# Source code for pydsol.model.node

    """ """
    """
    Created on: 23-7-2021 16:00

    @author: IvS
    """
    import math
    import numpy as np
    import itertools

    from pydsol.model.basic_logger import get_module_logger
    from pydsol.model.entities import Entity

    logger = get_module_logger(__name__)

    __all__ = ["Node"]

    class Node(object):
        """This class defines a basic node for travelling in a discrete event simulation model. Input and output links
        are assigned by the link."""
        id_iter = itertools.count(1)

        def __init__(self, simulator, capacity=math.inf, **kwargs):
            """

            Parameters
            ----------
            simulator: Simulator object
                simulator of the model.
            capacity: int
                number of travellers that are simultaneously allowed on the node. Default is infinity.
            kwargs:
                kwargs are the keyword arguments that are used to expand the node class.
                *name: str
                    user-specified name for the node.
            """
            self.simulator = simulator
            self.capacity = capacity

            self.next = None

            self.id = next(self.id_iter)
            self.name = "{0} {1}".format(self.__class__.__name__, str(self.id))
            if "name" in kwargs:
                self.name = kwargs["name"]
            self.kwargs = kwargs

        def enter_input_node(self, entity: Entity, **kwargs):
            self.simulator.schedule_event_now(self, "exit_output_node", entity=entity)

        def exit_output_node(self, entity: Entity, **kwargs):
            """Exit the resource by selecting a link on which the entity should travel to the next destination by
            weighted choice.

            Parameters
            ----------
            entity: Entity
                the target on which a state change is scheduled.
            kwargs:
                kwargs are the keyword arguments that are used to expand the function.

            """
            # If there is a vehicle
            if "vehicle_type" in self.kwargs:
                if "vehicle_speed" in self.kwargs:
                    vehicle = self.kwargs["vehicle_type"](self.simulator, vehicle_speed=self.kwargs["vehicle_speed"])
                else:
                    vehicle = self.kwargs["vehicle_type"](self.simulator)
                vehicle.entities_on_vehicle.append(entity)
                logger.info("Time {0:.2f}: {1} loaded on {2} at {3}".format(self.simulator.simulator_time, entity.name,
                                                                            vehicle.name, self.name))
                entity = vehicle

            try:
                # Selection based on weights in links
                next_list = self.next if isinstance(self.next, list) else [self.next]
                weights = [link.selection_weight for link in next_list]
                link_by_weight = np.random.choice(np.array(next_list), p=weights / np.sum(weights))
                link_by_weight.enter_input_node(entity)
            except AttributeError:
                try:
                    if len(next_list) > 1:
                        next_process = np.random.choice(np.array(next_list))
                        next_process.enter_input_node(entity)
                    if len(next_list) == 1:
                        self.next.enter_input_node(entity)
                except AttributeError:
                    raise AttributeError("{0} has no next process assigned".format(self.name))