{"files":{"main.py":"from core import run\nfrom policy import POLICY\ndef evaluate(payload):\n    return run(payload, POLICY)\n","policy.py":"POLICY = {\n    'duplicate_policy': 'first',\n    'fold_case': True,\n    'tombstone_wins': True,\n    'trim_ids': True,\n    'list_merge': 'replace',\n    'nested_merge': True,\n    'null_mode': 'ignore',\n    'version_floor': 2,\n    'audit_all': True,\n    'empty_id': 'skip',\n    'order': 'id',\n    'unknown_fields': 'keep',\n}\n","helpers.py":"import copy\n\n\ndef jeq(a, b):\n    if isinstance(a, bool) or isinstance(b, bool):\n        return isinstance(a, bool) and isinstance(b, bool) and a == b\n    if isinstance(a, dict) and isinstance(b, dict):\n        if set(a.keys()) != set(b.keys()):\n            return False\n        return all(jeq(a[k], b[k]) for k in a)\n    if isinstance(a, list) and isinstance(b, list):\n        return len(a) == len(b) and all(jeq(x, y) for x, y in zip(a, b))\n    if isinstance(a, (dict, list)) or isinstance(b, (dict, list)):\n        return False\n    if a is None or b is None:\n        return a is None and b is None\n    if isinstance(a, str) != isinstance(b, str):\n        return False\n    return a == b\n\n\ndef fold(s):\n    return ''.join(chr(ord(c) + 32) if 'A' <= c <= 'Z' else c for c in s)\n\n\ndef merge(old, new, policy):\n    res = dict(old)\n    for k, v in new.items():\n        if v is None:\n            if policy['null_mode'] == 'delete':\n                res.pop(k, None)\n            continue\n        if k in res:\n            ov = res[k]\n            if policy['nested_merge'] and isinstance(ov, dict) and isinstance(v, dict):\n                res[k] = merge(ov, v, policy)\n                continue\n            if isinstance(ov, list) and isinstance(v, list) and policy['list_merge'] == 'unique':\n                extra = [copy.deepcopy(x) for x in v if not any(jeq(x, o) for o in ov)]\n                res[k] = list(ov) + extra\n                continue\n        res[k] = copy.deepcopy(v)\n    return res\n","core.py":"import copy\nfrom helpers import merge, fold\n\n\ndef run(payload, policy):\n    if isinstance(payload, dict):\n        events = payload.get('events', [])\n    else:\n        events = payload\n    groups = {}\n    for i, ev in enumerate(events):\n        nid = ev.get('id')\n        if not isinstance(nid, str):\n            nid = '' if nid is None else str(nid)\n        if policy['trim_ids']:\n            nid = nid.strip()\n        if policy['fold_case']:\n            nid = fold(nid)\n        if nid == '':\n            if policy['empty_id'] == 'error':\n                raise ValueError('empty id')\n            continue\n        ver = ev.get('version')\n        if ver < policy['version_floor']:\n            continue\n        key = (nid, ver)\n        if key not in groups:\n            groups[key] = i\n        elif policy['duplicate_policy'] == 'last':\n            groups[key] = i\n    sel = [(k[1], i, k[0]) for k, i in groups.items()]\n    sel.sort(key=lambda t: (t[0], t[1]))\n    records = {}\n    tomb = set()\n    first = {}\n    audit = []\n    for pos, (ver, idx, nid) in enumerate(sel):\n        ev = events[idx]\n        if nid not in first:\n            first[nid] = pos\n        applied = False\n        if ev.get('deleted'):\n            if policy['tombstone_wins']:\n                if nid in tomb:\n                    applied = False\n                else:\n                    records.pop(nid, None)\n                    tomb.add(nid)\n                    applied = True\n            else:\n                if nid in records:\n                    del records[nid]\n                    applied = True\n        else:\n            if policy['tombstone_wins'] and nid in tomb:\n                applied = False\n            else:\n                old = records.get(nid, {})\n                records[nid] = merge(old, ev.get('fields') or {}, policy)\n                applied = True\n        if applied or policy['audit_all']:\n            audit.append('%s:%s:%s' % (nid, ver, 'applied' if applied else 'blocked'))\n    ids = list(records.keys())\n    if policy['order'] == 'id':\n        ids.sort()\n    else:\n        ids.sort(key=lambda n: (first[n], n))\n    out = []\n    for n in ids:\n        f = records[n]\n        if policy['unknown_fields'] == 'drop':\n            f = {k: v for k, v in f.items() if k in ('name', 'tags', 'meta')}\n        out.append({'id': n, 'fields': copy.deepcopy(f)})\n    return {'records': out, 'audit': audit}\n"}}