# vim: set filencoding=utf8
"""
Remember The Milk Authentication

@author: Mike Crute (mcrute@ag.com)
@organization: American Greetings Interactive
@date: February 03, 2010
"""

import json
import urllib
from logging import getLogger
from hashlib import md5
from milkman import API_URL


logger = getLogger('rtmapi')


class APIPerms(object):

    READ = "read"
    WRITE = "write"
    DELETE = "delete"


def flatten_sorted_dict(in_dict):
    items = sorted(in_dict.items())
    flat_items = [''.join(item) for item in items]
    return ''.join(flat_items)


class APIError(Exception):
    pass


class Request(object):

    def __init__(self, api_key, secret, service='rest'):
        self.service = service
        self.secret = secret
        self.params = {
                'format': 'json',
                'api_key': api_key,
                }

    @classmethod
    def get_factory(cls, api_key, secret):
        return lambda: cls(api_key, secret)

    @property
    def url(self):
        self._sign_request()
        params = urllib.urlencode(self.params)
        return '{0}/{1}?{2}'.format(API_URL, self.service, params)

    def _sign_request(self):
        param_string = self.secret
        param_string += flatten_sorted_dict(self.params)
        self.params['api_sig'] = md5(param_string).hexdigest()

    def __setitem__(self, key, value):
        self.params[key] = value

    def __getitem__(self, key):
        return self.params[key]

    def _parse_json_data(self, data):
        body = data['rsp']
        status = body['stat']

        if status == 'fail':
            error = APIError(body['err']['msg'])
            error.code = int(body['err']['code'])
            raise error

        del body['stat']

        return body

    def execute(self):
        data = urllib.urlopen(self.url)
        raw_data = data.read()
        json_data = json.loads(raw_data)

        return self._parse_json_data(json_data)


class Authenticator(object):

    def __init__(self, request_factory):
        self.request_factory = request_factory
        self.token = None

    def authenticate(self, token=None):
        if token:
            self.token = token

        if not self.check_token(self.token):
            raw_input("Please visit: {0}".format(self.get_auth_url()))
            self.token = self.get_token()

    def get_auth_url(self):
        req = self.request_factory()
        req.service = 'auth'
        req['perms'] = APIPerms.DELETE
        req['frob'] = self._get_frob()

        return req.url

    def _get_frob(self):
        req = self.request_factory()
        req['method'] = 'rtm.auth.getFrob'
        self.frob = req.execute()['frob']

        return self.frob

    def get_token(self):
        req = self.request_factory()
        req['method'] = 'rtm.auth.getToken'
        req['frob'] = self.frob

        print req.execute()

    def check_token(self, token):
        if not token:
            return False

        req = self.request_factory()
        req['method'] = 'rtm.auth.checkToken'
        req['token'] = token

        try:
            req.execute()
            return True
        except APIError, err:
            if err.code == 98:
                return False
            raise


class APIConnection(object):

    def __init__(self, api_key, secret):
        self.request_factory = Request.get_factory(api_key, secret)
        self.auth = Authenticator(self.request_factory)

    def authenticate(self, token=None):
        self.auth.authenticate(token)
        print self.auth.token

    def get_lists(self):
        req = self.request_factory()
        req['method'] = 'rtm.lists.getList'
        req['auth_token'] = self.auth.token

        print req.execute()



if __name__ == '__main__':
    API_KEY = "38816a01a7937588081d33ea74b6f5ee"
    SECRET = "d4caed275cf9a63e"

    TOKEN = "54f3378cb114e6cc330e1c2fd34a11e96e2a26c5"

    api = APIConnection(API_KEY, SECRET)
    api.authenticate(TOKEN)
    api.get_lists()