task: Add timewarrior hook

Added hook starting and stopping timewarrior tracking whenever starting,
stopping or completing a task in taskwarrior.
Really nice script, robust as well for starting multiple tasks and
start/stopping intermittently.

taskwarrior/.local/share/task/hooks/on-modify.timewarrior

@@ -0,0 +1,102 @@
+#!/usr/bin/env python3
+
+###############################################################################
+#
+# Copyright 2016 - 2021, Thomas Lauf, Paul Beckingham, Federico Hernandez.
+#
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included
+# in all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+# OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+# THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+# SOFTWARE.
+#
+# https://www.opensource.org/licenses/mit-license.php
+#
+###############################################################################
+
+from __future__ import print_function
+
+import json
+import subprocess
+import sys
+
+# Hook should extract all of the following for use as Timewarrior tags:
+#   UUID
+#   Project
+#   Tags
+#   Description
+#   UDAs
+
+try:
+    input_stream = sys.stdin.buffer
+except AttributeError:
+    input_stream = sys.stdin
+
+# Make no changes to the task, simply observe.
+old = json.loads(input_stream.readline().decode("utf-8", errors="replace"))
+new = json.loads(input_stream.readline().decode("utf-8", errors="replace"))
+print(json.dumps(new))
+
+
+def extract_tags_from(json_obj):
+    # Extract attributes for use as tags.
+    tags = [json_obj['description']]
+
+    if 'project' in json_obj:
+        tags.append(json_obj['project'])
+
+    if 'tags' in json_obj:
+        tags.extend(json_obj['tags'])
+
+    return tags
+
+
+def extract_annotation_from(json_obj):
+
+    if 'annotations' not in json_obj:
+        return '\'\''
+
+    return json_obj['annotations'][0]['description']
+
+
+start_or_stop = ''
+
+# Started task.
+if 'start' in new and 'start' not in old:
+    start_or_stop = 'start'
+
+# Stopped task.
+elif ('start' not in new or 'end' in new) and 'start' in old:
+    start_or_stop = 'stop'
+
+if start_or_stop:
+    tags = extract_tags_from(new)
+
+    subprocess.call(['timew', start_or_stop] + tags + [':yes'])
+
+# Modifications to task other than start/stop
+elif 'start' in new and 'start' in old:
+    old_tags = extract_tags_from(old)
+    new_tags = extract_tags_from(new)
+
+    if old_tags != new_tags:
+        subprocess.call(['timew', 'untag', '@1'] + old_tags + [':yes'])
+        subprocess.call(['timew', 'tag', '@1'] + new_tags + [':yes'])
+
+    old_annotation = extract_annotation_from(old)
+    new_annotation = extract_annotation_from(new)
+
+    if old_annotation != new_annotation:
+        subprocess.call(['timew', 'annotate', '@1', new_annotation])