From d3e903db3378f3b5f782f8cdfc61c55eef2dd0b8 Mon Sep 17 00:00:00 2001
From: Krzesimir Nowak <knowak@microsoft.com>
Date: Mon, 27 Nov 2023 11:26:43 +0100
Subject: [PATCH 1/3] ci-automation/image-changes: Simplify getting a major
 version

---
 ci-automation/image_changes.sh | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/ci-automation/image_changes.sh b/ci-automation/image_changes.sh
index 372c2d0819..7159f5e89f 100644
--- a/ci-automation/image_changes.sh
+++ b/ci-automation/image_changes.sh
@@ -491,11 +491,11 @@ function get_channel_a_and_version_a() {
     local -n gcaava_version_a_ref="${gcaava_version_a_varname}"
     local major_a major_b channel version
 
-    major_a=$(echo "${new_channel_prev_version}" | cut -d . -f 1)
-    major_b=$(echo "${new_channel_new_version}" | cut -d . -f 1)
+    major_a=${new_channel_prev_version%%.*}
+    major_b=${new_channel_new_version%%.*}
     # When the major version for the new channel is different, a transition has happened and we can find the previous release in the old channel
-    if [ "${major_a}" != "${major_b}" ]; then
-        case "${new_channel}" in
+    if [[ ${major_a} != "${major_b}" ]]; then
+        case ${new_channel} in
           lts)
             channel=stable
             ;;

From 3e8bd5b8ee4625c48c01d6bd22febe585fb96141 Mon Sep 17 00:00:00 2001
From: Krzesimir Nowak <knowak@microsoft.com>
Date: Mon, 27 Nov 2023 11:28:30 +0100
Subject: [PATCH 2/3] ci-automation/image-changes: Factor out curl invocation

---
 ci-automation/image_changes.sh | 15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/ci-automation/image_changes.sh b/ci-automation/image_changes.sh
index 7159f5e89f..d5ffa74752 100644
--- a/ci-automation/image_changes.sh
+++ b/ci-automation/image_changes.sh
@@ -528,6 +528,15 @@ function channel_version() (
     # traps.
     trap 'rm "${tmp_version_txt}"' EXIT
 
+    curl_to_stdout "https://${channel}.release.flatcar-linux.net/${board}/current/version.txt" >"${tmp_version_txt}"
+    source "${tmp_version_txt}"
+    echo "${FLATCAR_VERSION}"
+)
+# --
+
+function curl_to_stdout() {
+    local url=${1}; shift
+
     curl \
         -fsSL \
         --retry-delay 1 \
@@ -535,10 +544,8 @@ function channel_version() (
         --retry-connrefused \
         --retry-max-time 60 \
         --connect-timeout 20 \
-        "https://${channel}.release.flatcar-linux.net/${board}/current/version.txt" >"${tmp_version_txt}"
-    source "${tmp_version_txt}"
-    echo "${FLATCAR_VERSION}"
-)
+        "${url}"
+}
 # --
 
 # Prints some reports using scripts from the passed path to

From 1c2fec4abce62ac6688ee7a15b635c21eddb699a Mon Sep 17 00:00:00 2001
From: Krzesimir Nowak <knowak@microsoft.com>
Date: Mon, 27 Nov 2023 11:28:57 +0100
Subject: [PATCH 3/3] ci-automation/image-changes: Get proper version for LTS
 channel

The refactored image changes script will eventually be run for the old
LTS version, so make sure that the script for that channel will get a
last release of old LTS instead of new LTS.
---
 ci-automation/image_changes.sh | 34 +++++++++++++++++++++++++++++++++-
 1 file changed, 33 insertions(+), 1 deletion(-)

diff --git a/ci-automation/image_changes.sh b/ci-automation/image_changes.sh
index d5ffa74752..6af4be47eb 100644
--- a/ci-automation/image_changes.sh
+++ b/ci-automation/image_changes.sh
@@ -355,7 +355,11 @@ function prepare_env_vars_and_params_for_release() {
     board="${arch}-usr"
 
     new_channel="${ppfr_channel}"
-    new_channel_prev_version=$(channel_version "${new_channel}" "${board}")
+    if [[ ${new_channel} = 'lts' ]]; then
+        new_channel_prev_version=$(lts_channel_version "${ppfr_version_id%%.*}" "${board}")
+    else
+        new_channel_prev_version=$(channel_version "${new_channel}" "${board}")
+    fi
     channel_a=''
     version_a=''
     get_channel_a_and_version_a "${new_channel}" "${new_channel_prev_version}" "${ppfr_version}" "${board}" channel_a version_a
@@ -516,6 +520,34 @@ function get_channel_a_and_version_a() {
 }
 # --
 
+function lts_channel_version() (
+    local major=${1}; shift
+    local board=${1}; shift
+
+    local tmp_lts_info tmp_version_txt
+    tmp_lts_info=$(mktemp)
+    tmp_version_txt=$(mktemp)
+    # This function runs in a subshell, so we can have our own scoped
+    # traps.
+    trap 'rm "${tmp_lts_info}" "${tmp_version_txt}"' EXIT
+    curl_to_stdout 'https://lts.release.flatcar-linux.net/lts-info' >"${tmp_lts_info}"
+    local line tuple lts_major year
+    while read -r line; do
+        # each line is major:year:(supported|unsupported)
+        mapfile -t tuple <<<"${line//:/$'\n'}"
+        lts_major="${tuple[0]}"
+        if [[ ${lts_major} = "${major}" ]]; then
+            year="${tuple[1]}"
+            break
+        fi
+    done <"${tmp_lts_info}"
+
+    curl_to_stdout "https://lts.release.flatcar-linux.net/${board}/current-${year}/version.txt" >"${tmp_version_txt}"
+    source "${tmp_version_txt}"
+    echo "${FLATCAR_VERSION}"
+)
+# --
+
 # Gets the latest release for given channel and board. For lts channel
 # gets a version of the latest LTS. Runs in a subshell.
 function channel_version() (