# 作者：北小菜
"""轻量 SQLite 列升级（无 Django migrations 时使用）"""
import logging

logger = logging.getLogger("app.schema")


def _table_columns(cursor, table):
    if table not in {"av_biz_algorithm"}:
        raise ValueError("table is not allowed for schema upgrade")
    cursor.execute('PRAGMA table_info("av_biz_algorithm")')
    return {row[1] for row in cursor.fetchall()}


def ensure_biz_algorithm_line_count_columns():
    from django.db import connection

    table = "av_biz_algorithm"
    adds = {
        "forward_count_threshold": "ALTER TABLE av_biz_algorithm ADD COLUMN forward_count_threshold INTEGER NOT NULL DEFAULT 0",
        "reverse_count_threshold": "ALTER TABLE av_biz_algorithm ADD COLUMN reverse_count_threshold INTEGER NOT NULL DEFAULT 0",
        "detector_model_id": "ALTER TABLE av_biz_algorithm ADD COLUMN detector_model_id INTEGER NULL",
    }
    with connection.cursor() as cur:
        existing = _table_columns(cur, table)
        for col, sql in adds.items():
            if col in existing:
                continue
            cur.execute(sql)
            logger.info("schema upgrade: %s", sql)