feat(version): introduce version check subcommand

The version subcommand handles pkgver related commands, the first
subcommand being `check`. Check runs nvchecker if a `.nvchecker.toml`
file exists and compares the current pkgver with the latest release.

Introduces nvchecker as optional dependency which has to be installed in
order to use this particular subcommand.

BREAKING CHANGE: formerly pkgctl version would output the version of the
pkgctl tool, now it is used as a version related subcommand.

Fixes #140

Component: pkgctl version
Component: pkgctl version check
Co-authored-by: Christian Heusel <christian@heusel.eu>

1 files changed, 56 insertions, 0 deletions

diff --git a/src/lib/version.sh b/src/lib/version.sh
new file mode 100644
index 0000000..826b306
--- /dev/null
+++ b/src/lib/version.sh
@@ -0,0 +1,56 @@
+#!/hint/bash
+#
+# SPDX-License-Identifier: GPL-3.0-or-later
+
+[[ -z ${DEVTOOLS_INCLUDE_VERSION_SH:-} ]] || return 0
+DEVTOOLS_INCLUDE_VERSION_SH=1
+
+_DEVTOOLS_LIBRARY_DIR=${_DEVTOOLS_LIBRARY_DIR:-@pkgdatadir@}
+
+set -e
+
+
+pkgctl_version_usage() {
+	local -r COMMAND=${_DEVTOOLS_COMMAND:-${BASH_SOURCE[0]##*/}}
+    cat <<- _EOF_
+		Usage: ${COMMAND} [COMMAND] [OPTIONS]
+
+		Package version related commands.
+
+		COMMANDS
+		    check    Check if there is a newer version availble
+
+		OPTIONS
+		    -h, --help    Show this help text
+
+		EXAMPLES
+		    $ ${COMMAND} check libfoo linux libbar
+_EOF_
+}
+
+pkgctl_version() {
+	if (( $# < 1 )); then
+		pkgctl_version_usage
+		exit 0
+	fi
+
+	while (( $# )); do
+		case $1 in
+			-h|--help)
+				pkgctl_version_usage
+				exit 0
+				;;
+			check)
+				_DEVTOOLS_COMMAND+=" $1"
+				shift
+				# shellcheck source=src/lib/version/check.sh
+				source "${_DEVTOOLS_LIBRARY_DIR}"/lib/version/check.sh
+				pkgctl_version_check "$@"
+				exit 0
+				;;
+			*)
+				die "invalid argument: %s" "$1"
+				;;
+		esac
+	done
+}