consolidate image serving and clean up pipeline

Move all image URL logic into ProductImage.url/2 and thumbnail_url/1,
remove dead on-demand generation code from Optimizer, strip controller
routes down to SVG recolor only, fix mockup startup check to verify all
variant formats, and isolate test image cache directory.

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

lib/simpleshop_theme_web/controllers/image_controller.ex

@@ -4,168 +4,6 @@ defmodule SimpleshopThemeWeb.ImageController do
   alias SimpleshopTheme.Media
   alias SimpleshopTheme.Media.SVGRecolorer
 
-  @doc """
-  Serves an image from the database by ID.
-
-  Images are served with aggressive caching headers since they are
-  immutable once uploaded.
-  """
-  def show(conn, %{"id" => id}) do
-    etag = ~s("#{id}")
-
-    if etag_match?(conn, etag) do
-      send_not_modified(conn, etag)
-    else
-      case Media.get_image(id) do
-        nil ->
-          send_resp(conn, 404, "Image not found")
-
-        image ->
-          conn
-          |> put_resp_content_type(image.content_type)
-          |> put_resp_header("cache-control", "public, max-age=31536000, immutable")
-          |> put_resp_header("etag", etag)
-          |> send_resp(200, image.data)
-      end
-    end
-  end
-
-  @doc """
-  Serves a thumbnail of an image from the disk cache.
-
-  Thumbnails are generated by the background image optimization pipeline.
-  If the thumbnail doesn't exist on disk yet (still processing), generates
-  it on-demand and saves it for future requests.
-  """
-  def thumbnail(conn, %{"id" => id}) do
-    etag = ~s("#{id}-thumb")
-
-    if etag_match?(conn, etag) do
-      send_not_modified(conn, etag)
-    else
-      thumb_path = Media.get_thumbnail_path(id)
-
-      if File.exists?(thumb_path) do
-        conn
-        |> put_resp_content_type("image/jpeg")
-        |> put_resp_header("cache-control", "public, max-age=31536000, immutable")
-        |> put_resp_header("etag", etag)
-        |> send_file(200, thumb_path)
-      else
-        case Media.get_image(id) do
-          nil ->
-            send_resp(conn, 404, "Image not found")
-
-          %{data: data} when is_binary(data) ->
-            case generate_thumbnail_on_demand(data, thumb_path) do
-              {:ok, binary} ->
-                conn
-                |> put_resp_content_type("image/jpeg")
-                |> put_resp_header("cache-control", "public, max-age=31536000, immutable")
-                |> put_resp_header("etag", etag)
-                |> send_resp(200, binary)
-
-              {:error, _} ->
-                conn
-                |> put_resp_content_type("image/webp")
-                |> put_resp_header("cache-control", "public, max-age=31536000, immutable")
-                |> send_resp(200, data)
-            end
-
-          %{data: nil} ->
-            send_resp(conn, 404, "Image data not available")
-        end
-      end
-    end
-  end
-
-  defp generate_thumbnail_on_demand(image_data, thumb_path) do
-    with {:ok, image} <- Image.from_binary(image_data),
-         {:ok, thumb} <- Image.thumbnail(image, 200),
-         {:ok, binary} <- Image.write(thumb, :memory, suffix: ".jpg", quality: 80) do
-      # Ensure cache directory exists and save for future requests
-      File.mkdir_p!(Path.dirname(thumb_path))
-      File.write!(thumb_path, binary)
-      {:ok, binary}
-    end
-  rescue
-    _ -> {:error, :thumbnail_generation_failed}
-  end
-
-  @supported_formats %{"avif" => :avif, "webp" => :webp, "jpg" => :jpg}
-
-  @doc """
-  Serves an image variant at the specified width and format.
-
-  Supports AVIF, WebP, and JPEG formats. If the variant doesn't exist on disk
-  (e.g., cache was deleted), it will be generated on-demand and cached.
-
-  JPEG variants are never pre-generated (to save disk space), so they are
-  always generated on first request.
-
-  ## URL format
-
-      /images/:id/variant/:width.:format
-
-  Examples:
-  - `/images/abc123/variant/800.avif`
-  - `/images/abc123/variant/400.webp`
-  - `/images/abc123/variant/1200.jpg`
-  """
-  def variant(conn, %{"id" => id, "width" => width_with_ext}) do
-    alias SimpleshopTheme.Images.Optimizer
-
-    with {width, format} <- parse_width_and_format(width_with_ext),
-         true <- width in Optimizer.all_widths() do
-      etag = ~s("#{id}-#{width}.#{format}")
-
-      if etag_match?(conn, etag) do
-        send_not_modified(conn, etag)
-      else
-        case Media.get_image(id) do
-          %{data: data} when is_binary(data) ->
-            case Optimizer.generate_variant_on_demand(data, id, width, format) do
-              {:ok, path} ->
-                conn
-                |> put_resp_content_type(format_content_type(format))
-                |> put_resp_header("cache-control", "public, max-age=31536000, immutable")
-                |> put_resp_header("etag", etag)
-                |> send_file(200, path)
-
-              {:error, _reason} ->
-                send_resp(conn, 500, "Failed to generate variant")
-            end
-
-          nil ->
-            send_resp(conn, 404, "Image not found")
-
-          %{data: nil} ->
-            send_resp(conn, 404, "Image data not available")
-        end
-      end
-    else
-      :error -> send_resp(conn, 400, "Invalid width or format")
-      false -> send_resp(conn, 400, "Width not supported")
-    end
-  end
-
-  defp parse_width_and_format(width_with_ext) do
-    case String.split(width_with_ext, ".") do
-      [width_str, ext] when is_map_key(@supported_formats, ext) ->
-        case Integer.parse(width_str) do
-          {width, ""} -> {width, @supported_formats[ext]}
-          _ -> :error
-        end
-
-      _ ->
-        :error
-    end
-  end
-
-  defp format_content_type(:avif), do: "image/avif"
-  defp format_content_type(:webp), do: "image/webp"
-  defp format_content_type(:jpg), do: "image/jpeg"
-
   @doc """
   Serves an SVG image recolored with the specified color.
 
@@ -208,18 +46,4 @@ defmodule SimpleshopThemeWeb.ImageController do
       "#" <> color
     end
   end
-
-  defp etag_match?(conn, etag) do
-    case Plug.Conn.get_req_header(conn, "if-none-match") do
-      [^etag] -> true
-      _ -> false
-    end
-  end
-
-  defp send_not_modified(conn, etag) do
-    conn
-    |> put_resp_header("cache-control", "public, max-age=31536000, immutable")
-    |> put_resp_header("etag", etag)
-    |> send_resp(304, "")
-  end
 end