########################################################################################################################
#    File: base.py
#  Author: Dan Huckson, https://github.com/unodan
#    Date: 2018-11-10
########################################################################################################################

class Hookman(object):
    instance = None

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

        return cls.instance.manager


class _HookManager(object):
    def __init__(self):
        self.hooks = {}

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

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

        key = target + '/' + hook + '/' + str(len(self.hooks[target][hook]))
        self.hooks[target][hook].update({key: callback})

    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]

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

    def get_hooks(self, target):
        if target in self.hooks:
            return self.hooks[target]