import json

MIN_PRESSURE_PA = 25.0  # 防煙樓梯間最低正壓要求
MAX_PRESSURE_PA = 50.0

def lambda_handler(event, context):
    station_code = event.get("station_code", "unknown")
    system_code = event.get("system_code", "unknown")
    pressure_pa = event.get("pressure_pa")

    if pressure_pa is None:
        return {"statusCode": 400, "body": "缺少pressure_pa欄位"}

    if pressure_pa < MIN_PRESSURE_PA or pressure_pa > MAX_PRESSURE_PA:
        print(f"[異常] 車站{station_code} {system_code}"
            f" 壓力{pressure_pa}Pa超出設計範圍({MIN_PRESSURE_PA}~{MAX_PRESSURE_PA}Pa)")
        # 此處可接續呼叫SNS通知該車站值班人員與總控中心
    else:
        print(f"車站{station_code} {system_code} 壓力正常：{pressure_pa}Pa")

    return {"statusCode": 200, "body": json.dumps("處理完成")}