"""
ADR-073 回填腳本：修補存量 incidents 三個 NULL 欄位
- alertname
- notification_type
- alert_category

根本原因：save_to_episodic_memory() 建立 IncidentRecord 時漏掉這三個欄位。
2026-04-12 ogt (ADR-073 修補 Fix #1)

執行方式:
    kubectl exec -n awoooi-prod <api-pod> -- python3 /app/scripts/backfill_alertname.py
"""
import asyncio
import sys
sys.path.insert(0, "/app")

from sqlalchemy import text

from src.db.base import get_db_context
from src.services.incident_service import classify_alert_early


async def main() -> None:
    async with get_db_context() as db:
        # --- Step 1: 統計目前 NULL 狀況 ---
        null_r = await db.execute(text("""
            SELECT
                COUNT(*) FILTER (WHERE alertname IS NULL) AS alertname_null,
                COUNT(*) FILTER (WHERE notification_type IS NULL) AS notification_type_null,
                COUNT(*) FILTER (WHERE alert_category IS NULL) AS alert_category_null,
                COUNT(*) AS total
            FROM incidents
        """))
        row = null_r.fetchone()
        print(f"總計: {row.total} 筆")
        print(f"  alertname NULL:        {row.alertname_null}")
        print(f"  notification_type NULL: {row.notification_type_null}")
        print(f"  alert_category NULL:   {row.alert_category_null}")

        # --- Step 2: SQL 回填 alertname ---
        # signals 是 JSONB array，Signal 模型序列化後的 key 是 alert_name
        # labels dict 裡也有 alertname key
        result = await db.execute(text("""
            UPDATE incidents
            SET alertname = COALESCE(
                signals->0->'labels'->>'alertname',
                signals->0->>'alert_name',
                signals->0->>'alertname'
            )
            WHERE alertname IS NULL
              AND signals IS NOT NULL
              AND json_array_length(signals) > 0
        """))
        await db.commit()
        print(f"\n✅ alertname 回填: {result.rowcount} 筆")

        # --- Step 3: Python 回填 notification_type + alert_category ---
        # 需要 Python 跑分類邏輯，從 DB 讀出 alertname + severity 批次更新
        rows_r = await db.execute(text("""
            SELECT incident_id, alertname, severity
            FROM incidents
            WHERE (notification_type IS NULL OR alert_category IS NULL)
              AND alertname IS NOT NULL
        """))
        rows = rows_r.fetchall()
        print(f"\n待分類回填: {len(rows)} 筆")

        updated = 0
        for row in rows:
            alert_category, notification_type = classify_alert_early(
                alertname=row.alertname or "",
                severity=row.severity or "warning",
                labels={},
            )
            await db.execute(text("""
                UPDATE incidents
                SET notification_type = :notification_type,
                    alert_category = :alert_category
                WHERE incident_id = :incident_id
            """), {
                "notification_type": notification_type,
                "alert_category": alert_category,
                "incident_id": row.incident_id,
            })
            updated += 1

        await db.commit()
        print(f"✅ notification_type + alert_category 回填: {updated} 筆")

        # --- Step 4: 最終統計 ---
        final_r = await db.execute(text("""
            SELECT
                COUNT(*) FILTER (WHERE alertname IS NULL) AS alertname_null,
                COUNT(*) FILTER (WHERE notification_type IS NULL) AS notification_type_null,
                COUNT(*) FILTER (WHERE alert_category IS NULL) AS alert_category_null
            FROM incidents
        """))
        f = final_r.fetchone()
        print("\n最終 NULL 統計:")
        print(f"  alertname NULL:        {f.alertname_null}")
        print(f"  notification_type NULL: {f.notification_type_null}")
        print(f"  alert_category NULL:   {f.alert_category_null}")

        if f.alertname_null == 0 and f.notification_type_null == 0 and f.alert_category_null == 0:
            print("\n✅ 三個欄位全部回填完成")
        else:
            print("\n⚠️ 部分記錄仍為 NULL (可能 signals 為空或格式異常)")


if __name__ == "__main__":
    asyncio.run(main())