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from collections import UserDict

import pytest

import networkx as nx
from networkx.utils import edges_equal

from .test_graph import BaseAttrGraphTester
from .test_graph import TestGraph as _TestGraph


class BaseMultiGraphTester(BaseAttrGraphTester):
    def test_has_edge(self):
        G = self.K3
        assert G.has_edge(0, 1)
        assert not G.has_edge(0, -1)
        assert G.has_edge(0, 1, 0)
        assert not G.has_edge(0, 1, 1)

    def test_get_edge_data(self):
        G = self.K3
        assert G.get_edge_data(0, 1) == {0: {}}
        assert G[0][1] == {0: {}}
        assert G[0][1][0] == {}
        assert G.get_edge_data(10, 20) is None
        assert G.get_edge_data(0, 1, 0) == {}

    def test_adjacency(self):
        G = self.K3
        assert dict(G.adjacency()) == {
            0: {1: {0: {}}, 2: {0: {}}},
            1: {0: {0: {}}, 2: {0: {}}},
            2: {0: {0: {}}, 1: {0: {}}},
        }

    def deepcopy_edge_attr(self, H, G):
        assert G[1][2][0]["foo"] == H[1][2][0]["foo"]
        G[1][2][0]["foo"].append(1)
        assert G[1][2][0]["foo"] != H[1][2][0]["foo"]

    def shallow_copy_edge_attr(self, H, G):
        assert G[1][2][0]["foo"] == H[1][2][0]["foo"]
        G[1][2][0]["foo"].append(1)
        assert G[1][2][0]["foo"] == H[1][2][0]["foo"]

    def graphs_equal(self, H, G):
        assert G._adj == H._adj
        assert G._node == H._node
        assert G.graph == H.graph
        assert G.name == H.name
        if not G.is_directed() and not H.is_directed():
            assert H._adj[1][2][0] is H._adj[2][1][0]
            assert G._adj[1][2][0] is G._adj[2][1][0]
        else:  # at least one is directed
            if not G.is_directed():
                G._pred = G._adj
                G._succ = G._adj
            if not H.is_directed():
                H._pred = H._adj
                H._succ = H._adj
            assert G._pred == H._pred
            assert G._succ == H._succ
            assert H._succ[1][2][0] is H._pred[2][1][0]
            assert G._succ[1][2][0] is G._pred[2][1][0]

    def same_attrdict(self, H, G):
        # same attrdict in the edgedata
        old_foo = H[1][2][0]["foo"]
        H.adj[1][2][0]["foo"] = "baz"
        assert G._adj == H._adj
        H.adj[1][2][0]["foo"] = old_foo
        assert G._adj == H._adj

        old_foo = H.nodes[0]["foo"]
        H.nodes[0]["foo"] = "baz"
        assert G._node == H._node
        H.nodes[0]["foo"] = old_foo
        assert G._node == H._node

    def different_attrdict(self, H, G):
        # used by graph_equal_but_different
        old_foo = H[1][2][0]["foo"]
        H.adj[1][2][0]["foo"] = "baz"
        assert G._adj != H._adj
        H.adj[1][2][0]["foo"] = old_foo
        assert G._adj == H._adj

        old_foo = H.nodes[0]["foo"]
        H.nodes[0]["foo"] = "baz"
        assert G._node != H._node
        H.nodes[0]["foo"] = old_foo
        assert G._node == H._node

    def test_to_undirected(self):
        G = self.K3
        self.add_attributes(G)
        H = nx.MultiGraph(G)
        self.is_shallow_copy(H, G)
        H = G.to_undirected()
        self.is_deepcopy(H, G)

    def test_to_directed(self):
        G = self.K3
        self.add_attributes(G)
        H = nx.MultiDiGraph(G)
        self.is_shallow_copy(H, G)
        H = G.to_directed()
        self.is_deepcopy(H, G)

    def test_number_of_edges_selfloops(self):
        G = self.K3
        G.add_edge(0, 0)
        G.add_edge(0, 0)
        G.add_edge(0, 0, key="parallel edge")
        G.remove_edge(0, 0, key="parallel edge")
        assert G.number_of_edges(0, 0) == 2
        G.remove_edge(0, 0)
        assert G.number_of_edges(0, 0) == 1

    def test_edge_lookup(self):
        G = self.Graph()
        G.add_edge(1, 2, foo="bar")
        G.add_edge(1, 2, "key", foo="biz")
        assert edges_equal(G.edges[1, 2, 0], {"foo": "bar"})
        assert edges_equal(G.edges[1, 2, "key"], {"foo": "biz"})

    def test_edge_attr(self):
        G = self.Graph()
        G.add_edge(1, 2, key="k1", foo="bar")
        G.add_edge(1, 2, key="k2", foo="baz")
        assert isinstance(G.get_edge_data(1, 2), G.edge_key_dict_factory)
        assert all(
            isinstance(d, G.edge_attr_dict_factory) for u, v, d in G.edges(data=True)
        )
        assert edges_equal(
            G.edges(keys=True, data=True),
            [(1, 2, "k1", {"foo": "bar"}), (1, 2, "k2", {"foo": "baz"})],
        )
        assert edges_equal(
            G.edges(keys=True, data="foo"), [(1, 2, "k1", "bar"), (1, 2, "k2", "baz")]
        )

    def test_edge_attr4(self):
        G = self.Graph()
        G.add_edge(1, 2, key=0, data=7, spam="bar", bar="foo")
        assert edges_equal(
            G.edges(data=True), [(1, 2, {"data": 7, "spam": "bar", "bar": "foo"})]
        )
        G[1][2][0]["data"] = 10  # OK to set data like this
        assert edges_equal(
            G.edges(data=True), [(1, 2, {"data": 10, "spam": "bar", "bar": "foo"})]
        )

        G.adj[1][2][0]["data"] = 20
        assert edges_equal(
            G.edges(data=True), [(1, 2, {"data": 20, "spam": "bar", "bar": "foo"})]
        )
        G.edges[1, 2, 0]["data"] = 21  # another spelling, "edge"
        assert edges_equal(
            G.edges(data=True), [(1, 2, {"data": 21, "spam": "bar", "bar": "foo"})]
        )
        G.adj[1][2][0]["listdata"] = [20, 200]
        G.adj[1][2][0]["weight"] = 20
        assert edges_equal(
            G.edges(data=True),
            [
                (
                    1,
                    2,
                    {
                        "data": 21,
                        "spam": "bar",
                        "bar": "foo",
                        "listdata": [20, 200],
                        "weight": 20,
                    },
                )
            ],
        )


class TestMultiGraph(BaseMultiGraphTester, _TestGraph):
    def setup_method(self):
        self.Graph = nx.MultiGraph
        # build K3
        ed1, ed2, ed3 = ({0: {}}, {0: {}}, {0: {}})
        self.k3adj = {0: {1: ed1, 2: ed2}, 1: {0: ed1, 2: ed3}, 2: {0: ed2, 1: ed3}}
        self.k3edges = [(0, 1), (0, 2), (1, 2)]
        self.k3nodes = [0, 1, 2]
        self.K3 = self.Graph()
        self.K3._adj = self.k3adj
        self.K3._node = {}
        self.K3._node[0] = {}
        self.K3._node[1] = {}
        self.K3._node[2] = {}

    def test_data_input(self):
        G = self.Graph({1: [2], 2: [1]}, name="test")
        assert G.name == "test"
        expected = [(1, {2: {0: {}}}), (2, {1: {0: {}}})]
        assert sorted(G.adj.items()) == expected

    def test_data_multigraph_input(self):
        # standard case with edge keys and edge data
        edata0 = {"w": 200, "s": "foo"}
        edata1 = {"w": 201, "s": "bar"}
        keydict = {0: edata0, 1: edata1}
        dododod = {"a": {"b": keydict}}

        multiple_edge = [("a", "b", 0, edata0), ("a", "b", 1, edata1)]
        single_edge = [("a", "b", 0, keydict)]

        G = self.Graph(dododod, multigraph_input=True)
        assert list(G.edges(keys=True, data=True)) == multiple_edge
        G = self.Graph(dododod, multigraph_input=None)
        assert list(G.edges(keys=True, data=True)) == multiple_edge
        G = self.Graph(dododod, multigraph_input=False)
        assert list(G.edges(keys=True, data=True)) == single_edge

        # test round-trip to_dict_of_dict and MultiGraph constructor
        G = self.Graph(dododod, multigraph_input=True)
        H = self.Graph(nx.to_dict_of_dicts(G))
        assert nx.is_isomorphic(G, H) is True  # test that default is True
        for mgi in [True, False]:
            H = self.Graph(nx.to_dict_of_dicts(G), multigraph_input=mgi)
            assert nx.is_isomorphic(G, H) == mgi

    # Set up cases for when incoming_graph_data is not multigraph_input
    etraits = {"w": 200, "s": "foo"}
    egraphics = {"color": "blue", "shape": "box"}
    edata = {"traits": etraits, "graphics": egraphics}
    dodod1 = {"a": {"b": edata}}
    dodod2 = {"a": {"b": etraits}}
    dodod3 = {"a": {"b": {"traits": etraits, "s": "foo"}}}
    dol = {"a": ["b"]}

    multiple_edge = [("a", "b", "traits", etraits), ("a", "b", "graphics", egraphics)]
    single_edge = [("a", "b", 0, {})]  # type: ignore[var-annotated]
    single_edge1 = [("a", "b", 0, edata)]
    single_edge2 = [("a", "b", 0, etraits)]
    single_edge3 = [("a", "b", 0, {"traits": etraits, "s": "foo"})]

    cases = [  # (dod, mgi, edges)
        (dodod1, True, multiple_edge),
        (dodod1, False, single_edge1),
        (dodod2, False, single_edge2),
        (dodod3, False, single_edge3),
        (dol, False, single_edge),
    ]

    @pytest.mark.parametrize("dod, mgi, edges", cases)
    def test_non_multigraph_input(self, dod, mgi, edges):
        G = self.Graph(dod, multigraph_input=mgi)
        assert list(G.edges(keys=True, data=True)) == edges
        G = nx.to_networkx_graph(dod, create_using=self.Graph, multigraph_input=mgi)
        assert list(G.edges(keys=True, data=True)) == edges

    mgi_none_cases = [
        (dodod1, multiple_edge),
        (dodod2, single_edge2),
        (dodod3, single_edge3),
    ]

    @pytest.mark.parametrize("dod, edges", mgi_none_cases)
    def test_non_multigraph_input_mgi_none(self, dod, edges):
        # test constructor without to_networkx_graph for mgi=None
        G = self.Graph(dod)
        assert list(G.edges(keys=True, data=True)) == edges

    raise_cases = [dodod2, dodod3, dol]

    @pytest.mark.parametrize("dod", raise_cases)
    def test_non_multigraph_input_raise(self, dod):
        # cases where NetworkXError is raised
        pytest.raises(nx.NetworkXError, self.Graph, dod, multigraph_input=True)
        pytest.raises(
            nx.NetworkXError,
            nx.to_networkx_graph,
            dod,
            create_using=self.Graph,
            multigraph_input=True,
        )

    def test_getitem(self):
        G = self.K3
        assert G[0] == {1: {0: {}}, 2: {0: {}}}
        with pytest.raises(KeyError):
            G.__getitem__("j")
        with pytest.raises(TypeError):
            G.__getitem__(["A"])

    def test_remove_node(self):
        G = self.K3
        G.remove_node(0)
        assert G.adj == {1: {2: {0: {}}}, 2: {1: {0: {}}}}
        with pytest.raises(nx.NetworkXError):
            G.remove_node(-1)

    def test_add_edge(self):
        G = self.Graph()
        G.add_edge(0, 1)
        assert G.adj == {0: {1: {0: {}}}, 1: {0: {0: {}}}}
        G = self.Graph()
        G.add_edge(*(0, 1))
        assert G.adj == {0: {1: {0: {}}}, 1: {0: {0: {}}}}
        G = self.Graph()
        with pytest.raises(ValueError):
            G.add_edge(None, "anything")

    def test_add_edge_conflicting_key(self):
        G = self.Graph()
        G.add_edge(0, 1, key=1)
        G.add_edge(0, 1)
        assert G.number_of_edges() == 2
        G = self.Graph()
        G.add_edges_from([(0, 1, 1, {})])
        G.add_edges_from([(0, 1)])
        assert G.number_of_edges() == 2

    def test_add_edges_from(self):
        G = self.Graph()
        G.add_edges_from([(0, 1), (0, 1, {"weight": 3})])
        assert G.adj == {
            0: {1: {0: {}, 1: {"weight": 3}}},
            1: {0: {0: {}, 1: {"weight": 3}}},
        }
        G.add_edges_from([(0, 1), (0, 1, {"weight": 3})], weight=2)
        assert G.adj == {
            0: {1: {0: {}, 1: {"weight": 3}, 2: {"weight": 2}, 3: {"weight": 3}}},
            1: {0: {0: {}, 1: {"weight": 3}, 2: {"weight": 2}, 3: {"weight": 3}}},
        }
        G = self.Graph()
        edges = [
            (0, 1, {"weight": 3}),
            (0, 1, (("weight", 2),)),
            (0, 1, 5),
            (0, 1, "s"),
        ]
        G.add_edges_from(edges)
        keydict = {0: {"weight": 3}, 1: {"weight": 2}, 5: {}, "s": {}}
        assert G._adj == {0: {1: keydict}, 1: {0: keydict}}

        # too few in tuple
        with pytest.raises(nx.NetworkXError):
            G.add_edges_from([(0,)])
        # too many in tuple
        with pytest.raises(nx.NetworkXError):
            G.add_edges_from([(0, 1, 2, 3, 4)])
        # not a tuple
        with pytest.raises(TypeError):
            G.add_edges_from([0])

    def test_multigraph_add_edges_from_four_tuple_misordered(self):
        """add_edges_from expects 4-tuples of the format (u, v, key, data_dict).

        Ensure 4-tuples of form (u, v, data_dict, key) raise exception.
        """
        G = nx.MultiGraph()
        with pytest.raises(TypeError):
            # key/data values flipped in 4-tuple
            G.add_edges_from([(0, 1, {"color": "red"}, 0)])

    def test_remove_edge(self):
        G = self.K3
        G.remove_edge(0, 1)
        assert G.adj == {0: {2: {0: {}}}, 1: {2: {0: {}}}, 2: {0: {0: {}}, 1: {0: {}}}}

        with pytest.raises(nx.NetworkXError):
            G.remove_edge(-1, 0)
        with pytest.raises(nx.NetworkXError):
            G.remove_edge(0, 2, key=1)

    def test_remove_edges_from(self):
        G = self.K3.copy()
        G.remove_edges_from([(0, 1)])
        kd = {0: {}}
        assert G.adj == {0: {2: kd}, 1: {2: kd}, 2: {0: kd, 1: kd}}
        G.remove_edges_from([(0, 0)])  # silent fail
        self.K3.add_edge(0, 1)
        G = self.K3.copy()
        G.remove_edges_from(list(G.edges(data=True, keys=True)))
        assert G.adj == {0: {}, 1: {}, 2: {}}
        G = self.K3.copy()
        G.remove_edges_from(list(G.edges(data=False, keys=True)))
        assert G.adj == {0: {}, 1: {}, 2: {}}
        G = self.K3.copy()
        G.remove_edges_from(list(G.edges(data=False, keys=False)))
        assert G.adj == {0: {}, 1: {}, 2: {}}
        G = self.K3.copy()
        G.remove_edges_from([(0, 1, 0), (0, 2, 0, {}), (1, 2)])
        assert G.adj == {0: {1: {1: {}}}, 1: {0: {1: {}}}, 2: {}}

    def test_remove_multiedge(self):
        G = self.K3
        G.add_edge(0, 1, key="parallel edge")
        G.remove_edge(0, 1, key="parallel edge")
        assert G.adj == {
            0: {1: {0: {}}, 2: {0: {}}},
            1: {0: {0: {}}, 2: {0: {}}},
            2: {0: {0: {}}, 1: {0: {}}},
        }
        G.remove_edge(0, 1)
        kd = {0: {}}
        assert G.adj == {0: {2: kd}, 1: {2: kd}, 2: {0: kd, 1: kd}}
        with pytest.raises(nx.NetworkXError):
            G.remove_edge(-1, 0)


class TestEdgeSubgraph:
    """Unit tests for the :meth:`MultiGraph.edge_subgraph` method."""

    def setup_method(self):
        # Create a doubly-linked path graph on five nodes.
        G = nx.MultiGraph()
        nx.add_path(G, range(5))
        nx.add_path(G, range(5))
        # Add some node, edge, and graph attributes.
        for i in range(5):
            G.nodes[i]["name"] = f"node{i}"
        G.adj[0][1][0]["name"] = "edge010"
        G.adj[0][1][1]["name"] = "edge011"
        G.adj[3][4][0]["name"] = "edge340"
        G.adj[3][4][1]["name"] = "edge341"
        G.graph["name"] = "graph"
        # Get the subgraph induced by one of the first edges and one of
        # the last edges.
        self.G = G
        self.H = G.edge_subgraph([(0, 1, 0), (3, 4, 1)])

    def test_correct_nodes(self):
        """Tests that the subgraph has the correct nodes."""
        assert [0, 1, 3, 4] == sorted(self.H.nodes())

    def test_correct_edges(self):
        """Tests that the subgraph has the correct edges."""
        assert [(0, 1, 0, "edge010"), (3, 4, 1, "edge341")] == sorted(
            self.H.edges(keys=True, data="name")
        )

    def test_add_node(self):
        """Tests that adding a node to the original graph does not
        affect the nodes of the subgraph.

        """
        self.G.add_node(5)
        assert [0, 1, 3, 4] == sorted(self.H.nodes())

    def test_remove_node(self):
        """Tests that removing a node in the original graph does
        affect the nodes of the subgraph.

        """
        self.G.remove_node(0)
        assert [1, 3, 4] == sorted(self.H.nodes())

    def test_node_attr_dict(self):
        """Tests that the node attribute dictionary of the two graphs is
        the same object.

        """
        for v in self.H:
            assert self.G.nodes[v] == self.H.nodes[v]
        # Making a change to G should make a change in H and vice versa.
        self.G.nodes[0]["name"] = "foo"
        assert self.G.nodes[0] == self.H.nodes[0]
        self.H.nodes[1]["name"] = "bar"
        assert self.G.nodes[1] == self.H.nodes[1]

    def test_edge_attr_dict(self):
        """Tests that the edge attribute dictionary of the two graphs is
        the same object.

        """
        for u, v, k in self.H.edges(keys=True):
            assert self.G._adj[u][v][k] == self.H._adj[u][v][k]
        # Making a change to G should make a change in H and vice versa.
        self.G._adj[0][1][0]["name"] = "foo"
        assert self.G._adj[0][1][0]["name"] == self.H._adj[0][1][0]["name"]
        self.H._adj[3][4][1]["name"] = "bar"
        assert self.G._adj[3][4][1]["name"] == self.H._adj[3][4][1]["name"]

    def test_graph_attr_dict(self):
        """Tests that the graph attribute dictionary of the two graphs
        is the same object.

        """
        assert self.G.graph is self.H.graph


class CustomDictClass(UserDict):
    pass


class MultiGraphSubClass(nx.MultiGraph):
    node_dict_factory = CustomDictClass  # type: ignore[assignment]
    node_attr_dict_factory = CustomDictClass  # type: ignore[assignment]
    adjlist_outer_dict_factory = CustomDictClass  # type: ignore[assignment]
    adjlist_inner_dict_factory = CustomDictClass  # type: ignore[assignment]
    edge_key_dict_factory = CustomDictClass  # type: ignore[assignment]
    edge_attr_dict_factory = CustomDictClass  # type: ignore[assignment]
    graph_attr_dict_factory = CustomDictClass  # type: ignore[assignment]


class TestMultiGraphSubclass(TestMultiGraph):
    def setup_method(self):
        self.Graph = MultiGraphSubClass
        # build K3
        self.k3edges = [(0, 1), (0, 2), (1, 2)]
        self.k3nodes = [0, 1, 2]
        self.K3 = self.Graph()
        self.K3._adj = self.K3.adjlist_outer_dict_factory(
            {
                0: self.K3.adjlist_inner_dict_factory(),
                1: self.K3.adjlist_inner_dict_factory(),
                2: self.K3.adjlist_inner_dict_factory(),
            }
        )
        self.K3._pred = {0: {}, 1: {}, 2: {}}
        for u in self.k3nodes:
            for v in self.k3nodes:
                if u != v:
                    d = {0: {}}
                    self.K3._adj[u][v] = d
                    self.K3._adj[v][u] = d
        self.K3._node = self.K3.node_dict_factory()
        self.K3._node[0] = self.K3.node_attr_dict_factory()
        self.K3._node[1] = self.K3.node_attr_dict_factory()
        self.K3._node[2] = self.K3.node_attr_dict_factory()