Add some logging and fix the version script when git describe doesn't…

… get any matches.

utils/build/gen_version.py

@@ -3,36 +3,61 @@
 import os
 import subprocess
 import sys
+import logging
+
+# Configure logging to output to stderr
+logging.basicConfig(level=logging.INFO, stream=sys.stderr)
+
+def parse_version(version_str):
+    try:
+        version_parts = version_str.split('-')
+        if len(version_parts) >= 2:
+            version = version_parts[0] + '-' + version_parts[1].replace('.', '.') + '+' + '.'.join(version_parts[2:]).replace('-', '+').replace('.dirty', '+dirty')
+        else:
+            version = version_str
+        return version
+    except Exception as e:
+        logging.error(f"Error parsing version string: {e}")
+        return ''
 
 def get_version(source_root):
     version_file = os.path.join(source_root, 'dat', 'VERSION')
+    version = ""
+
     if os.path.isdir(os.path.join(source_root, '.git')):
         # In the git repo. Build the tag from git info
         try:
             git_describe = subprocess.run(['git', '-C', source_root, 'describe', '--tags', '--match', 'v*', '--dirty'], capture_output=True, text=True)
             git_output = git_describe.stdout.strip()
-            version_parts = git_output[1:].split('-')
-            version = version_parts[0] + '-' + version_parts[1].replace('.', '.') + '+' + '.'.join(version_parts[2:]).replace('-', '+').replace('.dirty', '+dirty')
+            version = parse_version(git_output[1:])
             with open(version_file, 'w') as f:
                 f.write(version)
         except subprocess.CalledProcessError:
-            version = ''
-    elif os.path.isfile(version_file):
+            pass
+
+    if not version and os.path.isfile(version_file):
         # In a source package. Version file should exist.
         with open(version_file, 'r') as f:
             version = f.read().strip()
-    else:
+
+    if not version:
         # Couldn't find git repo or a packaged VERSION file
+        # Did you clone the repo with --depth=1?
         # Did you download the zip'd repo instead of a release?
-        version = f"{sys.argv[1]}+dev"
+        if len(sys.argv) > 1:
+            version = f"{sys.argv[1]}+dev"
+        else:
+            version = "0.0.0+dev"
         with open(version_file, 'w') as f:
             f.write(version)
+
     return version
 
 if __name__ == "__main__":
     source_root = os.getenv('MESON_SOURCE_ROOT')
     if source_root:
         version = get_version(source_root)
+        logging.info(f"Version retrieved: {version}")
         print(version)
     else:
-        print("Error: MESON_SOURCE_ROOT environment variable not set.")
+        logging.error("Error: MESON_SOURCE_ROOT environment variable not set.")