import json
from os import path
from typing import Tuple, Type, Union, List

from openapi_core.validation.request.datatypes import OpenAPIRequest

from cic_eth.server.openapi.UWSGIOpenAPIRequest import UWSGIOpenAPIRequest
from openapi_core import create_spec
from openapi_core.validation.request.validators import RequestValidator
from openapi_spec_validator.schemas import read_yaml_file

spec_dict = read_yaml_file(path.join(path.dirname(
    __file__), './server.yaml'))
spec = create_spec(spec_dict)


def request(env, start_response) -> Tuple[Union[List[bytes], None], Type[OpenAPIRequest]]:
    oAPIRequest = UWSGIOpenAPIRequest(env)
    validator = RequestValidator(spec)
    result = validator.validate(oAPIRequest)

    if result.errors:
        json_data = json.dumps(list(map(lambda e: str(e), result.errors)))
        content = json_data.encode('utf-8')
        headers = []
        headers.append(('Content-Length', str(len(content))),)
        headers.append(('Access-Control-Allow-Origin', '*',))
        headers.append(('Content-Type', 'application/json',))
        start_response('400 Invalid Request', headers)
        return ([content], oAPIRequest)
    return (None, oAPIRequest)