feat: Automatic update check with opt out (#9)

Author: MFelida

user/local/share/towel/bin/towel

@@ -14,6 +14,9 @@ if [ ! -d "$TOWEL_BIN_DIR" ]; then
 	exit 1
 fi
 
+# shellcheck source=user/local/share/towel/bin/towel-common
+source "$TOWEL_BIN_DIR/towel-common"
+
 function print_help() {
 	"$TOWEL_BIN_DIR/towel-help"
 }
@@ -39,6 +42,8 @@ function unknown_option() {
 	exit 1
 }
 
+towel_auto_update_check
+
 if [ $# -eq 0 ]; then
 	exec "$TOWEL_BIN_DIR/towel-enter"
 fi

user/local/share/towel/bin/towel-common

@@ -285,4 +285,52 @@ function towel_remove_exported_apps() {
 	[ -d "$export_apps_dir" ] && rm -rf "$export_apps_dir"
 }
 
+function towel_auto_update_check() {
+	[ -n "${CONTAINER_ID:-}" ] && return
+	[ "${TOWEL_NO_UPDATE_CHECK:-}" = "1" ] && return
+	[ -f "$TOWEL_DATA/no-update-check" ] && return
+
+	local today
+	today="$(date +%Y-%m-%d)"
+	local check_state="$TOWEL_DATA/update_check"
+	local notified_file="$TOWEL_DATA/update_notified"
+	local stored_date="" stored_status="" stored_latest=""
+
+	local stored_line
+	if stored_line="$(cat "$check_state" 2>/dev/null)"; then
+		read -r stored_date stored_status stored_latest <<<"$stored_line"
+	fi
+
+	if [ "$stored_date" = "$today" ] && [ "$stored_status" = "lt" ] && [ -n "$stored_latest" ]; then
+		local notified_date
+		notified_date="$(cat "$notified_file" 2>/dev/null || true)"
+		if [ "$notified_date" != "$today" ]; then
+			echo 1>&2 "towel update available: $TOWEL_VERSION -> $stored_latest"
+			echo 1>&2 "  Run 'towel update --apply' to update, or 'towel update --no-auto-check' to disable these notifications."
+			printf '%s\n' "$today" >"$notified_file"
+		fi
+	fi
+
+	if [ "${stored_date:-}" != "$today" ]; then
+		(
+			out="$("$TOWEL_BIN_DIR/towel-update" --check 2>/dev/null)"
+			rc=$?
+			ts="$(date +%Y-%m-%d)"
+			case $rc in
+			0) printf '%s eq\n' "$ts" >"$check_state" ;;
+			10)
+				ver="$(printf '%s\n' "$out" | grep -oE '[0-9]+\.[0-9]+\.[0-9]+$' | tail -1)"
+				if [ -n "$ver" ]; then
+					printf '%s lt %s\n' "$ts" "$ver" >"$check_state"
+				else
+					printf '%s error\n' "$ts" >"$check_state"
+				fi
+				;;
+			*) printf '%s error\n' "$ts" >"$check_state" ;;
+			esac
+		) >/dev/null 2>&1 &
+		disown 2>/dev/null || true
+	fi
+}
+
 _towel_set_opts

user/local/share/towel/bin/towel-update

@@ -14,20 +14,25 @@ TOWEL_GITHUB_REPO="${TOWEL_GITHUB_REPO:-codam-coding-college/towel}"
 
 function print_usage() {
 	echo 1>&2 "Usage:
-  towel update --check  [--quiet]
-  towel update --apply  [-y|--yes]
+  towel update --check           [--quiet]
+  towel update --apply           [-y|--yes]
+  towel update --no-auto-check
+  towel update --auto-check
   towel update [-h|--help]
 
 Flags:
-  --check        Query GitHub for the latest release and compare to the installed version.
-                 Exits 0 if up to date, 10 if an update is available, 1 on error.
-  --apply        Download, verify, and install the latest release.
-  -y, --yes      Skip the confirmation prompt (--apply only).
-  --quiet        Suppress stdout output (--check only; stderr and exit code preserved).
-  -h, --help     Print this help text.
+  --check          Query GitHub for the latest release and compare to the installed version.
+                   Exits 0 if up to date, 10 if an update is available, 1 on error.
+  --apply          Download, verify, and install the latest release.
+  -y, --yes        Skip the confirmation prompt (--apply only).
+  --quiet          Suppress stdout output (--check only; stderr and exit code preserved).
+  --no-auto-check  Disable the automatic daily update check and notifications.
+  --auto-check     Re-enable the automatic daily update check.
+  -h, --help       Print this help text.
 
 Environment:
-  TOWEL_GITHUB_REPO  Override the GitHub owner/repo (default: codam-coding-college/towel)."
+  TOWEL_GITHUB_REPO       Override the GitHub owner/repo (default: codam-coding-college/towel)
+  TOWEL_NO_UPDATE_CHECK   Set to 1 to disable automatic update checks."
 }
 
 function _towel_update_compare() {
@@ -67,6 +72,8 @@ for arg in "$@"; do
 	case "$arg" in
 	--check) mode="check" ;;
 	--apply) mode="apply" ;;
+	--no-auto-check) mode="no-auto-check" ;;
+	--auto-check) mode="auto-check" ;;
 	-y | --yes) assume_yes="true" ;;
 	--quiet) quiet="true" ;;
 	-h | --help)
@@ -82,11 +89,24 @@ for arg in "$@"; do
 done
 
 if [ -z "$mode" ]; then
-	echo 1>&2 "towel update: a mode flag is required (--check or --apply)"
+	echo 1>&2 "towel update: a mode flag is required (--check, --apply, --no-auto-check, or --auto-check)"
 	print_usage
 	exit 64
 fi
 
+if [ "$mode" = "no-auto-check" ]; then
+	touch "$TOWEL_DATA/no-update-check"
+	echo "Automatic update checks disabled."
+	echo "  Re-enable with: towel update --auto-check"
+	exit 0
+fi
+
+if [ "$mode" = "auto-check" ]; then
+	rm -f "$TOWEL_DATA/no-update-check" "$TOWEL_DATA/update_check" "$TOWEL_DATA/update_notified"
+	echo "Automatic update checks enabled."
+	exit 0
+fi
+
 latest_version="$(_towel_fetch_latest_version)" || {
 	echo 1>&2 "towel update --${mode} failed: could not reach GitHub API (check network connectivity)"
 	exit 1