From 2b582cf98ddc04266e9172e193cca134bf40e53a Mon Sep 17 00:00:00 2001
From: Friedrich Wilken <jens.wilken@sap.com>
Date: Fri, 12 Jan 2024 14:08:46 +0100
Subject: [PATCH] add script to get version number from a git branch

---
 hack/scripts/get-version-from-branch.sh | 39 +++++++++++++++++++++++++
 1 file changed, 39 insertions(+)
 create mode 100644 hack/scripts/get-version-from-branch.sh

diff --git a/hack/scripts/get-version-from-branch.sh b/hack/scripts/get-version-from-branch.sh
new file mode 100644
index 0000000..0fd4e17
--- /dev/null
+++ b/hack/scripts/get-version-from-branch.sh
@@ -0,0 +1,39 @@
+#!/usr/bin/env bash
+
+# This script will generate the version.
+#
+# First it verifies, that the current branch name is 'release-x.y',
+# where x and y are multi-digit integers.
+# It further looks into the existing tags, looking for ones that start with x.y.
+# If there is none, it will return x.y.0. Otherwise it will return x.y.z where z
+# is the highest existing value increase by one.
+
+# Get the current branch name.
+current_branch=$(git rev-parse --abbrev-ref HEAD)
+
+# Check if the current branch is a release branch.
+if [[ $current_branch =~ ^release-([0-9]+)\.([0-9]+)$ ]]; then
+	# Extract x and y from the branch name. BASH_REMATCH is an array variable
+	# automatically generated by pattern matching ([[ ... ]]).
+	x=${BASH_REMATCH[1]}
+	y=${BASH_REMATCH[2]}
+
+	# Find the highest z value for the matching tags.
+	highest_z=$(git tag -l "$x.$y.*" | cut -d '.' -f 3 | sort -n | tail -n 1)
+
+	# Increment the highest z value by 1 or set to 0 if no matching tags are found.
+	if [ -z "$highest_z" ]; then
+		next_z=0
+	else
+		next_z=$((highest_z + 1))
+	fi
+
+	# Return the new version.
+	new_version="${x}.${y}.${next_z}"
+	echo "${new_version}"
+	export NEW_VERSION=$new_version
+	exit 0
+else
+	echo "Not on a release branch."
+	exit 1
+fi