import sys
sys.path.append("../wrappers")
from wrappers import modelverse as mv
import commons


class NodeAdd(object):
    def __init__(self):
        self._node_type = ""

    def execute(self, model, node_type, local, check_if_last=False):
        """
        Add a new node with type node_type to model model.
        If local is true, the node is only added to the model.
        If local is false, the node will be added to all models.
        """
        self._node_type = node_type
        if local:
            mv.transformation_execute_MANUAL("graph_ops/add_node", {"gm":model}, {"gm":model},
                                             callback=self._callback)
            # Local add can make a type mandatory and therefore break conformance
            if check_if_last:
                if commons.is_type_mandatory(node_type):
                    print("Type {} became mandatory, adding it to instance models ...".format(node_type))
                    # local add made type mandatory, so need to add to instance models
                    for im in commons.all_instance_models():
                        self.execute(im, node_type, local=True, check_if_last=False)

        else:
            for m in commons.all_models():
                self.execute(m, node_type, local=True)

    def _callback(self, model):
        node_id = mv.instantiate(model, "gm/Node")
        mv.attr_assign(model, node_id, "typeID", self._node_type)


class NodeDelete(object):
    def __init__(self):
        self._node = ""
        self._node_type = ""
        self._was_last = False

    def execute(self, model, node, local, check_if_last=False):
        self._node = node
        self._node_type = commons.get_node_type(model, node)

        if local:
            mv.transformation_execute_MANUAL("graph_ops/del_node", {"gm":model}, {"gm":model},
                                             callback=self._callback)
            if check_if_last:
                # check if we just deleted the last instance of the node in all example models
                # if yes, delete it in instance models as well to preserve their validity
                remaining_instances = 0
                for m in commons.all_example_models():
                    remaining_instances += len(commons.all_nodes_with_type(m, self._node_type))
                if remaining_instances == 0:
                    # it was indeed the last one, delete from instance models
                    self._was_last = True
                    for m in commons.all_instance_models():
                        nodes_to_delete = commons.all_nodes_with_type(m, self._node_type)
                        for node in nodes_to_delete:
                            self.execute(m, node, local=True)
        else:
            for m in commons.all_models():
                nodes_to_delete = commons.all_nodes_with_type(m, self._node_type)
                for node in nodes_to_delete:
                    self.execute(m, node, local=True)

    def was_last(self):
        return self._was_last

    def _callback(self, model):
        mv.delete_element(model, "gm/"+self._node)


class NodeRetype(object):
    def __init__(self):
        self._node = ""
        self._new_type = ""

    def execute(self, model, node, new_type, local):
        """
        Retype the node in model to new_type.
        If local is true, the change only affects the single node.
        If local is false, the change affects all nodes in all models.
        """
        self._node = node
        self._new_type = new_type
        if local:
            mv.transformation_execute_MANUAL("graph_ops/retype_node", {"gm":model}, {"gm":model},
                                             callback=self._callback)
        else:
            node_type = commons.get_node_type(model, node)
            for m in commons.all_models():
                for node in commons.all_nodes_with_type(m, node_type):
                    self.execute(m, node, new_type, local=True)

    def _callback(self, model):
        mv.attr_assign(model, "gm/"+self._node, "typeID", self._new_type)