from itertools import groupby
from typing import Type, Iterable, List, Dict

from pkg_resources import iter_entry_points
from httpie.plugins import AuthPlugin, FormatterPlugin, ConverterPlugin
from httpie.plugins.base import TransportPlugin, BasePlugin


ENTRY_POINT_NAMES = [
    'httpie.plugins.auth.v1',
    'httpie.plugins.formatter.v1',
    'httpie.plugins.converter.v1',
    'httpie.plugins.transport.v1',
]


class PluginManager:

    def __init__(self):
        self._plugins = []

    def __iter__(self):
        return iter(self._plugins)

    def register(self, *plugins: Type[BasePlugin]):
        for plugin in plugins:
            self._plugins.append(plugin)

    def unregister(self, plugin: BasePlugin):
        self._plugins.remove(plugin)

    def load_installed_plugins(self):
        for entry_point_name in ENTRY_POINT_NAMES:
            for entry_point in iter_entry_points(entry_point_name):
                plugin = entry_point.load()
                plugin.package_name = entry_point.dist.key
                self.register(entry_point.load())

    # Auth
    def get_auth_plugins(self) -> List[Type[AuthPlugin]]:
        return [plugin for plugin in self if issubclass(plugin, AuthPlugin)]

    def get_auth_plugin_mapping(self) -> Dict[str, Type[AuthPlugin]]:
        return {
            plugin.auth_type: plugin for plugin in self.get_auth_plugins()
        }

    def get_auth_plugin(self, auth_type: str) -> Type[AuthPlugin]:
        return self.get_auth_plugin_mapping()[auth_type]

    # Output processing
    def get_formatters(self) -> List[Type[FormatterPlugin]]:
        return [
            plugin for plugin in self
            if issubclass(plugin, FormatterPlugin)
        ]

    def get_formatters_grouped(self) -> Dict[str, List[Type[FormatterPlugin]]]:
        groups = {}
        for group_name, group in groupby(
                self.get_formatters(),
                key=lambda p: getattr(p, 'group_name', 'format')):
            groups[group_name] = list(group)
        return groups

    def get_converters(self) -> List[Type[ConverterPlugin]]:
        return [
            plugin for plugin in self
            if issubclass(plugin, ConverterPlugin)
        ]

    # Adapters
    def get_transport_plugins(self) -> List[Type[TransportPlugin]]:
        return [
            plugin for plugin in self
            if issubclass(plugin, TransportPlugin)
        ]