import requests
import json
import os
from datetime import datetime, timedelta


def gen_auth_token(auth_file):
    
    url = "https://ngw.devices.sberbank.ru:9443/api/v2/oauth"

    payload='scope=GIGACHAT_API_CORP'
    headers = {
    'Content-Type': 'application/x-www-form-urlencoded',
    'Accept': 'application/json',
    'RqUID': '1b519047-0ee9-4b63-8599-e5ffc9c77e72',
    'Authorization': os.getenv('GIGACHAT_API_TOKEN')
    }

    response = requests.request("POST", url, headers=headers, data=payload, verify=False)

    with open(auth_file, 'w') as f:
        json.dump(json.loads(response.text), f, ensure_ascii=False)


def get_text(content='Привет!', auth_token=None):
    url = "https://gigachat.devices.sberbank.ru/api/v1/chat/completions"

    payload = json.dumps({
    "model": "GigaChat",
    "messages": [
        {
        "role": "user",
        "content": content
        }
    ],
    "temperature": 1,
    "top_p": 0.1,
    "n": 1,
    "stream": False,
    "max_tokens": 512,
    "repetition_penalty": 1
    })
    headers = {
    'Content-Type': 'application/json',
    'Accept': 'application/json',
    'Authorization': f'Bearer {auth_token}'
    }

    response = requests.request("POST", url, headers=headers, data=payload, verify=False)

    return json.loads(response.text)


def generate(content='Привет!', auth_file=None):
    if auth_file is None or not os.path.isfile(auth_file):
        gen_auth_token(auth_file)

    with open(auth_file) as f:
        auth_token = json.load(f)
    
    if datetime.fromtimestamp(auth_token['expires_at']/1000) <= datetime.now() - timedelta(seconds=60):
        gen_auth_token()
        with open(auth_file) as f:
            auth_token = json.load(f)

    resp = get_text(content, auth_token['access_token'])
    
    return resp["choices"][0]["message"]["content"]