import asyncio
import base64
import json
import os

from datetime import datetime
from cryptography.hazmat.primitives import serialization
from cryptography.hazmat.primitives.asymmetric import padding
from cryptography.hazmat.primitives import hashes
from app.config.const import SYSTEM_ID, SYSTEM_STATUS_EXPIRED, SYSTEM_STATUS_ON, APP_SERVICE_PATH
from app.models import SystemDataModel
from app.models.base_model import SessionLocal
from app.utils.common import get_machine_id


async def sync_system_license():
    print("-------------------------------------------")
    db = SessionLocal()
    try:
        system = db.query(SystemDataModel).filter_by(id=SYSTEM_ID).first()
        if not system:
            return
        machine_id = get_machine_id()
        if system.machine_id:
            if system.machine_id != machine_id:
                system.machine_id = machine_id
                if system.status == SYSTEM_STATUS_ON:
                    system.status = SYSTEM_STATUS_EXPIRED
            else:
                if system.status == SYSTEM_STATUS_ON:
                    if not system.license_code or system.expired_at < datetime.now():
                        system.status = SYSTEM_STATUS_EXPIRED
                    else:
                        try:
                            with open(os.path.join(APP_SERVICE_PATH, "pom/public_key.pem"), "rb") as f:
                                public_key = serialization.load_pem_public_key(f.read())
                            license_data, signature = base64.b64decode(system.license_code).split(b"-----", 1)
                            # print(license_data)
                            public_key.verify(
                                signature,
                                license_data,
                                padding.PSS(
                                    mgf=padding.MGF1(hashes.SHA256()),
                                    salt_length=padding.PSS.MAX_LENGTH
                                ),
                                hashes.SHA256()
                            )
                            license_dict = json.loads(license_data.decode('utf-8'))
                            # print(license_dict)
                            expiration_date = datetime.fromisoformat(license_dict['expiration_date'])
                            system.expired_at = expiration_date
                            if expiration_date < datetime.now():
                                system.status = SYSTEM_STATUS_EXPIRED
                        except Exception as e:
                            print(e)
                            system.status = SYSTEM_STATUS_EXPIRED
        else:
            if system.status == SYSTEM_STATUS_ON:
                system.status = SYSTEM_STATUS_EXPIRED
        db.commit()
    except Exception as e:
        print(e)
    finally:
        db.close()


def sync_resource():
    asyncio.run(sync_system_license())