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# Source code for networkx.drawing.nx_agraph

    """
    ***************
    Graphviz AGraph
    ***************

    Interface to pygraphviz AGraph class.

    Examples
    --------
    >>> G = nx.complete_graph(5)
    >>> A = nx.nx_agraph.to_agraph(G)
    >>> H = nx.nx_agraph.from_agraph(A)

    See Also
    --------
     - Pygraphviz: http://pygraphviz.github.io/
     - Graphviz:      https://www.graphviz.org
     - DOT Language:  http://www.graphviz.org/doc/info/lang.html
    """

    import os
    import tempfile

    import networkx as nx

    __all__ = [
        "from_agraph",
        "to_agraph",
        "write_dot",
        "read_dot",
        "graphviz_layout",
        "pygraphviz_layout",
        "view_pygraphviz",
    ]

    @nx._dispatchable(graphs=None, returns_graph=True)
    def from_agraph(A, create_using=None):
        """Returns a NetworkX Graph or DiGraph from a PyGraphviz graph.

        Parameters
        ----------
        A : PyGraphviz AGraph
          A graph created with PyGraphviz

        create_using : NetworkX graph constructor, optional (default=None)
           Graph type to create. If graph instance, then cleared before populated.
           If `None`, then the appropriate Graph type is inferred from `A`.

        Examples
        --------
        >>> K5 = nx.complete_graph(5)
        >>> A = nx.nx_agraph.to_agraph(K5)
        >>> G = nx.nx_agraph.from_agraph(A)

        Notes
        -----
        The Graph G will have a dictionary G.graph_attr containing
        the default graphviz attributes for graphs, nodes and edges.

        Default node attributes will be in the dictionary G.node_attr
        which is keyed by node.

        Edge attributes will be returned as edge data in G.  With
        edge_attr=False the edge data will be the Graphviz edge weight
        attribute or the value 1 if no edge weight attribute is found.

        """
        if create_using is None:
            if A.is_directed():
                if A.is_strict():
                    create_using = nx.DiGraph
                else:
                    create_using = nx.MultiDiGraph
            else:
                if A.is_strict():
                    create_using = nx.Graph
                else:
                    create_using = nx.MultiGraph

        # assign defaults
        N = nx.empty_graph(0, create_using)
        if A.name is not None:
            N.name = A.name

        # add graph attributes
        N.graph.update(A.graph_attr)

        # add nodes, attributes to N.node_attr
        for n in A.nodes():
            str_attr = {str(k): v for k, v in n.attr.items()}
            N.add_node(str(n), **str_attr)

        # add edges, assign edge data as dictionary of attributes
        for e in A.edges():
            u, v = str(e[0]), str(e[1])
            attr = dict(e.attr)
            str_attr = {str(k): v for k, v in attr.items()}
            if not N.is_multigraph():
                if e.name is not None:
                    str_attr["key"] = e.name
                N.add_edge(u, v, **str_attr)
            else:
                N.add_edge(u, v, key=e.name, **str_attr)

        # add default attributes for graph, nodes, and edges
        # hang them on N.graph_attr
        N.graph["graph"] = dict(A.graph_attr)
        N.graph["node"] = dict(A.node_attr)
        N.graph["edge"] = dict(A.edge_attr)
        return N

    def to_agraph(N):
        """Returns a pygraphviz graph from a NetworkX graph N.

        Parameters
        ----------
        N : NetworkX graph
          A graph created with NetworkX

        Examples
        --------
        >>> K5 = nx.complete_graph(5)
        >>> A = nx.nx_agraph.to_agraph(K5)

        Notes
        -----
        If N has an dict N.graph_attr an attempt will be made first
        to copy properties attached to the graph (see from_agraph)
        and then updated with the calling arguments if any.

        """
        try:
            import pygraphviz
        except ImportError as err:
            raise ImportError("requires pygraphviz http://pygraphviz.github.io/") from err
        directed = N.is_directed()
        strict = nx.number_of_selfloops(N) == 0 and not N.is_multigraph()

        A = pygraphviz.AGraph(name=N.name, strict=strict, directed=directed)

        # default graph attributes
        A.graph_attr.update(N.graph.get("graph", {}))
        A.node_attr.update(N.graph.get("node", {}))
        A.edge_attr.update(N.graph.get("edge", {}))

        A.graph_attr.update(
            (k, v) for k, v in N.graph.items() if k not in ("graph", "node", "edge")
        )

        # add nodes
        for n, nodedata in N.nodes(data=True):
            A.add_node(n)
            # Add node data
            a = A.get_node(n)
            for key, val in nodedata.items():
                if key == "pos":
                    a.attr["pos"] = f"{val[0]},{val[1]}!"
                else:
                    a.attr[key] = str(val)

        # loop over edges
        if N.is_multigraph():
            for u, v, key, edgedata in N.edges(data=True, keys=True):
                str_edgedata = {k: str(v) for k, v in edgedata.items() if k != "key"}
                A.add_edge(u, v, key=str(key))
                # Add edge data
                a = A.get_edge(u, v)
                a.attr.update(str_edgedata)

        else:
            for u, v, edgedata in N.edges(data=True):
                str_edgedata = {k: str(v) for k, v in edgedata.items()}
                A.add_edge(u, v)
                # Add edge data
                a = A.get_edge(u, v)
                a.attr.update(str_edgedata)

        return A

    def write_dot(G, path):
        """Write NetworkX graph G to Graphviz dot format on path.

        Parameters
        ----------
        G : graph
           A networkx graph
        path : filename
           Filename or file handle to write

        Notes
        -----
        To use a specific graph layout, call ``A.layout`` prior to `write_dot`.
        Note that some graphviz layouts are not guaranteed to be deterministic,
        see https://gitlab.com/graphviz/graphviz/-/issues/1767 for more info.
        """
        A = to_agraph(G)
        A.write(path)
        A.clear()
        return

    @nx._dispatchable(name="agraph_read_dot", graphs=None, returns_graph=True)
    def read_dot(path):
        """Returns a NetworkX graph from a dot file on path.

        Parameters
        ----------
        path : file or string
           File name or file handle to read.
        """
        try:
            import pygraphviz
        except ImportError as err:
            raise ImportError(
                "read_dot() requires pygraphviz http://pygraphviz.github.io/"
            ) from err
        A = pygraphviz.AGraph(file=path)
        gr = from_agraph(A)
        A.clear()
        return gr

    def graphviz_layout(G, prog="neato", root=None, args=""):
        """Create node positions for G using Graphviz.

        Parameters
        ----------
        G : NetworkX graph
          A graph created with NetworkX
        prog : string
          Name of Graphviz layout program
        root : string, optional
          Root node for twopi layout
        args : string, optional
          Extra arguments to Graphviz layout program

        Returns
        -------
        Dictionary of x, y, positions keyed by node.

        Examples
        --------
        >>> G = nx.petersen_graph()
        >>> pos = nx.nx_agraph.graphviz_layout(G)
        >>> pos = nx.nx_agraph.graphviz_layout(G, prog="dot")

        Notes
        -----
        This is a wrapper for pygraphviz_layout.

        Note that some graphviz layouts are not guaranteed to be deterministic,
        see https://gitlab.com/graphviz/graphviz/-/issues/1767 for more info.
        """
        return pygraphviz_layout(G, prog=prog, root=root, args=args)

    def pygraphviz_layout(G, prog="neato", root=None, args=""):
        """Create node positions for G using Graphviz.

        Parameters
        ----------
        G : NetworkX graph
          A graph created with NetworkX
        prog : string
          Name of Graphviz layout program
        root : string, optional
          Root node for twopi layout
        args : string, optional
          Extra arguments to Graphviz layout program

        Returns
        -------
        node_pos : dict
          Dictionary of x, y, positions keyed by node.

        Examples
        --------
        >>> G = nx.petersen_graph()
        >>> pos = nx.nx_agraph.graphviz_layout(G)
        >>> pos = nx.nx_agraph.graphviz_layout(G, prog="dot")

        Notes
        -----
        If you use complex node objects, they may have the same string
        representation and GraphViz could treat them as the same node.
        The layout may assign both nodes a single location. See Issue #1568
        If this occurs in your case, consider relabeling the nodes just
        for the layout computation using something similar to::

            >>> H = nx.convert_node_labels_to_integers(G, label_attribute="node_label")
            >>> H_layout = nx.nx_agraph.pygraphviz_layout(G, prog="dot")
            >>> G_layout = {H.nodes[n]["node_label"]: p for n, p in H_layout.items()}

        Note that some graphviz layouts are not guaranteed to be deterministic,
        see https://gitlab.com/graphviz/graphviz/-/issues/1767 for more info.
        """
        try:
            import pygraphviz
        except ImportError as err:
            raise ImportError("requires pygraphviz http://pygraphviz.github.io/") from err
        if root is not None:
            args += f"-Groot={root}"
        A = to_agraph(G)
        A.layout(prog=prog, args=args)
        node_pos = {}
        for n in G:
            node = pygraphviz.Node(A, n)
            try:
                xs = node.attr["pos"].split(",")
                node_pos[n] = tuple(float(x) for x in xs)
            except:
                print("no position for node", n)
                node_pos[n] = (0.0, 0.0)
        return node_pos

    @nx.utils.open_file(5, "w+b")
    def view_pygraphviz(
        G, edgelabel=None, prog="dot", args="", suffix="", path=None, show=True
    ):
        """Views the graph G using the specified layout algorithm.

        Parameters
        ----------
        G : NetworkX graph
            The machine to draw.
        edgelabel : str, callable, None
            If a string, then it specifies the edge attribute to be displayed
            on the edge labels. If a callable, then it is called for each
            edge and it should return the string to be displayed on the edges.
            The function signature of `edgelabel` should be edgelabel(data),
            where `data` is the edge attribute dictionary.
        prog : string
            Name of Graphviz layout program.
        args : str
            Additional arguments to pass to the Graphviz layout program.
        suffix : str
            If `filename` is None, we save to a temporary file.  The value of
            `suffix` will appear at the tail end of the temporary filename.
        path : str, None
            The filename used to save the image.  If None, save to a temporary
            file.  File formats are the same as those from pygraphviz.agraph.draw.
        show : bool, default = True
            Whether to display the graph with :mod:`PIL.Image.show`,
            default is `True`. If `False`, the rendered graph is still available
            at `path`.

        Returns
        -------
        path : str
            The filename of the generated image.
        A : PyGraphviz graph
            The PyGraphviz graph instance used to generate the image.

        Notes
        -----
        If this function is called in succession too quickly, sometimes the
        image is not displayed. So you might consider time.sleep(.5) between
        calls if you experience problems.

        Note that some graphviz layouts are not guaranteed to be deterministic,
        see https://gitlab.com/graphviz/graphviz/-/issues/1767 for more info.

        """
        if not len(G):
            raise nx.NetworkXException("An empty graph cannot be drawn.")

        # If we are providing default values for graphviz, these must be set
        # before any nodes or edges are added to the PyGraphviz graph object.
        # The reason for this is that default values only affect incoming objects.
        # If you change the default values after the objects have been added,
        # then they inherit no value and are set only if explicitly set.

        # to_agraph() uses these values.
        attrs = ["edge", "node", "graph"]
        for attr in attrs:
            if attr not in G.graph:
                G.graph[attr] = {}

        # These are the default values.
        edge_attrs = {"fontsize": "10"}
        node_attrs = {
            "style": "filled",
            "fillcolor": "#0000FF40",
            "height": "0.75",
            "width": "0.75",
            "shape": "circle",
        }
        graph_attrs = {}

        def update_attrs(which, attrs):
            # Update graph attributes. Return list of those which were added.
            added = []
            for k, v in attrs.items():
                if k not in G.graph[which]:
                    G.graph[which][k] = v
                    added.append(k)

        def clean_attrs(which, added):
            # Remove added attributes
            for attr in added:
                del G.graph[which][attr]
            if not G.graph[which]:
                del G.graph[which]

        # Update all default values
        update_attrs("edge", edge_attrs)
        update_attrs("node", node_attrs)
        update_attrs("graph", graph_attrs)

        # Convert to agraph, so we inherit default values
        A = to_agraph(G)

        # Remove the default values we added to the original graph.
        clean_attrs("edge", edge_attrs)
        clean_attrs("node", node_attrs)
        clean_attrs("graph", graph_attrs)

        # If the user passed in an edgelabel, we update the labels for all edges.
        if edgelabel is not None:
            if not callable(edgelabel):

                def func(data):
                    return "".join(["  ", str(data[edgelabel]), "  "])

            else:
                func = edgelabel

            # update all the edge labels
            if G.is_multigraph():
                for u, v, key, data in G.edges(keys=True, data=True):
                    # PyGraphviz doesn't convert the key to a string. See #339
                    edge = A.get_edge(u, v, str(key))
                    edge.attr["label"] = str(func(data))
            else:
                for u, v, data in G.edges(data=True):
                    edge = A.get_edge(u, v)
                    edge.attr["label"] = str(func(data))

        if path is None:
            ext = "png"
            if suffix:
                suffix = f"_{suffix}.{ext}"
            else:
                suffix = f".{ext}"
            path = tempfile.NamedTemporaryFile(suffix=suffix, delete=False)
        else:
            # Assume the decorator worked and it is a file-object.
            pass

        # Write graph to file
        A.draw(path=path, format=None, prog=prog, args=args)
        path.close()

        # Show graph in a new window (depends on platform configuration)
        if show:
            from PIL import Image

            Image.open(path.name).show()

        return path.name, A