add favicon and site icon generation from uploaded images

Upload a source image (PNG, JPEG, or SVG) and get a complete favicon
setup: PNG variants at 32, 180, 192, 512px served from DB via
FaviconController with ETag caching, SVG favicon for vector sources,
dynamic site.webmanifest, and theme-color meta tag. Theme editor gains
a site icon section with "use logo as icon" toggle, dedicated icon
upload, short name, and background colour picker.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

lib/berrypod_web/live/admin/theme/index.ex

@@ -4,6 +4,7 @@ defmodule BerrypodWeb.Admin.Theme.Index do
   alias Berrypod.Settings
   alias Berrypod.Media
   alias Berrypod.Theme.{CSSGenerator, Presets, PreviewData}
+  alias Berrypod.Workers.FaviconGeneratorWorker
 
   @impl true
   def mount(_params, _session, socket) do
@@ -20,6 +21,7 @@ defmodule BerrypodWeb.Admin.Theme.Index do
 
     logo_image = Media.get_logo()
     header_image = Media.get_header()
+    icon_image = Media.get_icon()
 
     socket =
       socket
@@ -31,6 +33,7 @@ defmodule BerrypodWeb.Admin.Theme.Index do
       |> assign(:preview_data, preview_data)
       |> assign(:logo_image, logo_image)
       |> assign(:header_image, header_image)
+      |> assign(:icon_image, icon_image)
       |> assign(:customise_open, false)
       |> assign(:sidebar_collapsed, false)
       |> assign(:cart_drawer_open, false)
@@ -48,6 +51,13 @@ defmodule BerrypodWeb.Admin.Theme.Index do
         auto_upload: true,
         progress: &handle_progress/3
       )
+      |> allow_upload(:icon_upload,
+        accept: ~w(.png .jpg .jpeg .webp .svg),
+        max_entries: 1,
+        max_file_size: 5_000_000,
+        auto_upload: true,
+        progress: &handle_progress/3
+      )
 
     {:ok, socket}
   end
@@ -66,6 +76,11 @@ defmodule BerrypodWeb.Admin.Theme.Index do
       end)
       |> case do
         [image | _] ->
+          # Trigger favicon generation if using logo as icon
+          if socket.assigns.theme_settings.use_logo_as_icon do
+            enqueue_favicon_generation(image.id)
+          end
+
           {:noreply, assign(socket, :logo_image, image)}
 
         _ ->
@@ -100,6 +115,31 @@ defmodule BerrypodWeb.Admin.Theme.Index do
     end
   end
 
+  defp handle_progress(:icon_upload, entry, socket) do
+    if entry.done? do
+      consume_uploaded_entries(socket, :icon_upload, fn %{path: path}, entry ->
+        case Media.upload_from_entry(path, entry, "icon") do
+          {:ok, image} ->
+            Settings.update_theme_settings(%{icon_image_id: image.id})
+            {:ok, image}
+
+          {:error, _} = error ->
+            error
+        end
+      end)
+      |> case do
+        [image | _] ->
+          enqueue_favicon_generation(image.id)
+          {:noreply, assign(socket, :icon_image, image)}
+
+        _ ->
+          {:noreply, socket}
+      end
+    else
+      {:noreply, socket}
+    end
+  end
+
   @impl true
   def handle_event("apply_preset", %{"preset" => preset_name}, socket) do
     preset_atom = String.to_existing_atom(preset_name)
@@ -221,6 +261,11 @@ defmodule BerrypodWeb.Admin.Theme.Index do
         generated_css = CSSGenerator.generate(theme_settings)
         active_preset = Presets.detect_preset(theme_settings)
 
+        # Trigger favicon regeneration when the icon source changes
+        if field_atom == :use_logo_as_icon do
+          maybe_enqueue_favicon_from_settings(theme_settings, socket.assigns)
+        end
+
         socket =
           socket
           |> assign(:theme_settings, theme_settings)
@@ -272,6 +317,22 @@ defmodule BerrypodWeb.Admin.Theme.Index do
     {:noreply, socket}
   end
 
+  @impl true
+  def handle_event("remove_icon", _params, socket) do
+    if icon = socket.assigns.icon_image do
+      Media.delete_image(icon)
+    end
+
+    Settings.update_theme_settings(%{icon_image_id: nil})
+
+    socket =
+      socket
+      |> assign(:icon_image, nil)
+      |> put_flash(:info, "Icon removed")
+
+    {:noreply, socket}
+  end
+
   @impl true
   def handle_event("cancel_upload", %{"ref" => ref, "upload" => upload_name}, socket) do
     upload_atom = String.to_existing_atom(upload_name)
@@ -308,6 +369,29 @@ defmodule BerrypodWeb.Admin.Theme.Index do
   def error_to_string(:not_accepted), do: "File type not accepted"
   def error_to_string(err), do: inspect(err)
 
+  defp enqueue_favicon_generation(source_image_id) do
+    %{source_image_id: source_image_id}
+    |> FaviconGeneratorWorker.new()
+    |> Oban.insert()
+  end
+
+  defp maybe_enqueue_favicon_from_settings(theme_settings, assigns) do
+    source_id =
+      if theme_settings.use_logo_as_icon do
+        case assigns.logo_image do
+          %{id: id} -> id
+          _ -> nil
+        end
+      else
+        case assigns.icon_image do
+          %{id: id} -> id
+          _ -> nil
+        end
+      end
+
+    if source_id, do: enqueue_favicon_generation(source_id)
+  end
+
   defp preview_assigns(assigns) do
     assign(assigns, %{
       mode: :preview,

lib/berrypod_web/live/admin/theme/index.html.heex

@@ -266,6 +266,143 @@
           <% end %>
         </div>
         
+<!-- Site Icon / Favicon -->
+        <div class="bg-base-200 rounded-xl p-4 mb-6">
+          <label class="block text-xs font-semibold uppercase tracking-wider text-base-content/60 mb-3">
+            Site icon
+          </label>
+          <p class="text-xs text-base-content/50 mb-4">
+            Your icon appears in browser tabs and on home screens.
+          </p>
+          
+<!-- Use logo as icon toggle -->
+          <label class="flex items-center gap-2 cursor-pointer mb-4">
+            <input
+              type="checkbox"
+              checked={@theme_settings.use_logo_as_icon}
+              phx-click="toggle_setting"
+              phx-value-field="use_logo_as_icon"
+              class="admin-toggle admin-toggle-sm"
+            />
+            <span class="text-sm text-base-content/70">Use logo as favicon</span>
+          </label>
+          
+<!-- Icon upload (only when not using logo) -->
+          <%= if !@theme_settings.use_logo_as_icon do %>
+            <div class="pt-3 border-t border-base-300">
+              <span class="block text-xs font-medium text-base-content/70 mb-2">
+                Upload icon (PNG or SVG, 512×512+)
+              </span>
+              <div class="flex items-center gap-3">
+                <form phx-change="noop" phx-submit="noop" class="flex-1">
+                  <label class="flex-1 bg-base-100 border border-dashed border-base-300 rounded-lg p-3 text-sm text-base-content/60 text-center cursor-pointer hover:border-base-content/40 hover:text-base-content/80 transition-all">
+                    <span>Choose file...</span>
+                    <.live_file_input upload={@uploads.icon_upload} class="hidden" />
+                  </label>
+                </form>
+                <%= if @icon_image do %>
+                  <div class="relative w-10 h-10 bg-base-100 border border-base-300 rounded-lg flex items-center justify-center overflow-hidden">
+                    <%= if @icon_image.is_svg do %>
+                      <img
+                        src={"/images/#{@icon_image.id}/recolored/000000"}
+                        alt="Current icon"
+                        class="max-w-full max-h-full object-contain"
+                      />
+                    <% else %>
+                      <img
+                        src={"/image_cache/#{@icon_image.id}.webp"}
+                        alt="Current icon"
+                        class="max-w-full max-h-full object-contain"
+                      />
+                    <% end %>
+                    <button
+                      type="button"
+                      phx-click="remove_icon"
+                      class="absolute -top-1.5 -right-1.5 w-[18px] h-[18px] bg-base-content text-base-100 rounded-full text-xs flex items-center justify-center leading-none"
+                      title="Remove icon"
+                    >
+                      ×
+                    </button>
+                  </div>
+                <% end %>
+              </div>
+
+              <%= for entry <- @uploads.icon_upload.entries do %>
+                <div class="flex items-center gap-2 mt-2">
+                  <div class="flex-1 h-1.5 bg-base-300 rounded-full overflow-hidden">
+                    <div
+                      class="h-full bg-primary transition-all"
+                      style={"width: #{entry.progress}%"}
+                    >
+                    </div>
+                  </div>
+                  <span class="text-xs text-base-content/60">{entry.progress}%</span>
+                  <button
+                    type="button"
+                    phx-click="cancel_upload"
+                    phx-value-ref={entry.ref}
+                    phx-value-upload="icon_upload"
+                    class="text-base-content/40 hover:text-base-content/70"
+                  >
+                    ×
+                  </button>
+                </div>
+                <%= for err <- upload_errors(@uploads.icon_upload, entry) do %>
+                  <p class="text-error text-xs mt-1">{error_to_string(err)}</p>
+                <% end %>
+              <% end %>
+
+              <%= for err <- upload_errors(@uploads.icon_upload) do %>
+                <p class="text-error text-xs mt-1">{error_to_string(err)}</p>
+              <% end %>
+            </div>
+          <% end %>
+          
+<!-- Short name -->
+          <div class="mt-4 pt-3 border-t border-base-300">
+            <form phx-change="update_setting" phx-value-field="favicon_short_name">
+              <div class="flex justify-between items-center mb-1">
+                <span class="text-xs font-medium text-base-content/70">Short name</span>
+                <span class="text-xs text-base-content/50">Home screen label</span>
+              </div>
+              <input
+                type="text"
+                name="favicon_short_name"
+                value={@theme_settings.favicon_short_name}
+                placeholder={String.slice(@theme_settings.site_name, 0, 12)}
+                maxlength="12"
+                class="w-full px-3 py-2 border border-base-300 rounded-lg text-sm bg-base-100 text-base-content focus:outline-none focus:border-primary focus:ring-1 focus:ring-primary/20 transition-all"
+              />
+            </form>
+          </div>
+          
+<!-- Icon background colour -->
+          <div class="mt-3">
+            <form
+              id="icon-bg-color-form"
+              phx-change="update_color"
+              phx-value-field="icon_background_color"
+              phx-hook="ColorSync"
+              class="flex items-center gap-3"
+            >
+              <input
+                type="color"
+                name="value"
+                value={@theme_settings.icon_background_color}
+                class="w-9 h-9 rounded-lg cursor-pointer border-0 p-0"
+              />
+              <div>
+                <span class="text-xs font-medium text-base-content/70 block">
+                  Icon background
+                </span>
+                <span class="font-mono text-xs text-base-content/50">
+                  {@theme_settings.icon_background_color}
+                </span>
+              </div>
+            </form>
+          </div>
+        </div>
+        
 <!-- Header Background Toggle -->
         <div class="mb-6">
           <label class="flex items-center gap-2 cursor-pointer">