socktop-swipe/install.sh

#!/bin/sh
# socktop-swipe installer.
#
#   curl -fsSL https://gt.wittyoneoff.com/jason/socktop-swipe/raw/branch/main/install.sh | sh
#
# or, from a checkout:
#
#   ./install.sh
#
# Everything is checked BEFORE anything is installed, and the full cost is
# printed once. Nothing touches the system before you answer the summary.
#
#   --yes         accept every default without asking
#   --uninstall   hand over to uninstall.sh
#   --prefix DIR  install to DIR/bin instead of /usr/local/bin
set -eu

REPO=https://gt.wittyoneoff.com/jason/socktop-swipe
PREFIX=/usr/local
ASSUME_YES=no
SRC=""

for a in "$@"; do
	case "$a" in
	--yes | -y) ASSUME_YES=yes ;;
	--prefix=*) PREFIX=${a#--prefix=} ;;
	--uninstall) exec sh -c "$(dirname "$0")/uninstall.sh" ;;
	-h | --help) sed -n '2,16p' "$0" | sed 's/^# \{0,1\}//'; exit 0 ;;
	*) echo "unknown option: $a" >&2; exit 2 ;;
	esac
done

BIN="$PREFIX/bin"
CONF_DIR="$HOME/.config/socktop-swipe"
CONF="$CONF_DIR/config.yaml"
UDEV=/etc/udev/rules.d/70-socktop-swipe.rules
XBLANK=/etc/X11/xorg.conf.d/10-no-blanking-socktop-swipe.conf
LIGHTDM=/etc/lightdm/lightdm.conf.d/50-autologin-socktop-swipe.conf

# --------------------------------------------------------------------------
# Asking
# --------------------------------------------------------------------------
# Piping into sh leaves stdin holding the SCRIPT, not a keyboard, so prompts
# must read the terminal directly. With no terminal at all we take defaults and
# say so rather than silently guessing.
if [ -r /dev/tty ] && [ -t 1 ]; then HAVE_TTY=yes; else HAVE_TTY=no; fi

say() { printf '%s\n' "$*"; }
step() { printf '\n==> %s\n' "$*"; }
warn() { printf '  !! %s\n' "$*" >&2; }

# ask "question" default(y|n) -> 0 for yes
ask() {
	_q=$1
	_d=$2
	if [ "$ASSUME_YES" = yes ] || [ "$HAVE_TTY" = no ]; then
		[ "$_d" = y ] && return 0 || return 1
	fi
	[ "$_d" = y ] && _hint="[Y/n]" || _hint="[y/N]"
	while :; do
		printf '  %s %s ' "$_q" "$_hint" >/dev/tty
		read -r _a </dev/tty || _a=""
		[ -z "$_a" ] && _a=$_d
		case "$_a" in
		[Yy] | [Yy][Ee][Ss]) return 0 ;;
		[Nn] | [Nn][Oo]) return 1 ;;
		esac
	done
}

# askval "question" "default" -> echoes the answer
askval() {
	if [ "$ASSUME_YES" = yes ] || [ "$HAVE_TTY" = no ]; then
		printf '%s' "$2"
		return
	fi
	printf '  %s [%s] ' "$1" "$2" >/dev/tty
	read -r _a </dev/tty || _a=""
	[ -z "$_a" ] && _a=$2
	printf '%s' "$_a"
}

have() { command -v "$1" >/dev/null 2>&1; }

# --------------------------------------------------------------------------
# Preflight
# --------------------------------------------------------------------------
say "socktop-swipe installer"
say "======================="

OS_NAME=$(. /etc/os-release 2>/dev/null && printf '%s' "${PRETTY_NAME:-unknown}" || true)
[ -n "$OS_NAME" ] || OS_NAME=unknown
ARCH=$(uname -m)

PKG=""
PKG_INSTALL=""
for p in apt-get dnf pacman zypper apk; do
	if have $p; then
		PKG=$p
		break
	fi
done
case "$PKG" in
apt-get) PKG_INSTALL="sudo apt-get install -y" ;;
dnf) PKG_INSTALL="sudo dnf install -y" ;;
pacman) PKG_INSTALL="sudo pacman -S --needed --noconfirm" ;;
zypper) PKG_INSTALL="sudo zypper install -y" ;;
apk) PKG_INSTALL="sudo apk add" ;;
esac

# Display manager and window manager, for the autostart and autologin steps.
# NB: written as `if`, not `[ x ] && y`. Under `set -e` an AND-OR list that
# ends up false aborts the script, so a box with no lightdm would exit here.
DM=none
if [ -d /etc/lightdm ]; then DM=lightdm
elif [ -d /etc/gdm3 ] || [ -d /etc/gdm ]; then DM=gdm
elif [ -f /etc/sddm.conf ] || [ -d /etc/sddm.conf.d ]; then DM=sddm
fi

WM=none
if have i3; then WM=i3; fi

TERMINAL=""
for t in alacritty foot kitty xterm; do
	if have $t; then
		TERMINAL=$t
		break
	fi
done

LOCKER=""
for l in xss-lock light-locker xscreensaver gnome-screensaver; do
	if have $l; then
		LOCKER="$LOCKER $l"
	fi
done

# Space for the toolchain and the build. Both land under $HOME unless
# CARGO_HOME says otherwise, which is exactly the 8GB-of-eMMC case.
avail_mb() { df -Pm "$1" 2>/dev/null | awk 'NR==2 {print $4}'; }
HOME_FREE=$(avail_mb "$HOME")
PREFIX_FREE=$(avail_mb "$(dirname "$PREFIX")")

step "Found"
say "  system         $OS_NAME ($ARCH)"
say "  packages       ${PKG:-none detected}"
say "  display mgr    $DM"
say "  window mgr     $WM"
say "  terminal       ${TERMINAL:-none found}"
say "  tmux           $(tmux -V 2>/dev/null || echo 'NOT INSTALLED')"
# Not `cargo --version | cut ... || echo`: the pipeline's status is cut's, and
# cut succeeds on empty input, so the fallback would never fire.
if have cargo; then
	say "  cargo          $(cargo --version 2>/dev/null | cut -d' ' -f1-2)"
else
	say "  cargo          NOT INSTALLED"
fi
say "  git            $(git --version 2>/dev/null || echo 'NOT INSTALLED')"
say "  free space     ${HOME_FREE:-?} MB in \$HOME, ${PREFIX_FREE:-?} MB on $PREFIX"
if [ -n "$LOCKER" ]; then say "  screen locker $LOCKER"; fi

# What we are about to need.
NEED_PKGS=""
NEED_RUSTUP=no
COST_MB=10

if ! have tmux; then NEED_PKGS="$NEED_PKGS tmux"; fi
if ! have git; then NEED_PKGS="$NEED_PKGS git"; fi
if ! have cargo; then
	NEED_RUSTUP=yes
	COST_MB=$((COST_MB + 1200))
fi
# The build itself. Measured on an Atom x5-Z8350: a 103 MB target directory,
# 108 seconds, peaking at 1.1 GB of RAM. 250 leaves headroom.
COST_MB=$((COST_MB + 250))

if [ -z "$TERMINAL" ]; then
	warn "no terminal emulator found. socktop-swipe can attach in an existing"
	warn "terminal, but unattended autostart needs one. alacritty is the tested choice."
fi
if [ -z "$PKG" ]; then
	warn "no supported package manager. Nothing will be installed for you;"
	warn "make sure tmux, git and a Rust toolchain are present."
fi
if [ -n "$HOME_FREE" ] && [ "$HOME_FREE" -lt "$COST_MB" ]; then
	warn "only ${HOME_FREE} MB free in \$HOME but about ${COST_MB} MB is needed."
	warn "A source build will not fit. Free space first, or set CARGO_HOME and"
	warn "CARGO_TARGET_DIR to somewhere with room."
fi

step "This will"
if [ -n "$NEED_PKGS" ]; then say "  install packages:$NEED_PKGS"; fi
if [ "$NEED_RUSTUP" = yes ]; then say "  install the Rust toolchain via rustup (~1.2 GB)"; fi
say "  build socktop-swipe from source (~100 MB of build artifacts)"
say "  install the binary to $BIN"
say "  write a starter config to $CONF"
say "  ...then ask about the touch device, autostart, autologin and blanking."
say ""
say "  About ${COST_MB} MB of disk. Nothing has been changed yet."
say ""

if [ "$HAVE_TTY" = no ]; then
	say "No terminal available, so every question takes its default."
	say "Run the script directly for the interactive version:"
	say "  curl -fsSLO $REPO/raw/branch/main/install.sh && sh install.sh"
	say ""
fi

ask "Continue?" y || { say "Nothing done."; exit 0; }

# --------------------------------------------------------------------------
# Dependencies
# --------------------------------------------------------------------------
if [ -n "$NEED_PKGS" ]; then
	step "Installing:$NEED_PKGS"
	if [ -z "$PKG_INSTALL" ]; then
		warn "no package manager -- install$NEED_PKGS yourself and re-run."
		exit 1
	fi
	if [ "$PKG" = apt-get ]; then sudo apt-get update; fi
	# shellcheck disable=SC2086
	$PKG_INSTALL $NEED_PKGS
fi

if [ "$NEED_RUSTUP" = yes ]; then
	step "Installing the Rust toolchain"
	if ask "Install rustup now?" y; then
		curl -fsSL https://sh.rustup.rs | sh -s -- -y --profile minimal --no-modify-path
		# shellcheck disable=SC1091
		. "$HOME/.cargo/env"
	else
		say "Install Rust yourself, then re-run this script."
		exit 1
	fi
fi
if ! have cargo; then warn "cargo still not on PATH -- open a new shell and re-run."; exit 1; fi

# --------------------------------------------------------------------------
# Source
# --------------------------------------------------------------------------
here=$(CDPATH='' cd -- "$(dirname -- "$0")" 2>/dev/null && pwd || echo "")
if [ -n "$here" ] && [ -f "$here/Cargo.toml" ]; then
	SRC=$here
	step "Building from this checkout: $SRC"
else
	SRC="$HOME/.local/src/socktop-swipe"
	step "Fetching the source to $SRC"
	mkdir -p "$(dirname "$SRC")"
	if [ -d "$SRC/.git" ]; then
		git -C "$SRC" pull --ff-only
	else
		git clone "$REPO" "$SRC"
	fi
fi

step "Building (this is the slow part on a low-power box)"
( cd "$SRC" && cargo build --release )
sudo install -d "$BIN"
sudo install -m 755 "$SRC/target/release/socktop-swipe" "$BIN/socktop-swipe"
say "  installed $BIN/socktop-swipe"

# --------------------------------------------------------------------------
# Touch device
# --------------------------------------------------------------------------
step "Touch panel"
DEVICE=""
# Prefer the by-id path: eventN numbers get reshuffled on reboot.
for d in /dev/input/by-id/*event*; do
	[ -e "$d" ] || continue
	if udevadm info --query=property --name="$d" 2>/dev/null | grep -q '^ID_INPUT_TOUCHSCREEN=1'; then
		say "  found touchscreen: $d"
		if [ -z "$DEVICE" ]; then DEVICE=$d; fi
	fi
done
if [ -z "$DEVICE" ]; then
	warn "no touchscreen found under /dev/input/by-id/."
	warn "If the panel is not plugged in yet, that is fine -- set touch.device"
	warn "in the config later. 'socktop-swipe doctor --list' will show it."
	DEVICE=/dev/input/by-id/CHANGE-ME
else
	DEVICE=$(askval "Use which device?" "$DEVICE")
fi

step "Device access"
say "  Reading touch events needs permission on the device."
say "  A udev rule grants it for touchscreens only and takes effect at once."
say "  The 'input' group grants access to every input device, keyboard included,"
say "  and needs a full logout."
RELOGIN=no
if ask "Install the udev rule?" y; then
	sudo install -m 644 "$SRC/packaging/70-socktop-swipe.rules" "$UDEV"
	sudo udevadm control --reload
	sudo udevadm trigger --subsystem-match=input
	say "  wrote $UDEV"
	if ! id -nG | tr ' ' '\n' | grep -qx input; then
		warn "the rule uses GROUP=input and you are not in it."
		if ask "Add $(id -un) to the 'input' group as well?" y; then
			sudo usermod -aG input "$(id -un)"
			RELOGIN=yes
		fi
	fi
elif ask "Add $(id -un) to the 'input' group instead?" n; then
	sudo usermod -aG input "$(id -un)"
	RELOGIN=yes
fi

# --------------------------------------------------------------------------
# Config
# --------------------------------------------------------------------------
step "Configuration"
mkdir -p "$CONF_DIR"
if [ -e "$CONF" ]; then
	say "  keeping the existing $CONF"
else
	sed "s|^  device: .*|  device: $DEVICE|" "$SRC/config.example.yaml" >"$CONF"
	say "  wrote $CONF"
	say "  EDIT IT: the example screens are the author's rack, not yours."
fi

# --------------------------------------------------------------------------
# Optional monitors
# --------------------------------------------------------------------------
step "Monitor programs (all optional -- socktop-swipe runs whatever you configure)"
if ! have socktop && ask "Install socktop (the point of the project)?" y; then
	cargo install socktop
fi
if ! have uptime-kuma-status && ask "Install uptime-kuma-status?" n; then
	cargo install uptime-kuma-status
fi
if ! have unifly && ask "Build unifly (UniFi TUI) from source?" n; then
	U="$HOME/.local/src/unifly"
	mkdir -p "$(dirname "$U")"
	if [ -d "$U/.git" ]; then git -C "$U" pull --ff-only; else
		git clone https://github.com/jasonwitty/unifly "$U"
	fi
	( cd "$U" && cargo build --profile release-small -p unifly )
	say "  built $U/target/release-small/unifly"
	say "  put that path under 'binaries: unifly:' in $CONF"
fi

# --------------------------------------------------------------------------
# Unattended operation
# --------------------------------------------------------------------------
step "Wall-display behaviour"

if ask "Stop the screen blanking, sleeping and locking?" y; then
	sudo mkdir -p /etc/X11/xorg.conf.d
	sudo tee "$XBLANK" >/dev/null <<-'EOF'
	# Installed by socktop-swipe. This is a wall display: it must never blank.
	Section "ServerFlags"
	    Option "BlankTime"   "0"
	    Option "StandbyTime" "0"
	    Option "SuspendTime" "0"
	    Option "OffTime"     "0"
	EndSection
	EOF
	say "  wrote $XBLANK"
	# The Xorg snippet covers every session including the greeter and survives
	# reboots; xset covers a session that re-enables blanking after X starts.
	# Both are needed, and xset MUST run as the session user -- under sudo it
	# targets root's X connection and silently does nothing.
	if [ -n "${DISPLAY:-}" ] && have xset; then
		xset s off s noblank -dpms 2>/dev/null || true
		say "  applied to the running session"
	fi
	for l in $LOCKER; do
		warn "$l is installed and may still lock the screen. Disable it in your"
		warn "session's autostart."
	done
fi

if [ "$WM" = i3 ] && [ -e "$HOME/.config/i3/config" ]; then
	if ask "Add the i3 autostart lines?" y; then
		i3conf="$HOME/.config/i3/config"
		if grep -q socktop-swipe "$i3conf"; then
			say "  already present; leaving it alone"
		else
			bak="$i3conf.bak-$(date +%Y%m%d-%H%M%S)"
			cp "$i3conf" "$bak"
			{
				printf '\n# --- socktop-swipe ---\n'
				printf '# One process: builds the session, opens it in a terminal and reads the panel.\n'
				printf 'exec --no-startup-id %s/socktop-swipe run\n' "$BIN"
				printf '# Never blank (the Xorg snippet covers reboots; this covers this session).\n'
				printf 'exec --no-startup-id xset s off s noblank -dpms\n'
				if have unclutter; then
					printf '# With the panel grabbed, nothing ever moves the pointer, so hide it.\n'
					printf 'exec --no-startup-id unclutter --timeout 1 --ignore-scrolling\n'
				fi
			} >>"$i3conf"
			if i3 -C -c "$i3conf" >/dev/null 2>&1; then
				say "  added the autostart (backup: $bak)"
			else
				cp "$bak" "$i3conf"
				warn "i3 rejected the config; restored $bak"
			fi
		fi
	fi
elif [ "$DM" != none ] || [ "$WM" != none ]; then
	say "  no i3 config found. For a systemd user session instead:"
	say "    cp $SRC/packaging/socktop-swipe.service ~/.config/systemd/user/"
	say "    systemctl --user enable --now socktop-swipe"
fi

if [ "$DM" = lightdm ]; then
	say ""
	say "  Autologin makes the display come back by itself after a power cut."
	say "  ANYONE WITH PHYSICAL ACCESS TO THE PANEL GETS THIS USER'S SESSION."
	say "  Only do this where the account is nothing but the dashboard."
	if ask "Log $(id -un) straight into $WM at boot?" n; then
		sudo mkdir -p /etc/lightdm/lightdm.conf.d
		sudo tee "$LIGHTDM" >/dev/null <<-EOF
		# Installed by socktop-swipe. Delete this file to restore the login prompt.
		[Seat:*]
		autologin-user=$(id -un)
		autologin-user-timeout=0
		autologin-session=$WM
		EOF
		say "  wrote $LIGHTDM (takes effect at next boot)"
	fi
elif [ "$DM" != none ]; then
	say "  Autologin is only automated for lightdm; yours is $DM. Configure it there"
	say "  if the display must come back unattended after a power cut."
fi

# --------------------------------------------------------------------------
say ""
say "=============================================================="
say "Installed."
if [ "$RELOGIN" = yes ]; then say "LOG OUT AND BACK IN before use (group membership changed)."; fi
cat <<EOF

Next:
  1. Edit $CONF -- the screens are the author's, not yours.
  2. socktop-swipe validate    check it, and see the grid map
  3. socktop-swipe doctor      swipe, and see what the panel reports
  4. socktop-swipe run         build the session and start swiping

EOF
say "=============================================================="