     end
   end
 
-  defp build_summary(terrain, elevation_profile, hrrr, soundings, dist_km, band_mhz) do
-    terrain_status = terrain_summary(terrain, elevation_profile)
+  defp build_summary(terrain, elevation_profile, hrrr, soundings, dist_km, band_mhz, contact) do
+    terrain_status = terrain_summary(terrain, elevation_profile, contact)
     mechanism = propagation_mechanism(terrain, elevation_profile, hrrr, soundings, dist_km)
     band_note = band_summary(band_mhz, hrrr)
 
@@ -1999,28 +2048,31 @@ defmodule MicrowavepropWeb.ContactLive.Show do
     |> Enum.join(" ")
   end
 
-  defp terrain_summary(nil, nil), do: "No terrain data available."
+  defp terrain_summary(nil, nil, _contact), do: "No terrain data available."
 
-  defp terrain_summary(terrain, elevation_profile) do
+  defp terrain_summary(terrain, elevation_profile, contact) do
     verdict = (elevation_profile && elevation_profile.verdict) || (terrain && terrain.verdict)
-    describe_verdict(verdict, elevation_profile)
+    describe_verdict(verdict, elevation_profile, contact)
   end
 
-  defp describe_verdict("CLEAR", _), do: "Line of sight is clear between stations."
-  defp describe_verdict("FRESNEL_MINOR", _), do: "Line of sight is clear but with minor Fresnel zone encroachment."
-  defp describe_verdict("FRESNEL_PARTIAL", _), do: "Line of sight has partial Fresnel zone obstruction."
+  defp describe_verdict("CLEAR", _, _), do: "Line of sight is clear between stations."
+  defp describe_verdict("FRESNEL_MINOR", _, _), do: "Line of sight is clear but with minor Fresnel zone encroachment."
+  defp describe_verdict("FRESNEL_PARTIAL", _, _), do: "Line of sight has partial Fresnel zone obstruction."
 
-  defp describe_verdict("BLOCKED", elevation_profile) do
+  defp describe_verdict("BLOCKED", elevation_profile, contact) do
     obs_dist = elevation_profile && elevation_profile.first_obstruction_km
-    blocked_message(obs_dist)
+    blocked_message(obs_dist, contact)
   end
 
-  defp describe_verdict(_, _), do: nil
+  defp describe_verdict(_, _, _), do: nil
 
-  defp blocked_message(nil), do: "Path is terrain-obstructed."
+  defp blocked_message(nil, _contact), do: "Path is terrain-obstructed."
 
-  defp blocked_message(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."
+  defp blocked_message(obs_dist, contact) do
+    origin = contact && contact.station1
+    origin_label = if origin, do: origin, else: "station 1"
+
+    "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 #{origin_label}."
   end
 
   defp propagation_mechanism(terrain, elevation_profile, hrrr, soundings, dist_km) do