Hook Manager

########################################################################################################################
#    File: hooks.py
#  Author: Dan Huckson, https://github.com/unodan
#    Date: 2019-12-01
########################################################################################################################


class _HookManager:
    def __init__(self):
        self._hooks = {}
        self._events = {}

    @property
    def hooks(self):
        return self._hooks

    @property
    def events(self):
        return self._events

    def add_hook(self, target, hook, callback):

        if target not in self._hooks:
            self._hooks[target] = {}

        if hook not in self._hooks[target]:
            self._hooks[target][hook] = {}

        if callback not in self._hooks[target][hook].values():
            key = target + '/' + hook + '/' + str(callback).strip('>').split(' ')[-1]
            self._hooks[target][hook][key] = callback
            return True

        return False

    def remove(self, target, hook, callback):
        key = None
        for _key, _callback in self._hooks[target][hook].items():
            if callback == _callback:
                key = _key
                break

        if key:

            del self._hooks[target][hook][key]
            if not self._hooks[target][hook]:
                del self._hooks[target][hook]
            return True

        return False

    def get_hook(self, target, hook):
        if hook in self._hooks[target]:
            return self._hooks[target][hook]

        return {}

    def get_hooks(self, target=None):
        if not target:
            return self._hooks

        if target in self._hooks:
            return self._hooks[target]

        return {}

    def event(self, target, hook):
        hooks = self.get_hooks(target)
        triggers = self.get_events(target)

        if hook in triggers and hook in hooks:
            for callback in hooks[hook].values():
                callback(self)

    def add_event(self, target, hook, callback):
        if target not in self._events:
            self._events[target] = {}

        if hook not in self._events[target]:
            self._events[target][hook] = {}

        if callback not in self._events[target][hook].values():
            key = target + '/' + hook + '/' + str(callback).strip('>').split(' ')[-1]
            self._events[target][hook][key] = callback
            return True

        return False

    def get_events(self, target=None):
        if not target:
            return self._events

        if target in self._events:
            return self._events[target]

        return {}


class HookManager:
    instance = None

    def __new__(cls, **kwargs):
        if not cls.instance:
            cls.instance = super(HookManager, cls).__new__(cls)
            cls.instance.hook_manager = _HookManager()

        return cls.instance.hook_manager


hook_manager = HookManager()