# -*- coding: utf-8 -*-

"""
requests.models
~~~~~~~~~~~~~~~

This module contains the primary objects that power Requests.
"""

import datetime
import sys

# Import encoding now, to avoid implicit import later.
# Implicit import within threads may cause LookupError when standard library is in a ZIP,
# such as in Embedded Python. See https://github.com/requests/requests/issues/3578.
import encodings.idna

from urllib3.fields import RequestField
from urllib3.filepost import encode_multipart_formdata
from urllib3.util import parse_url
from urllib3.exceptions import (
    DecodeError, ReadTimeoutError, ProtocolError, LocationParseError)

from io import UnsupportedOperation
from .hooks import default_hooks
from .structures import CaseInsensitiveDict

from .auth import HTTPBasicAuth
from .cookies import cookiejar_from_dict, get_cookie_header, _copy_cookie_jar
from .exceptions import (
    HTTPError, MissingSchema, InvalidURL, ChunkedEncodingError,
    ContentDecodingError, ConnectionError, StreamConsumedError)
from ._internal_utils import to_native_string, unicode_is_ascii
from .utils import (
    guess_filename, get_auth_from_url, requote_uri,
    stream_decode_response_unicode, to_key_val_list, parse_header_links,
    iter_slices, guess_json_utf, super_len, check_header_validity)
from .compat import (
    Callable, Mapping,
    cookielib, urlunparse, urlsplit, urlencode, str, bytes,
    is_py2, chardet, builtin_str, basestring)
from .compat import json as complexjson
from .status_codes import codes

#: The set of HTTP status codes that indicate an automatically
#: processable redirect.
REDIRECT_STATI = (
    codes.moved,               # 301
    codes.found,               # 302
    codes.other,               # 303
    codes.temporary_redirect,  # 307
    codes.permanent_redirect,  # 308
)

DEFAULT_REDIRECT_LIMIT = 30
CONTENT_CHUNK_SIZE = 10 * 1024
ITER_CHUNK_SIZE = 512


class RequestEncodingMixin(object):
    @property
    def path_url(self):
        """Build the path URL to use."""

        url = []

        p = urlsplit(self.url)

        path = p.path
        if not path:
            path = '/'

        url.append(path)

        query = p.query
        if query:
            url.append('?')
            url.append(query)

        return ''.join(url)

    @staticmethod
    def _encode_params(data):
        """Encode parameters in a piece of data.

        Will successfully encode parameters when passed as a dict or a list of
        2-tuples. Order is retained if data is a list of 2-tuples but arbitrary
        if parameters are supplied as a dict.
        """

        if isinstance(data, (str, bytes)):
            return data
        elif hasattr(data, 'read'):
            return data
        elif hasattr(data, '__iter__'):
            result = []
            for k, vs in to_key_val_list(data):
                if isinstance(vs, basestring) or not hasattr(vs, '__iter__'):
                    vs = [vs]
                for v in vs:
                    if v is not None:
                        result.append(
                            (k.encode('utf-8') if isinstance(k, str) else k,
                             v.encode('utf-8') if isinstance(v, str) else v))
            return urlencode(result, doseq=True)
        else:
            return data

    @staticmethod
    def _encode_files(files, data):
        """Build the body for a multipart/form-data request.

        Will successfully encode files when passed as a dict or a list of
        tuples. Order is retained if data is a list of tuples but arbitrary
        if parameters are supplied as a dict.
        The tuples may be 2-tuples (filename, fileobj), 3-tuples (filename, fileobj, contentype)
        or 4-tuples (filename, fileobj, contentype, custom_headers).
        """
        if (not files):
            raise ValueError("Files must be provided.")
        elif isinstance(data, basestring):
            raise ValueError("Data must not be a string.")

        new_fields = []
        fields = to_key_val_list(data or {})
        files = to_key_val_list(files or {})

        for field, val in fields:
            if isinstance(val, basestring) or not hasattr(val, '__iter__'):
                val = [val]
            for v in val:
                if v is not None:
                    # Don't call str() on bytestrings: in Py3 it all goes wrong.
                    if not isinstance(v, bytes):
                        v = str(v)

                    new_fields.append(
                        (field.decode('utf-8') if isinstance(field, bytes) else field,
                         v.encode('utf-8') if isinstance(v, str) else v))

        for (k, v) in files:
            # support for explicit filename
            ft = None
            fh = None
            if isinstance(v, (tuple, list)):
                if len(v) == 2:
                    fn, fp = v
                elif len(v) == 3:
                    fn, fp, ft = v
                else:
                    fn, fp, ft, fh = v
            else:
                fn = guess_filename(v) or k
                fp = v

            if isinstance(fp, (str, bytes, bytearray)):
                fdata = fp
            elif hasattr(fp, 'read'):
                fdata = fp.read()
            elif fp is None:
                continue
            else:
                fdata = fp

            rf = RequestField(name=k, data=fdata, filename=fn, headers=fh)
            rf.make_multipart(content_type=ft)
            new_fields.append(rf)

        body, content_type = encode_multipart_formdata(new_fields)

        return body, content_type


class RequestHooksMixin(object):
    def register_hook(self, event, hook):
        """Properly register a hook."""

        if event not in self.hooks:
            raise ValueError('Unsupported event specified, with event name "%s"' % (event))

        if isinstance(hook, Callable):
            self.hooks[event].append(hook)
        elif hasattr(hook, '__iter__'):
            self.hooks[event].extend(h for h in hook if isinstance(h, Callable))

    def deregister_hook(self, event, hook):
        """Deregister a previously registered hook.
        Returns True if the hook existed, False if not.
        """

        try:
            self.hooks[event].remove(hook)
            return True
        except ValueError:
            return False


class Request(RequestHooksMixin):
    """A user-created :class:`Request <Request>` object.

    Used to prepare a :class:`PreparedRequest <PreparedRequest>`, which is sent to the server.

    :param method: HTTP method to use.
    :param url: URL to send.
    :param headers: dictionary of headers to send.
    :param files: dictionary of {filename: fileobject} files to multipart upload.
    :param data: the body to attach to the request. If a dictionary or
        list of tuples ``[(key, value)]`` is provided, form-encoding will
        take place.
    :param json: json for the body to attach to the request (if files or data is not specified).
    :param params: URL parameters to append to the URL. If a dictionary or
        list of tuples ``[(key, value)]`` is provided, form-encoding will
        take place.
    :param auth: Auth handler or (user, pass) tuple.
    :param cookies: dictionary or CookieJar of cookies to attach to this request.
    :param hooks: dictionary of callback hooks, for internal usage.

    Usage::

      >>> import requests
      >>> req = requests.Request('GET', 'https://httpbin.org/get')
      >>> req.prepare()
      <PreparedRequest [GET]>
    """

    def __init__(self,
            method=None, url=None, headers=None, files=None, data=None,
            params=None, auth=None, cookies=None, hooks=None, json=None):

        # Default empty dicts for dict params.
        data = [] if data is None else data
        files = [] if files is None else files
        headers = {} if headers is None else headers
        params = {} if params is None else params
        hooks = {} if hooks is None else hooks

        self.hooks = default_hooks()
        for (k, v) in list(hooks.items()):
            self.register_hook(event=k, hook=v)

        self.method = method
        self.url = url
        self.headers = headers
        self.files = files
        self.data = data
        self.json = json
        self.params = params
        self.auth = auth
        self.cookies = cookies

    def __repr__(self):
        return '<Request [%s]>' % (self.method)

    def prepare(self):
        """Constructs a :class:`PreparedRequest <PreparedRequest>` for transmission and returns it."""
        p = PreparedRequest()
        p.prepare(
            method=self.method,
            url=self.url,
            headers=self.headers,
            files=self.files,
            data=self.data,
            json=self.json,
            params=self.params,
            auth=self.auth,
            cookies=self.cookies,
            hooks=self.hooks,
        )
        return p


class PreparedRequest(RequestEncodingMixin, RequestHooksMixin):
    """The fully mutable :class:`PreparedRequest <PreparedRequest>` object,
    containing the exact bytes that will be sent to the server.

    Generated from either a :class:`Request <Request>` object or manually.

    Usage::

      >>> import requests
      >>> req = requests.Request('GET', 'https://httpbin.org/get')
      >>> r = req.prepare()
      <PreparedRequest [GET]>

      >>> s = requests.Session()
      >>> s.send(r)
      <Response [200]>
    """

    def __init__(self):
        #: HTTP verb to send to the server.
        self.method = None
        #: HTTP URL to send the request to.
        self.url = None
        #: dictionary of HTTP headers.
        self.headers = None
        # The `CookieJar` used to create the Cookie header will be stored here
        # after prepare_cookies is called
        self._cookies = None
        #: request body to send to the server.
        self.body = None
        #: dictionary of callback hooks, for internal usage.
        self.hooks = default_hooks()
        #: integer denoting starting position of a readable file-like body.
        self._body_position = None

    def prepare(self,
            method=None, url=None, headers=None, files=None, data=None,
            params=None, auth=None, cookies=None, hooks=None, json=None):
        """Prepares the entire request with the given parameters."""

        self.prepare_method(method)
        self.prepare_url(url, params)
        self.prepare_headers(headers)
        self.prepare_cookies(cookies)
        self.prepare_body(data, files, json)
        self.prepare_auth(auth, url)

        # Note that prepare_auth must be last to enable authentication schemes
        # such as OAuth to work on a fully prepared request.

        # This MUST go after prepare_auth. Authenticators could add a hook
        self.prepare_hooks(hooks)

    def __repr__(self):
        return '<PreparedRequest [%s]>' % (self.method)

    def copy(self):
        p = PreparedRequest()
        p.method = self.method
        p.url = self.url
        p.headers = self.headers.copy() if self.headers is not None else None
        p._cookies = _copy_cookie_jar(self._cookies)
        p.body = self.body
        p.hooks = self.hooks
        p._body_position = self._body_position
        return p

    def prepare_method(self, method):
        """Prepares the given HTTP method."""
        self.method = method
        if self.method is not None:
            self.method = to_native_string(self.method.upper())

    @staticmethod