# Copyright 2012 Vincent Jacques
# vincent@vincent-jacques.net

# This file is part of PyGithub. http://vincent-jacques.net/PyGithub

# PyGithub is free software: you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License
# as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

# PyGithub is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License for more details.

# You should have received a copy of the GNU Lesser General Public License along with PyGithub.  If not, see <http://www.gnu.org/licenses/>.

import logging
import httplib
import base64
import urllib
import urlparse
import sys

atLeastPython26 = sys.hexversion >= 0x02060000

if atLeastPython26:
    import json
else:  # pragma no cover
    import simplejson as json  # pragma no cover

import GithubException
import Logging


class Requester:
    __httpConnectionClass = httplib.HTTPConnection
    __httpsConnectionClass = httplib.HTTPSConnection

    @classmethod
    def injectConnectionClasses(cls, httpConnectionClass, httpsConnectionClass):
        cls.__httpConnectionClass = httpConnectionClass
        cls.__httpsConnectionClass = httpsConnectionClass

    def __init__(self, login_or_token, password, base_url, timeout):
        if password is not None:
            login = login_or_token
            self.__authorizationHeader = "Basic " + base64.b64encode(login + ":" + password).replace('\n', '')
        elif login_or_token is not None:
            token = login_or_token
            self.__authorizationHeader = "token " + token
        else:
            self.__authorizationHeader = None

        self.__base_url = base_url
        o = urlparse.urlparse(base_url)
        self.__hostname = o.hostname
        self.__port = o.port
        self.__prefix = o.path
        self.__timeout = timeout
        self.__scheme = o.scheme
        if o.scheme == "https":
            self.__connectionClass = self.__httpsConnectionClass
        elif o.scheme == "http":
            self.__connectionClass = self.__httpConnectionClass
        else:
            assert(False)  # pragma no cover
        self.rate_limiting = (5000, 5000)

    def requestAndCheck(self, verb, url, parameters, input):
        status, headers, output = self.requestRaw(verb, url, parameters, input)
        output = self.__structuredFromJson(output)
        if status >= 400:
            raise GithubException.GithubException(status, output)
        return headers, output

    def requestRaw(self, verb, url, parameters, input):
        assert verb in ["HEAD", "GET", "POST", "PATCH", "PUT", "DELETE"]

        # URLs generated locally will be relative to __base_url
        # URLs returned from the server will start with __base_url
        if url.startswith("/"):
            url = self.__prefix + url
        else:
            o = urlparse.urlparse(url)
            assert o.scheme == self.__scheme or o.scheme == "https" and self.__scheme == "http"  # Issue #80
            assert o.hostname == self.__hostname
            assert o.path.startswith(self.__prefix)
            assert o.port == self.__port
            url = o.path
            if o.query != "":
                url += "?" + o.query

        headers = dict()
        if input is not None:
            headers["Content-Type"] = "application/json"
        if self.__authorizationHeader is not None:
            headers["Authorization"] = self.__authorizationHeader

        if atLeastPython26:
            cnx = self.__connectionClass(host=self.__hostname, port=self.__port, strict=True, timeout=self.__timeout)
        else:  # pragma no cover
            cnx = self.__connectionClass(host=self.__hostname, port=self.__port, strict=True)  # pragma no cover
        cnx.request(
            verb,
            self.__completeUrl(url, parameters),
            json.dumps(input),
            headers
        )
        response = cnx.getresponse()

        status = response.status
        headers = dict(response.getheaders())
        output = response.read()

        cnx.close()

        if "x-ratelimit-remaining" in headers and "x-ratelimit-limit" in headers:
            self.rate_limiting = (int(headers["x-ratelimit-remaining"]), int(headers["x-ratelimit-limit"]))

        logger = Logging.get_logger()
        if logger.isEnabledFor(logging.DEBUG):
            logger.debug(' '.join(map(str, [verb, self.__base_url + url, parameters, input, "==>", status, str(headers), str(output)])))
        return status, headers, output

    def __completeUrl(self, url, parameters):
        if parameters is None or len(parameters) == 0:
            return url
        else:
            return url + "?" + urllib.urlencode(parameters)

    def __structuredFromJson(self, data):
        if len(data) == 0:
            return None
        else:
            return json.loads(data)