{"files": {"main.py": "from core import run\nfrom policy import POLICY\ndef evaluate(payload):\n    return run(payload, POLICY)\n", "core.py": "import copy\nfrom helpers import ascii_fold, merge_fields\n\nALLOWED_FIELDS = {\"name\", \"tags\", \"meta\"}\n\ndef run(payload, policy):\n    if isinstance(payload, dict):\n        events = payload.get(\"events\", [])\n    elif isinstance(payload, (list, tuple)):\n        events = list(payload)\n    else:\n        events = []\n    trim_ids = bool(policy.get(\"trim_ids\", False))\n    fold_case = bool(policy.get(\"fold_case\", False))\n    empty_id = policy.get(\"empty_id\", \"error\")\n    version_floor = policy.get(\"version_floor\", 0)\n    duplicate_policy = policy.get(\"duplicate_policy\", \"first\")\n    selected = {}\n    for original_index, event in enumerate(events):\n        raw_id = event.get(\"id\", \"\")\n        if not isinstance(raw_id, str):\n            raw_id = str(raw_id)\n        normalized = raw_id.strip() if trim_ids else raw_id\n        if fold_case:\n            normalized = ascii_fold(normalized)\n        if normalized == \"\":\n            if empty_id == \"error\":\n                raise ValueError(\"empty id\")\n            continue\n        version = event.get(\"version\", 0)\n        if version < version_floor:\n            continue\n        key = (normalized, version)\n        entry = {\"id\": normalized, \"version\": version, \"index\": original_index, \"event\": event}\n        if key not in selected:\n            selected[key] = entry\n        elif duplicate_policy == \"last\":\n            selected[key] = entry\n    ordered = sorted(selected.values(), key=lambda item: (item[\"version\"], item[\"index\"]))\n    records = {}\n    tombstones = set()\n    first_processed = {}\n    audit = []\n    audit_all = bool(policy.get(\"audit_all\", False))\n    tombstone_wins = bool(policy.get(\"tombstone_wins\", False))\n    unknown_fields = policy.get(\"unknown_fields\", \"keep\")\n    for processed_index, item in enumerate(ordered):\n        normalized = item[\"id\"]\n        version = item[\"version\"]\n        event = item[\"event\"]\n        if normalized not in first_processed:\n            first_processed[normalized] = processed_index\n        deleted = bool(event.get(\"deleted\", False))\n        applied = False\n        if deleted:\n            if normalized in records:\n                del records[normalized]\n                if tombstone_wins:\n                    tombstones.add(normalized)\n                applied = True\n            elif tombstone_wins and normalized not in tombstones:\n                tombstones.add(normalized)\n                applied = True\n            else:\n                applied = False\n        else:\n            if tombstone_wins and normalized in tombstones:\n                applied = False\n            else:\n                if normalized not in records:\n                    records[normalized] = {}\n                fields = event.get(\"fields\", {})\n                if not isinstance(fields, dict):\n                    fields = {}\n                if unknown_fields == \"drop\":\n                    fields = {key: value for key, value in fields.items() if key in ALLOWED_FIELDS}\n                else:\n                    fields = dict(fields)\n                merge_fields(records[normalized], fields, policy)\n                applied = True\n        if audit_all or applied:\n            audit.append(f\"{normalized}:{version}:{'applied' if applied else 'blocked'}\")\n    if policy.get(\"order\", \"input\") == \"id\":\n        record_ids = sorted(records.keys())\n    else:\n        record_ids = sorted(records.keys(), key=lambda rid: (first_processed.get(rid, 0), rid))\n    output_records = [{\"id\": rid, \"fields\": copy.deepcopy(records[rid])} for rid in record_ids]\n    return {\"records\": output_records, \"audit\": audit}\n", "policy.py": "POLICY = {\"audit_all\": false, \"duplicate_policy\": \"last\", \"empty_id\": \"error\", \"fold_case\": false, \"list_merge\": \"unique\", \"nested_merge\": false, \"null_mode\": \"delete\", \"order\": \"input\", \"tombstone_wins\": false, \"trim_ids\": false, \"unknown_fields\": \"drop\", \"version_floor\": 3}\n", "helpers.py": "import copy\n\ndef ascii_fold(value):\n    return \"\".join(chr(ord(char) + 32) if \"A\" <= char <= \"Z\" else char for char in value)\n\ndef json_equal(left, right):\n    if isinstance(left, bool) or isinstance(right, bool):\n        return isinstance(left, bool) and isinstance(right, bool) and left == right\n    if isinstance(left, (int, float)) and isinstance(right, (int, float)):\n        return left == right\n    if type(left) is not type(right):\n        return False\n    if isinstance(left, dict):\n        if set(left.keys()) != set(right.keys()):\n            return False\n        return all(json_equal(left[key], right[key]) for key in left)\n    if isinstance(left, list):\n        if len(left) != len(right):\n            return False\n        return all(json_equal(a, b) for a, b in zip(left, right))\n    return left == right\n\ndef merge_fields(target, source, policy):\n    null_mode = policy.get(\"null_mode\", \"delete\")\n    nested_merge = bool(policy.get(\"nested_merge\", False))\n    list_merge = policy.get(\"list_merge\", \"replace\")\n    for key, value in source.items():\n        if value is None:\n            if null_mode == \"delete\":\n                target.pop(key, None)\n            continue\n        if key in target:\n            existing = target[key]\n            if nested_merge and isinstance(existing, dict) and isinstance(value, dict):\n                merge_fields(existing, value, policy)\n            elif list_merge == \"unique\" and isinstance(existing, list) and isinstance(value, list):\n                old_items = list(existing)\n                for item in value:\n                    if not any(json_equal(item, old_item) for old_item in old_items):\n                        existing.append(copy.deepcopy(item))\n            else:\n                target[key] = copy.deepcopy(value)\n        else:\n            target[key] = copy.deepcopy(value)\n    return target\n"}}