app: package the desktop app as the web build, and delete the Linux embedder

Completes the move: `linux/` is gone, replaced by the web build served by the
wrapper in a Chrome `--app` window. The icons and the .desktop installer move
out of `linux/` first -- they are not Flutter scaffolding and are still
needed; the entry now points at the packaged launcher and matches the
`--class=diet_guard_app` the wrapper passes, so the taskbar shows the app's
icon rather than a browser's.

install_arch.sh carries over the three traps each of which produced an
install that looked fine until launched: `dart build cli` rather than
`dart compile exe` (which refuses any package whose dependency graph has
native build hooks), `options=('!strip')` (makepkg would otherwise discard
the AOT snapshot, leaving a binary that runs as the bare Dart VM printing a
usage message), and no browser in `depends` (this machine's policy uninstalls
`chromium` seconds later, failing dependency resolution).

Also adds the frame-cadence instrument the performance claim is measured
with, armed by `--dart-define=DIET_GUARD_FRAME_STATS=1` and read with
`String.fromEnvironment` -- `bool.fromEnvironment` only accepts the literal
`true`, so `=1` would evaluate to false and a whole run would silently
produce no data. It reports frame-to-frame cadence rather than build/raster
durations, since work that fits the budget says nothing about the frame rate
actually achieved.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

CLAUDE.md

@@ -113,6 +113,40 @@ silently does **not** reach the running service.
   private `kuhyx/syncs` GitHub repo (see "Cross-device sync" above)
   and `~/.config/diet_guard/sync_token`.
 
+## The companion app's desktop target is a web build
+
+`app/` builds for two platforms, and only two: **Android** (the phone) and
+**web** (the Linux desktop). There is no `app/linux/` — Flutter's GTK embedder
+manages only ~20fps at 3840x2160 (measured on a stock `flutter create` app, so
+it is the toolkit, not this code), where the same Dart in Chrome sustains
+~144fps; see `~/todo/docs/desktop-performance-findings.md`. On the desktop the
+app is the web build served by `bin/diet_guard_desktop.dart` and shown in a
+Chrome `--app` window.
+
+Consequences worth knowing before touching `app/`:
+
+- **`dart:io` does not fail a web *compile*** — it becomes a stub that throws
+  at runtime, so the symptom is a blank white window, not a build error. Every
+  platform-specific edge goes behind a conditional export
+  (`document_store*.dart`, `blob_store*.dart`, `background_tasks*.dart`,
+  `notification_backend*.dart`, `token_vault*.dart`,
+  `github_client_factory*.dart`, `attached_image*.dart`). Branch on `kIsWeb`
+  *before* any `Platform.is…`, which itself throws on web.
+- **The port and the Chrome `--user-data-dir` are fixed on purpose**
+  (`lib/services/desktop_wrapper.dart`). IndexedDB is keyed by origin and
+  lives in that profile: changing either hides the entire local food log.
+- **The wrapper holds the GitHub token**, not the browser, and proxies
+  `api.github.com` plus the CORS-less device flow (`lib/desktop/github_proxy.dart`).
+- **The desktop pushes as device id `desktop`**, the phone as `phone`, the
+  Python side as `pc`. Sharing an id means two devices overwrite each other's
+  pushed log every tick.
+- **Desktop reminders only exist while the window is open.** A browser has no
+  WorkManager equivalent; the PC's real backstop is `diet-guard-gate.timer`,
+  which locks the screen. Don't "fix" this with a background service without
+  deciding you want a new daemon.
+- `flutter create --platforms linux` would silently restore the slow path.
+  Don't run it in `app/`.
+
 ## Commands
 
 - Run tests: `python -m pytest diet_guard/tests/ --cov=diet_guard --cov-branch --cov-fail-under=100`
@@ -120,6 +154,11 @@ silently does **not** reach the running service.
 - Test the lock manually (safe, closeable): `python -m diet_guard gate --demo`
 - Run one sync tick manually: `python -m diet_guard sync`
 - Install for production: `bash install.sh`
+- App tests: `cd app && flutter test`
+- Run the desktop app from the repo: `cd app && bash run.sh`
+- Install the desktop app (Arch package + .desktop entry):
+  `cd app && bash install_arch.sh`
+- Build the phone app: `cd app && flutter build apk --release`
 
 ## Do NOT
 
@@ -131,6 +170,9 @@ silently does **not** reach the running service.
 - Don't reintroduce a seal/lock/`chattr +i` on the budget file as a "fix" —
   it was deliberately removed so the budget is freely editable and synced
   between devices; see "Operational gotchas" above.
+- Don't re-add a Linux embedder target to `app/`, and don't change the
+  wrapper's fixed port or Chrome profile path — see "The companion app's
+  desktop target is a web build" above.
 
 ## Flutter/Dart AI rules
 

app/desktop/install_desktop_entry.sh

@@ -1,34 +1,34 @@
 #!/bin/bash
 
 # ============================================================================
-# Install the diet_guard_app launcher icon and .desktop entry for the Linux desktop.
+# Install the diet_guard_app launcher icon and .desktop entry for the Linux
+# desktop.
 #
-# Flutter's GTK runner has no icon of its own: my_application.cc calls
-# gtk_window_set_icon_name("diet-guard-app"), which resolves through the hicolor icon
-# theme. This script is what puts the icon into that theme, plus a .desktop
-# entry so the app appears in application menus.
+# The desktop app is a Flutter *web* build shown in a Chrome app window (the
+# Linux embedder manages only ~20fps at 4K), so the launcher starts the
+# wrapper, which serves the build and opens the browser.
 #
-# Icon PNGs are pre-rendered and committed under linux/icons/, so this script
+# Icon PNGs are pre-rendered and committed under desktop/icons/, so this script
 # needs no image tooling at run time. Regenerate them with:
 #   PYTHONPATH=~/testsAndMisc python3 -m python_pkg.app_icons \
-#       generate --app diet_guard_app --linux-out linux/icons
+#       generate --app diet_guard_app --linux-out desktop/icons
 # ============================================================================
 
 set -euo pipefail
 
 SCRIPT_NAME="$(basename "$0")"
-LINUX_DIR="$(cd "$(dirname "$0")" && pwd)"
-REPO_DIR="$(dirname "$LINUX_DIR")"
-readonly SCRIPT_NAME LINUX_DIR REPO_DIR
+DESKTOP_SRC_DIR="$(cd "$(dirname "$0")" && pwd)"
+readonly SCRIPT_NAME DESKTOP_SRC_DIR
 readonly ICON_NAME="diet-guard-app"
-readonly BINARY_NAME="diet_guard_app"
-# GTK derives WM_CLASS from the GApplication id in linux/CMakeLists.txt,
-# not from the binary name; verified with xprop on the running window.
-readonly WM_CLASS="com.kuhy.diet_guard_app"
-readonly ICON_SRC_DIR="$LINUX_DIR/icons"
+# Chrome sets WM_CLASS from --class, which the wrapper passes explicitly.
+# Without it the window inherits the browser's own class and the taskbar shows
+# a browser icon instead of this app's.
+readonly WM_CLASS="diet_guard_app"
+readonly ICON_SRC_DIR="$DESKTOP_SRC_DIR/icons"
 readonly ICON_THEME_DIR="${XDG_DATA_HOME:-$HOME/.local/share}/icons/hicolor"
 readonly DESKTOP_DIR="${XDG_DATA_HOME:-$HOME/.local/share}/applications"
-readonly BUNDLE_BIN="$REPO_DIR/build/linux/x64/release/bundle/$BINARY_NAME"
+# Installed by install_arch.sh; the repo copy is only used for development.
+readonly LAUNCHER="/usr/bin/diet-guard-app"
 
 usage() {
     echo "Usage: $SCRIPT_NAME"
@@ -79,7 +79,7 @@ install_desktop_entry() {
 Type=Application
 Name=diet guard
 Comment=Diet logging and budget companion
-Exec=$BUNDLE_BIN
+Exec=$LAUNCHER
 Icon=$ICON_NAME
 Terminal=false
 Categories=Utility;
@@ -97,9 +97,9 @@ main() {
     install_desktop_entry
     echo "Installed $ICON_NAME icon into $ICON_THEME_DIR"
     echo "Installed $DESKTOP_DIR/$ICON_NAME.desktop"
-    if [[ ! -x "$BUNDLE_BIN" ]]; then
-        echo "Note: $BUNDLE_BIN does not exist yet."
-        echo "      Run 'flutter build linux --release' to make the entry launchable."
+    if [[ ! -x "$LAUNCHER" ]]; then
+        echo "Note: $LAUNCHER does not exist yet."
+        echo "      Run 'bash install_arch.sh' to make the entry launchable."
     fi
 }
 

app/install_arch.sh

@@ -0,0 +1,86 @@
+#!/bin/bash
+# Builds the diet_guard companion app's desktop target and installs it as an
+# Arch Linux package via pacman.
+# Run from anywhere -- uses the directory of this script as the repo root.
+# Requires: flutter, base-devel (provides makepkg), sudo for pacman.
+
+set -euo pipefail
+
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+# The desktop app is a Flutter *web* build served by a small local wrapper:
+# Flutter's Linux embedder only reaches ~20fps at 4K, while the same Dart code
+# in Chrome sustains ~144fps.
+WEB_DIR="$SCRIPT_DIR/build/web"
+WRAPPER_BUNDLE="$SCRIPT_DIR/build/cli/bundle"
+WORK_DIR="$(mktemp -d)"
+
+cleanup() { rm -rf "$WORK_DIR"; }
+trap cleanup EXIT
+
+# Parse version from pubspec.yaml (strip build number: 1.0.0+1 -> 1.0.0)
+PKGVER="$(grep '^version:' "$SCRIPT_DIR/pubspec.yaml" \
+    | sed 's/^version:[[:space:]]*//' | sed 's/+.*//')"
+
+echo "==> Building diet_guard_app $PKGVER (Flutter web release)..."
+cd "$SCRIPT_DIR"
+flutter build web --release
+
+echo "==> Compiling the desktop wrapper..."
+# `dart build cli`, not `dart compile exe`: the package pulls in dependencies
+# with native build hooks, which `dart compile` refuses to handle even though
+# the wrapper itself uses none of them.
+rm -rf "$SCRIPT_DIR/build/cli"
+dart build cli -o "$SCRIPT_DIR/build/cli"
+
+echo "==> Generating PKGBUILD..."
+cat > "$WORK_DIR/PKGBUILD" <<EOF
+pkgname=diet-guard-app
+pkgver=$PKGVER
+pkgrel=1
+pkgdesc='Diet logging and budget companion for diet_guard'
+arch=('x86_64')
+url='https://github.com/kuhyx/diet-guard'
+license=('custom')
+# No hard browser dependency: naming one means makepkg installs it, and this
+# system has a policy that immediately removes 'chromium' again, which then
+# fails dependency resolution. The wrapper discovers whatever is present.
+depends=()
+optdepends=('google-chrome: renders the app window'
+            'chromium: renders the app window')
+# !strip is load-bearing: the wrapper is a Dart AOT executable with its
+# snapshot embedded in the ELF, and stripping discards it. The stripped binary
+# still runs, but is just the bare Dart VM printing a usage message.
+options=('!strip' '!debug')
+
+package() {
+    # Preserve the bundle's bin/ + lib/ layout: the executable loads its native
+    # libraries from ../lib and resolves the web assets from ../web.
+    install -dm755 "\$pkgdir/opt/diet-guard-app"
+    cp -r "$WRAPPER_BUNDLE/bin" "\$pkgdir/opt/diet-guard-app/bin"
+    # lib/ only exists when a dependency ships native code; copying it
+    # unconditionally would fail on a bundle that has none.
+    if [[ -d "$WRAPPER_BUNDLE/lib" ]]; then
+        cp -r "$WRAPPER_BUNDLE/lib" "\$pkgdir/opt/diet-guard-app/lib"
+    fi
+    chmod 755 "\$pkgdir/opt/diet-guard-app/bin/diet_guard_desktop"
+
+    install -dm755 "\$pkgdir/opt/diet-guard-app/web"
+    cp -r "$WEB_DIR/." "\$pkgdir/opt/diet-guard-app/web/"
+
+    install -dm755 "\$pkgdir/usr/bin"
+    cat > "\$pkgdir/usr/bin/diet-guard-app" <<'WRAPPER'
+#!/bin/bash
+exec /opt/diet-guard-app/bin/diet_guard_desktop "\$@"
+WRAPPER
+    chmod 755 "\$pkgdir/usr/bin/diet-guard-app"
+}
+EOF
+
+echo "==> Installing package via makepkg..."
+cd "$WORK_DIR"
+makepkg -sif --noconfirm
+
+echo "==> Installing the desktop entry..."
+"$SCRIPT_DIR/desktop/install_desktop_entry.sh"
+
+echo "==> Done. 'diet-guard-app' now runs version $PKGVER installed via pacman."

app/lib/main.dart

@@ -8,6 +8,7 @@ import 'package:diet_guard_app/screens/log_meal_screen.dart';
 import 'package:diet_guard_app/services/app_settings_service.dart';
 import 'package:diet_guard_app/services/background_tasks.dart';
 import 'package:diet_guard_app/services/foodbank_service.dart';
+import 'package:diet_guard_app/services/frame_stats.dart';
 import 'package:diet_guard_app/services/log_storage_service.dart';
 import 'package:diet_guard_app/services/notification_service.dart';
 import 'package:flutter/material.dart';
@@ -32,6 +33,10 @@ Future<void> main() async {
     }),
   );
   // coverage:ignore-end
+  // Off unless armed with --dart-define=DIET_GUARD_FRAME_STATS=1.
+  // coverage:ignore-start
+  if (frameStatsEnabled) startFrameStats();
+  // coverage:ignore-end
   runApp(const DietGuardApp());
 }
 

app/lib/services/frame_stats.dart

@@ -0,0 +1,75 @@
+/// Optional frame-cadence instrument, armed with
+/// `--dart-define=DIET_GUARD_FRAME_STATS=1`.
+///
+/// Reports **frame-to-frame cadence**, not build/raster durations: work that
+/// fits the budget says nothing about the frame rate actually achieved, which
+/// is the number the desktop migration exists to move.
+///
+/// Read with `String.fromEnvironment`, never `bool.fromEnvironment` -- the
+/// latter only accepts the literal `true`, so `=1` would silently evaluate to
+/// false and a whole measurement run would produce no data while looking like
+/// a broken callback.
+library;
+
+import 'dart:async';
+import 'dart:convert';
+import 'dart:ui' show FramePhase;
+
+import 'package:diet_guard_app/services/desktop_wrapper.dart';
+import 'package:flutter/scheduler.dart';
+import 'package:http/http.dart' as http;
+
+/// Whether the instrument is armed for this build.
+const frameStatsEnabled =
+    String.fromEnvironment('DIET_GUARD_FRAME_STATS') == '1';
+
+/// Starts collecting frame-to-frame intervals and periodically posts a
+/// summary to the desktop wrapper, which writes it to disk.
+///
+/// The wrapper is used as the sink because a browser cannot write a file and
+/// reading its console from outside needs a debugger attached; a POST lands
+/// somewhere a measurement run can simply read.
+// coverage:ignore-start
+void startFrameStats({Duration reportEvery = const Duration(seconds: 2)}) {
+  final intervalsMs = <double>[];
+  int? previousMicros;
+
+  SchedulerBinding.instance.addTimingsCallback((timings) {
+    for (final timing in timings) {
+      final micros = timing.timestampInMicroseconds(FramePhase.rasterFinish);
+      if (previousMicros != null) {
+        intervalsMs.add((micros - previousMicros!) / 1000);
+      }
+      previousMicros = micros;
+    }
+  });
+
+  Timer.periodic(reportEvery, (_) {
+    if (intervalsMs.isEmpty) return;
+    final sample = [...intervalsMs]..sort();
+    intervalsMs.clear();
+    double percentile(double fraction) =>
+        sample[(sample.length * fraction).floor().clamp(
+          0,
+          sample.length - 1,
+        )];
+    unawaited(
+      http.post(
+        Uri.parse(
+          '$desktopWrapperOrigin${WrapperPaths.documents}'
+          'frame_stats.json',
+        ),
+        body: jsonEncode({
+          'frames': sample.length,
+          'p50_ms': percentile(0.50),
+          'p95_ms': percentile(0.95),
+          'max_ms': sample.last,
+          'fps_at_p50': 1000 / percentile(0.50),
+          'fps_at_p95': 1000 / percentile(0.95),
+        }),
+      ),
+    );
+  });
+}
+
+// coverage:ignore-end

app/linux/.gitignore

@@ -1 +0,0 @@
-flutter/ephemeral

app/linux/CMakeLists.txt

@@ -1,128 +0,0 @@
-# Project-level configuration.
-cmake_minimum_required(VERSION 3.13)
-project(runner LANGUAGES CXX)
-
-# The name of the executable created for the application. Change this to change
-# the on-disk name of your application.
-set(BINARY_NAME "diet_guard_app")
-# The unique GTK application identifier for this application. See:
-# https://wiki.gnome.org/HowDoI/ChooseApplicationID
-set(APPLICATION_ID "com.kuhy.diet_guard_app")
-
-# Explicitly opt in to modern CMake behaviors to avoid warnings with recent
-# versions of CMake.
-cmake_policy(SET CMP0063 NEW)
-
-# Load bundled libraries from the lib/ directory relative to the binary.
-set(CMAKE_INSTALL_RPATH "$ORIGIN/lib")
-
-# Root filesystem for cross-building.
-if(FLUTTER_TARGET_PLATFORM_SYSROOT)
-  set(CMAKE_SYSROOT ${FLUTTER_TARGET_PLATFORM_SYSROOT})
-  set(CMAKE_FIND_ROOT_PATH ${CMAKE_SYSROOT})
-  set(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM NEVER)
-  set(CMAKE_FIND_ROOT_PATH_MODE_PACKAGE ONLY)
-  set(CMAKE_FIND_ROOT_PATH_MODE_LIBRARY ONLY)
-  set(CMAKE_FIND_ROOT_PATH_MODE_INCLUDE ONLY)
-endif()
-
-# Define build configuration options.
-if(NOT CMAKE_BUILD_TYPE AND NOT CMAKE_CONFIGURATION_TYPES)
-  set(CMAKE_BUILD_TYPE "Debug" CACHE
-    STRING "Flutter build mode" FORCE)
-  set_property(CACHE CMAKE_BUILD_TYPE PROPERTY STRINGS
-    "Debug" "Profile" "Release")
-endif()
-
-# Compilation settings that should be applied to most targets.
-#
-# Be cautious about adding new options here, as plugins use this function by
-# default. In most cases, you should add new options to specific targets instead
-# of modifying this function.
-function(APPLY_STANDARD_SETTINGS TARGET)
-  target_compile_features(${TARGET} PUBLIC cxx_std_14)
-  target_compile_options(${TARGET} PRIVATE -Wall -Werror)
-  target_compile_options(${TARGET} PRIVATE "$<$<NOT:$<CONFIG:Debug>>:-O3>")
-  target_compile_definitions(${TARGET} PRIVATE "$<$<NOT:$<CONFIG:Debug>>:NDEBUG>")
-endfunction()
-
-# Flutter library and tool build rules.
-set(FLUTTER_MANAGED_DIR "${CMAKE_CURRENT_SOURCE_DIR}/flutter")
-add_subdirectory(${FLUTTER_MANAGED_DIR})
-
-# System-level dependencies.
-find_package(PkgConfig REQUIRED)
-pkg_check_modules(GTK REQUIRED IMPORTED_TARGET gtk+-3.0)
-
-# Application build; see runner/CMakeLists.txt.
-add_subdirectory("runner")
-
-# Run the Flutter tool portions of the build. This must not be removed.
-add_dependencies(${BINARY_NAME} flutter_assemble)
-
-# Only the install-generated bundle's copy of the executable will launch
-# correctly, since the resources must in the right relative locations. To avoid
-# people trying to run the unbundled copy, put it in a subdirectory instead of
-# the default top-level location.
-set_target_properties(${BINARY_NAME}
-  PROPERTIES
-  RUNTIME_OUTPUT_DIRECTORY "${CMAKE_BINARY_DIR}/intermediates_do_not_run"
-)
-
-
-# Generated plugin build rules, which manage building the plugins and adding
-# them to the application.
-include(flutter/generated_plugins.cmake)
-
-
-# === Installation ===
-# By default, "installing" just makes a relocatable bundle in the build
-# directory.
-set(BUILD_BUNDLE_DIR "${PROJECT_BINARY_DIR}/bundle")
-if(CMAKE_INSTALL_PREFIX_INITIALIZED_TO_DEFAULT)
-  set(CMAKE_INSTALL_PREFIX "${BUILD_BUNDLE_DIR}" CACHE PATH "..." FORCE)
-endif()
-
-# Start with a clean build bundle directory every time.
-install(CODE "
-  file(REMOVE_RECURSE \"${BUILD_BUNDLE_DIR}/\")
-  " COMPONENT Runtime)
-
-set(INSTALL_BUNDLE_DATA_DIR "${CMAKE_INSTALL_PREFIX}/data")
-set(INSTALL_BUNDLE_LIB_DIR "${CMAKE_INSTALL_PREFIX}/lib")
-
-install(TARGETS ${BINARY_NAME} RUNTIME DESTINATION "${CMAKE_INSTALL_PREFIX}"
-  COMPONENT Runtime)
-
-install(FILES "${FLUTTER_ICU_DATA_FILE}" DESTINATION "${INSTALL_BUNDLE_DATA_DIR}"
-  COMPONENT Runtime)
-
-install(FILES "${FLUTTER_LIBRARY}" DESTINATION "${INSTALL_BUNDLE_LIB_DIR}"
-  COMPONENT Runtime)
-
-foreach(bundled_library ${PLUGIN_BUNDLED_LIBRARIES})
-  install(FILES "${bundled_library}"
-    DESTINATION "${INSTALL_BUNDLE_LIB_DIR}"
-    COMPONENT Runtime)
-endforeach(bundled_library)
-
-# Copy the native assets provided by the build.dart from all packages.
-set(NATIVE_ASSETS_DIR "${PROJECT_BUILD_DIR}native_assets/linux/")
-install(DIRECTORY "${NATIVE_ASSETS_DIR}"
-   DESTINATION "${INSTALL_BUNDLE_LIB_DIR}"
-   COMPONENT Runtime)
-
-# Fully re-copy the assets directory on each build to avoid having stale files
-# from a previous install.
-set(FLUTTER_ASSET_DIR_NAME "flutter_assets")
-install(CODE "
-  file(REMOVE_RECURSE \"${INSTALL_BUNDLE_DATA_DIR}/${FLUTTER_ASSET_DIR_NAME}\")
-  " COMPONENT Runtime)
-install(DIRECTORY "${PROJECT_BUILD_DIR}/${FLUTTER_ASSET_DIR_NAME}"
-  DESTINATION "${INSTALL_BUNDLE_DATA_DIR}" COMPONENT Runtime)
-
-# Install the AOT library on non-Debug builds only.
-if(NOT CMAKE_BUILD_TYPE MATCHES "Debug")
-  install(FILES "${AOT_LIBRARY}" DESTINATION "${INSTALL_BUNDLE_LIB_DIR}"
-    COMPONENT Runtime)
-endif()

app/linux/flutter/CMakeLists.txt

@@ -1,88 +0,0 @@
-# This file controls Flutter-level build steps. It should not be edited.
-cmake_minimum_required(VERSION 3.10)
-
-set(EPHEMERAL_DIR "${CMAKE_CURRENT_SOURCE_DIR}/ephemeral")
-
-# Configuration provided via flutter tool.
-include(${EPHEMERAL_DIR}/generated_config.cmake)
-
-# TODO: Move the rest of this into files in ephemeral. See
-# https://github.com/flutter/flutter/issues/57146.
-
-# Serves the same purpose as list(TRANSFORM ... PREPEND ...),
-# which isn't available in 3.10.
-function(list_prepend LIST_NAME PREFIX)
-    set(NEW_LIST "")
-    foreach(element ${${LIST_NAME}})
-        list(APPEND NEW_LIST "${PREFIX}${element}")
-    endforeach(element)
-    set(${LIST_NAME} "${NEW_LIST}" PARENT_SCOPE)
-endfunction()
-
-# === Flutter Library ===
-# System-level dependencies.
-find_package(PkgConfig REQUIRED)
-pkg_check_modules(GTK REQUIRED IMPORTED_TARGET gtk+-3.0)
-pkg_check_modules(GLIB REQUIRED IMPORTED_TARGET glib-2.0)
-pkg_check_modules(GIO REQUIRED IMPORTED_TARGET gio-2.0)
-
-set(FLUTTER_LIBRARY "${EPHEMERAL_DIR}/libflutter_linux_gtk.so")
-
-# Published to parent scope for install step.
-set(FLUTTER_LIBRARY ${FLUTTER_LIBRARY} PARENT_SCOPE)
-set(FLUTTER_ICU_DATA_FILE "${EPHEMERAL_DIR}/icudtl.dat" PARENT_SCOPE)
-set(PROJECT_BUILD_DIR "${PROJECT_DIR}/build/" PARENT_SCOPE)
-set(AOT_LIBRARY "${PROJECT_DIR}/build/lib/libapp.so" PARENT_SCOPE)
-
-list(APPEND FLUTTER_LIBRARY_HEADERS
-  "fl_basic_message_channel.h"
-  "fl_binary_codec.h"
-  "fl_binary_messenger.h"
-  "fl_dart_project.h"
-  "fl_engine.h"
-  "fl_json_message_codec.h"
-  "fl_json_method_codec.h"
-  "fl_message_codec.h"
-  "fl_method_call.h"
-  "fl_method_channel.h"
-  "fl_method_codec.h"
-  "fl_method_response.h"
-  "fl_plugin_registrar.h"
-  "fl_plugin_registry.h"
-  "fl_standard_message_codec.h"
-  "fl_standard_method_codec.h"
-  "fl_string_codec.h"
-  "fl_value.h"
-  "fl_view.h"
-  "flutter_linux.h"
-)
-list_prepend(FLUTTER_LIBRARY_HEADERS "${EPHEMERAL_DIR}/flutter_linux/")
-add_library(flutter INTERFACE)
-target_include_directories(flutter INTERFACE
-  "${EPHEMERAL_DIR}"
-)
-target_link_libraries(flutter INTERFACE "${FLUTTER_LIBRARY}")
-target_link_libraries(flutter INTERFACE
-  PkgConfig::GTK
-  PkgConfig::GLIB
-  PkgConfig::GIO
-)
-add_dependencies(flutter flutter_assemble)
-
-# === Flutter tool backend ===
-# _phony_ is a non-existent file to force this command to run every time,
-# since currently there's no way to get a full input/output list from the
-# flutter tool.
-add_custom_command(
-  OUTPUT ${FLUTTER_LIBRARY} ${FLUTTER_LIBRARY_HEADERS}
-    ${CMAKE_CURRENT_BINARY_DIR}/_phony_
-  COMMAND ${CMAKE_COMMAND} -E env
-    ${FLUTTER_TOOL_ENVIRONMENT}
-    "${FLUTTER_ROOT}/packages/flutter_tools/bin/tool_backend.sh"
-      ${FLUTTER_TARGET_PLATFORM} ${CMAKE_BUILD_TYPE}
-  VERBATIM
-)
-add_custom_target(flutter_assemble DEPENDS
-  "${FLUTTER_LIBRARY}"
-  ${FLUTTER_LIBRARY_HEADERS}
-)

app/linux/flutter/generated_plugin_registrant.cc

@@ -1,23 +0,0 @@
-//
-//  Generated file. Do not edit.
-//
-
-// clang-format off
-
-#include "generated_plugin_registrant.h"
-
-#include <file_selector_linux/file_selector_plugin.h>
-#include <flutter_secure_storage_linux/flutter_secure_storage_linux_plugin.h>
-#include <url_launcher_linux/url_launcher_plugin.h>
-
-void fl_register_plugins(FlPluginRegistry* registry) {
-  g_autoptr(FlPluginRegistrar) file_selector_linux_registrar =
-      fl_plugin_registry_get_registrar_for_plugin(registry, "FileSelectorPlugin");
-  file_selector_plugin_register_with_registrar(file_selector_linux_registrar);
-  g_autoptr(FlPluginRegistrar) flutter_secure_storage_linux_registrar =
-      fl_plugin_registry_get_registrar_for_plugin(registry, "FlutterSecureStorageLinuxPlugin");
-  flutter_secure_storage_linux_plugin_register_with_registrar(flutter_secure_storage_linux_registrar);
-  g_autoptr(FlPluginRegistrar) url_launcher_linux_registrar =
-      fl_plugin_registry_get_registrar_for_plugin(registry, "UrlLauncherPlugin");
-  url_launcher_plugin_register_with_registrar(url_launcher_linux_registrar);
-}

app/linux/flutter/generated_plugin_registrant.h

@@ -1,15 +0,0 @@
-//
-//  Generated file. Do not edit.
-//
-
-// clang-format off
-
-#ifndef GENERATED_PLUGIN_REGISTRANT_
-#define GENERATED_PLUGIN_REGISTRANT_
-
-#include <flutter_linux/flutter_linux.h>
-
-// Registers Flutter plugins.
-void fl_register_plugins(FlPluginRegistry* registry);
-
-#endif  // GENERATED_PLUGIN_REGISTRANT_

app/linux/flutter/generated_plugins.cmake

@@ -1,27 +0,0 @@
-#
-# Generated file, do not edit.
-#
-
-list(APPEND FLUTTER_PLUGIN_LIST
-  file_selector_linux
-  flutter_secure_storage_linux
-  url_launcher_linux
-)
-
-list(APPEND FLUTTER_FFI_PLUGIN_LIST
-  jni
-)
-
-set(PLUGIN_BUNDLED_LIBRARIES)
-
-foreach(plugin ${FLUTTER_PLUGIN_LIST})
-  add_subdirectory(flutter/ephemeral/.plugin_symlinks/${plugin}/linux plugins/${plugin})
-  target_link_libraries(${BINARY_NAME} PRIVATE ${plugin}_plugin)
-  list(APPEND PLUGIN_BUNDLED_LIBRARIES $<TARGET_FILE:${plugin}_plugin>)
-  list(APPEND PLUGIN_BUNDLED_LIBRARIES ${${plugin}_bundled_libraries})
-endforeach(plugin)
-
-foreach(ffi_plugin ${FLUTTER_FFI_PLUGIN_LIST})
-  add_subdirectory(flutter/ephemeral/.plugin_symlinks/${ffi_plugin}/linux plugins/${ffi_plugin})
-  list(APPEND PLUGIN_BUNDLED_LIBRARIES ${${ffi_plugin}_bundled_libraries})
-endforeach(ffi_plugin)

app/linux/runner/CMakeLists.txt

@@ -1,26 +0,0 @@
-cmake_minimum_required(VERSION 3.13)
-project(runner LANGUAGES CXX)
-
-# Define the application target. To change its name, change BINARY_NAME in the
-# top-level CMakeLists.txt, not the value here, or `flutter run` will no longer
-# work.
-#
-# Any new source files that you add to the application should be added here.
-add_executable(${BINARY_NAME}
-  "main.cc"
-  "my_application.cc"
-  "${FLUTTER_MANAGED_DIR}/generated_plugin_registrant.cc"
-)
-
-# Apply the standard set of build settings. This can be removed for applications
-# that need different build settings.
-apply_standard_settings(${BINARY_NAME})
-
-# Add preprocessor definitions for the application ID.
-add_definitions(-DAPPLICATION_ID="${APPLICATION_ID}")
-
-# Add dependency libraries. Add any application-specific dependencies here.
-target_link_libraries(${BINARY_NAME} PRIVATE flutter)
-target_link_libraries(${BINARY_NAME} PRIVATE PkgConfig::GTK)
-
-target_include_directories(${BINARY_NAME} PRIVATE "${CMAKE_SOURCE_DIR}")

app/linux/runner/main.cc

@@ -1,6 +0,0 @@
-#include "my_application.h"
-
-int main(int argc, char** argv) {
-  g_autoptr(MyApplication) app = my_application_new();
-  return g_application_run(G_APPLICATION(app), argc, argv);
-}

app/linux/runner/my_application.cc

@@ -1,153 +0,0 @@
-#include "my_application.h"
-
-#include <flutter_linux/flutter_linux.h>
-#ifdef GDK_WINDOWING_X11
-#include <gdk/gdkx.h>
-#endif
-
-#include "flutter/generated_plugin_registrant.h"
-
-struct _MyApplication {
-  GtkApplication parent_instance;
-  char** dart_entrypoint_arguments;
-};
-
-G_DEFINE_TYPE(MyApplication, my_application, GTK_TYPE_APPLICATION)
-
-// Called when first Flutter frame received.
-static void first_frame_cb(MyApplication* self, FlView* view) {
-  gtk_widget_show(gtk_widget_get_toplevel(GTK_WIDGET(view)));
-}
-
-// Implements GApplication::activate.
-static void my_application_activate(GApplication* application) {
-  MyApplication* self = MY_APPLICATION(application);
-  GtkWindow* window =
-      GTK_WINDOW(gtk_application_window_new(GTK_APPLICATION(application)));
-
-  // Use a header bar when running in GNOME as this is the common style used
-  // by applications and is the setup most users will be using (e.g. Ubuntu
-  // desktop).
-  // If running on X and not using GNOME then just use a traditional title bar
-  // in case the window manager does more exotic layout, e.g. tiling.
-  // If running on Wayland assume the header bar will work (may need changing
-  // if future cases occur).
-  gboolean use_header_bar = TRUE;
-#ifdef GDK_WINDOWING_X11
-  GdkScreen* screen = gtk_window_get_screen(window);
-  if (GDK_IS_X11_SCREEN(screen)) {
-    const gchar* wm_name = gdk_x11_screen_get_window_manager_name(screen);
-    if (g_strcmp0(wm_name, "GNOME Shell") != 0) {
-      use_header_bar = FALSE;
-    }
-  }
-#endif
-  if (use_header_bar) {
-    GtkHeaderBar* header_bar = GTK_HEADER_BAR(gtk_header_bar_new());
-    gtk_widget_show(GTK_WIDGET(header_bar));
-    gtk_header_bar_set_title(header_bar, "diet_guard_app");
-    gtk_header_bar_set_show_close_button(header_bar, TRUE);
-    gtk_window_set_titlebar(window, GTK_WIDGET(header_bar));
-  } else {
-    gtk_window_set_title(window, "diet_guard_app");
-  }
-
-  gtk_window_set_default_size(window, 1280, 720);
-
-  // Resolved from the hicolor icon theme, which linux/install_desktop_entry.sh
-  // populates from linux/icons/. Without this the GTK runner shows a generic
-  // placeholder in the taskbar, since Flutter never sets a window icon itself.
-  gtk_window_set_icon_name(window, "diet-guard-app");
-
-  g_autoptr(FlDartProject) project = fl_dart_project_new();
-  fl_dart_project_set_dart_entrypoint_arguments(
-      project, self->dart_entrypoint_arguments);
-
-  FlView* view = fl_view_new(project);
-  GdkRGBA background_color;
-  // Background defaults to black, override it here if necessary, e.g. #00000000
-  // for transparent.
-  gdk_rgba_parse(&background_color, "#000000");
-  fl_view_set_background_color(view, &background_color);
-  gtk_widget_show(GTK_WIDGET(view));
-  gtk_container_add(GTK_CONTAINER(window), GTK_WIDGET(view));
-
-  // Show the window when Flutter renders.
-  // Requires the view to be realized so we can start rendering.
-  g_signal_connect_swapped(view, "first-frame", G_CALLBACK(first_frame_cb),
-                           self);
-  gtk_widget_realize(GTK_WIDGET(view));
-
-  fl_register_plugins(FL_PLUGIN_REGISTRY(view));
-
-  gtk_widget_grab_focus(GTK_WIDGET(view));
-}
-
-// Implements GApplication::local_command_line.
-static gboolean my_application_local_command_line(GApplication* application,
-                                                  gchar*** arguments,
-                                                  int* exit_status) {
-  MyApplication* self = MY_APPLICATION(application);
-  // Strip out the first argument as it is the binary name.
-  self->dart_entrypoint_arguments = g_strdupv(*arguments + 1);
-
-  g_autoptr(GError) error = nullptr;
-  if (!g_application_register(application, nullptr, &error)) {
-    g_warning("Failed to register: %s", error->message);
-    *exit_status = 1;
-    return TRUE;
-  }
-
-  g_application_activate(application);
-  *exit_status = 0;
-
-  return TRUE;
-}
-
-// Implements GApplication::startup.
-static void my_application_startup(GApplication* application) {
-  // MyApplication* self = MY_APPLICATION(object);
-
-  // Perform any actions required at application startup.
-
-  G_APPLICATION_CLASS(my_application_parent_class)->startup(application);
-}
-
-// Implements GApplication::shutdown.
-static void my_application_shutdown(GApplication* application) {
-  // MyApplication* self = MY_APPLICATION(object);
-
-  // Perform any actions required at application shutdown.
-
-  G_APPLICATION_CLASS(my_application_parent_class)->shutdown(application);
-}
-
-// Implements GObject::dispose.
-static void my_application_dispose(GObject* object) {
-  MyApplication* self = MY_APPLICATION(object);
-  g_clear_pointer(&self->dart_entrypoint_arguments, g_strfreev);
-  G_OBJECT_CLASS(my_application_parent_class)->dispose(object);
-}
-
-static void my_application_class_init(MyApplicationClass* klass) {
-  G_APPLICATION_CLASS(klass)->activate = my_application_activate;
-  G_APPLICATION_CLASS(klass)->local_command_line =
-      my_application_local_command_line;
-  G_APPLICATION_CLASS(klass)->startup = my_application_startup;
-  G_APPLICATION_CLASS(klass)->shutdown = my_application_shutdown;
-  G_OBJECT_CLASS(klass)->dispose = my_application_dispose;
-}
-
-static void my_application_init(MyApplication* self) {}
-
-MyApplication* my_application_new() {
-  // Set the program name to the application ID, which helps various systems
-  // like GTK and desktop environments map this running application to its
-  // corresponding .desktop file. This ensures better integration by allowing
-  // the application to be recognized beyond its binary name.
-  g_set_prgname(APPLICATION_ID);
-
-  return MY_APPLICATION(g_object_new(my_application_get_type(),
-                                     "application-id", APPLICATION_ID, "flags",
-                                     G_APPLICATION_NON_UNIQUE, nullptr));
-}

app/linux/runner/my_application.h

@@ -1,21 +0,0 @@
-#ifndef FLUTTER_MY_APPLICATION_H_
-#define FLUTTER_MY_APPLICATION_H_
-
-#include <gtk/gtk.h>
-
-G_DECLARE_FINAL_TYPE(MyApplication,
-                     my_application,
-                     MY,
-                     APPLICATION,
-                     GtkApplication)
-
-/**
- * my_application_new:
- *
- * Creates a new Flutter-based application.
- *
- * Returns: a new #MyApplication.
- */
-MyApplication* my_application_new();
-
-#endif  // FLUTTER_MY_APPLICATION_H_

app/run.sh

@@ -0,0 +1,31 @@
+#!/bin/bash
+# Builds the web bundle and launches the diet_guard companion app through the
+# desktop wrapper, straight out of the repo (no packaging step).
+#
+# The desktop app is a Flutter *web* build rather than a Linux embedder build:
+# the embedder manages only ~20fps at 4K, while the same Dart code in Chrome
+# sustains ~144fps.
+
+set -euo pipefail
+
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+readonly SCRIPT_DIR
+
+log() { echo "==> $*"; }
+
+command -v flutter >/dev/null 2>&1 || {
+    echo "flutter is not on PATH" >&2
+    exit 1
+}
+
+cd "$SCRIPT_DIR"
+flutter config --enable-web >/dev/null
+
+log "fetching pub packages"
+flutter pub get
+
+log "building the web bundle"
+flutter build web --release
+
+log "launching the app"
+exec dart run bin/diet_guard_desktop.dart --web-root "$SCRIPT_DIR/build/web"