install.sh

#!/usr/bin/env bash
#
# mackbind install script
#
# Does the following, in order:
#   1. Build and install the binary to ~/.local/bin/mackbind
#   2. Install the udev rule that opens up /dev/uinput (to create a virtual
#      keyboard) and tags the virtual keyboard as internal, so libinput's
#      "disable touchpad while typing" keeps working while mackbind grabs
#      the physical keyboard
#   3. Add the current user to the input group (to read the physical keyboard)
#   4. Install and enable the GNOME Shell extension that reports the focused window
#      (GNOME only; without it all per-app rules silently degrade), and opt out of
#      GNOME's extension version check so a Shell upgrade cannot silently unload it
#   5. Install and enable the systemd user service
#
# Usage:
#   ./install.sh                 full run
#   ./install.sh --no-build      skip the build, use the existing target/release/mackbind
#   ./install.sh --no-udev       do not install the udev rule (e.g. /dev/uinput is already writable)
#   ./install.sh --no-group      do not modify the input group
#   ./install.sh --no-extension  do not install the GNOME Shell extension
#   ./install.sh --no-service    do not install the systemd user service
#   ./install.sh -h | --help     show help
#
# Uninstall: ./uninstall.sh
#
# Steps that need root (udev / input group) use sudo and may prompt for your password.

set -euo pipefail

# ── Paths ───────────────────────────────────────────────────────────────
REPO_DIR="$(cd -- "$(dirname -- "${BASH_SOURCE[0]}")" && pwd)"
BIN_SRC="$REPO_DIR/target/release/mackbind"
BIN_DST="$HOME/.local/bin/mackbind"
UNIT_DIR="$HOME/.config/systemd/user"
UNIT="$UNIT_DIR/mackbind.service"
UDEV_SRC="$REPO_DIR/packaging/99-mackbind.rules"
UDEV_DST="/etc/udev/rules.d/99-mackbind.rules"

# The GNOME Shell extension that reports the focused window. It is what makes
# the per-app rules (terminal specialization, ptyxis Ctrl+Insert, …) possible;
# see src/focus.rs for the D-Bus interface and why an extension is needed.
EXT_UUID="focused-window-dbus@flexagoon.com"
EXT_DIR="$HOME/.local/share/gnome-shell/extensions/$EXT_UUID"

# ── Arguments ───────────────────────────────────────────────────────────
DO_BUILD=1
DO_UDEV=1
DO_GROUP=1
DO_EXT=1
DO_SERVICE=1

usage() {
  cat <<'USAGE'
mackbind install script

Usage: ./install.sh [options]

Options:
  --no-build      skip the build, use the existing target/release/mackbind
  --no-udev       do not install the udev rule (e.g. /dev/uinput is already writable)
  --no-group      do not modify the input group
  --no-extension  do not install the GNOME Shell extension
  --no-service    do not install the systemd user service
  -h, --help      show this help

Steps that need root (udev / input group) use sudo and may prompt for your password.
To uninstall, use ./uninstall.sh
USAGE
}

for arg in "$@"; do
  case "$arg" in
    --no-build)     DO_BUILD=0 ;;
    --no-udev)      DO_UDEV=0 ;;
    --no-group)     DO_GROUP=0 ;;
    --no-extension) DO_EXT=0 ;;
    --no-service)   DO_SERVICE=0 ;;
    -h|--help)      usage; exit 0 ;;
    *)              printf 'Unknown argument: %s (use --help for usage)\n' "$arg" >&2; exit 2 ;;
  esac
done

# ── Output ──────────────────────────────────────────────────────────────
if [ -t 1 ] && [ -z "${NO_COLOR:-}" ]; then
  C_OK=$'\033[32m'; C_WARN=$'\033[33m'; C_ERR=$'\033[31m'; C_DIM=$'\033[2m'; C_RST=$'\033[0m'
else
  C_OK=; C_WARN=; C_ERR=; C_DIM=; C_RST=
fi
info() { printf '%s==>%s %s\n' "$C_OK" "$C_RST" "$*"; }
warn() { printf '%s[!]%s %s\n' "$C_WARN" "$C_RST" "$*" >&2; }
err()  { printf '%s[x]%s %s\n' "$C_ERR" "$C_RST" "$*" >&2; }
dim()  { printf '%s    %s%s\n' "$C_DIM" "$*" "$C_RST"; }
die()  { err "$*"; exit 1; }

# root or sudo
as_root() {
  if [ "$(id -u)" -eq 0 ]; then "$@"; else sudo "$@"; fi
}

ME="$(id -un)"

# ── Pre-flight checks ───────────────────────────────────────────────────
[ -f "$REPO_DIR/Cargo.toml" ] || die "Not at the repository root (cannot find $REPO_DIR/Cargo.toml)"
[ -f "$UDEV_SRC" ] || die "Missing udev rule file: $UDEV_SRC"

if [ "$DO_UDEV" -eq 1 ] || [ "$DO_GROUP" -eq 1 ]; then
  if [ "$(id -u)" -ne 0 ]; then
    command -v sudo >/dev/null 2>&1 || die "Root permissions are required but sudo is not available"
    info "The next few steps need root permissions and may prompt for your password"
    sudo -v || die "Could not obtain sudo permissions"
  fi
fi

# ── 1. Build ────────────────────────────────────────────────────────────
if [ "$DO_BUILD" -eq 1 ]; then
  command -v cargo >/dev/null 2>&1 \
    || die "cargo not found. Install the Rust toolchain first, or use --no-build to point at an existing binary."
  info "Building the release version…"
  ( cd "$REPO_DIR" && cargo build --release )
elif [ ! -x "$BIN_SRC" ]; then
  die "--no-build was given but no executable was found: $BIN_SRC"
fi
[ -x "$BIN_SRC" ] || die "Build artifact does not exist or is not executable: $BIN_SRC"

# ── 2. Install the binary (stop the service first, or you get "text file busy") ──
SERVICE_WAS_RUNNING=0
if systemctl --user is-active --quiet mackbind 2>/dev/null; then
  SERVICE_WAS_RUNNING=1
  info "A mackbind service is already running; stopping it to replace the binary"
  systemctl --user stop mackbind || true
fi

info "Installing binary → $BIN_DST"
install -Dm755 "$BIN_SRC" "$BIN_DST"
# Verifying is mandatory: twice the user ended up testing an old binary
cmp -s "$BIN_SRC" "$BIN_DST" || die "Installed binary differs from the build artifact (MD5 check failed)"
dim "MD5 $(md5sum "$BIN_DST" | awk '{print $1}') (matches the build artifact)"

# Stopping the service was a means to replace the binary, not a requested
# outcome. With --no-service nothing later starts it again, and the keyboard is
# left silently un-mapped — which looks exactly like "the mapping is broken" —
# so put it back the way we found it.
if [ "$SERVICE_WAS_RUNNING" -eq 1 ] && [ "$DO_SERVICE" -eq 0 ]; then
  info "Restarting the service that was stopped to replace the binary"
  systemctl --user start mackbind \
    || warn "Could not restart the service; run: systemctl --user start mackbind"
fi

# ── 3. input group ──────────────────────────────────────────────────────
NEED_RELOGIN=0
if [ "$DO_GROUP" -eq 1 ]; then
  if id -nG "$ME" | tr ' ' '\n' | grep -qx input; then
    info "$ME is already in the input group, skipping"
  else
    info "Adding $ME to the input group (to read the physical keyboard /dev/input/event*)"
    as_root usermod -aG input "$ME"
    NEED_RELOGIN=1
  fi
fi

# ── 4. udev rule ────────────────────────────────────────────────────────
if [ "$DO_UDEV" -eq 1 ]; then
  if [ -f "$UDEV_DST" ] && cmp -s "$UDEV_SRC" "$UDEV_DST"; then
    info "The udev rule is already up to date, skipping"
  else
    info "Installing udev rule → $UDEV_DST (opening up /dev/uinput)"
    as_root install -m644 "$UDEV_SRC" "$UDEV_DST"
    as_root udevadm control --reload
    as_root udevadm trigger
  fi
fi

# ── 5. GNOME Shell extension (focused window) ───────────────────────────
#
# Every per-app rule has to know which window is focused. Under GNOME Wayland
# that information is not available to clients, so a Shell extension has to
# export it (see src/focus.rs for the interface and the alternatives that were
# measured to be unusable).
#
# Without the extension `focused_wm_class()` returns None, so every app-scoped
# rule silently never matches. In a terminal that turns Cmd+C into the generic
# Cmd+C → Ctrl+C — i.e. SIGINT instead of copy — with no error message anywhere.
# That is why this is a real install step and not just a README footnote.
#
# Only GNOME needs it; on other desktops this is skipped. A newly installed
# extension is loaded by the Shell only when the Shell starts, hence the
# re-login hint at the end (the input-group step needs one anyway).

# True for a GNOME session: the desktop variables are the cheap check, the
# Shell's own bus name the reliable one (they are unset in a TTY or over SSH).
is_gnome_session() {
  case "${XDG_CURRENT_DESKTOP:-}${DESKTOP_SESSION:-}" in
    *GNOME*|*gnome*) return 0 ;;
  esac
  command -v gdbus >/dev/null 2>&1 \
    && gdbus introspect --session --dest org.gnome.Shell --object-path /org/gnome/Shell >/dev/null 2>&1
}

extension_working() {
  command -v gdbus >/dev/null 2>&1 \
    && gdbus call --session --dest org.gnome.Shell \
         --object-path /org/gnome/shell/extensions/FocusedWindow \
         --method org.gnome.shell.extensions.FocusedWindow.Get >/dev/null 2>&1
}

# `gnome-extensions enable` only works once the *running* Shell knows the
# extension; a freshly installed one stays invisible until the Shell restarts,
# because Wayland cannot reload the extension list. Fall back to writing the
# enabled list directly, which the next Shell start picks up.
enable_extension() {
  local uuid="$1" cur
  if gnome-extensions enable "$uuid" >/dev/null 2>&1; then
    dim "Enabled $uuid"
    return 0
  fi
  cur="$(gsettings get org.gnome.shell enabled-extensions 2>/dev/null || true)"
  case "$cur" in
    *"'$uuid'"*) dim "$uuid is already in the enabled list" ;;
    "@as []"|"[]"|"") gsettings set org.gnome.shell enabled-extensions "['$uuid']" 2>/dev/null \
                        || warn "Could not update the enabled list; enable $uuid by hand" ;;
    *) gsettings set org.gnome.shell enabled-extensions "${cur%]}, '$uuid']" 2>/dev/null \
         || warn "Could not update the enabled list; enable $uuid by hand" ;;
  esac
  return 0
}

# GNOME refuses to load an extension whose metadata does not declare the
# running Shell version, and the failure is silent: the extension stays
# "enabled" but is not loaded, so every per-app rule quietly stops matching.
# That is exactly how a system reinstall + Shell upgrade (49/50 → 51) broke
# Cmd+C copy in terminals. Extensions usually keep working across Shell
# upgrades — this one only uses stable Meta/Shell APIs — and release bundles
# on extensions.gnome.org lag behind new Shell versions, so opt out of the
# version check. Measured on GNOME 51: the key exists, Eval/unsafe-mode is
# gone, and this is the only lever against the version churn.
relax_extension_version_check() {
  is_gnome_session || return 0
  command -v gsettings >/dev/null 2>&1 || return 0
  [ "$(gsettings get org.gnome.shell disable-extension-version-validation 2>/dev/null)" = "true" ] \
    && return 0
  if gsettings set org.gnome.shell disable-extension-version-validation true 2>/dev/null; then
    dim "Disabled GNOME extension version validation (keeps $EXT_UUID working across Shell upgrades)"
  else
    warn "Could not disable extension version validation; a Shell upgrade may silently disable $EXT_UUID"
  fi
}

EXT_INSTALLED=0
if [ "$DO_EXT" -eq 1 ]; then
  relax_extension_version_check
fi
if [ "$DO_EXT" -eq 0 ]; then
  dim "--no-extension was given, skipping the GNOME Shell extension"
elif ! is_gnome_session; then
  dim "Not a GNOME session, skipping $EXT_UUID (per-app rules stay inactive)"
elif extension_working; then
  info "The GNOME Shell extension $EXT_UUID is already active, skipping"
elif [ -d "$EXT_DIR" ]; then
  info "$EXT_UUID is installed but not active yet"
  enable_extension "$EXT_UUID"
  EXT_INSTALLED=1
elif ! command -v curl >/dev/null 2>&1; then
  warn "curl not found; skipping $EXT_UUID (per-app rules will stay inactive)"
elif ! command -v gnome-shell >/dev/null 2>&1; then
  warn "gnome-shell not found; skipping $EXT_UUID"
else
  # Resolve the release that matches this Shell version rather than hardcoding
  # one: extensions.gnome.org picks the newest bundle whose metadata declares
  # this Shell in `shell-version`.
  SHELL_MAJOR="$(gnome-shell --version 2>/dev/null | sed -E 's/[^0-9]*([0-9]+).*/\1/')"
  info "Installing the GNOME Shell extension $EXT_UUID (for Shell $SHELL_MAJOR)"
  BUNDLE_URL="$(curl -fsSL \
    "https://extensions.gnome.org/extension-info/?uuid=$EXT_UUID&shell_version=$SHELL_MAJOR" 2>/dev/null \
    | sed -n 's/.*"download_url": *"\([^"]*\)".*/\1/p')"
  if [ -z "$BUNDLE_URL" ]; then
    warn "No $EXT_UUID release found for Shell $SHELL_MAJOR (offline, or unsupported)"
    dim "Per-app rules will stay inactive; see README.md for the manual steps"
  else
    EXT_TMP="$(mktemp -d)"
    if curl -fsSL -o "$EXT_TMP/ext.zip" "https://extensions.gnome.org$BUNDLE_URL" 2>/dev/null \
       && gnome-extensions install --force "$EXT_TMP/ext.zip"; then
      enable_extension "$EXT_UUID"
      EXT_INSTALLED=1
    else
      warn "Failed to download or install $EXT_UUID (per-app rules will stay inactive)"
    fi
    rm -rf "$EXT_TMP"
  fi
fi

if [ "$EXT_INSTALLED" -eq 1 ] && extension_working; then
  info "The focused-window extension is live ✅"
fi

# ── 6. systemd user service ─────────────────────────────────────────────
if [ "$DO_SERVICE" -eq 1 ]; then
  info "Installing systemd user service → $UNIT"
  mkdir -p "$UNIT_DIR"
  cat > "$UNIT" <<'EOF'
[Unit]
Description=mackbind — macOS keybindings for Linux
After=graphical-session.target

[Service]
Type=simple
ExecStart=%h/.local/bin/mackbind
Restart=on-failure
RestartSec=2

[Install]
WantedBy=default.target
EOF
  systemctl --user daemon-reload
  systemctl --user enable mackbind >/dev/null
  systemctl --user reset-failed mackbind 2>/dev/null || true
fi

# ── 7. Start right away if permissions are ready, otherwise suggest re-login ──
keyboard_readable() {
  for d in /dev/input/event*; do
    [ -r "$d" ] && return 0
  done
  return 1
}

STARTED=0
if [ "$DO_SERVICE" -eq 1 ]; then
  if keyboard_readable && [ -w /dev/uinput ]; then
    info "Permissions are ready, starting the service"
    systemctl --user restart mackbind
    sleep 1
    if systemctl --user is-active --quiet mackbind; then
      info "mackbind is running ✅"
      STARTED=1
    else
      warn "The service failed to start; check the log: journalctl --user -u mackbind -n 30 --no-pager"
    fi
  else
    NEED_RELOGIN=1
  fi
fi

# ── Wrap-up ─────────────────────────────────────────────────────────────
echo
if [ "$NEED_RELOGIN" -eq 1 ] || [ "$EXT_INSTALLED" -eq 1 ]; then
  warn "One step left: log out and back in (or reboot) so the changes take effect:"
  [ "$NEED_RELOGIN" -eq 1 ] && dim "- input group membership applies to your processes only in a new session"
  [ "$EXT_INSTALLED" -eq 1 ] && dim "- a newly installed GNOME Shell extension is loaded only when the Shell starts"
  [ "$DO_SERVICE" -eq 1 ] && dim "The service is enabled and will start automatically after you log back in."
  dim "Self-check after re-login: ls -l /dev/uinput    # should be root input 0660"
  dim "             systemctl --user status mackbind"
  dim "             gdbus call --session --dest org.gnome.Shell \\"
  dim "               --object-path /org/gnome/shell/extensions/FocusedWindow \\"
  dim "               --method org.gnome.shell.extensions.FocusedWindow.Get"
elif [ "$STARTED" -eq 0 ]; then
  info "Done (service not enabled; run mackbind yourself as needed)."
else
  info "Done."
fi