#!/usr/bin/env python

"""client.py - HTTP client APIs."""

__license__ = """
Copyright (c) 2001-2004 Mark Nottingham <mnot@pobox.com>

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
"""

__version__ = "0.11"

# TODO:
# Dict
# - trap socket errors (e.g., no address, timeout, connect, etc.)
# - phase out httplib
# - HTTP persistent connections / connection management
# - caching
# - authentication; userinfo as property dict, raise error
# - redirection handling
# - content negotiation; prefs as properties
# - better HTTP header handling
# - delta encoding
# - stricter HTTP conformance, corner cases
# - SSL / TLS
# - define and use URI object
# - allow access to body as a file-like object
# - allow dispatch to other URI schemes?
# - WebDAV methods: .copy() .move() .lock() PROPFIND? MKCOL?
# - HTTP Extension framework support?
# - set user-agent w/ property
# - cookies w/ property dict
# - consider other dictionary methods (see UserDict.UserDict)
# - allow instantiation to specify DNS forwarder

from httplib import HTTP
from urlparse import urlparse
from message import Request, Response
import status


class Dict:
    """Dictionary of Representations."""
    def __getitem__(self, key):
        "GET"
        request = Request()
        request.uri = key
        request.method = "GET"
        response = dereference(request)
        return response.representation
        
    def __setitem__(self, key, item):
        "PUT"
        request = Request(representation=item)
        request.uri = key
        request.method = "PUT"
        response = dereference(request)
        
    def __delitem__(self, key):
        "DELETE"
        request = Request()
        request.uri = key
        request.method = "DELETE"
        response = dereference(request)
        
    def __call__(self, uri, representation):
        "POST"
        request = Request(representation=representation)
        request.uri = uri
        request.method = "POST"
        response = dereference(request)
        return response.representation


def dereference(request):
    """Given a Request instance, dereference the .uri and return a Response instance."""
    response = Response()
    h = HTTP(urlparse(request.uri)[1])  ### split out port, userinfo
    h.putrequest(request.method, request.uri)
    if request.representation.body != None:
        for field_name, field_value in request.representation.headers.items():
            if field_name.lower() == "content-length": continue
            h.putheader(field_name, field_value)
        h.putheader('content-length', str(len(request.representation.body)))
    h.endheaders()
    if request.representation.body != None:
        h.send(request.representation.body)
    status_code, status_phrase, headers = h.getreply()
    response = status.lookup.get(status_code, None)
    if response is None:
        response = status.Status()
        response.status_code = status_code
        response.status_phrase = status_phrase
    else:
        response = response()
    response.representation.headers = headers.dict  ### split entity and message hdrs
    if isinstance(response, (status.ClientError, status.ServerError)):
        raise response      ### more fine-grained
    response.representation.body = h.getfile().read()
    return response