GPT-6.1 Sol (effort default (no reasoning-effort override) · thinking on) on iCalendar recurrence expansion with time-zone transitions, exceptions and overrides

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{"type": "item.completed", "item": {"id": "item_2", "type": "command_execution", "command": "/bin/bash -lc 'cat input.json calendar.ics'", "aggregated_output": "{\n \"ics\": \"calendar.ics\",\n \"timezones\": {\n  \"Test/Central\": {\n   \"initial_offset_min\": 60,\n   \"transitions\": [\n    [\n     \"2026-03-29T01:00:00Z\",\n     120\n    ],\n    [\n     \"2026-10-25T01:00:00Z\",\n     60\n    ],\n    [\n     \"2027-03-28T01:00:00Z\",\n     120\n    ]\n   ]\n  },\n  \"Test/West\": {\n   \"initial_offset_min\": -300,\n   \"transitions\": [\n    [\n     \"2026-03-08T07:00:00Z\",\n     -240\n    ],\n    [\n     \"2026-11-01T06:00:00Z\",\n     -300\n    ]\n   ]\n  }\n },\n \"window_start\": \"2026-02-15T00:00:00Z\",\n \"window_end\": \"2026-12-15T00:00:00Z\"\n}BEGIN:VCALENDAR\r\nVERSION:2.0\r\nPRODID:-//synthetic//EN\r\nBEGIN:VEVENT\r\nUID:[REDACTED:email]\r\nDTSTART:20260621T150000Z\r\nSUMMARY:Zero length mark\r\nEND:VEVENT\r\nBEGIN:VEVENT\r\nUID:[REDACTED:email]\r\nDTSTART;TZID=Test/West:20260305T233000\r\nDURATION:PT1H30M\r\nSUMMARY:Weekly crew briefing\\, dock 2\r\nRRULE:FREQ=WEEKLY;INTERVAL=2;BYDAY=TU,TH,SA;COUNT=23\r\nEXDATE;TZID=Test/West:20260413T233000,20260521T233000\r\nEND:VEVENT\r\nBEGIN:VEVENT\r\nUID:[REDACTED:email]\r\nDTSTART;TZID=Test/West:20260308T023000\r\nDURATION:PT1H\r\nSUMMARY:Gap test\r\nRRULE:FREQ=YEARLY;COUNT=1\r\nEND:VEVENT\r\nBEGIN:VEVENT\r\nUID:[REDACTED:email]\r\nDTSTART:20260130T120000Z\r\nDURATION:PT45M\r\nSUMMARY:Month-end fuel check\r\nRRULE:FREQ=MONTHLY;BYMONTHDAY=31;UNTIL=20261001T000000Z\r\nEND:VEVENT\r\nBEGIN:VEVENT\r\nUID:[REDACTED:email]\r\nRECURRENCE-ID;TZID=Test/West:20260305T233000\r\nDTSTART;TZID=Test/West:20260305T010000\r\nDURATION:PT1H\r\nSUMMARY:Briefing moved\r\nEND:VEVENT\r\nBEGIN:VEVENT\r\nUID:[REDACTED:email]\r\nRECURRENCE-ID;TZID=Test/Central:20261111T070000\r\nDTSTART;TZID=Test/Central:20261111T070000\r\nSTATUS:CANCELLED\r\nSUMMARY:x\r\nEND:VEVENT\r\nBEGIN:VEVENT\r\nUID:[REDACTED:email]\r\nDTSTART;TZID=Test/West:20261101T013000\r\nDURATION:PT1H\r\nSUMMARY:Overlap test\r\nEND:VEVENT\r\nBEGIN:VEVENT\r\nUID:[REDACTED:email]\r\nDTSTART:20250609T090000Z\r\nDURATION:P1D\r\nsummary:Annual survey\r\nRRULE:FREQ=YEARLY;BYMONTH=4,9;BYMONTHDAY=1\r\nEND:VEVENT\r\nBEGIN:VEVENT\r\nUID:[REDACTED:email]\r\nDTSTART;VALUE=DATE:20260304\r\nSUMMARY:Haul-out day (all day)\r\nRRULE:FREQ=WEEKLY;INTERVAL=3;BYDAY=SA;UNTIL=20261115\r\nEXDATE;VALUE=DATE:20260502,20260725\r\nEND:VEVENT\r\nBEGIN:VEVENT\r\nUID:[REDACTED:email]\r\nDTSTART;TZID=\"Test/Central\":20260323T070000\r\nDURATION:PT30M\r\nSUMMARY:Daily weather\\nbriefing\r\nRRULE:FREQ=DAILY;INTERVAL=3;UNTIL=20261031T000000Z\r\nBEGIN:VALARM\r\nTRIGGER:-PT10M\r\nSUMMARY:alarm text\r\nEND:VALARM\r\nRDATE;TZID=Test/Central:20261111T070000,20261201T070000\r\nEND:VEVENT\r\nBEGIN:VEVENT\r\nUID:[REDACTED:email]\r\nDTSTART;TZID=Test/West:20260111T180000\r\nDURATION:PT2H\r\nSUMMARY:Last Friday race night\r\nRRULE:FREQ=MONTHLY;BYDAY=-1FR;COUNT=7\r\nEND:VEVENT\r\nEND:VCALENDAR\r\n", "exit_code": 0, "status": "completed"}}
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{"type": "item.started", "item": {"id": "item_5", "type": "command_execution", "command": "/bin/bash -lc \"cat > solve.py <<'PY'\nimport calendar\nimport datetime as dt\nimport json\nimport re\nimport sys\nfrom pathlib import Path\n\nDAY = dt.timedelta(days=1)\nWEEKDAYS = ['MO', 'TU', 'WE', 'TH', 'FR', 'SA', 'SU']\n\n\ndef instant(s):\n    return dt.datetime.fromisoformat(s.rstrip('Z')).replace(tzinfo=None)\n\n\ndef split_quoted(s, sep):\n    parts, start, quoted = [], 0, False\n    for i, c in enumerate(s):\n        if c == '\\\"':\n            quoted = not quoted\n        elif c == sep and not quoted:\n            parts.append(s[start:i])\n            start = i + 1\n    parts.append(s[start:])\n    return parts\n\n\ndef parse(text):\n    # Also accept fixtures serialized with literal CRLF escape sequences.\n    if '\\\\n' not in text and r'\\\\r\\\\n' in text:\n        text = text.replace(r'\\\\r\\\\n', '\\\\n')\n    lines = []\n    for line in text.splitlines():\n        if not line:\n            continue\n        if line[0] in ' \\\\t' and lines:\n            lines[-1] += line[1:]\n        else:\n            lines.append(line)\n    events, stack, event = [], [], None\n    for line in lines:\n        pieces = split_quoted(line, ':')\n        if len(pieces) < 2:\n            continue\n        head, value = pieces[0], ':'.join(pieces[1:])\n        fields = split_quoted(head, ';')\n        name = fields[0].upper()\n        params = {}\n        for field in fields[1:]:\n            if '=' in field:\n                key, val = field.split('=', 1)\n                params[key.upper()] = val.strip('\\\"')\n        if name == 'BEGIN':\n            stack.append(value.upper())\n            if value.upper() == 'VEVENT' and event is None:\n                event = {}\n                event_depth = len(stack)\n                events.append(event)\n            continue\n        if name == 'END':\n            if event is not None and len(stack) == event_depth:\n                event = None\n            if stack:\n                stack.pop()\n            continue\n        if event is not None and len(stack) == event_depth:\n            if name in ('EXDATE', 'RDATE'):\n                event.setdefault(name, []).append((params, value))\n            elif name not in event:\n                event[name] = (params, value)\n    return events\n\n\nclass Engine:\n    def __init__(self, config):\n        self.zones = {}\n        for name, z in config.get('timezones', {}).items():\n            self.zones[name] = (z['initial_offset_min'], sorted((instant(t), o) for t, o in z['transitions']))\n\n    def utc(self, local, zone):\n        if not zone or zone not in self.zones:\n            return local\n        offset, transitions = self.zones[zone]\n        lower = dt.datetime.min\n        matches = []\n        for upper, new_offset in transitions + [(dt.datetime.max, None)]:\n            candidate = local - dt.timedelta(minutes=offset)\n            if lower <= candidate < upper:\n                matches.append(candidate)\n            if new_offset is not None:\n                before = upper + dt.timedelta(minutes=offset)\n                after = upper + dt.timedelta(minutes=new_offset)\n                if before <= local < after:\n                    gap = local - dt.timedelta(minutes=offset)\n            lower, offset = upper, new_offset\n        if matches:\n            return min(matches)\n        return gap\n\n    def date(self, prop):\n        params, s = prop\n        all_day = params.get('VALUE', '').upper() == 'DATE' or len(s) == 8\n        if all_day:\n            return dt.datetime.strptime(s, '%Y%m%d').date(), None\n        local = dt.datetime.strptime(s.rstrip('Z'), '%Y%m%dT%H%M%S')\n        return local, None if s.endswith('Z') else params.get('TZID')\n\n    def key(self, prop):\n        local, zone = self.date(prop)\n        return self.utc(local, zone) if isinstance(local, dt.datetime) else local\n\n    def length(self, event):\n        start = self.key(event['DTSTART'])\n        if 'DTEND' in event:\n            return self.key(event['DTEND']) - start\n        if 'DURATION' in event:\n            s = event['DURATION'][1]\n            match = re.fullmatch(r'P(?:(\\\\d+)W)?(?:(\\\\d+)D)?(?:T(?:(\\\\d+)H)?(?:(\\\\d+)M)?(?:(\\\\d+)S)?)?', s)\n            w, d, h, m, sec = [int(x or 0) for x in match.groups()]\n            return dt.timedelta(weeks=w, days=d, hours=h, minutes=m, seconds=sec)\n        return dt.timedelta(0) if isinstance(start, dt.datetime) else DAY\n\n\ndef month_days(year, month, rule, default):\n    n = calendar.monthrange(year, month)[1]\n    days = set(range(1, n + 1))\n    if 'BYMONTHDAY' in rule:\n        days &= {v if v > 0 else n + v + 1 for v in map(int, rule['BYMONTHDAY'].split(','))}\n    if 'BYDAY' in rule:\n        selected = set()\n        for token in rule['BYDAY'].split(','):\n            weekday = WEEKDAYS.index(token[-2:])\n            matching = [d for d in range(1, n + 1) if dt.date(year, month, d).weekday() == weekday]\n            if token[:-2]:\n                ordinal = int(token[:-2])\n                index = ordinal - 1 if ordinal > 0 else ordinal\n                if -len(matching) <= index < len(matching):\n                    selected.add(matching[index])\n            else:\n                selected.update(matching)\n        days &= selected\n    if 'BYMONTHDAY' not in rule and 'BYDAY' not in rule:\n        days &= {default}\n    return sorted(days)\n\n\ndef candidates(start, rule, horizon):\n    date = start.date() if isinstance(start, dt.datetime) else start\n    freq = rule['FREQ']\n    interval = int(rule.get('INTERVAL', 1))\n    if interval <= 0:\n        return\n    def wall(d):\n        return dt.datetime.combine(d, start.time()) if isinstance(start, dt.datetime) else d\n    if freq in ('MONTHLY', 'YEARLY'):\n        year, month = date.year, date.month\n        while year <= horizon.year:\n            months = [month] if freq == 'MONTHLY' else sorted(set(map(int, rule.get('BYMONTH', str(date.month)).split(','))))\n            for mo in months:\n                if not 1 <= mo <= 12:\n                    continue\n                if freq == 'MONTHLY' and 'BYMONTH' in rule and mo not in map(int, rule['BYMONTH'].split(',')):\n                    continue\n                for day in month_days(year, mo, rule, date.day):\n                    d = dt.date(year, mo, day)\n                    if date <= d <= horizon:\n                        yield wall(d)\n            if freq == 'YEARLY':\n                year += interval\n            else:\n                total = year * 12 + month - 1 + interval\n                year, mo = divmod(total, 12)\n                month = mo + 1\n                if (year, month) > (horizon.year, horizon.month):\n                    break\n        return\n    d = date\n    week_start = date - dt.timedelta(days=date.weekday())\n    byday = {WEEKDAYS.index(x[-2:]) for x in rule.get('BYDAY', WEEKDAYS[date.weekday()]).split(',')}\n    while d <= horizon:\n        valid = freq == 'DAILY' or ((d - week_start).days // 7 % interval == 0 and d.weekday() in byday)\n        if valid and 'BYMONTH' in rule:\n            valid = d.month in map(int, rule['BYMONTH'].split(','))\n        if valid and 'BYMONTHDAY' in rule:\n            n = calendar.monthrange(d.year, d.month)[1]\n            valid = d.day in {v if v > 0 else n + v + 1 for v in map(int, rule['BYMONTHDAY'].split(','))}\n        if valid and freq == 'DAILY' and 'BYDAY' in rule:\n            valid = d.weekday() in byday\n        if valid:\n            yield wall(d)\n        step = interval if freq == 'DAILY' else 1\n        if (horizon - d).days < step:\n            break\n        d += dt.timedelta(days=step)\n\n\ndef solve(config, base):\n    engine = Engine(config)\n    path = config.get('ics', config.get('calendar', 'calendar.ics'))\n    events = parse((base / path).read_text())\n    ws, we = instant(config['window_start']), instant(config['window_end'])\n    overrides = {}\n    for e in events:\n        if 'RECURRENCE-ID' in e:\n            overrides[(e.get('UID', ({}, ''))[1], engine.key(e['RECURRENCE-ID']))] = e\n    result = []\n    def emit(e, start, override=False):\n        if e.get('STATUS', ({}, ''))[1].upper() == 'CANCELLED':\n            return\n        end = start + engine.length(e)\n        timed = isinstance(start, dt.datetime)\n        lo, hi = (ws, we) if timed else (ws.date(), we.date())\n        if not ((lo <= start < hi) if end == start else (start < hi and end > lo)):\n            return\n        summary = e.get('SUMMARY', ({}, ''))[1]\n        summary = re.sub(r'\\\\\\\\([\\\\\\\\;,nN])', lambda m: '\\\\n' if m[1] in 'nN' else m[1], summary)\n        fmt = lambda x: x.strftime('%Y-%m-%dT%H:%M:%SZ') if timed else x.isoformat()\n        result.append(dict(uid=e.get('UID', ({}, ''))[1], summary=summary, start=fmt(start), end=fmt(end), all_day=not timed, override=override))\n    for event in events:\n        if 'RECURRENCE-ID' in event or 'DTSTART' not in event:\n            continue\n        uid = event.get('UID', ({}, ''))[1]\n        local, zone = engine.date(event['DTSTART'])\n        starts = set()\n        if 'RRULE' in event:\n            rule = dict(part.split('=', 1) for part in event['RRULE'][1].upper().split(';'))\n            horizon = we.date() + dt.timedelta(days=3)\n            for (u, key) in overrides:\n                if u == uid:\n                    horizon = max(horizon, (key.date() if isinstance(key, dt.datetime) else key) + dt.timedelta(days=3))\n            until = None\n            if 'UNTIL' in rule:\n                until = engine.key(({}, rule['UNTIL']))\n                if isinstance(local, dt.datetime) and not isinstance(until, dt.datetime):\n                    until = dt.datetime.combine(until, dt.time(23, 59, 59))\n                elif not isinstance(local, dt.datetime) and isinstance(until, dt.datetime):\n                    until = until.date()\n                horizon = min(horizon, (until.date() if isinstance(until, dt.datetime) else until) + dt.timedelta(days=2))\n            count = 0\n            for candidate in candidates(local, rule, horizon):\n                key = engine.utc(candidate, zone) if isinstance(candidate, dt.datetime) else candidate\n                if until is not None and key > until:\n                    continue\n                count += 1\n                if count > int(rule.get('COUNT', 10**30)):\n                    break\n                starts.add(key)\n        else:\n            starts.add(engine.key(event['DTSTART']))\n        for params, values in event.get('RDATE', []):\n            starts.update(engine.key((params, value)) for value in values.split(','))\n        excluded = set()\n        for params, values in event.get('EXDATE', []):\n            excluded.update(engine.key((params, value)) for value in values.split(','))\n        for start in starts - excluded:\n            override = overrides.get((uid, start))\n            if override is not None:\n                if 'DTSTART' in override:\n                    emit(override, engine.key(override['DTSTART']), True)\n            else:\n                emit(event, start)\n    result.sort(key=lambda o: (o['start'] if not o['all_day'] else o['start'] + 'T00:00:00Z', o['uid']))\n    return dict(occurrences=result, count=len(result), events_parsed=len(events))\n\n\nif __name__ == '__main__':\n    source = Path(sys.argv[1])\n    answer = solve(json.loads(source.read_text()), source.resolve().parent)\n    Path(sys.argv[2]).write_text(json.dumps(answer, indent=2) + '\\\\n')\nPY\npython3 solve.py input.json answer.json\npython3 - <<'PY'\nimport json\nfrom collections import Counter\nx=json.load(open('answer.json'))\nprint(x['count'], x['events_parsed'])\nprint(Counter(o['summary'] for o in x['occurrences']))\nPY\"", "aggregated_output": "", "exit_code": null, "status": "in_progress"}}
{"type": "item.completed", "item": {"id": "item_5", "type": "command_execution", "command": "/bin/bash -lc \"cat > solve.py <<'PY'\nimport calendar\nimport datetime as dt\nimport json\nimport re\nimport sys\nfrom pathlib import Path\n\nDAY = dt.timedelta(days=1)\nWEEKDAYS = ['MO', 'TU', 'WE', 'TH', 'FR', 'SA', 'SU']\n\n\ndef instant(s):\n    return dt.datetime.fromisoformat(s.rstrip('Z')).replace(tzinfo=None)\n\n\ndef split_quoted(s, sep):\n    parts, start, quoted = [], 0, False\n    for i, c in enumerate(s):\n        if c == '\\\"':\n            quoted = not quoted\n        elif c == sep and not quoted:\n            parts.append(s[start:i])\n            start = i + 1\n    parts.append(s[start:])\n    return parts\n\n\ndef parse(text):\n    # Also accept fixtures serialized with literal CRLF escape sequences.\n    if '\\\\n' not in text and r'\\\\r\\\\n' in text:\n        text = text.replace(r'\\\\r\\\\n', '\\\\n')\n    lines = []\n    for line in text.splitlines():\n        if not line:\n            continue\n        if line[0] in ' \\\\t' and lines:\n            lines[-1] += line[1:]\n        else:\n            lines.append(line)\n    events, stack, event = [], [], None\n    for line in lines:\n        pieces = split_quoted(line, ':')\n        if len(pieces) < 2:\n            continue\n        head, value = pieces[0], ':'.join(pieces[1:])\n        fields = split_quoted(head, ';')\n        name = fields[0].upper()\n        params = {}\n        for field in fields[1:]:\n            if '=' in field:\n                key, val = field.split('=', 1)\n                params[key.upper()] = val.strip('\\\"')\n        if name == 'BEGIN':\n            stack.append(value.upper())\n            if value.upper() == 'VEVENT' and event is None:\n                event = {}\n                event_depth = len(stack)\n                events.append(event)\n            continue\n        if name == 'END':\n            if event is not None and len(stack) == event_depth:\n                event = None\n            if stack:\n                stack.pop()\n            continue\n        if event is not None and len(stack) == event_depth:\n            if name in ('EXDATE', 'RDATE'):\n                event.setdefault(name, []).append((params, value))\n            elif name not in event:\n                event[name] = (params, value)\n    return events\n\n\nclass Engine:\n    def __init__(self, config):\n        self.zones = {}\n        for name, z in config.get('timezones', {}).items():\n            self.zones[name] = (z['initial_offset_min'], sorted((instant(t), o) for t, o in z['transitions']))\n\n    def utc(self, local, zone):\n        if not zone or zone not in self.zones:\n            return local\n        offset, transitions = self.zones[zone]\n        lower = dt.datetime.min\n        matches = []\n        for upper, new_offset in transitions + [(dt.datetime.max, None)]:\n            candidate = local - dt.timedelta(minutes=offset)\n            if lower <= candidate < upper:\n                matches.append(candidate)\n            if new_offset is not None:\n                before = upper + dt.timedelta(minutes=offset)\n                after = upper + dt.timedelta(minutes=new_offset)\n                if before <= local < after:\n                    gap = local - dt.timedelta(minutes=offset)\n            lower, offset = upper, new_offset\n        if matches:\n            return min(matches)\n        return gap\n\n    def date(self, prop):\n        params, s = prop\n        all_day = params.get('VALUE', '').upper() == 'DATE' or len(s) == 8\n        if all_day:\n            return dt.datetime.strptime(s, '%Y%m%d').date(), None\n        local = dt.datetime.strptime(s.rstrip('Z'), '%Y%m%dT%H%M%S')\n        return local, None if s.endswith('Z') else params.get('TZID')\n\n    def key(self, prop):\n        local, zone = self.date(prop)\n        return self.utc(local, zone) if isinstance(local, dt.datetime) else local\n\n    def length(self, event):\n        start = self.key(event['DTSTART'])\n        if 'DTEND' in event:\n            return self.key(event['DTEND']) - start\n        if 'DURATION' in event:\n            s = event['DURATION'][1]\n            match = re.fullmatch(r'P(?:(\\\\d+)W)?(?:(\\\\d+)D)?(?:T(?:(\\\\d+)H)?(?:(\\\\d+)M)?(?:(\\\\d+)S)?)?', s)\n            w, d, h, m, sec = [int(x or 0) for x in match.groups()]\n            return dt.timedelta(weeks=w, days=d, hours=h, minutes=m, seconds=sec)\n        return dt.timedelta(0) if isinstance(start, dt.datetime) else DAY\n\n\ndef month_days(year, month, rule, default):\n    n = calendar.monthrange(year, month)[1]\n    days = set(range(1, n + 1))\n    if 'BYMONTHDAY' in rule:\n        days &= {v if v > 0 else n + v + 1 for v in map(int, rule['BYMONTHDAY'].split(','))}\n    if 'BYDAY' in rule:\n        selected = set()\n        for token in rule['BYDAY'].split(','):\n            weekday = WEEKDAYS.index(token[-2:])\n            matching = [d for d in range(1, n + 1) if dt.date(year, month, d).weekday() == weekday]\n            if token[:-2]:\n                ordinal = int(token[:-2])\n                index = ordinal - 1 if ordinal > 0 else ordinal\n                if -len(matching) <= index < len(matching):\n                    selected.add(matching[index])\n            else:\n                selected.update(matching)\n        days &= selected\n    if 'BYMONTHDAY' not in rule and 'BYDAY' not in rule:\n        days &= {default}\n    return sorted(days)\n\n\ndef candidates(start, rule, horizon):\n    date = start.date() if isinstance(start, dt.datetime) else start\n    freq = rule['FREQ']\n    interval = int(rule.get('INTERVAL', 1))\n    if interval <= 0:\n        return\n    def wall(d):\n        return dt.datetime.combine(d, start.time()) if isinstance(start, dt.datetime) else d\n    if freq in ('MONTHLY', 'YEARLY'):\n        year, month = date.year, date.month\n        while year <= horizon.year:\n            months = [month] if freq == 'MONTHLY' else sorted(set(map(int, rule.get('BYMONTH', str(date.month)).split(','))))\n            for mo in months:\n                if not 1 <= mo <= 12:\n                    continue\n                if freq == 'MONTHLY' and 'BYMONTH' in rule and mo not in map(int, rule['BYMONTH'].split(',')):\n                    continue\n                for day in month_days(year, mo, rule, date.day):\n                    d = dt.date(year, mo, day)\n                    if date <= d <= horizon:\n                        yield wall(d)\n            if freq == 'YEARLY':\n                year += interval\n            else:\n                total = year * 12 + month - 1 + interval\n                year, mo = divmod(total, 12)\n                month = mo + 1\n                if (year, month) > (horizon.year, horizon.month):\n                    break\n        return\n    d = date\n    week_start = date - dt.timedelta(days=date.weekday())\n    byday = {WEEKDAYS.index(x[-2:]) for x in rule.get('BYDAY', WEEKDAYS[date.weekday()]).split(',')}\n    while d <= horizon:\n        valid = freq == 'DAILY' or ((d - week_start).days // 7 % interval == 0 and d.weekday() in byday)\n        if valid and 'BYMONTH' in rule:\n            valid = d.month in map(int, rule['BYMONTH'].split(','))\n        if valid and 'BYMONTHDAY' in rule:\n            n = calendar.monthrange(d.year, d.month)[1]\n            valid = d.day in {v if v > 0 else n + v + 1 for v in map(int, rule['BYMONTHDAY'].split(','))}\n        if valid and freq == 'DAILY' and 'BYDAY' in rule:\n            valid = d.weekday() in byday\n        if valid:\n            yield wall(d)\n        step = interval if freq == 'DAILY' else 1\n        if (horizon - d).days < step:\n            break\n        d += dt.timedelta(days=step)\n\n\ndef solve(config, base):\n    engine = Engine(config)\n    path = config.get('ics', config.get('calendar', 'calendar.ics'))\n    events = parse((base / path).read_text())\n    ws, we = instant(config['window_start']), instant(config['window_end'])\n    overrides = {}\n    for e in events:\n        if 'RECURRENCE-ID' in e:\n            overrides[(e.get('UID', ({}, ''))[1], engine.key(e['RECURRENCE-ID']))] = e\n    result = []\n    def emit(e, start, override=False):\n        if e.get('STATUS', ({}, ''))[1].upper() == 'CANCELLED':\n            return\n        end = start + engine.length(e)\n        timed = isinstance(start, dt.datetime)\n        lo, hi = (ws, we) if timed else (ws.date(), we.date())\n        if not ((lo <= start < hi) if end == start else (start < hi and end > lo)):\n            return\n        summary = e.get('SUMMARY', ({}, ''))[1]\n        summary = re.sub(r'\\\\\\\\([\\\\\\\\;,nN])', lambda m: '\\\\n' if m[1] in 'nN' else m[1], summary)\n        fmt = lambda x: x.strftime('%Y-%m-%dT%H:%M:%SZ') if timed else x.isoformat()\n        result.append(dict(uid=e.get('UID', ({}, ''))[1], summary=summary, start=fmt(start), end=fmt(end), all_day=not timed, override=override))\n    for event in events:\n        if 'RECURRENCE-ID' in event or 'DTSTART' not in event:\n            continue\n        uid = event.get('UID', ({}, ''))[1]\n        local, zone = engine.date(event['DTSTART'])\n        starts = set()\n        if 'RRULE' in event:\n            rule = dict(part.split('=', 1) for part in event['RRULE'][1].upper().split(';'))\n            horizon = we.date() + dt.timedelta(days=3)\n            for (u, key) in overrides:\n                if u == uid:\n                    horizon = max(horizon, (key.date() if isinstance(key, dt.datetime) else key) + dt.timedelta(days=3))\n            until = None\n            if 'UNTIL' in rule:\n                until = engine.key(({}, rule['UNTIL']))\n                if isinstance(local, dt.datetime) and not isinstance(until, dt.datetime):\n                    until = dt.datetime.combine(until, dt.time(23, 59, 59))\n                elif not isinstance(local, dt.datetime) and isinstance(until, dt.datetime):\n                    until = until.date()\n                horizon = min(horizon, (until.date() if isinstance(until, dt.datetime) else until) + dt.timedelta(days=2))\n            count = 0\n            for candidate in candidates(local, rule, horizon):\n                key = engine.utc(candidate, zone) if isinstance(candidate, dt.datetime) else candidate\n                if until is not None and key > until:\n                    continue\n                count += 1\n                if count > int(rule.get('COUNT', 10**30)):\n                    break\n                starts.add(key)\n        else:\n            starts.add(engine.key(event['DTSTART']))\n        for params, values in event.get('RDATE', []):\n            starts.update(engine.key((params, value)) for value in values.split(','))\n        excluded = set()\n        for params, values in event.get('EXDATE', []):\n            excluded.update(engine.key((params, value)) for value in values.split(','))\n        for start in starts - excluded:\n            override = overrides.get((uid, start))\n            if override is not None:\n                if 'DTSTART' in override:\n                    emit(override, engine.key(override['DTSTART']), True)\n            else:\n                emit(event, start)\n    result.sort(key=lambda o: (o['start'] if not o['all_day'] else o['start'] + 'T00:00:00Z', o['uid']))\n    return dict(occurrences=result, count=len(result), events_parsed=len(events))\n\n\nif __name__ == '__main__':\n    source = Path(sys.argv[1])\n    answer = solve(json.loads(source.read_text()), source.resolve().parent)\n    Path(sys.argv[2]).write_text(json.dumps(answer, indent=2) + '\\\\n')\nPY\npython3 solve.py input.json answer.json\npython3 - <<'PY'\nimport json\nfrom collections import Counter\nx=json.load(open('answer.json'))\nprint(x['count'], x['events_parsed'])\nprint(Counter(o['summary'] for o in x['occurrences']))\nPY\"", "aggregated_output": "126 11\nCounter({'Daily weather\\nbriefing': 75, 'Weekly crew briefing, dock 2': 22, 'Haul-out day (all day)': 13, 'Last Friday race night': 6, 'Month-end fuel check': 4, 'Annual survey': 2, 'Briefing moved': 1, 'Gap test': 1, 'Zero length mark': 1, 'Overlap test': 1})\n", "exit_code": 0, "status": "completed"}}
{"type": "item.completed", "item": {"id": "item_6", "type": "agent_message", "text": "The supplied calendar produces 126 occurrences from 11 VEVENT blocks. I\u2019m checking DST gap/overlap conversion, monthly day intersections, and COUNT handling before EXDATE removal."}}
{"type": "item.started", "item": {"id": "item_7", "type": "command_execution", "command": "/bin/bash -lc \"python3 - <<'PY'\nimport datetime as d\nfrom pathlib import Path\nfrom solve import Engine, parse, candidates, solve\nimport json\ncfg=json.load(open('input.json'))\ne=Engine(cfg)\nassert e.utc(d.datetime(2026,3,8,2,30),'Test/West') == d.datetime(2026,3,8,7,30)\nassert e.utc(d.datetime(2026,11,1,1,30),'Test/West') == d.datetime(2026,11,1,5,30)\nr={'FREQ':'MONTHLY','BYDAY':'MO','BYMONTHDAY':'1,2,3,4,5,6,7'}\nassert list(candidates(d.date(2026,1,1),r,d.date(2026,3,31))) == [d.date(2026,1,5),d.date(2026,2,2),d.date(2026,3,2)]\np=parse('BEGIN:VEVENT\\\\nSUMMARY;X=\\\"a;b:c\\\":one\\\\\\\\,two\\\\n folded\\\\nBEGIN:VALARM\\\\nSUMMARY:bad\\\\nEND:VALARM\\\\nSUMMARY:ignored\\\\nEND:VEVENT\\\\n')\nassert p[0]['SUMMARY'][1] == 'one\\\\\\\\,twofolded'\nfixture=Path('/tmp/calendar-count-check.ics')\nfixture.write_text('BEGIN:VCALENDAR\\\\nBEGIN:VEVENT\\\\nUID:test\\\\nDTSTART:20261001T120000Z\\\\nRRULE:FREQ=DAILY;COUNT=2\\\\nEXDATE:20261001T120000Z\\\\nRDATE:20261004T120000Z\\\\nEND:VEVENT\\\\nEND:VCALENDAR\\\\n')\nc={'ics':str(fixture),'timezones':{},'window_start':'2026-10-01T00:00:00Z','window_end':'2026-10-05T00:00:00Z'}\na=solve(c,Path('/tmp'))\nassert [o['start'] for o in a['occurrences']] == ['2026-10-02T12:00:00Z','2026-10-04T12:00:00Z']\nprint('All targeted checks passed.')\nPY\npython3 -m py_compile solve.py\"", "aggregated_output": "", "exit_code": null, "status": "in_progress"}}
{"type": "item.completed", "item": {"id": "item_7", "type": "command_execution", "command": "/bin/bash -lc \"python3 - <<'PY'\nimport datetime as d\nfrom pathlib import Path\nfrom solve import Engine, parse, candidates, solve\nimport json\ncfg=json.load(open('input.json'))\ne=Engine(cfg)\nassert e.utc(d.datetime(2026,3,8,2,30),'Test/West') == d.datetime(2026,3,8,7,30)\nassert e.utc(d.datetime(2026,11,1,1,30),'Test/West') == d.datetime(2026,11,1,5,30)\nr={'FREQ':'MONTHLY','BYDAY':'MO','BYMONTHDAY':'1,2,3,4,5,6,7'}\nassert list(candidates(d.date(2026,1,1),r,d.date(2026,3,31))) == [d.date(2026,1,5),d.date(2026,2,2),d.date(2026,3,2)]\np=parse('BEGIN:VEVENT\\\\nSUMMARY;X=\\\"a;b:c\\\":one\\\\\\\\,two\\\\n folded\\\\nBEGIN:VALARM\\\\nSUMMARY:bad\\\\nEND:VALARM\\\\nSUMMARY:ignored\\\\nEND:VEVENT\\\\n')\nassert p[0]['SUMMARY'][1] == 'one\\\\\\\\,twofolded'\nfixture=Path('/tmp/calendar-count-check.ics')\nfixture.write_text('BEGIN:VCALENDAR\\\\nBEGIN:VEVENT\\\\nUID:test\\\\nDTSTART:20261001T120000Z\\\\nRRULE:FREQ=DAILY;COUNT=2\\\\nEXDATE:20261001T120000Z\\\\nRDATE:20261004T120000Z\\\\nEND:VEVENT\\\\nEND:VCALENDAR\\\\n')\nc={'ics':str(fixture),'timezones':{},'window_start':'2026-10-01T00:00:00Z','window_end':'2026-10-05T00:00:00Z'}\na=solve(c,Path('/tmp'))\nassert [o['start'] for o in a['occurrences']] == ['2026-10-02T12:00:00Z','2026-10-04T12:00:00Z']\nprint('All targeted checks passed.')\nPY\npython3 -m py_compile solve.py\"", "aggregated_output": "All targeted checks passed.\n", "exit_code": 0, "status": "completed"}}
{"type": "item.completed", "item": {"id": "item_8", "type": "agent_message", "text": "Implemented [solve.py](/home/bob/usecase-runs/batch/out/gpt-6.1-sol/129_m10/work/solve.py).\n\nVerified parsing, DST transitions, monthly filters, and COUNT/EXDATE behavior. The supplied calendar produces 126 occurrences from 11 events in `answer.json`."}}
{"type": "turn.completed", "usage": {"input_tokens": 131230, "cached_input_tokens": 104576, "cache_write_input_tokens": 0, "output_tokens": 4239, "reasoning_output_tokens": 234}}