from random import shuffle

from marl_factory_grid.modules.items import constants as i
from marl_factory_grid.environment import constants as c

from marl_factory_grid.environment.groups.collection import Collection
from marl_factory_grid.environment.groups.objects import Objects
from marl_factory_grid.environment.groups.mixins import PositionMixin, IsBoundMixin, HasBoundMixin
from marl_factory_grid.environment.entity.agent import Agent
from marl_factory_grid.modules.items.entitites import Item, DropOffLocation


class Items(PositionMixin, Collection):
    _entity = Item

    @property
    def is_blocking_light(self):
        return False

    @property
    def can_collide(self):
        return False

    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)

    @staticmethod
    def trigger_item_spawn(state, n_items, spawn_frequency):
        if item_to_spawns := max(0, (n_items - len(state[i.ITEM]))):
            position_list = [x for x in state.entities.floorlist]
            shuffle(position_list)
            position_list = state.entities.floorlist[:item_to_spawns]
            state[i.ITEM].spawn(position_list)
            state.print(f'{item_to_spawns} new items have been spawned; next spawn in {spawn_frequency}')
            return len(position_list)
        else:
            state.print('No Items are spawning, limit is reached.')
            return 0


class Inventory(IsBoundMixin, Collection):
    _accepted_objects = Item

    @property
    def obs_tag(self):
        return self.name

    def __init__(self, agent: Agent, *args, **kwargs):
        super(Inventory, self).__init__(*args, **kwargs)
        self._collection = None
        self.bind(agent)

    def summarize_states(self, **kwargs):
        attr_dict = {key: val for key, val in self.__dict__.items() if not key.startswith('_') and key != 'data'}
        attr_dict.update(dict(items=[val.summarize_state(**kwargs) for key, val in self.items()]))
        attr_dict.update(dict(name=self.name, belongs_to=self._bound_entity.name))
        return attr_dict

    def pop(self):
        item_to_pop = self[0]
        self.delete_env_object(item_to_pop)
        return item_to_pop

    def set_collection(self, collection):
        self._collection = collection


class Inventories(HasBoundMixin, Objects):
    _entity = Inventory

    @property
    def var_can_move(self):
        return False

    def __init__(self, size: int, *args, **kwargs):
        super(Inventories, self).__init__(*args, **kwargs)
        self.size = size
        self._obs = None
        self._lazy_eval_transforms = []

    def spawn(self, agents):
        inventories = [self._entity(agent, self.size, )
                       for _, agent in enumerate(agents)]
        self.add_items(inventories)

    def idx_by_entity(self, entity):
        try:
            return next((idx for idx, inv in enumerate(self) if inv.belongs_to_entity(entity)))
        except StopIteration:
            return None

    def by_entity(self, entity):
        try:
            return next((inv for inv in self if inv.belongs_to_entity(entity)))
        except StopIteration:
            return None

    def summarize_states(self, **kwargs):
        return [val.summarize_states(**kwargs) for key, val in self.items()]

    @staticmethod
    def trigger_inventory_spawn(state):
        state[i.INVENTORY].spawn(state[c.AGENT])


class DropOffLocations(PositionMixin, Collection):
    _entity = DropOffLocation

    @property
    def is_blocking_light(self):
        return False

    @property
    def can_collide(self):
        return False

    def __init__(self, *args, **kwargs):
        super(DropOffLocations, self).__init__(*args, **kwargs)

    @staticmethod
    def trigger_drop_off_location_spawn(state, n_locations):
        empty_positions = state.entities.empty_positions()[:n_locations]
        do_entites = state[i.DROP_OFF]
        drop_offs = [DropOffLocation(pos) for pos in empty_positions]
        do_entites.add_items(drop_offs)