using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

namespace Tensorflow.Keras.Layers

{

/// <summary>

/// A `Node` describes the connectivity between two layers.

/// </summary>

public class Node

{

public InputLayer outbound_layer;

public Layer[] inbound_layers;

public int[] node_indices;

public int[] tensor_indices;

public Tensor[] input_tensors;

public Tensor[] output_tensors;

public int[][] input_shapes;

public int[][] output_shapes;

/// <summary>

///

/// </summary>

/// <param name="outbound_layer">

/// the layer that takes

/// `input_tensors` and turns them into `output_tensors`

/// (the node gets created when the `call`

/// method of the layer was called).

/// </param>

/// <param name="inbound_layers">

/// a list of layers, the same length as `input_tensors`,

/// the layers from where `input_tensors` originate.

/// </param>

/// <param name="node_indices">

/// a list of integers, the same length as `inbound_layers`.

/// `node_indices[i]` is the origin node of `input_tensors[i]`

/// (necessary since each inbound layer might have several nodes,

/// e.g. if the layer is being shared with a different data stream).

/// </param>

/// <param name="tensor_indices"></param>

/// <param name="input_tensors">list of input tensors.</param>

/// <param name="output_tensors">list of output tensors.</param>

public Node(InputLayer outbound_layer,

Layer[] inbound_layers,

int[] node_indices,

int[] tensor_indices,

Tensor[] input_tensors,

Tensor[] output_tensors)

{

this.outbound_layer = outbound_layer;

this.inbound_layers = inbound_layers;

this.node_indices = node_indices;

this.tensor_indices = tensor_indices;

this.input_tensors = input_tensors;

this.output_tensors = output_tensors;

input_shapes = input_tensors.Select(x => x._shape_tuple()).ToArray();

output_shapes = output_tensors.Select(x => x._shape_tuple()).ToArray();

// Add nodes to all layers involved.

foreach (var layer in inbound_layers)

{

if (layer != null)

layer.outbound_nodes.Add(this);

}

outbound_layer.inbound_nodes.Add(this);

}

}

}