feat: pipeline to create a full mac app

README.md

@@ -162,3 +162,56 @@ Notes for developers:
 - [DOCUMENTATION.md](/Users/gb/Projects/bDS2/DOCUMENTATION.md) is for end users, not implementation details.
 - [API.md](/Users/gb/Projects/bDS2/API.md) is generated from the live scripting capability map and should stay in sync with runtime changes.
 - When changing persistence or localization behavior, check both the database side and the filesystem/render side before assuming the change is complete.
+
+## Packaging The macOS App
+
+`mix bds.bundle.macos` produces a self-contained, ad-hoc-signed `BDS2.app`. It
+bundles the `:bds` release (ERTS included) plus the wxWidgets dylibs relocated
+via `@loader_path`, so it runs on a clean Mac with nothing installed. The bundle
+registers the `bds2://` URL scheme (for blogmark deep links) and ships the red-pen
+`AppIcon`. Output: `dist/macos/BDS2.app`. (arm64 / Apple Silicon only.)
+
+### 1. Build the release, then the bundle
+
+```bash
+MIX_ENV=prod mix release bds --overwrite
+mix bds.bundle.macos --app-release _build/prod/rel/bds
+```
+
+The icon `.icns` is generated on first run from
+[priv/desktop/macos/icon-source.svg](/Users/gb/Projects/bDS2/priv/desktop/macos/icon-source.svg)
+and committed under `priv/desktop/macos/`. Pass `--regen-icon` to rebuild it.
+
+### 2. Register the `bds2://` scheme (optional)
+
+`--register` tells LaunchServices about the scheme without moving the app to
+`/Applications` — useful for testing blogmark deep links locally:
+
+```bash
+mix bds.bundle.macos --app-release _build/prod/rel/bds --register
+```
+
+### Run / smoke-test
+
+```bash
+open dist/macos/BDS2.app
+open "bds2://new-post?title=Hello&url=https://example.com"   # opens a draft
+```
+
+### Useful flags
+
+- `--app-release PATH` — release dir to wrap (default `_build/<env>/rel/bds`).
+- `--output DIR` — output directory (default `dist/macos`).
+- `--version V` — version string for `Info.plist` (default from `mix.exs`).
+- `--regen-icon` — regenerate `AppIcon.icns` from the source SVG.
+- `--register` — register the `bds2://` scheme via LaunchServices.
+- `--no-codesign` — skip the ad-hoc codesign step.
+
+### Verifying the bundle
+
+```bash
+plutil -lint dist/macos/BDS2.app/Contents/Info.plist
+codesign --verify --deep --strict dist/macos/BDS2.app
+# no /opt/homebrew or /usr/local references should appear:
+otool -L dist/macos/BDS2.app/Contents/Resources/rel/lib/wx-*/priv/wxe_driver.so
+```

lib/bds/desktop/deep_link.ex

@@ -3,12 +3,13 @@ defmodule BDS.Desktop.DeepLink do
   Receives OS URL-scheme events for the `bds2://` scheme and routes them to the
   shell (spec: script.allium `BlogmarkReceived`).
 
-  On macOS the app bundle registers `bds2://` as a custom URL scheme (see the
-  `CFBundleURLTypes` entry in the packaged `Info.plist`). When the browser
-  bookmarklet navigates to `bds2://new-post?title=&url=`, the OS launches/raises
-  the app and `Desktop.Env` delivers an `{:open_url, [url]}` event. This
-  GenServer subscribes to those events and forwards recognised `bds2://` links to
-  the live shell over PubSub, where `BDS.Blogmark` turns them into draft posts.
+  On macOS the `BDS2.app` bundle registers `bds2://` as a custom URL scheme via
+  the `CFBundleURLTypes` entry in its `Info.plist` (built by `BDS.MacBundle` /
+  `mix bds.bundle.macos`). When the browser bookmarklet navigates to
+  `bds2://new-post?title=&url=`, the OS launches/raises the app and `Desktop.Env`
+  delivers an `{:open_url, [url]}` event. This GenServer subscribes to those
+  events and forwards recognised `bds2://` links to the live shell over PubSub,
+  where `BDS.Blogmark` turns them into draft posts.
 
   The `bds2://` scheme is distinct from the legacy app's `bds://` so the two
   installs do not contend for the same registration.

lib/bds/mac_bundle.ex

@@ -0,0 +1,179 @@
+defmodule BDS.MacBundle do
+  @moduledoc """
+  Assembles a self-contained, ad-hoc-signed macOS `.app` bundle for bDS2.
+
+  The bundle wraps the `:bds` Elixir release (which already embeds ERTS), a
+  red-pen `AppIcon.icns` (`BDS.MacBundle.Icon`), and the wxWidgets dylibs the
+  `:wx` NIF needs, relocated to run on a clean Mac (`BDS.MacBundle.Dylibs`). Its
+  `Info.plist` registers the `bds2://` URL scheme so the OS forwards blogmark
+  deep links to the running app (`Desktop.Env` → `BDS.Desktop.DeepLink`).
+
+  Layout:
+
+      BDS2.app/Contents/
+        Info.plist  PkgInfo
+        MacOS/bds2                 # launcher script (execs the release)
+        Resources/AppIcon.icns
+        Resources/rel/             # the mix release (ERTS bundled)
+        Frameworks/                # relocated wx + transitive dylibs
+  """
+
+  alias BDS.MacBundle.Dylibs
+
+  @identifier "de.rfc1437.bds2"
+  @display_name "Blogging Desktop Server"
+  @executable "bds2"
+  @icon_name "AppIcon"
+  @scheme "bds2"
+  @min_system "13.0"
+  @release_name "bds"
+  @app_dir_name "BDS2.app"
+
+  @doc "Render the `Info.plist` XML for the bundle."
+  @spec info_plist(keyword()) :: String.t()
+  def info_plist(opts \\ []) do
+    assigns = [
+      identifier: Keyword.get(opts, :identifier, @identifier),
+      name: Keyword.get(opts, :name, @display_name),
+      executable: Keyword.get(opts, :executable, @executable),
+      icon: Keyword.get(opts, :icon, @icon_name),
+      scheme: Keyword.get(opts, :scheme, @scheme),
+      min_system: Keyword.get(opts, :min_system, @min_system),
+      version: Keyword.get(opts, :version, "0.0.0")
+    ]
+
+    EEx.eval_file(template_path("Info.plist.eex"), assigns)
+  end
+
+  @doc "Render the `Contents/MacOS` launcher shell script."
+  @spec launcher(keyword()) :: String.t()
+  def launcher(opts \\ []) do
+    assigns = [
+      identifier: Keyword.get(opts, :identifier, @identifier),
+      name: Keyword.get(opts, :name, @display_name),
+      release_name: Keyword.get(opts, :release_name, @release_name)
+    ]
+
+    EEx.eval_file(template_path("launcher.sh.eex"), assigns)
+  end
+
+  @doc """
+  Assemble the `.app` from a built release directory.
+
+  Options:
+    * `:release_dir`  — path to the `:bds` release (required)
+    * `:output_dir`   — where to place `BDS2.app` (required)
+    * `:icns_path`    — path to `AppIcon.icns` (required)
+    * `:version`      — version string for `Info.plist` (default "0.0.0")
+    * `:skip_dylibs`  — skip wx dylib relocation (tests; default false)
+    * `:skip_codesign`— skip ad-hoc codesign (tests; default false)
+  """
+  @spec assemble(keyword()) :: {:ok, String.t()} | {:error, term()}
+  def assemble(opts) do
+    release_dir = Keyword.fetch!(opts, :release_dir)
+    output_dir = Keyword.fetch!(opts, :output_dir)
+    icns_path = Keyword.fetch!(opts, :icns_path)
+    version = Keyword.get(opts, :version, "0.0.0")
+
+    app = Path.join(output_dir, @app_dir_name)
+    contents = Path.join(app, "Contents")
+    macos = Path.join(contents, "MacOS")
+    resources = Path.join(contents, "Resources")
+    frameworks = Path.join(contents, "Frameworks")
+    rel = Path.join(resources, "rel")
+
+    File.rm_rf!(app)
+    Enum.each([macos, resources, frameworks], &File.mkdir_p!/1)
+
+    with {:ok, _} <- File.cp_r(release_dir, rel),
+         :ok <- File.cp(icns_path, Path.join(resources, "#{@icon_name}.icns")),
+         :ok <- File.write(Path.join(contents, "Info.plist"), info_plist(version: version)),
+         :ok <- File.write(Path.join(contents, "PkgInfo"), "APPL????"),
+         :ok <- write_launcher(Path.join(macos, @executable)),
+         :ok <- maybe_relocate_dylibs(rel, frameworks, opts),
+         :ok <- maybe_codesign(app, opts) do
+      {:ok, app}
+    end
+  end
+
+  @doc "Locate the wxWidgets NIF (`wxe_driver.so`) inside a release tree."
+  @spec wx_nif_path(String.t()) :: String.t() | nil
+  def wx_nif_path(release_dir) do
+    release_dir
+    |> Path.join("lib/wx-*/priv/wxe_driver.so")
+    |> Path.wildcard()
+    |> List.first()
+  end
+
+  defp write_launcher(path) do
+    with :ok <- File.write(path, launcher()) do
+      File.chmod(path, 0o755)
+    end
+  end
+
+  defp maybe_relocate_dylibs(_rel, _frameworks, opts) do
+    if Keyword.get(opts, :skip_dylibs, false) do
+      :ok
+    else
+      relocate_dylibs(opts[:release_dir], opts)
+    end
+  end
+
+  defp relocate_dylibs(release_dir, opts) do
+    app = Path.join(opts[:output_dir], @app_dir_name)
+    frameworks = Path.join(app, "Contents/Frameworks")
+
+    case wx_nif_path(Path.join(app, "Contents/Resources/rel")) do
+      nil ->
+        {:error, {:wx_nif_not_found, release_dir}}
+
+      nif ->
+        prefix = "@loader_path/" <> relative_up(Path.dirname(nif), frameworks)
+
+        case Dylibs.bundle(nif, frameworks, prefix) do
+          {:ok, _copied} -> :ok
+          error -> error
+        end
+    end
+  end
+
+  @doc """
+  Compute a `../`-style relative path from `from_dir` to `to` (both absolute),
+  e.g. the path from the wx NIF's directory up to `Contents/Frameworks`.
+  """
+  @spec relative_up(String.t(), String.t()) :: String.t()
+  def relative_up(from_dir, to) do
+    from = Path.split(Path.expand(from_dir))
+    target = Path.split(Path.expand(to))
+    {rest_from, rest_to} = drop_common(from, target)
+    (List.duplicate("..", length(rest_from)) ++ rest_to) |> Path.join()
+  end
+
+  defp drop_common([h | from], [h | to]), do: drop_common(from, to)
+  defp drop_common(from, to), do: {from, to}
+
+  defp maybe_codesign(app, opts) do
+    if Keyword.get(opts, :skip_codesign, false), do: :ok, else: codesign(app)
+  end
+
+  @doc """
+  Ad-hoc codesign the whole bundle recursively. `--deep` signs every nested
+  Mach-O (the relocated dylibs and the release's `beam.smp`/`erlexec`/escripts),
+  then we verify with `--deep --strict`.
+  """
+  @spec codesign(String.t()) :: :ok | {:error, term()}
+  def codesign(app) do
+    with :ok <- run("codesign", ["--force", "--deep", "--sign", "-", "--timestamp=none", app]) do
+      run("codesign", ["--verify", "--deep", "--strict", app])
+    end
+  end
+
+  defp run(cmd, args) do
+    case System.cmd(cmd, args, stderr_to_stdout: true) do
+      {_out, 0} -> :ok
+      {out, status} -> {:error, {:command_failed, cmd, status, out}}
+    end
+  end
+
+  defp template_path(name), do: Path.join(:code.priv_dir(:bds), "desktop/macos/#{name}")
+end

lib/bds/mac_bundle/dylibs.ex

@@ -0,0 +1,158 @@
+defmodule BDS.MacBundle.Dylibs do
+  @moduledoc """
+  Makes the bundled Elixir release self-contained on macOS by relocating the
+  non-system dynamic libraries the wxWidgets NIF (`wxe_driver.so`) links against.
+
+  Erlang's `:wx` driver is built against the wxWidgets dylibs of whatever host
+  produced the OTP install (typically Homebrew under `/opt/homebrew`), so a
+  release copied to a clean Mac would fail to load `:wx`. We copy every external
+  dylib (and its transitive deps) into `Contents/Frameworks/`, then rewrite the
+  install names with `install_name_tool` to `@executable_path/../Frameworks/...`.
+
+  The `otool`/`install_name_tool` parsing and argument building are pure so they
+  can be unit-tested; `bundle/2` performs the actual filesystem + tool work.
+  """
+
+  # Homebrew prefixes whose libraries must be copied into the bundle. Anything
+  # under /usr/lib or /System is part of macOS and stays referenced in place;
+  # @rpath/@executable_path/@loader_path are already relocatable.
+  @external_prefixes ["/opt/homebrew", "/usr/local"]
+
+  @doc "Parse `otool -L` output into the ordered list of dependency paths."
+  @spec parse_otool(String.t()) :: [String.t()]
+  def parse_otool(output) when is_binary(output) do
+    output
+    |> String.split("\n", trim: true)
+    # The first line is the inspected file ("path:"), not a dependency.
+    |> Enum.filter(&String.starts_with?(&1, "\t"))
+    |> Enum.map(fn line ->
+      line
+      |> String.trim()
+      |> String.replace(~r/\s+\(compatibility version.*\)$/, "")
+      |> String.trim()
+    end)
+  end
+
+  @doc "True when a dylib path must be copied into the bundle (Homebrew/local)."
+  @spec external?(String.t()) :: boolean()
+  def external?(path) when is_binary(path) do
+    Enum.any?(@external_prefixes, &String.starts_with?(path, &1))
+  end
+
+  @doc "install_name_tool args to set a dylib's own id."
+  @spec id_args(String.t(), String.t()) :: [String.t()]
+  def id_args(dylib_path, new_id), do: ["-id", new_id, dylib_path]
+
+  @doc """
+  install_name_tool args to rewrite zero or more dependency install names on a
+  binary. Returns `[]` when there are no changes so callers can skip the tool.
+  """
+  @spec change_args(String.t(), [{String.t(), String.t()}]) :: [String.t()]
+  def change_args(_binary, []), do: []
+
+  def change_args(binary, changes) when is_list(changes) do
+    Enum.flat_map(changes, fn {old, new} -> ["-change", old, new] end) ++ [binary]
+  end
+
+  @doc """
+  Copy every external dylib reachable from `nif_path` into `frameworks_dir` and
+  rewrite all install names (in the NIF and the copied dylibs) to point inside
+  the bundle. Returns `{:ok, copied_paths}`.
+
+  References are made `@loader_path`-relative so they resolve against the binary
+  that triggers the load — independent of where the host process executable
+  lives (the release runs `beam.smp`, not the bundle launcher) and without any
+  `DYLD_*` env reliance:
+
+    * the NIF references each dylib as `<nif_loader_prefix>/<basename>`, where
+      `nif_loader_prefix` is the `@loader_path/../…/Frameworks` path from the
+      NIF's directory to `frameworks_dir`;
+    * the copied dylibs live together, so they reference each other (and their
+      own id) as `@loader_path/<basename>`.
+  """
+  @spec bundle(String.t(), String.t(), String.t()) ::
+          {:ok, [String.t()]} | {:error, term()}
+  def bundle(nif_path, frameworks_dir, nif_loader_prefix) do
+    File.mkdir_p!(frameworks_dir)
+
+    with {:ok, {_seen, externals}} <- collect(nif_path, MapSet.new(), []) do
+      copied =
+        externals
+        |> Enum.reverse()
+        |> Enum.map(fn src ->
+          dest = Path.join(frameworks_dir, Path.basename(src))
+          File.cp!(src, dest)
+          File.chmod!(dest, 0o644)
+          {src, dest}
+        end)
+
+      with :ok <- rewrite(nif_path, copied, nif_loader_prefix),
+           :ok <- rewrite_each(copied) do
+        {:ok, Enum.map(copied, &elem(&1, 1))}
+      end
+    end
+  end
+
+  # Depth-first transitive collection of external dependency paths. Returns
+  # `{:ok, {seen, acc}}` where `acc` is the reverse-discovery-order path list.
+  defp collect(binary, seen, acc) do
+    case otool(binary) do
+      {:ok, deps} ->
+        deps
+        |> Enum.filter(&external?/1)
+        |> Enum.reject(&MapSet.member?(seen, &1))
+        |> Enum.reduce_while({:ok, {seen, acc}}, fn dep, {:ok, {seen_acc, list_acc}} ->
+          seen_acc = MapSet.put(seen_acc, dep)
+
+          case collect(dep, seen_acc, [dep | list_acc]) do
+            {:ok, _} = ok -> {:cont, ok}
+            error -> {:halt, error}
+          end
+        end)
+
+      error ->
+        error
+    end
+  end
+
+  defp rewrite(binary, copied, prefix) do
+    changes =
+      Enum.map(copied, fn {src, dest} ->
+        {src, prefix <> "/" <> Path.basename(dest)}
+      end)
+
+    case change_args(binary, changes) do
+      [] -> :ok
+      args -> run("install_name_tool", args)
+    end
+  end
+
+  # Copied dylibs share Frameworks/, so they reference each other (and their own
+  # id) relative to their own location with @loader_path.
+  defp rewrite_each(copied) do
+    Enum.reduce_while(copied, :ok, fn {_src, dest}, _acc ->
+      base = Path.basename(dest)
+
+      with :ok <- run("install_name_tool", id_args(dest, "@loader_path/" <> base)),
+           :ok <- rewrite(dest, copied, "@loader_path") do
+        {:cont, :ok}
+      else
+        error -> {:halt, error}
+      end
+    end)
+  end
+
+  defp otool(path) do
+    case System.cmd("otool", ["-L", path], stderr_to_stdout: true) do
+      {out, 0} -> {:ok, parse_otool(out)}
+      {out, status} -> {:error, {:otool_failed, status, out}}
+    end
+  end
+
+  defp run(cmd, args) do
+    case System.cmd(cmd, args, stderr_to_stdout: true) do
+      {_out, 0} -> :ok
+      {out, status} -> {:error, {:command_failed, cmd, status, out}}
+    end
+  end
+end

lib/bds/mac_bundle/icon.ex

@@ -0,0 +1,195 @@
+defmodule BDS.MacBundle.Icon do
+  @moduledoc """
+  Builds the macOS `AppIcon.icns` for the bDS2 bundle.
+
+  The source artwork is the legacy app's pen icon (a gold pen on a gold disc,
+  imported as `priv/desktop/macos/icon-source.svg`). The bundle icon recolours
+  the **blue** pen to **red** by rotating any colour whose hue sits in the blue
+  band, leaving the gold body and warm/neutral tones untouched. Recolouring the
+  SVG text is fully deterministic and unit-testable; rasterisation then uses the
+  bundled libvips (`Image`) so no extra system tooling is required for SVG→PNG.
+
+  `.icns` packaging itself shells out to the macOS-only `sips`/`iconutil`.
+  """
+
+  # Hue band (degrees) that counts as "blue" and gets rotated to red.
+  @blue_low 195
+  @blue_high 265
+  # Rotation that maps the pen's ~218–221° blues onto ~358–1° (red).
+  @hue_shift 220
+
+  # Standard macOS iconset base sizes; each is emitted at @1x and @2x.
+  @iconset_sizes [16, 32, 128, 256, 512]
+
+  @doc "Absolute path to the (blue) source SVG bundled in priv."
+  @spec source_svg_path() :: String.t()
+  def source_svg_path do
+    Application.get_env(:bds, :mac_icon_source_svg) ||
+      Path.join(:code.priv_dir(:bds), "desktop/macos/icon-source.svg")
+  end
+
+  @doc "Default output path for the generated `.icns`."
+  @spec icns_path() :: String.t()
+  def icns_path, do: Path.join(:code.priv_dir(:bds), "desktop/macos/AppIcon.icns")
+
+  @doc """
+  Recolour a single `#RRGGBB` value. Blue-band colours are hue-rotated to red;
+  everything else is returned unchanged (byte-for-byte, no rounding drift).
+  """
+  @spec recolor_color(String.t()) :: String.t()
+  def recolor_color("#" <> _ = hex) do
+    {r, g, b} = to_rgb(hex)
+    {h, s, l} = rgb_to_hsl(r, g, b)
+
+    if h >= @blue_low and h < @blue_high do
+      new_h = :math.fmod(h - @hue_shift + 360.0, 360.0)
+      {nr, ng, nb} = hsl_to_rgb(new_h, s, l)
+      to_hex(nr, ng, nb)
+    else
+      String.upcase(hex)
+    end
+  end
+
+  @doc "Recolour every `#RRGGBB` literal found in an SVG (or any text)."
+  @spec recolor_svg(String.t()) :: String.t()
+  def recolor_svg(svg) when is_binary(svg) do
+    Regex.replace(~r/#[0-9A-Fa-f]{6}/, svg, fn hex -> recolor_color(hex) end)
+  end
+
+  @doc """
+  Generate the `.icns` from the source SVG. Returns `{:ok, icns_path}`.
+
+  Steps: recolour SVG → render a 1024² PNG via libvips → emit the iconset sizes
+  with `sips` → pack with `iconutil`.
+  """
+  @spec generate(keyword()) :: {:ok, String.t()} | {:error, term()}
+  def generate(opts \\ []) do
+    source = Keyword.get(opts, :source_svg, source_svg_path())
+    icns = Keyword.get(opts, :icns_path, icns_path())
+    png_1024 = Keyword.get(opts, :png_path, Path.rootname(icns) <> "-1024.png")
+
+    with {:ok, svg} <- File.read(source),
+         :ok <- render_png(recolor_svg(svg), png_1024, 1024),
+         {:ok, iconset} <- build_iconset(png_1024),
+         :ok <- run("iconutil", ["-c", "icns", "-o", icns, iconset]) do
+      File.rm_rf(iconset)
+      {:ok, icns}
+    end
+  end
+
+  @doc "Render an SVG string to a square PNG of `size` pixels via libvips."
+  @spec render_png(String.t(), String.t(), pos_integer()) :: :ok | {:error, term()}
+  def render_png(svg, png_path, size) do
+    with {:ok, image} <- Image.from_binary(svg),
+         {:ok, resized} <- Image.thumbnail(image, size, height: size),
+         {:ok, _} <- Image.write(resized, png_path) do
+      :ok
+    end
+  end
+
+  defp build_iconset(png_1024) do
+    iconset = Path.rootname(png_1024) <> ".iconset"
+    File.rm_rf!(iconset)
+    File.mkdir_p!(iconset)
+
+    Enum.reduce_while(@iconset_sizes, {:ok, iconset}, fn base, acc ->
+      with :ok <- emit_size(png_1024, iconset, base, 1),
+           :ok <- emit_size(png_1024, iconset, base, 2) do
+        {:cont, acc}
+      else
+        error -> {:halt, error}
+      end
+    end)
+  end
+
+  defp emit_size(png_1024, iconset, base, scale) do
+    px = base * scale
+    suffix = if scale == 1, do: "#{base}x#{base}", else: "#{base}x#{base}@2x"
+    out = Path.join(iconset, "icon_#{suffix}.png")
+    run("sips", ["-z", Integer.to_string(px), Integer.to_string(px), png_1024, "--out", out])
+  end
+
+  defp run(cmd, args) do
+    case System.cmd(cmd, args, stderr_to_stdout: true) do
+      {_out, 0} -> :ok
+      {out, status} -> {:error, {:command_failed, cmd, status, out}}
+    end
+  end
+
+  # ---- colour space helpers -------------------------------------------------
+
+  defp to_rgb("#" <> hex) do
+    {
+      String.to_integer(String.slice(hex, 0, 2), 16),
+      String.to_integer(String.slice(hex, 2, 2), 16),
+      String.to_integer(String.slice(hex, 4, 2), 16)
+    }
+  end
+
+  defp to_hex(r, g, b) do
+    "#" <> pad(r) <> pad(g) <> pad(b)
+  end
+
+  defp pad(v) do
+    v
+    |> max(0)
+    |> min(255)
+    |> Integer.to_string(16)
+    |> String.upcase()
+    |> String.pad_leading(2, "0")
+  end
+
+  defp rgb_to_hsl(r, g, b) do
+    rf = r / 255.0
+    gf = g / 255.0
+    bf = b / 255.0
+
+    max = Enum.max([rf, gf, bf])
+    min = Enum.min([rf, gf, bf])
+    l = (max + min) / 2.0
+    d = max - min
+
+    if d == 0.0 do
+      {0.0, 0.0, l}
+    else
+      s = if l > 0.5, do: d / (2.0 - max - min), else: d / (max + min)
+
+      h =
+        cond do
+          max == rf -> :math.fmod((gf - bf) / d + 6.0, 6.0)
+          max == gf -> (bf - rf) / d + 2.0
+          true -> (rf - gf) / d + 4.0
+        end
+
+      {h * 60.0, s, l}
+    end
+  end
+
+  defp hsl_to_rgb(_h, s, l) when s == 0.0 do
+    v = round(l * 255.0)
+    {v, v, v}
+  end
+
+  defp hsl_to_rgb(h, s, l) do
+    q = if l < 0.5, do: l * (1.0 + s), else: l + s - l * s
+    p = 2.0 * l - q
+    hk = h / 360.0
+
+    {
+      round(hue_to_channel(p, q, hk + 1.0 / 3.0) * 255.0),
+      round(hue_to_channel(p, q, hk) * 255.0),
+      round(hue_to_channel(p, q, hk - 1.0 / 3.0) * 255.0)
+    }
+  end
+
+  defp hue_to_channel(p, q, t) do
+    t = :math.fmod(t + 1.0, 1.0)
+
+    cond do
+      t < 1.0 / 6.0 -> p + (q - p) * 6.0 * t
+      t < 1.0 / 2.0 -> q
+      t < 2.0 / 3.0 -> p + (q - p) * (2.0 / 3.0 - t) * 6.0
+      true -> p
+    end
+  end
+end

lib/mix/tasks/bds.bundle.macos.ex

@@ -0,0 +1,98 @@
+defmodule Mix.Tasks.Bds.Bundle.Macos do
+  @moduledoc """
+  Build a self-contained, ad-hoc-signed `BDS2.app` macOS bundle.
+
+      mix bds.bundle.macos [--app-release PATH] [--output DIR] [--version V]
+                           [--regen-icon] [--register] [--no-codesign]
+
+  Assumes the `:bds` release has been built (`MIX_ENV=prod mix release bds`); pass
+  `--app-release` to point elsewhere. Generates the red-pen icon on first run (or
+  with `--regen-icon`), assembles the bundle, relocates the wxWidgets dylibs so it
+  runs on a clean Mac, ad-hoc codesigns it, and (with `--register`) registers the
+  `bds2://` URL scheme via LaunchServices.
+  """
+
+  use Mix.Task
+
+  alias BDS.MacBundle
+  alias BDS.MacBundle.Icon
+
+  @shortdoc "Builds a self-contained macOS .app bundle (BDS2.app)"
+
+  @lsregister "/System/Library/Frameworks/CoreServices.framework/Frameworks/LaunchServices.framework/Support/lsregister"
+
+  @impl Mix.Task
+  def run(args) do
+    unless match?({:unix, :darwin}, :os.type()) do
+      Mix.raise("mix bds.bundle.macos only runs on macOS")
+    end
+
+    {opts, _positional, _invalid} =
+      OptionParser.parse(args,
+        strict: [
+          app_release: :string,
+          output: :string,
+          version: :string,
+          regen_icon: :boolean,
+          register: :boolean,
+          codesign: :boolean
+        ]
+      )
+
+    Mix.Task.run("app.config")
+
+    version = opts[:version] || Mix.Project.config()[:version]
+    env_name = Atom.to_string(Mix.env())
+    release_dir = opts[:app_release] || Path.expand("_build/#{env_name}/rel/bds", File.cwd!())
+    output_dir = opts[:output] || Path.expand("dist/macos", File.cwd!())
+
+    unless File.dir?(release_dir) do
+      Mix.raise("Release not found at #{release_dir}. Run `MIX_ENV=prod mix release bds` first.")
+    end
+
+    icns = ensure_icon(opts[:regen_icon] == true)
+
+    Mix.shell().info("Assembling BDS2.app (version #{version})…")
+
+    case MacBundle.assemble(
+           release_dir: release_dir,
+           output_dir: output_dir,
+           icns_path: icns,
+           version: version,
+           skip_codesign: opts[:codesign] == false
+         ) do
+      {:ok, app} ->
+        maybe_register(app, opts[:register] == true)
+        Mix.shell().info("Built #{app}")
+
+      {:error, reason} ->
+        Mix.raise("Bundle failed: #{inspect(reason)}")
+    end
+  end
+
+  defp ensure_icon(regen?) do
+    icns = Icon.icns_path()
+
+    if regen? or not File.exists?(icns) do
+      Mix.shell().info("Generating AppIcon.icns (blue→red)…")
+
+      case Icon.generate() do
+        {:ok, path} -> path
+        {:error, reason} -> Mix.raise("Icon generation failed: #{inspect(reason)}")
+      end
+    else
+      icns
+    end
+  end
+
+  defp maybe_register(_app, false), do: :ok
+
+  defp maybe_register(app, true) do
+    if File.exists?(@lsregister) do
+      System.cmd(@lsregister, ["-f", app])
+      Mix.shell().info("Registered bds2:// scheme via LaunchServices")
+    else
+      Mix.shell().info("lsregister not found; skip scheme registration")
+    end
+  end
+end

priv/desktop/macos/Info.plist.eex

@@ -0,0 +1,45 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+    <key>CFBundleDevelopmentRegion</key>
+    <string>en</string>
+    <key>CFBundleDisplayName</key>
+    <string><%= name %></string>
+    <key>CFBundleName</key>
+    <string><%= name %></string>
+    <key>CFBundleIdentifier</key>
+    <string><%= identifier %></string>
+    <key>CFBundleExecutable</key>
+    <string><%= executable %></string>
+    <key>CFBundleIconFile</key>
+    <string><%= icon %></string>
+    <key>CFBundlePackageType</key>
+    <string>APPL</string>
+    <key>CFBundleSignature</key>
+    <string>????</string>
+    <key>CFBundleShortVersionString</key>
+    <string><%= version %></string>
+    <key>CFBundleVersion</key>
+    <string><%= version %></string>
+    <key>LSMinimumSystemVersion</key>
+    <string><%= min_system %></string>
+    <key>NSHighResolutionCapable</key>
+    <true/>
+    <key>LSApplicationCategoryType</key>
+    <string>public.app-category.developer-tools</string>
+    <key>CFBundleURLTypes</key>
+    <array>
+        <dict>
+            <key>CFBundleTypeRole</key>
+            <string>Editor</string>
+            <key>CFBundleURLName</key>
+            <string>bDS2 Blogmark Links</string>
+            <key>CFBundleURLSchemes</key>
+            <array>
+                <string><%= scheme %></string>
+            </array>
+        </dict>
+    </array>
+</dict>
+</plist>

priv/desktop/macos/icon-source.svg

@@ -0,0 +1,71 @@
+<svg xmlns="http://www.w3.org/2000/svg" width="1024" height="1024" viewBox="0 0 1024 1024">
+  <defs>
+    <radialGradient id="goldBase" cx="36%" cy="24%" r="88%">
+      <stop offset="0%" stop-color="#FCE9A4"/>
+      <stop offset="22%" stop-color="#E8C96A"/>
+      <stop offset="52%" stop-color="#C59A33"/>
+      <stop offset="78%" stop-color="#9B741F"/>
+      <stop offset="100%" stop-color="#6E4E14"/>
+    </radialGradient>
+    <linearGradient id="goldSheen" x1="0%" y1="0%" x2="100%" y2="100%">
+      <stop offset="0%" stop-color="#FFF8D8" stop-opacity="0.64"/>
+      <stop offset="33%" stop-color="#F7E2A5" stop-opacity="0.08"/>
+      <stop offset="62%" stop-color="#FFFFFF" stop-opacity="0.28"/>
+      <stop offset="100%" stop-color="#7D5A1A" stop-opacity="0"/>
+    </linearGradient>
+    <linearGradient id="penBody" x1="0%" y1="0%" x2="100%" y2="100%">
+      <stop offset="0%" stop-color="#6FA3FF"/>
+      <stop offset="50%" stop-color="#2B61CE"/>
+      <stop offset="100%" stop-color="#1D4294"/>
+    </linearGradient>
+    <linearGradient id="penMetal" x1="0%" y1="0%" x2="0%" y2="100%">
+      <stop offset="0%" stop-color="#FBFCFF"/>
+      <stop offset="45%" stop-color="#C6D0E2"/>
+      <stop offset="100%" stop-color="#8E9AB1"/>
+    </linearGradient>
+    <filter id="scratch" x="-10%" y="-10%" width="120%" height="120%">
+      <feTurbulence type="fractalNoise" baseFrequency="0.95" numOctaves="1" seed="7" result="noise"/>
+      <feDisplacementMap in="SourceGraphic" in2="noise" scale="2.8" xChannelSelector="R" yChannelSelector="G"/>
+    </filter>
+  </defs>
+
+  <rect width="1024" height="1024" rx="224" fill="url(#goldBase)"/>
+  <path d="M44 188 Q312 76 510 180 T980 164" fill="none" stroke="#FFF4C8" stroke-opacity="0.58" stroke-width="84" stroke-linecap="round"/>
+  <rect width="1024" height="1024" rx="224" fill="url(#goldSheen)"/>
+
+  <g fill="none" stroke="#0D0D0D" stroke-linecap="round" stroke-linejoin="round" filter="url(#scratch)">
+    <path d="M130 884 L512 118 L894 884 Z" stroke-width="34"/>
+    <path d="M116 896 L518 108 L908 892" stroke-width="8" opacity="0.66"/>
+    <path d="M142 876 L506 128 L882 876" stroke-width="7" opacity="0.54"/>
+
+    <path d="M176 884 Q354 868 560 860" stroke-width="24"/>
+    <path d="M168 892 Q362 876 562 866" stroke-width="8" opacity="0.62"/>
+    <path d="M568 862 Q704 862 848 882" stroke-width="7" opacity="0.3"/>
+
+    <path d="M322 646 Q512 610 706 646" stroke-width="20"/>
+    <path d="M306 656 Q512 620 722 656" stroke-width="7" opacity="0.6"/>
+
+    <path d="M408 438 Q512 418 616 438" stroke-width="16"/>
+    <path d="M396 448 Q512 426 628 448" stroke-width="6" opacity="0.64"/>
+
+    <path d="M372 530 Q512 446 652 530" stroke-width="18"/>
+    <path d="M372 530 Q512 614 652 530" stroke-width="18"/>
+    <path d="M392 530 Q512 462 632 530" stroke-width="6" opacity="0.64"/>
+    <path d="M392 530 Q512 598 632 530" stroke-width="6" opacity="0.64"/>
+    <circle cx="512" cy="530" r="34" stroke-width="18"/>
+    <circle cx="512" cy="530" r="12" stroke-width="6" opacity="0.68"/>
+  </g>
+
+  <g transform="rotate(-44 560 860)">
+    <path d="M653.75 811.25 L1088.75 811.25 C1126.25 811.25 1156.25 833.75 1156.25 860 C1156.25 886.25 1126.25 908.75 1088.75 908.75 L653.75 908.75 Z" fill="url(#penBody)"/>
+    <path d="M653.75 811.25 L747.5 811.25 C773.75 811.25 792.5 833.75 792.5 860 C792.5 886.25 773.75 908.75 747.5 908.75 L653.75 908.75 Z" fill="#7FB0FF"/>
+    <rect x="788.75" y="811.25" width="37.5" height="97.5" rx="15" fill="#214A9D"/>
+    <path d="M826.25 833.75 Q935 803.75 1040 833.75" fill="none" stroke="#9FC2FF" stroke-width="11.25"/>
+    <path d="M560 860 L608.75 830 L653.75 860 L608.75 890 Z" fill="url(#penMetal)"/>
+    <path d="M560 860 L537.5 845 L537.5 875 Z" fill="#101318"/>
+    <line x1="560" y1="860" x2="638.75" y2="860" stroke="#4D5C78" stroke-width="5.6"/>
+    <circle cx="601.25" cy="860" r="8.4" fill="#5A6780"/>
+  </g>
+
+  <path d="M172 886 Q356 872 560 860" fill="none" stroke="#0C0C0C" stroke-width="10" stroke-linecap="round"/>
+</svg>

priv/desktop/macos/launcher.sh.eex

@@ -0,0 +1,17 @@
+#!/bin/sh
+# Launcher for <%= name %> (<%= identifier %>).
+# Generated by mix bds.bundle.macos — do not edit inside the .app.
+#
+# Resolves the bundle's own location and execs the embedded Elixir release.
+# wxWidgets dylibs live in ../Frameworks and are referenced via @loader_path, so
+# the app is self-contained regardless of where the BEAM executable runs from.
+set -e
+
+HERE="$(cd "$(dirname "$0")" && pwd)"
+APP_CONTENTS="$(cd "$HERE/.." && pwd)"
+RELEASE_ROOT="$APP_CONTENTS/Resources/rel"
+
+# Belt-and-suspenders fallback for dyld (primary resolution is @loader_path).
+export DYLD_FALLBACK_LIBRARY_PATH="$APP_CONTENTS/Frameworks:${DYLD_FALLBACK_LIBRARY_PATH:-}"
+
+exec "$RELEASE_ROOT/bin/<%= release_name %>" start

test/bds/mac_bundle_test.exs

@@ -0,0 +1,238 @@
+defmodule BDS.MacBundleTest do
+  use ExUnit.Case, async: true
+
+  import Bitwise
+
+  alias BDS.MacBundle
+  alias BDS.MacBundle.Dylibs
+  alias BDS.MacBundle.Icon
+
+  # Parse "#RRGGBB" into {r, g, b} for property assertions in tests.
+  defp rgb("#" <> hex) do
+    {r, g, b} = {String.slice(hex, 0, 2), String.slice(hex, 2, 2), String.slice(hex, 4, 2)}
+    {String.to_integer(r, 16), String.to_integer(g, 16), String.to_integer(b, 16)}
+  end
+
+  describe "Icon.recolor_color/1" do
+    test "turns the saturated blue pen colors red (red channel becomes dominant)" do
+      for blue <- ~w(#1D4294 #214A9D #2B61CE #6FA3FF #7FB0FF #9FC2FF) do
+        recolored = Icon.recolor_color(blue)
+        {ir, _ig, ib} = rgb(blue)
+        {r, _g, b} = rgb(recolored)
+
+        assert ib > ir, "expected #{blue} to start blue-dominant"
+        assert r > b, "expected #{blue} -> #{recolored} to become red-dominant"
+      end
+    end
+
+    test "leaves gold / warm colors unchanged" do
+      for gold <- ~w(#FCE9A4 #E8C96A #C59A33 #9B741F #6E4E14 #FFF4C8) do
+        assert Icon.recolor_color(gold) == gold
+      end
+    end
+
+    test "leaves pure white and near-black unchanged" do
+      assert Icon.recolor_color("#FFFFFF") == "#FFFFFF"
+      assert Icon.recolor_color("#0D0D0D") == "#0D0D0D"
+    end
+
+    test "is case-insensitive on input and returns uppercase hex" do
+      assert Icon.recolor_color("#2b61ce") == Icon.recolor_color("#2B61CE")
+      assert Icon.recolor_color("#2b61ce") =~ ~r/^#[0-9A-F]{6}$/
+    end
+  end
+
+  describe "Icon.recolor_svg/1" do
+    test "replaces every blue hex in the source SVG and keeps gold stops" do
+      svg = File.read!(Icon.source_svg_path())
+      recolored = Icon.recolor_svg(svg)
+
+      refute recolored =~ "#2B61CE"
+      refute recolored =~ "#1D4294"
+      refute recolored =~ "#9FC2FF"
+      # gold base gradient stops survive untouched
+      assert recolored =~ "#E8C96A"
+      assert recolored =~ "#C59A33"
+    end
+  end
+
+  describe "Icon.generate/1 (real libvips + sips + iconutil pipeline)" do
+    @describetag :macos_tools
+
+    test "renders the recoloured SVG and packs a valid .icns" do
+      tmp = Path.join(System.tmp_dir!(), "bds-icon-#{System.unique_integer([:positive])}")
+      File.mkdir_p!(tmp)
+      on_exit(fn -> File.rm_rf!(tmp) end)
+
+      icns = Path.join(tmp, "AppIcon.icns")
+      png = Path.join(tmp, "AppIcon-1024.png")
+
+      assert {:ok, ^icns} = Icon.generate(icns_path: icns, png_path: png)
+      assert File.exists?(icns)
+      # .icns files begin with the "icns" magic.
+      assert File.read!(icns) |> binary_part(0, 4) == "icns"
+      # 1024² master PNG was produced.
+      assert {:ok, img} = Image.open(png)
+      assert Image.width(img) == 1024
+    end
+  end
+
+  describe "MacBundle.info_plist/1" do
+    setup do
+      %{plist: MacBundle.info_plist(version: "1.2.3")}
+    end
+
+    test "registers the bds2 URL scheme", %{plist: plist} do
+      assert plist =~ "CFBundleURLSchemes"
+      assert plist =~ "<string>bds2</string>"
+    end
+
+    test "carries the confirmed bundle identity", %{plist: plist} do
+      assert plist =~ "<string>de.rfc1437.bds2</string>"
+      assert plist =~ "<key>CFBundleExecutable</key>"
+      assert plist =~ "<string>bds2</string>"
+      assert plist =~ "<string>AppIcon</string>"
+      assert plist =~ "<string>1.2.3</string>"
+    end
+
+    test "is well-formed XML/plist" do
+      assert plist = MacBundle.info_plist(version: "0.0.1")
+      assert String.starts_with?(plist, "<?xml")
+      assert plist =~ "<!DOCTYPE plist"
+      assert plist =~ "</plist>"
+    end
+  end
+
+  describe "MacBundle.relative_up/2" do
+    test "computes the ../-style hop from the wx NIF dir up to Frameworks" do
+      nif_dir = "/x/BDS2.app/Contents/Resources/rel/lib/wx-2.5/priv"
+      frameworks = "/x/BDS2.app/Contents/Frameworks"
+      assert MacBundle.relative_up(nif_dir, frameworks) == "../../../../../Frameworks"
+    end
+
+    test "siblings resolve with a single hop" do
+      assert MacBundle.relative_up("/a/b/c", "/a/b/d") == "../d"
+    end
+  end
+
+  describe "Dylibs.parse_otool/1 and external?/1" do
+    test "extracts the dependency paths, dropping the header line" do
+      output =
+        Enum.join(
+          [
+            "/abs/path/wxe_driver.so:",
+            "\t/opt/homebrew/opt/wxwidgets/lib/libwx_baseu-3.2.dylib (compatibility version 0.0.0, current version 0.0.0)",
+            "\t/usr/lib/libSystem.B.dylib (compatibility version 1.0.0, current version 1.0.0)",
+            "\t@rpath/libwx_osx_cocoau_core-3.2.dylib (compatibility version 0.0.0, current version 0.0.0)"
+          ],
+          "\n"
+        )
+
+      assert Dylibs.parse_otool(output) == [
+               "/opt/homebrew/opt/wxwidgets/lib/libwx_baseu-3.2.dylib",
+               "/usr/lib/libSystem.B.dylib",
+               "@rpath/libwx_osx_cocoau_core-3.2.dylib"
+             ]
+    end
+
+    test "treats Homebrew prefixes as external and system/rpath as internal" do
+      assert Dylibs.external?("/opt/homebrew/opt/wxwidgets/lib/libwx_baseu-3.2.dylib")
+      assert Dylibs.external?("/usr/local/lib/libpng16.dylib")
+      refute Dylibs.external?("/usr/lib/libSystem.B.dylib")
+      refute Dylibs.external?("/System/Library/Frameworks/Cocoa.framework/Cocoa")
+      refute Dylibs.external?("@rpath/libwx_osx_cocoau_core-3.2.dylib")
+      refute Dylibs.external?("@executable_path/../Frameworks/libfoo.dylib")
+    end
+  end
+
+  describe "Dylibs install_name_tool arg builders" do
+    test "id_args/2" do
+      assert Dylibs.id_args("/Frameworks/libfoo.dylib", "@rpath/libfoo.dylib") ==
+               ["-id", "@rpath/libfoo.dylib", "/Frameworks/libfoo.dylib"]
+    end
+
+    test "change_args/2 batches multiple -change pairs before the target binary" do
+      changes = [
+        {"/opt/homebrew/lib/a.dylib", "@executable_path/../Frameworks/a.dylib"},
+        {"/opt/homebrew/lib/b.dylib", "@executable_path/../Frameworks/b.dylib"}
+      ]
+
+      assert Dylibs.change_args("/app/MacOS/bds2", changes) ==
+               [
+                 "-change",
+                 "/opt/homebrew/lib/a.dylib",
+                 "@executable_path/../Frameworks/a.dylib",
+                 "-change",
+                 "/opt/homebrew/lib/b.dylib",
+                 "@executable_path/../Frameworks/b.dylib",
+                 "/app/MacOS/bds2"
+               ]
+    end
+
+    test "change_args/2 with no changes is an empty list (no-op, do not invoke the tool)" do
+      assert Dylibs.change_args("/app/MacOS/bds2", []) == []
+    end
+  end
+
+  describe "MacBundle.assemble/1" do
+    setup do
+      tmp = Path.join(System.tmp_dir!(), "bds-macbundle-#{System.unique_integer([:positive])}")
+      release = Path.join(tmp, "rel")
+      File.mkdir_p!(Path.join(release, "bin"))
+      File.write!(Path.join(release, "bin/bds"), "#!/bin/sh\necho fake release\n")
+      File.mkdir_p!(Path.join(release, "lib/wx-2.4/priv"))
+      File.write!(Path.join(release, "lib/wx-2.4/priv/wxe_driver.so"), "fake-nif")
+
+      icns = Path.join(tmp, "AppIcon.icns")
+      File.write!(icns, "fake-icns")
+
+      output = Path.join(tmp, "dist")
+
+      on_exit(fn -> File.rm_rf!(tmp) end)
+
+      {:ok, app} =
+        MacBundle.assemble(
+          release_dir: release,
+          output_dir: output,
+          icns_path: icns,
+          version: "0.1.0",
+          skip_dylibs: true,
+          skip_codesign: true
+        )
+
+      %{app: app}
+    end
+
+    test "produces a BDS2.app with the standard Contents layout", %{app: app} do
+      assert Path.basename(app) == "BDS2.app"
+      assert File.dir?(Path.join(app, "Contents/MacOS"))
+      assert File.dir?(Path.join(app, "Contents/Resources"))
+      assert File.dir?(Path.join(app, "Contents/Frameworks"))
+    end
+
+    test "writes Info.plist with the bds2 scheme", %{app: app} do
+      plist = File.read!(Path.join(app, "Contents/Info.plist"))
+      assert plist =~ "<string>bds2</string>"
+      assert plist =~ "<string>de.rfc1437.bds2</string>"
+    end
+
+    test "writes the PkgInfo file", %{app: app} do
+      assert File.read!(Path.join(app, "Contents/PkgInfo")) == "APPL????"
+    end
+
+    test "installs an executable launcher that execs the release", %{app: app} do
+      launcher = Path.join(app, "Contents/MacOS/bds2")
+      assert File.exists?(launcher)
+      %File.Stat{mode: mode} = File.stat!(launcher)
+      assert (mode &&& 0o111) != 0, "launcher must be executable"
+      script = File.read!(launcher)
+      assert script =~ "Resources/rel"
+      assert script =~ "bin/bds"
+    end
+
+    test "copies the release tree and the icon into Resources", %{app: app} do
+      assert File.exists?(Path.join(app, "Contents/Resources/rel/bin/bds"))
+      assert File.exists?(Path.join(app, "Contents/Resources/AppIcon.icns"))
+    end
+  end
+end