from livestreamer.options import Options

class Plugin(object):
    """
        A plugin can retrieve stream information from the *url* specified.
    """

    options = Options()

    def __init__(self, url):
        self.url = url
        self.logger = self.session.logger.new_module("plugin." + self.module)

    @classmethod
    def can_handle_url(cls, url):
       raise NotImplementedError

    @classmethod
    def set_option(cls, key, value):
        cls.options.set(key, value)

    @classmethod
    def get_option(cls, key):
        return cls.options.get(key)

    def get_streams(self):
        """
            Retrieves and returns a :class:`dict` containing the streams.

            The key is the name of the stream, most commonly the quality.
            The value is a :class:`Stream` object.

            The stream with key *best* is a reference to the stream most likely
            to be of highest quality.
        """

        ranking = ["iphonelow", "iphonehigh", "240p", "320k", "360p", "SQTest", "SQ", "850k",
                   "480p", "HQTest", "HQ", "1400k", "720p", "2400k", "hd", "1080p", "live"]
        streams = self._get_streams()
        for rank in reversed(ranking):
            if rank in streams:
                streams["best"] = streams[rank]
                break

        return streams

    def _get_streams(self):
        raise NotImplementedError

class PluginError(Exception):
    pass

class NoStreamsError(PluginError):
    def __init__(self, url):
        PluginError.__init__(self, ("No streams found on this URL: {0}").format(url))

class NoPluginError(PluginError):
    pass

__all__ = ["Plugin", "PluginError", "NoStreamsError", "NoPluginError"]