namespace Netron.Diagramming.Core.Analysis {
  /// <summary>
  /// This interface describes the <see cref="Model"/> from the point of view of graph analysis.
  /// </summary>
  public interface IGraph {
    /// <summary>
    /// Get the in-degree of a node, the number of edges for which the node
    /// is the target.
    /// </summary>
    /// <param name="node"></param>
    /// <returns></returns>
    int InDegree(INode node);
    /// <summary>
    /// Get the out-degree of a node, the number of edges for which the node
    /// is the source.
    /// </summary>
    /// <param name="node"></param>
    /// <returns></returns>
    int OutDegree(INode node);
    /// <summary>
    /// Get the degree of a node, the number of edges for which a node
    /// is either the source or the target.
    /// </summary>
    /// <param name="node"></param>
    /// <returns></returns>
    int Degree(INode node);
    /// <summary>
    /// Indicates if the edges of this graph are directed or undirected.
    /// </summary>
    bool IsDirected { get; }
    /// <summary>
    /// Returns the nodes for the current page. This is the same as the <see cref="Model.Shapes"/> property except that the return type is
    /// here <see cref="INode"/> rather than <see cref="IShape"/> type.
    /// </summary>
    CollectionBase<INode> Nodes { get; }
    /// <summary>
    /// Get the source Node for the given Edge instance.
    /// </summary>
    /// <param name="edge"></param>
    /// <returns></returns>
    INode FromNode(IEdge edge);
    /// <summary>
    /// Get the target Node for the given Edge instance.
    /// </summary>
    /// <param name="edge"></param>
    /// <returns></returns>
    INode ToNode(IEdge edge);
    /// <summary>
    ///  Given an Edge and an incident Node, return the other Node
    /// connected to the edge.
    /// </summary>
    /// <param name="edge"></param>
    /// <param name="node"></param>
    /// <returns></returns>
    INode AdjacentNode(IEdge edge, INode node);
    /// <summary>
    /// Gets the collection of all adjacent nodes connected to the given node by an
    /// incoming edge (i.e., all nodes that "point" at this one).
    /// </summary>
    CollectionBase<INode> InNeighbors(INode node);
    /// <summary>
    /// Gets the collection of adjacent nodes connected to the given node by an
    /// outgoing edge (i.e., all nodes "pointed" to by this one).
    /// </summary>
    CollectionBase<INode> OutNeighbors(INode node);

    /// <summary>
    /// Get an iterator over all nodes connected to the given node.
    /// </summary>
    CollectionBase<INode> Neighbors(INode node);
    /// <summary>
    /// Gets the edges.
    /// </summary>
    /// <value>The edges.</value>
    CollectionBase<IEdge> Edges { get; }
    /// <summary>
    /// Returns the edges connected to the given node.
    /// </summary>
    /// <param name="node">The node.</param>
    /// <returns></returns>
    CollectionBase<IEdge> EdgesOf(INode node);

    /// <summary>
    /// Returns the incoming edges of the given node.
    /// </summary>
    /// <param name="node">The node.</param>
    /// <returns></returns>
    CollectionBase<IEdge> InEdges(INode node);

    /// <summary>
    /// Returns the outgoing edges attached to the given node.
    /// </summary>
    /// <param name="node">The node.</param>
    /// <returns></returns>
    CollectionBase<IEdge> OutEdges(INode node);

    /// <summary>
    /// Gets a spanning tree of the model or graph.
    /// </summary>
    /// <value>The spanning tree.</value>
    ITree SpanningTree { get; }

    /// <summary>
    /// Makes the spanning tree.
    /// </summary>
    /// <param name="node">The node.</param>
    void MakeSpanningTree(INode node);

    /// <summary>
    /// Clears the spanning tree.
    /// </summary>
    void ClearSpanningTree();







  }
}