From a30d6b821923ac16881853183ad7428a70d95f5b Mon Sep 17 00:00:00 2001
From: Graham McIntire <graham@mcintire.me>
Date: Sun, 25 Jan 2026 13:59:09 -0600
Subject: [PATCH] unit fixes

---
 lib/towerops_web/live/graph_live/show.ex      | 67 +++++++++++++++++++
 .../live/graph_live/show.html.heex            | 16 +++++
 2 files changed, 83 insertions(+)

diff --git a/lib/towerops_web/live/graph_live/show.ex b/lib/towerops_web/live/graph_live/show.ex
index 2aa49f42..3e7a7b57 100644
--- a/lib/towerops_web/live/graph_live/show.ex
+++ b/lib/towerops_web/live/graph_live/show.ex
@@ -84,6 +84,9 @@ defmodule ToweropsWeb.GraphLive.Show do
     chart_title = if title_suffix, do: "#{title} - #{title_suffix}", else: title
     show_zero_line = sensor_type == "traffic"
 
+    # Calculate max/min values from chart data
+    {max_value, min_value} = calculate_chart_stats(chart_data)
+
     socket
     |> assign(:device, device)
     |> assign(:page_title, "#{device.name} - #{chart_title}")
@@ -92,6 +95,8 @@ defmodule ToweropsWeb.GraphLive.Show do
     |> assign(:unit, unit)
     |> assign(:auto_scale, auto_scale)
     |> assign(:show_zero_line, show_zero_line)
+    |> assign(:max_value, max_value)
+    |> assign(:min_value, min_value)
   end
 
   defp load_chart_data_for_type(%{sensor_type: "latency", device_id: device_id}, range) do
@@ -320,6 +325,39 @@ defmodule ToweropsWeb.GraphLive.Show do
     }
   end
 
+  # Calculate max and min values from chart data
+  defp calculate_chart_stats(nil), do: {nil, nil}
+
+  defp calculate_chart_stats(chart_data) when is_binary(chart_data) do
+    case Jason.decode(chart_data) do
+      {:ok, %{"datasets" => datasets}} ->
+        extract_min_max_from_datasets(datasets)
+
+      _ ->
+        {nil, nil}
+    end
+  end
+
+  defp calculate_chart_stats(_), do: {nil, nil}
+
+  defp extract_min_max_from_datasets(datasets) do
+    values = Enum.flat_map(datasets, &extract_values_from_dataset/1)
+
+    case values do
+      [] -> {nil, nil}
+      _ -> {Enum.max(values), Enum.min(values)}
+    end
+  end
+
+  defp extract_values_from_dataset(%{"data" => data}) when is_list(data) do
+    Enum.flat_map(data, &extract_y_value/1)
+  end
+
+  defp extract_values_from_dataset(_), do: []
+
+  defp extract_y_value(%{"y" => y}) when is_number(y), do: [y]
+  defp extract_y_value(_), do: []
+
   defp build_traffic_chart_json(device, range) do
     if Enum.empty?(device.interfaces), do: nil, else: build_traffic_datasets(device, range)
   end
@@ -420,4 +458,33 @@ defmodule ToweropsWeb.GraphLive.Show do
       }
     end)
   end
+
+  # Format value with unit for display
+  defp format_value(value, "bps") do
+    abs_value = abs(value)
+
+    cond do
+      abs_value >= 1_000_000_000 ->
+        "#{Float.round(abs_value / 1_000_000_000, 2)} Gbps"
+
+      abs_value >= 1_000_000 ->
+        "#{Float.round(abs_value / 1_000_000, 2)} Mbps"
+
+      abs_value >= 1_000 ->
+        "#{Float.round(abs_value / 1_000, 2)} Kbps"
+
+      true ->
+        "#{Float.round(abs_value, 2)} bps"
+    end
+  end
+
+  # For counts (empty unit), format as integer
+  defp format_value(value, "") do
+    "#{round(value)}"
+  end
+
+  # For other units, format with one decimal place
+  defp format_value(value, unit) do
+    "#{Float.round(value, 1)}#{unit}"
+  end
 end
diff --git a/lib/towerops_web/live/graph_live/show.html.heex b/lib/towerops_web/live/graph_live/show.html.heex
index cf65a8d4..65b9245f 100644
--- a/lib/towerops_web/live/graph_live/show.html.heex
+++ b/lib/towerops_web/live/graph_live/show.html.heex
@@ -59,6 +59,22 @@
           >
             <canvas></canvas>
           </div>
+          <%= if @max_value && @min_value do %>
+            <div class="mt-4 pt-4 border-t border-gray-200 dark:border-white/10 flex justify-center gap-8 text-sm">
+              <div class="flex items-center gap-2">
+                <span class="font-medium text-gray-700 dark:text-gray-300">Max:</span>
+                <span class="text-gray-900 dark:text-white font-semibold">
+                  {format_value(@max_value, @unit)}
+                </span>
+              </div>
+              <div class="flex items-center gap-2">
+                <span class="font-medium text-gray-700 dark:text-gray-300">Min:</span>
+                <span class="text-gray-900 dark:text-white font-semibold">
+                  {format_value(@min_value, @unit)}
+                </span>
+              </div>
+            </div>
+          <% end %>
         </div>
       </div>
     <% else %>