chore: break down into functions

ansible/files/postgres_prestart.sh.j2

@@ -1,9 +1,49 @@
 #!/bin/bash
 
+check_orioledb_enabled() {
+   local pg_conf="/etc/postgresql/postgresql.conf"
+   if [ ! -f "$pg_conf" ]; then
+       return 0
+    fi
+   grep "^shared_preload_libraries" "$pg_conf" | grep -c "orioledb" || return 0
+}
+
+get_shared_buffers() {
+    local opt_conf="/etc/postgresql-custom/generated-optimizations.conf"
+    if [ ! -f "$opt_conf" ]; then
+        return 0
+    fi
+    grep "^shared_buffers = " "$opt_conf" | cut -d "=" -f2 | tr -d ' ' || return 0
+}
+
+update_orioledb_buffers() {
+   local pg_conf="/etc/postgresql/postgresql.conf"
+   local value="$1"
+   if grep -q "^orioledb.main_buffers = " "$pg_conf"; then
+       sed -i "s/^orioledb.main_buffers = .*/orioledb.main_buffers = $value/" "$pg_conf"
+   else
+       echo "orioledb.main_buffers = $value" >> "$pg_conf"
+   fi
+}
+
+main() {
+   local has_orioledb=$(check_orioledb_enabled)
+   if [ "$has_orioledb" -lt 1 ]; then
+       return 0
+   fi
+   local shared_buffers_value=$(get_shared_buffers)
+   if [ ! -z "$shared_buffers_value" ]; then
+       update_orioledb_buffers "$shared_buffers_value"
+   fi
+}
+
+# Initial locale setup
 if [ $(cat /etc/locale.gen | grep -c en_US.UTF-8) -eq 0 ]; then
-    echo "en_US.UTF-8 UTF-8" >> /etc/locale.gen
+   echo "en_US.UTF-8 UTF-8" >> /etc/locale.gen
 fi
 
 if [ $(locale -a | grep -c en_US.utf8) -eq 0 ]; then
-    locale-gen
+   locale-gen
 fi
+
+main