"""表存在性审计：`baseline_generated.sql` 声明的表 vs MySQL 实际表。

与另两个工具互补：
- `tools/audit_constraints.py`：唯一键 ↔ 文档基线、ORM 映射 ↔ 库列名；
- `tools/schema_fingerprint.py`：字段、索引与外键的结构指纹；
- 本脚本：表名集合与列存在性。

凭据来自 `.env` 的 `MYSQL_DSN`，不在脚本内硬编码口令。
"""

from __future__ import annotations

import re
import sys
from pathlib import Path

from sqlalchemy import create_engine, text

ROOT = Path(__file__).resolve().parents[1]
sys.path.insert(0, str(ROOT))

from app.core.config import get_settings  # noqa: E402

SQL_FILE = ROOT / "alembic" / "baseline_generated.sql"

# baseline_generated.sql 只覆盖基线表；以下平台增量表由 Alembic 迁移创建。
INCREMENTAL_TABLES = {
    "agent_run",
    "domain_event_outbox",
    "request_idempotency",
    "config_release",
    "platform_config_item",
    "model_endpoint_config",
    "model_routing_rule",
    "model_routing_fallback",
    "prompt_template_version",
    "outbox_delivery",
    "svc_conversation_session",
    "api_request_receipt",
    "offsite_fund_mail",
    "offsite_mail_cursor",
    "offsite_fund_attachment",
    "offsite_fund_document",
    "offsite_execution_plan_task",
    "offsite_rule_result",
    "offsite_query_record",
    "offsite_notification",
}


def expected_tables() -> set[str]:
    content = SQL_FILE.read_text(encoding="utf-8")
    return set(re.findall(r"CREATE TABLE `?([A-Za-z0-9_]+)`?", content))


def main() -> int:
    engine = create_engine(get_settings().mysql_dsn.replace("mysql+asyncmy", "mysql+pymysql"))
    with engine.connect() as connection:
        actual = set(
            connection.execute(
                text(
                    "SELECT TABLE_NAME FROM information_schema.TABLES "
                    "WHERE TABLE_SCHEMA = DATABASE()"
                )
            )
            .scalars()
            .all()
        ) - {"alembic_version"}
        expected = expected_tables() | INCREMENTAL_TABLES
        missing = expected - actual
        unexpected = actual - expected
        if missing or unexpected:
            print(f"schema audit FAILED: missing={sorted(missing)} unexpected={sorted(unexpected)}")
            return 1
        rows = connection.execute(
            text(
                "SELECT TABLE_NAME, COLUMN_NAME FROM information_schema.COLUMNS "
                "WHERE TABLE_SCHEMA = DATABASE()"
            )
        ).all()
    engine.dispose()

    column_counts: dict[str, int] = {}
    for table, _column in rows:
        column_counts[table] = column_counts.get(table, 0) + 1
    without_columns = sorted(table for table in expected if not column_counts.get(table))
    if without_columns:
        print(f"schema audit FAILED: tables without columns: {without_columns}")
        return 1

    print(f"schema audit passed: {len(expected)} business tables, no missing or unexpected tables")
    return 0


if __name__ == "__main__":
    raise SystemExit(main())