# Licensed to the Apache Software Foundation (ASF) under one or more
# contributor license agreements.  See the NOTICE file distributed with
# this work for additional information regarding copyright ownership.
# The ASF licenses this file to You under the Apache License, Version 2.0
# (the "License"); you may not use this file except in compliance with
# the License.  You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

__all__ = [
    'BaseHTTPError',
    'RateLimitReachedError',

    'exception_from_message'
]


class BaseHTTPError(Exception):

    """
    The base exception class for all HTTP related exceptions.
    """

    def __init__(self, code, message, headers=None):
        self.code = code
        self.message = message
        self.headers = headers
        # preserve old exception behavior for tests that
        # look for e.args[0]
        super(BaseHTTPError, self).__init__(message)

    def __str__(self):
        return self.message

    def __repr__(self):
        return '<{name} ({code}, "{message}", headers={headers})>'.format(
            name=self.__class__.__name__,
            code=self.code,
            message=self.message,
            headers=self.headers)


class RateLimitReachedError(BaseHTTPError):
    """
    HTTP 429 - Rate limit: you've sent too many requests for this time period.
    """
    code = 429
    message = 'Rate limit exceeded'
    retry_after = None

    def __init__(self, code, message, headers=None):
        if headers is not None:
            self.retry_after = int(headers.get('retry_after', None))
        super(RateLimitReachedError, self).__init__(
            code if code is not None else self.code,
            message if message is not None else self.message,
            headers=headers)


_error_classes = [RateLimitReachedError]
_code_map = dict((c.code, c) for c in _error_classes)


def exception_from_message(code, message, headers=None):
    """
    Return an instance of :class:`BaseHTTPError` or
    subclass based on response code or error message.

    Usage:

    >>>    raise exception_from_message(
    >>>        code=response.status,
    >>>        message=response.parse_error())
    """
    cls = _code_map.get(code, BaseHTTPError)
    return cls(code, message, headers=headers)
