from urllib.parse import urlencode

import requests


class ApiException(Exception):
    def __init__(self, code, message):
        self.code = code
        self.message = message
        super().__init__()

    def __str__(self):
        return self.message


class BaseClient:
    gateway = None
    timeout = 10
    max_retries = 3

    def _build_url(self, interface, params, query=None, files=None):
        method, uri = interface

        query_params = query or {}
        if params and (method == 'get' or files):
            query_params.update(params)

        api_url = '{}/{}?{}'.format(self.gateway, uri, urlencode(query_params))
        return api_url

    def _get_headers(self):
        return None

    def call(self, interface, params=None, query=None, files=None, max_retries=max_retries, without_unpack=False):
        method, *_ = interface
        api_url = self._build_url(interface, params, query, files)
        headers = self._get_headers()
        try:
            if method == 'get':
                response = requests.request(method, api_url, headers=headers, timeout=self.timeout)
            else:
                response = requests.request(
                    method, api_url, headers=headers, timeout=self.timeout, json=params, files=files
                )
        except Exception as e:
            if max_retries > 0:
                return self.call(interface, params, files=files, max_retries=max_retries - 1)
            raise ApiException(504, "GATEWAY TIMEOUT") from e

        if without_unpack:
            return response

        try:
            data = self.unpack(response)
        except ApiException as e:
            raise e
        except Exception as e:
            print('BaseClient.call | interface | {}'.format(interface))
            print('BaseClient.call | api_url | {}'.format(api_url))
            raise ApiException(502, "BAD GATEWAY") from e

        return data

    @staticmethod
    def unpack(response):
        pass