# coding: utf-8

{{>partial_header}}

import io
import json
import logging
import re

# python 2 and python 3 compatibility library
import six
from six.moves.urllib.parse import urlencode
import tornado
import tornado.gen
from tornado import httpclient
from urllib3.filepost import encode_multipart_formdata

logger = logging.getLogger(__name__)


class RESTResponse(io.IOBase):

    def __init__(self, resp):
        self.tornado_response = resp
        self.status = resp.code
        self.reason = resp.reason

        if resp.body:
            # In Python 3, the response body is utf-8 encoded bytes.
            if six.PY3:
                self.data = resp.body.decode('utf-8')
            else:
                self.data = resp.body
        else:
            self.data = None

    def getheaders(self):
        """Returns a CIMultiDictProxy of the response headers."""
        return self.tornado_response.headers

    def getheader(self, name, default=None):
        """Returns a given response header."""
        return self.tornado_response.headers.get(name, default)


class RESTClientObject(object):

    def __init__(self, configuration, pools_size=4, maxsize=4):
        # maxsize is number of requests to host that are allowed in parallel

        self.ca_certs = configuration.ssl_ca_cert
        self.client_key = configuration.key_file
        self.client_cert = configuration.cert_file

        self.proxy_port = self.proxy_host = None

        # https pool manager
        if configuration.proxy:
            self.proxy_port = 80
            self.proxy_host = configuration.proxy

        self.pool_manager = httpclient.AsyncHTTPClient()

    @tornado.gen.coroutine
    def request(self, method, url, query_params=None, headers=None, body=None,
                post_params=None, _preload_content=True,
                _request_timeout=None):
        """Execute Request

        :param method: http request method
        :param url: http request url
        :param query_params: query parameters in the url
        :param headers: http request headers
        :param body: request json body, for `application/json`
        :param post_params: request post parameters,
                            `application/x-www-form-urlencoded`
                            and `multipart/form-data`
        :param _preload_content: this is a non-applicable field for
                                 the AiohttpClient.
        :param _request_timeout: timeout setting for this request. If one
                                 number provided, it will be total request
                                 timeout. It can also be a pair (tuple) of
                                 (connection, read) timeouts.
        """
        method = method.upper()
        assert method in ['GET', 'HEAD', 'DELETE', 'POST', 'PUT',
                          'PATCH', 'OPTIONS']

        if post_params and body:
            raise ValueError(
                "body parameter cannot be used with post_params parameter."
            )

        request = httpclient.HTTPRequest(url)
        request.allow_nonstandard_methods = True
        request.ca_certs = self.ca_certs
        request.client_key = self.client_key
        request.client_cert = self.client_cert
        request.proxy_host = self.proxy_host
        request.proxy_port = self.proxy_port
        request.method = method
        if headers:
            request.headers = headers
        if 'Content-Type' not in headers:
            request.headers['Content-Type'] = 'application/json'
        request.request_timeout = _request_timeout or 5 * 60

        post_params = post_params or {}

        if query_params:
            request.url += '?' + urlencode(query_params)

        # For `POST`, `PUT`, `PATCH`, `OPTIONS`, `DELETE`
        if method in ['POST', 'PUT', 'PATCH', 'OPTIONS', 'DELETE']:
            if re.search('json', headers['Content-Type'], re.IGNORECASE):
                if body:
                    body = json.dumps(body)
                request.body = body
            elif headers['Content-Type'] == 'application/x-www-form-urlencoded':  # noqa: E501
                request.body = urlencode(post_params)
            elif headers['Content-Type'] == 'multipart/form-data':
                multipart = encode_multipart_formdata(post_params)
                request.body, headers['Content-Type'] = multipart
            # Pass a `bytes` parameter directly in the body to support
            # other content types than Json when `body` argument is provided
            # in serialized form
            elif isinstance(body, bytes):
                request.body = body
            else:
                # Cannot generate the request from given parameters
                msg = """Cannot prepare a request message for provided
                         arguments. Please check that your arguments match
                         declared content type."""
                raise ApiException(status=0, reason=msg)

        r = yield self.pool_manager.fetch(request, raise_error=False)

        if _preload_content:

            r = RESTResponse(r)

            # log response body
            logger.debug("response body: %s", r.data)

        if not 200 <= r.status <= 299:
            raise ApiException(http_resp=r)

        raise tornado.gen.Return(r)

    @tornado.gen.coroutine
    def GET(self, url, headers=None, query_params=None, _preload_content=True,
            _request_timeout=None):
        result = yield self.request("GET", url,
                                    headers=headers,
                                    _preload_content=_preload_content,
                                    _request_timeout=_request_timeout,
                                    query_params=query_params)
        raise tornado.gen.Return(result)

    @tornado.gen.coroutine
    def HEAD(self, url, headers=None, query_params=None, _preload_content=True,
             _request_timeout=None):
        result = yield self.request("HEAD", url,
                                    headers=headers,
                                    _preload_content=_preload_content,
                                    _request_timeout=_request_timeout,
                                    query_params=query_params)
        raise tornado.gen.Return(result)

    @tornado.gen.coroutine
    def OPTIONS(self, url, headers=None, query_params=None, post_params=None,
                body=None, _preload_content=True, _request_timeout=None):
        result = yield self.request("OPTIONS", url,
                                    headers=headers,
                                    query_params=query_params,
                                    post_params=post_params,
                                    _preload_content=_preload_content,
                                    _request_timeout=_request_timeout,
                                    body=body)
        raise tornado.gen.Return(result)

    @tornado.gen.coroutine
    def DELETE(self, url, headers=None, query_params=None, body=None,
               _preload_content=True, _request_timeout=None):
        result = yield self.request("DELETE", url,
                                    headers=headers,
                                    query_params=query_params,
                                    _preload_content=_preload_content,
                                    _request_timeout=_request_timeout,
                                    body=body)
        raise tornado.gen.Return(result)

    @tornado.gen.coroutine
    def POST(self, url, headers=None, query_params=None, post_params=None,
             body=None, _preload_content=True, _request_timeout=None):
        result = yield self.request("POST", url,
                                    headers=headers,
                                    query_params=query_params,
                                    post_params=post_params,
                                    _preload_content=_preload_content,
                                    _request_timeout=_request_timeout,
                                    body=body)
        raise tornado.gen.Return(result)

    @tornado.gen.coroutine
    def PUT(self, url, headers=None, query_params=None, post_params=None,
            body=None, _preload_content=True, _request_timeout=None):
        result = yield self.request("PUT", url,
                                    headers=headers,
                                    query_params=query_params,
                                    post_params=post_params,
                                    _preload_content=_preload_content,
                                    _request_timeout=_request_timeout,
                                    body=body)
        raise tornado.gen.Return(result)

    @tornado.gen.coroutine
    def PATCH(self, url, headers=None, query_params=None, post_params=None,
              body=None, _preload_content=True, _request_timeout=None):
        result = yield self.request("PATCH", url,
                                    headers=headers,
                                    query_params=query_params,
                                    post_params=post_params,
                                    _preload_content=_preload_content,
                                    _request_timeout=_request_timeout,
                                    body=body)
        raise tornado.gen.Return(result)


class ApiException(Exception):

    def __init__(self, status=None, reason=None, http_resp=None):
        if http_resp:
            self.status = http_resp.status
            self.reason = http_resp.reason
            self.body = http_resp.data
            self.headers = http_resp.getheaders()
        else:
            self.status = status
            self.reason = reason
            self.body = None
            self.headers = None

    def __str__(self):
        """Custom error messages for exception"""
        error_message = "({0})\nReason: {1}\n".format(
            self.status, self.reason)
        if self.headers:
            error_message += "HTTP response headers: {0}\n".format(
                self.headers)

        if self.body:
            error_message += "HTTP response body: {0}\n".format(self.body)

        return error_message
