feat(rover): replace max-drive-time slider with max-distance in miles

assets/js/rover_slider_hook.ts

@@ -7,14 +7,11 @@ interface RoverSliderHook extends ViewHook {
   inputHandler: () => void
 }
 
-const AVG_SPEED_KMH = 65.0
+const KM_PER_MI = 1.609344
 
 const formatters: Record<string, (v: number) => string> = {
   forecast: (v) => `+${v}h`,
-  drive: (v) => {
+  distance: (v) => `${v} mi`
-    const hours = Math.round((v / 60) * 10) / 10
-    return `${hours}h`
-  }
 }
 
 export const RoverSlider: Partial<RoverSliderHook> = {
@@ -29,8 +26,8 @@ export const RoverSlider: Partial<RoverSliderHook> = {
       const value = Number((this.el as HTMLInputElement).value)
       if (this.labelEl) this.labelEl.textContent = this.formatter(value)
 
-      if (this.format === "drive") {
+      if (this.format === "distance") {
-        const km = (value * AVG_SPEED_KMH) / 60.0
+        const km = value * KM_PER_MI
         window.dispatchEvent(new CustomEvent("rover:drive-radius", { detail: { km } }))
       }
     }

lib/microwaveprop/rover/compute.ex

@@ -34,7 +34,7 @@ defmodule Microwaveprop.Rover.Compute do
           band_mhz: non_neg_integer(),
           valid_time: DateTime.t(),
           mode: atom(),
-          max_drive_min: integer(),
+          max_distance_km: float(),
           min_elev_gain: integer()
         }
 
@@ -53,12 +53,12 @@ defmodule Microwaveprop.Rover.Compute do
       band_mhz: band_mhz,
       valid_time: valid_time,
       mode: mode,
-      max_drive_min: max_drive_min,
+      max_distance_km: max_distance_km,
       min_elev_gain: min_elev_gain
     } = args
 
     selected_stations = Enum.filter(stations, & &1.selected)
-    radius_km = max_drive_min * @avg_speed_kmh / 60.0
+    radius_km = max_distance_km * 1.0
     bbox = bbox_around(home, radius_km)
 
     raw_cells = scores_at.(band_mhz, valid_time, bbox)

lib/microwaveprop_web/live/rover_live.ex

@@ -31,7 +31,8 @@ defmodule MicrowavepropWeb.RoverLive do
   @default_band 10_000
   @default_mode :ssb
   @default_forecast_hour 0
-  @default_max_drive_min 120
+  @default_max_distance_mi 80
+  @km_per_mi 1.609344
   @avg_speed_kmh 65.0
 
   # NTMS-area anonymous home: EM13 centroid.
@@ -51,8 +52,8 @@ defmodule MicrowavepropWeb.RoverLive do
        band: @default_band,
        mode: @default_mode,
        forecast_hour: @default_forecast_hour,
-       max_drive_min: @default_max_drive_min,
+       max_distance_mi: @default_max_distance_mi,
-       drive_radius_km: drive_radius_km(@default_max_drive_min),
+       drive_radius_km: drive_radius_km(@default_max_distance_mi),
        fixed_stations: fixed_stations,
        persisted?: persisted?,
        home: home,
@@ -163,7 +164,7 @@ defmodule MicrowavepropWeb.RoverLive do
 
   defp home_label(lat, lon), do: Maidenhead.from_latlon(lat, lon, 10)
 
-  defp drive_radius_km(max_drive_min), do: max_drive_min * @avg_speed_kmh / 60.0
+  defp drive_radius_km(max_distance_mi), do: max_distance_mi * @km_per_mi
 
   # ── Events ────────────────────────────────────────────────────────────
 
@@ -178,13 +179,13 @@ defmodule MicrowavepropWeb.RoverLive do
     {:noreply, assign(socket, forecast_hour: hour)}
   end
 
-  def handle_event("set_max_drive_time", %{"value" => v}, socket) do
+  def handle_event("set_max_distance", %{"value" => v}, socket) do
-    minutes = v |> parse_int(@default_max_drive_min) |> clamp(30, 240)
+    miles = v |> parse_int(@default_max_distance_mi) |> clamp(25, 250)
-    radius_km = drive_radius_km(minutes)
+    radius_km = drive_radius_km(miles)
 
     {:noreply,
      socket
-     |> assign(max_drive_min: minutes, drive_radius_km: radius_km)
+     |> assign(max_distance_mi: miles, drive_radius_km: radius_km)
      |> push_event("update_drive_radius", %{km: radius_km})}
   end
 
@@ -666,7 +667,7 @@ defmodule MicrowavepropWeb.RoverLive do
       band_mhz: socket.assigns.band,
       valid_time: socket.assigns.current_valid_time || DateTime.utc_now(),
       mode: socket.assigns.mode,
-      max_drive_min: socket.assigns.max_drive_min,
+      max_distance_km: socket.assigns.drive_radius_km,
       min_elev_gain: 0
     }
   end
@@ -916,26 +917,25 @@ defmodule MicrowavepropWeb.RoverLive do
             </div>
           </.sidebar_section>
 
-          <.sidebar_section title="MAX DRIVE TIME">
+          <.sidebar_section title="MAX DISTANCE">
             <input
               type="range"
-              min="30"
+              min="25"
-              max="240"
+              max="250"
-              step="15"
+              step="25"
-              value={@max_drive_min}
+              value={@max_distance_mi}
-              phx-change="set_max_drive_time"
+              phx-change="set_max_distance"
               phx-debounce="200"
               phx-hook="RoverSlider"
               phx-update="ignore"
-              id="rover-drive-slider"
+              id="rover-distance-slider"
-              data-label-id="rover-drive-label"
+              data-label-id="rover-distance-label"
-              data-format="drive"
+              data-format="distance"
               name="value"
               class="range range-xs range-primary"
             />
             <div class="text-xs opacity-70 mt-1">
-              <span id="rover-drive-label">{Float.round(@max_drive_min / 60, 1)}h</span>
+              <span id="rover-distance-label">{@max_distance_mi} mi</span> from {@home.label}
-              from {@home.label}
             </div>
           </.sidebar_section>
 

test/microwaveprop/rover/compute_test.exs

@@ -28,7 +28,7 @@ defmodule Microwaveprop.Rover.ComputeTest do
       band_mhz: 10_000,
       valid_time: ~U[2026-04-25 12:00:00Z],
       mode: :ssb,
-      max_drive_min: 60,
+      max_distance_km: 65.0,
       min_elev_gain: 0
     }
 
@@ -87,7 +87,7 @@ defmodule Microwaveprop.Rover.ComputeTest do
           band_mhz: 10_000,
           valid_time: ~U[2026-04-25 12:00:00Z],
           mode: :ssb,
-          max_drive_min: 60,
+          max_distance_km: 65.0,
           min_elev_gain: 200
         },
         scores_at: scores_at,

test/microwaveprop_web/live/rover_live_test.exs

@@ -20,7 +20,7 @@ defmodule MicrowavepropWeb.RoverLiveTest do
       assert html =~ "FIXED STATIONS"
       assert html =~ "FORECAST HOUR"
       assert html =~ "BAND"
-      assert html =~ "MAX DRIVE TIME"
+      assert html =~ "MAX DISTANCE"
       refute html =~ ">MODE<"
       refute html =~ "MIN ELEV GAIN"
     end
@@ -63,14 +63,14 @@ defmodule MicrowavepropWeb.RoverLiveTest do
       refute_push_event(view, "rover_results", %{})
     end
 
-    test "set_max_drive_time updates the dashed circle radius", %{conn: conn} do
+    test "set_max_distance updates the dashed circle radius", %{conn: conn} do
       {:ok, view, _html} = live(conn, ~p"/rover")
 
-      render_hook(view, "set_max_drive_time", %{"value" => "120"})
+      render_hook(view, "set_max_distance", %{"value" => "100"})
 
-      # 120 min @ 65 km/h = 130 km
+      # 100 mi = 160.93 km
       assert_push_event(view, "update_drive_radius", %{km: km})
-      assert_in_delta km, 130.0, 0.1
+      assert_in_delta km, 160.93, 0.1
     end
 
     test "calculate triggers a rover_results push_event with cells + drive_radius_km", %{conn: conn} do