from StringIO import StringIO
from django.conf import settings
from django.core.handlers.wsgi import WSGIRequest
from django.http import SimpleCookie
from django.test.client import (FakePayload, MULTIPART_CONTENT, encode_multipart, 
    BOUNDARY, CONTENT_TYPE_RE)
from django.utils.encoding import smart_str
from urllib import urlencode
from urlparse import urlparse
import urllib


class RequestFactory(object):
    """
    Class that lets you create mock Request objects for use in testing.

    Usage:

    rf = RequestFactory()
    get_request = rf.get('/hello/')
    post_request = rf.post('/submit/', {'foo': 'bar'})

    Once you have a request object you can pass it to any view function,
    just as if that view had been hooked up using a URLconf.
    """
    def __init__(self, **defaults):
        self.defaults = defaults
        self.cookies = SimpleCookie()
        self.errors = StringIO()

    def _base_environ(self, **request):
        """
        The base environment for a request.
        """
        environ = {
            'HTTP_COOKIE':       self.cookies.output(header='', sep='; '),
            'PATH_INFO':         '/',
            'QUERY_STRING':      '',
            'REMOTE_ADDR':       '127.0.0.1',
            'REQUEST_METHOD':    'GET',
            'SCRIPT_NAME':       '',
            'SERVER_NAME':       'testserver',
            'SERVER_PORT':       '80',
            'SERVER_PROTOCOL':   'HTTP/1.1',
            'wsgi.version':      (1,0),
            'wsgi.url_scheme':   'http',
            'wsgi.errors':       self.errors,
            'wsgi.multiprocess': True,
            'wsgi.multithread':  False,
            'wsgi.run_once':     False,
        }
        environ.update(self.defaults)
        environ.update(request)
        return environ

    def request(self, **request):
        "Construct a generic request object."
        req = WSGIRequest(self._base_environ(**request))
        req.session = {}
        return req

    def _get_path(self, parsed):
        # If there are parameters, add them
        if parsed[3]:
            return urllib.unquote(parsed[2] + ";" + parsed[3])
        else:
            return urllib.unquote(parsed[2])

    def get(self, path, data={}, **extra):
        "Construct a GET request"

        parsed = urlparse(path)
        r = {
            'CONTENT_TYPE':    'text/html; charset=utf-8',
            'PATH_INFO':       self._get_path(parsed),
            'QUERY_STRING':    urlencode(data, doseq=True) or parsed[4],
            'REQUEST_METHOD': 'GET',
            'wsgi.input':      FakePayload('')
        }
        r.update(extra)
        return self.request(**r)

    def post(self, path, data={}, content_type=MULTIPART_CONTENT,
             **extra):
        "Construct a POST request."

        if content_type is MULTIPART_CONTENT:
            post_data = encode_multipart(BOUNDARY, data)
        else:
            # Encode the content so that the byte representation is correct.
            match = CONTENT_TYPE_RE.match(content_type)
            if match:
                charset = match.group(1)
            else:
                charset = settings.DEFAULT_CHARSET
            post_data = smart_str(data, encoding=charset)

        parsed = urlparse(path)
        r = {
            'CONTENT_LENGTH': len(post_data),
            'CONTENT_TYPE':   content_type,
            'PATH_INFO':      self._get_path(parsed),
            'QUERY_STRING':   parsed[4],
            'REQUEST_METHOD': 'POST',
            'wsgi.input':     FakePayload(post_data),
        }
        r.update(extra)
        return self.request(**r)

    def head(self, path, data={}, **extra):
        "Construct a HEAD request."

        parsed = urlparse(path)
        r = {
            'CONTENT_TYPE':    'text/html; charset=utf-8',
            'PATH_INFO':       self._get_path(parsed),
            'QUERY_STRING':    urlencode(data, doseq=True) or parsed[4],
            'REQUEST_METHOD': 'HEAD',
            'wsgi.input':      FakePayload('')
        }
        r.update(extra)
        return self.request(**r)

    def options(self, path, data={}, **extra):
        "Constrict an OPTIONS request"

        parsed = urlparse(path)
        r = {
            'PATH_INFO':       self._get_path(parsed),
            'QUERY_STRING':    urlencode(data, doseq=True) or parsed[4],
            'REQUEST_METHOD': 'OPTIONS',
            'wsgi.input':      FakePayload('')
        }
        r.update(extra)
        return self.request(**r)

    def put(self, path, data={}, content_type=MULTIPART_CONTENT,
            **extra):
        "Construct a PUT request."

        if content_type is MULTIPART_CONTENT:
            post_data = encode_multipart(BOUNDARY, data)
        else:
            post_data = data

        # Make `data` into a querystring only if it's not already a string. If
        # it is a string, we'll assume that the caller has already encoded it.
        query_string = None
        if not isinstance(data, basestring):
            query_string = urlencode(data, doseq=True)

        parsed = urlparse(path)
        r = {
            'CONTENT_LENGTH': len(post_data),
            'CONTENT_TYPE':   content_type,
            'PATH_INFO':      self._get_path(parsed),
            'QUERY_STRING':   query_string or parsed[4],
            'REQUEST_METHOD': 'PUT',
            'wsgi.input':     FakePayload(post_data),
        }
        r.update(extra)
        return self.request(**r)

    def delete(self, path, data={}, **extra):
        "Construct a DELETE request."

        parsed = urlparse(path)
        r = {
            'PATH_INFO':       self._get_path(parsed),
            'QUERY_STRING':    urlencode(data, doseq=True) or parsed[4],
            'REQUEST_METHOD': 'DELETE',
            'wsgi.input':      FakePayload('')
        }
        r.update(extra)
        return self.request(**r)