"""
 Copyright (c) 2018-2019 Intel Corporation

 Licensed under the Apache License, Version 2.0 (the "License");
 you may not use this file except in compliance with the License.
 You may obtain a copy of the License at

      http://www.apache.org/licenses/LICENSE-2.0

 Unless required by applicable law or agreed to in writing, software
 distributed under the License is distributed on an "AS IS" BASIS,
 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 See the License for the specific language governing permissions and
 limitations under the License.
"""

import networkx as nx

from mo.graph.graph import Graph
from mo.middle.replacement import MiddleReplacementPattern


class AddIsCyclicAttribute(MiddleReplacementPattern):
    enabled = True

    def run_after(self):
        from extensions.middle.DeleteControlFlowEdges import DeleteControlFlowEdges
        return [DeleteControlFlowEdges]

    def run_before(self):
        return []

    @staticmethod
    def find_and_replace_pattern(graph: Graph):
        is_acyclic = nx.is_directed_acyclic_graph(graph)
        graph.graph['is_cyclic'] = not is_acyclic
