Add parse_offsets utility script

app/parse_offsets.py

@@ -0,0 +1,45 @@
+import json
+import logging
+import argparse
+import sys
+
+logger = logging.getLogger("svganim.fixer")
+argParser = argparse.ArgumentParser(
+    description="Helper tool to fix timings after glitch"
+)
+argParser.add_argument(
+    "--input", type=str, help="Filename to run on (.json_appendable)"
+)
+args = argParser.parse_args()
+
+
+with open(args.input, "r") as fp:
+    events = json.loads("[" + fp.read() + "]")
+    time_offset = 0
+    for i, event in enumerate(events):
+        if type(event) is list:
+            pass
+        elif event['event'] == "offset":
+            time_offset += event['offset']
+            # print a reverseable event that is ignored by this script
+            event = {
+                'event': 'added_offset',
+                'offset': event['offset']
+            }
+        elif event['event'] == 'added_offset':
+            logger.warning('ignore existing offset')
+            continue
+
+        elif event["event"] == "viewbox":
+            for key, box in enumerate(event['viewboxes']):
+                event['viewboxes'][key]['t'] += time_offset
+        elif event["event"] == "stroke":
+            event['points'] = [[p[0], p[1], p[2], p[3] + time_offset]
+                               for p in event['points']]
+
+        if i>0:
+            sys.stdout.write(",\n")    
+        sys.stdout.write(json.dumps(event))
+
+if time_offset == 0:
+    logger.warning('\n\nNo offset defined in file, please do so by adding {"event":"offset", "offset": miliseconds} at the line from which the offset should be added.')