###############################################################################
#
# The MIT License (MIT)
#
# Copyright (c) Tavendo GmbH
#
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
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# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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from __future__ import absolute_import

import six

# The Python urlparse module currently does not contain the rs/rss
# schemes, so we add those dynamically (which is a hack of course).
# Since the urllib from six.moves does not seem to expose the stuff
# we monkey patch here, we do it manually.
#
# Important: if you change this stuff (you shouldn't), make sure
# _all_ our unit tests for WS URLs succeed
#
if not six.PY3:
    # Python 2
    import urlparse
else:
    # Python 3
    from urllib import parse as urlparse

wsschemes = ["rs", "rss"]
urlparse.uses_relative.extend(wsschemes)
urlparse.uses_netloc.extend(wsschemes)
urlparse.uses_params.extend(wsschemes)
urlparse.uses_query.extend(wsschemes)
urlparse.uses_fragment.extend(wsschemes)

__all__ = (
    "create_url",
    "parse_url",
)


def create_url(hostname, port=None, isSecure=False):
    """
    Create a RawSocket URL from components.

    :param hostname: RawSocket server hostname.
    :type hostname: str

    :param port: RawSocket service port or None (to select default
        ports 80/443 depending on isSecure).
    :type port: int

    :param isSecure: Set True for secure RawSocket ("rss" scheme).
    :type isSecure: bool

    :returns: str -- Constructed RawSocket URL.
    """
    if port is not None:
        netloc = "%s:%d" % (hostname, port)
    else:
        if isSecure:
            netloc = u"{}:443".format(hostname)
        else:
            netloc = u"{}:80".format(hostname)
    if isSecure:
        scheme = u"rss"
    else:
        scheme = u"rs"
    return u"{}://{}".format(scheme, netloc)


def parse_url(url):
    """
    Parses as RawSocket URL into it's components and returns a tuple (isSecure, host, port).

     - ``isSecure`` is a flag which is True for rss URLs.
     - ``host`` is the hostname or IP from the URL.
     - ``port`` is the port from the URL or standard port derived from
       scheme (rs = 80, rss = 443).

    :param url: A valid RawSocket URL, i.e. ``rs://localhost:9000``
    :type url: str

    :returns: tuple -- A tuple (isSecure, host, port)
    """
    parsed = urlparse.urlparse(url)

    if parsed.scheme not in ["rs", "rss"]:
        raise Exception("invalid RawSocket URL: protocol scheme '{}' is not for RawSocket".format(parsed.scheme))

    if not parsed.hostname or parsed.hostname == "":
        raise Exception("invalid RawSocket URL: missing hostname")

    if parsed.path is not None and parsed.path != "":
        raise Exception("invalid RawSocket URL: non-empty path '{}'".format(parsed.path))

    if parsed.query is not None and parsed.query != "":
        raise Exception("invalid RawSocket URL: non-empty query '{}'".format(parsed.query))

    if parsed.fragment is not None and parsed.fragment != "":
        raise Exception("invalid RawSocket URL: non-empty fragment '{}'".format(parsed.fragment))

    if parsed.port is None or parsed.port == "":
        if parsed.scheme == "rs":
            port = 80
        else:
            port = 443
    else:
        port = int(parsed.port)

    if port < 1 or port > 65535:
        raise Exception("invalid port {}".format(port))

    return parsed.scheme == "rss", parsed.hostname, port
