import json
import os
import time
import requests
from threading import Event


class Access:
    PENDING = 1
    PROCESS = 2
    GENERATE = 3
    FINISH = 4
    ERROR = 5

    url = None
    username = None
    password = None

    token = None
    refresh = None
    refresh_time = None
    headers = None

    refreshing = Event()

    def __init__(self):
        self.read_credentials()
        self.get_token()
        self.refreshing.set()

    def read_credentials(self):
        folder_path = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
        config_path = os.path.join(folder_path, "config/api_config.json")
        with open(config_path, "r") as f:
            params = json.load(f)

        self.refreshing.clear()
        self.url = params['url']
        self.username = params['username']
        self.password = params['password']
        self.refreshing.set()

    def format_header(self):
        self.headers = {
            'Authorization': f'Bearer {self.token}'
        }

    def is_time_for_refreshing(self):
        return self.refresh_time < time.time()

    def get_token(self):
        json_form = {
            'grantType': 'password',
            'username': self.username,
            'password': self.password
        }
        response = requests.post(f'{self.url}/token', json=json_form)

        if response.status_code == 400:
            raise Exception('400 Bad request: invalid login and/or password.')
        elif response.status_code == 200:
            self.refreshing.clear()
            self.token = response.json()['accessToken']
            self.refresh = response.json()['refreshToken']
            self.refresh_time = response.json()['expiresIn']
            self.format_header()
            self.refreshing.set()
        else:
            raise Exception(f'{response.status_code}')

    def refresh_token(self):
        json_form = {
            'grantType': 'refresh_token',
            'refreshToken': self.refresh
        }
        response = requests.post(f'{self.url}/token', json=json_form)

        if response.status_code == 400:
            raise Exception('400 Bad request: wrong request parameters for refreshing.')
        elif response.status_code == 401:
            self.get_token()
        elif response.status_code == 200:
            self.refreshing.clear()
            self.token = response.json()['accessToken']
            self.refresh = response.json()['refreshToken']
            self.refresh_time = response.json()['expiresIn']
            self.format_header()
            self.refreshing.set()
        else:
            raise Exception(f'{response.status_code}')

    def get_doc(self, doc_id):
        if self.is_time_for_refreshing():
            self.refresh_token()

        self.refreshing.wait()
        response = requests.get(f'{self.url}/doc-convert/{doc_id}/file', headers=self.headers)

        if response.status_code == 404:
            raise FileNotFoundError('404 Not Found: file have not found.')
        elif response.status_code == 200:
            content = response.content
        else:
            raise Exception(f'{response.status_code}')

        return content

    def send_image(self, img, doc_id):
        if self.is_time_for_refreshing():
            self.refresh_token()

        self.refreshing.wait()

        with open(img, 'rb') as img_file:
            files = {
                'image': (os.path.basename(img), img_file)
            }
            response = requests.post(f'{self.url}/doc-convert/image', files=files, headers=self.headers)

        if response.status_code == 400:
            self.update_status(doc_id, self.ERROR)
            raise Exception(f'400 Bad request: {response.json()["message"]}.')
        elif response.status_code == 200:
            img_url = response.json()['imageUrl']
        else:
            self.update_status(doc_id, self.ERROR)
            raise Exception(f'{response.status_code}')

        return img_url

    def send_book(self, doc_id, content):
        if self.is_time_for_refreshing():
            self.refresh_token()

        self.refreshing.wait()
        json_content = {
            'json': json.dumps(content)
        }
        response = requests.post(f'{self.url}/doc-convert/{doc_id}/import', json=json_content, headers=self.headers)

        if response.status_code == 400:
            self.update_status(doc_id, self.ERROR)
            raise Exception(f'400 Bad request')
        elif response.status_code == 200:
            pass
        else:
            self.update_status(doc_id, self.ERROR)
            raise Exception(f'{response.status_code}')

    def update_status(self, doc_id, status):
        if self.is_time_for_refreshing():
            self.refresh_token()

        self.refreshing.wait()
        response = requests.patch(f'{self.url}/doc-convert/{doc_id}/status/{status}', headers=self.headers)

        if response.status_code == 400:
            raise Exception(f'400 Bad request')
        elif response.status_code == 200:
            pass
        else:
            raise Exception(f'{response.status_code}')