#ifndef MLPP_UTILITIES_H
#define MLPP_UTILITIES_H

//
//  Utilities.hpp
//
//  Created by Marc Melikyan on 1/16/21.
//

#include <string>
#include <tuple>
#include <vector>


class Utilities {
public:
	// Weight Init
	static std::vector<double> weightInitialization(int n, std::string type = "Default");
	static double biasInitialization();

	static std::vector<std::vector<double>> weightInitialization(int n, int m, std::string type = "Default");
	static std::vector<double> biasInitialization(int n);

	// Cost/Performance related Functions
	double performance(std::vector<double> y_hat, std::vector<double> y);
	double performance(std::vector<std::vector<double>> y_hat, std::vector<std::vector<double>> y);

	// Parameter Saving Functions
	void saveParameters(std::string fileName, std::vector<double> weights, double bias, bool app = 0, int layer = -1);
	void saveParameters(std::string fileName, std::vector<double> weights, std::vector<double> initial, double bias, bool app = 0, int layer = -1);
	void saveParameters(std::string fileName, std::vector<std::vector<double>> weights, std::vector<double> bias, bool app = 0, int layer = -1);

	// Gradient Descent related
	static void UI(std::vector<double> weights, double bias);
	static void UI(std::vector<double> weights, std::vector<double> initial, double bias);
	static void UI(std::vector<std::vector<double>>, std::vector<double> bias);
	static void CostInfo(int epoch, double cost_prev, double Cost);

	static std::vector<std::vector<std::vector<double>>> createMiniBatches(std::vector<std::vector<double>> inputSet, int n_mini_batch);
	static std::tuple<std::vector<std::vector<std::vector<double>>>, std::vector<std::vector<double>>> createMiniBatches(std::vector<std::vector<double>> inputSet, std::vector<double> outputSet, int n_mini_batch);
	static std::tuple<std::vector<std::vector<std::vector<double>>>, std::vector<std::vector<std::vector<double>>>> createMiniBatches(std::vector<std::vector<double>> inputSet, std::vector<std::vector<double>> outputSet, int n_mini_batch);

	// F1 score, Precision/Recall, TP, FP, TN, FN, etc.
	std::tuple<double, double, double, double> TF_PN(std::vector<double> y_hat, std::vector<double> y); //TF_PN = "True", "False", "Positive", "Negative"
	double recall(std::vector<double> y_hat, std::vector<double> y);
	double precision(std::vector<double> y_hat, std::vector<double> y);
	double accuracy(std::vector<double> y_hat, std::vector<double> y);
	double f1_score(std::vector<double> y_hat, std::vector<double> y);

private:
};


#endif /* Utilities_hpp */