/**++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 *
 *                                              PANIC
 *                              Portable Algorithms and Numerics In C++
 *
 *                       Scientific computing from scratch, with feeling.
 *
 * Copyright (c) 2026 Michelle Bausager
 *
 * This file is part of PANIC.
 *
 * PANIC is free software licensed under the GNU General Public License v3.0 or later.
 * You may redistribute and/or modify it under the terms of the GPL.
 *
 * PANIC is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
 * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 * See the LICENSE file for the full license text.
 *
 * SPDX-License-Identifier: GPL-3.0-or-later
 *
 *++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 *
 * Project Name:      PANIC
 * Module Name:       neural_network
 * File Name:         trainable_layer.hpp
 * Revision:          0.1.0
 * Date:              23-06-2026
 * Author:            Michelle Bausager
 *
 * Description:
 * Defines the base trainable_layer struct used in other layers in neural network
 *
 *++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*/
#pragma once
//---------------------------------------------------------------------------------------------------------------------------
// INCLUDE DESCRIPTION
//---------------------------------------------------------------------------------------------------------------------------
#include <config/types.hpp> // panic::uint_t, panic::int_t, and panic::real_t
#include <neural_network/layer/layer.hpp>
#include <tensor/matrix.hpp> // panic::tensor::real_matrix (uint_matrix, int_matrix)


namespace panic{
	namespace neural_network{



/**
 * @brief Base trainable_layer for the rest of the neural network library to use
 *
 *    	This base trainable_layer should be used in all layers/activations that have trainable variables
 * 		This is done so it's easy to make a list of layers in the model to loop over.
 * 		The virtual means it should use derived object's version when called with a pointer.
 * 		The =0 means the derivative object NEEDS to have these functions to work.
 * 
 * The struct is used for PANIC neural_network library.
 */
struct trainable_layer:layer{

    panic::tensor::real_matrix weights;
    panic::tensor::real_vector biases;

    panic::tensor::real_matrix dweights;
    panic::tensor::real_vector dbiases;

    /**
     * @brief Previous parameter updates used by momentum SGD.
     *
     * These remain empty unless an optimizer using momentum
     * initializes them.
     */
    panic::tensor::real_matrix weight_momentums;
    panic::tensor::real_vector bias_momentums;

    /**
     * @brief Previous parameter updates used by AdaGrad.
     *
     * These remain empty unless an optimizer using cache
     * initializes them.
     */
    panic::tensor::real_matrix weight_cache;
    panic::tensor::real_vector bias_cache;


	virtual ~trainable_layer() = default;


};



	} // namespace tensor
} // namespace panic