Update import nethack logfile script

- Add a few roles to the ROLES mapping
- Check if the logfile changed before writing it (avoid updating the timestamp
  if no changes were made)

scripts/import-nethack-logfile.py

@@ -45,11 +45,14 @@ RACES = {
 }
 
 ROLES = {
+    'Arc': 'Archaeologist',
+    'Kni': 'Knight',
     'Mon': 'Monk',
     'Pri': 'Priest',
     'Ran': 'Ranger',
     'Rog': 'Rogue',
     'Sam': 'Samurai',
+    'Val': 'Valkyrie',
 }
 
 GENDERS = {
@@ -64,7 +67,7 @@ ALIGNMENTS = {
 
 def parse_args(argv, *a, **kw):
     parser = argparse.ArgumentParser(*a, **kw)
-    parser.add_argument('-o', '--output',help='Path to the output file')
+    parser.add_argument('-o', '--output', help='Path to the output file')
     parser.add_argument('logfile', help='Path to the Nethack log file to convert')
     args = parser.parse_args(argv)
     return args
@@ -133,15 +136,26 @@ def main(argv):
         'logfile': records,
     }
 
+    logfile_has_changed = False
     output_path = args.output
+    output_file = None
+
     if output_path and output_path != '-':
-        output_file = open(output_path, 'w')
+        with open(output_path, 'r') as existing_logfile:
+            existing_logfile_object = json.load(existing_logfile)
+            logfile_has_changed = existing_logfile_object.get('logfile', {}) != records 
+
+        if logfile_has_changed:
+            output_file = open(output_path, 'w')
     else:
         output_file = sys.stdout
 
-    json.dump(output_object, output_file, indent=2)
-    output_file.write('\n')
-    output_file.close()
+    if output_file:
+        json.dump(output_object, output_file, indent=2)
+        output_file.write('\n')
+        output_file.close()
+    else:
+        print('No changes to logfile')
 
     return 0