/*
	This file is part of solidity.

	solidity is free software: you can redistribute it and/or modify
	it under the terms of the GNU General Public License as published by
	the Free Software Foundation, either version 3 of the License, or
	(at your option) any later version.

	solidity 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
	GNU General Public License for more details.

	You should have received a copy of the GNU General Public License
	along with solidity.  If not, see <http://www.gnu.org/licenses/>.
*/
/**
 * Contains the main class that controls yul-phaser based on command-line parameters and
 * associated factories for building instances of phaser's components.
 */

#pragma once

#include <tools/yulPhaser/AlgorithmRunner.h>
#include <tools/yulPhaser/GeneticAlgorithms.h>

#include <boost/program_options.hpp>

#include <istream>
#include <memory>
#include <optional>
#include <ostream>
#include <string>

namespace solidity::langutil
{

class CharStream;

}

namespace solidity::phaser
{

class FitnessMetric;
class GeneticAlgorithm;
class Population;
class Program;
class ProgramCache;

enum class PhaserMode
{
	RunAlgorithm,
	PrintOptimisedPrograms,
	PrintOptimisedASTs,
};

enum class Algorithm
{
	Random,
	GEWEP,
	Classic,
};

enum class MetricChoice
{
	CodeSize,
	RelativeCodeSize,
};

enum class MetricAggregatorChoice
{
	Average,
	Sum,
	Maximum,
	Minimum,
};

std::istream& operator>>(std::istream& _inputStream, solidity::phaser::PhaserMode& _phaserMode);
std::ostream& operator<<(std::ostream& _outputStream, solidity::phaser::PhaserMode _phaserMode);
std::istream& operator>>(std::istream& _inputStream, solidity::phaser::Algorithm& _algorithm);
std::ostream& operator<<(std::ostream& _outputStream, solidity::phaser::Algorithm _algorithm);
std::istream& operator>>(std::istream& _inputStream, solidity::phaser::MetricChoice& _metric);
std::ostream& operator<<(std::ostream& _outputStream, solidity::phaser::MetricChoice _metric);
std::istream& operator>>(std::istream& _inputStream, solidity::phaser::MetricAggregatorChoice& _aggregator);
std::ostream& operator<<(std::ostream& _outputStream, solidity::phaser::MetricAggregatorChoice _aggregator);
std::istream& operator>>(std::istream& _inputStream, solidity::phaser::CrossoverChoice& _crossover);
std::ostream& operator<<(std::ostream& _outputStream, solidity::phaser::CrossoverChoice _crossover);

/**
 * Builds and validates instances of @a GeneticAlgorithm and its derived classes.
 */
class GeneticAlgorithmFactory
{
public:
	struct Options
	{
		Algorithm algorithm;
		size_t minChromosomeLength;
		size_t maxChromosomeLength;
		CrossoverChoice crossover;
		double uniformCrossoverSwapChance;

		std::optional<double> randomElitePoolSize;

		double gewepMutationPoolSize;
		double gewepCrossoverPoolSize;
		double gewepRandomisationChance;
		double gewepDeletionVsAdditionChance;
		std::optional<double> gewepGenesToRandomise;
		std::optional<double> gewepGenesToAddOrDelete;

		double classicElitePoolSize;
		double classicCrossoverChance;
		double classicMutationChance;
		double classicDeletionChance;
		double classicAdditionChance;

		static Options fromCommandLine(boost::program_options::variables_map const& _arguments);
	};

	static std::unique_ptr<GeneticAlgorithm> build(
		Options const& _options,
		size_t _populationSize
	);
};

/**
 * Builds and validates instances of @a FitnessMetric and its derived classes.
 */
class FitnessMetricFactory
{
public:
	struct Options
	{
		MetricChoice metric;
		MetricAggregatorChoice metricAggregator;
		size_t relativeMetricScale;
		size_t chromosomeRepetitions;

		static Options fromCommandLine(boost::program_options::variables_map const& _arguments);
	};

	static std::unique_ptr<FitnessMetric> build(
		Options const& _options,
		std::vector<Program> _programs,
		std::vector<std::shared_ptr<ProgramCache>> _programCaches
	);
};

/**
 * Builds and validates instances of @a Population.
 */
class PopulationFactory
{
public:
	struct Options
	{
		size_t minChromosomeLength;
		size_t maxChromosomeLength;
		std::vector<std::string> population;
		std::vector<size_t> randomPopulation;
		std::vector<std::string> populationFromFile;

		static Options fromCommandLine(boost::program_options::variables_map const& _arguments);
	};

	static Population build(
		Options const& _options,
		std::shared_ptr<FitnessMetric> _fitnessMetric
	);
	static Population buildFromStrings(
		std::vector<std::string> const& _geneSequences,
		std::shared_ptr<FitnessMetric> _fitnessMetric
	);
	static Population buildRandom(
		size_t _populationSize,
		size_t _minChromosomeLength,
		size_t _maxChromosomeLength,
		std::shared_ptr<FitnessMetric> _fitnessMetric
	);
	static Population buildFromFile(
		std::string const& _filePath,
		std::shared_ptr<FitnessMetric> _fitnessMetric
	);
};

/**
 * Builds and validates instances of @a ProgramCache.
 */
class ProgramCacheFactory
{
public:
	struct Options
	{
		bool programCacheEnabled;

		static Options fromCommandLine(boost::program_options::variables_map const& _arguments);
	};

	static std::vector<std::shared_ptr<ProgramCache>> build(
		Options const& _options,
		std::vector<Program> _programs
	);
};

/**
 * Builds and validates instances of @a Program.
 */
class ProgramFactory
{
public:
	struct Options
	{
		std::vector<std::string> inputFiles;
		std::string prefix;

		static Options fromCommandLine(boost::program_options::variables_map const& _arguments);
	};

	static std::vector<Program> build(Options const& _options);

private:
	static langutil::CharStream loadSource(std::string const& _sourcePath);
};

/**
 * Main class that controls yul-phaser based on command-line parameters. The class is responsible
 * for command-line parsing, initialisation of global objects (like the random number generator),
 * creating instances of main components using factories and feeding them into @a AlgorithmRunner.
 */
class Phaser
{
public:
	static void main(int argc, char** argv);

private:
	struct CommandLineDescription
	{
		boost::program_options::options_description keywordDescription;
		boost::program_options::positional_options_description positionalDescription;
	};

	static CommandLineDescription buildCommandLineDescription();
	static std::optional<boost::program_options::variables_map> parseCommandLine(int _argc, char** _argv);
	static void initialiseRNG(boost::program_options::variables_map const& _arguments);
	static AlgorithmRunner::Options buildAlgorithmRunnerOptions(boost::program_options::variables_map const& _arguments);

	static void runPhaser(boost::program_options::variables_map const& _arguments);
	static void runAlgorithm(
		boost::program_options::variables_map const& _arguments,
		Population _population,
		std::vector<std::shared_ptr<ProgramCache>> _programCaches
	);
	static void printOptimisedProgramsOrASTs(
		boost::program_options::variables_map const& _arguments,
		Population const& _population,
		std::vector<Program> _programs,
		PhaserMode phaserMode
	);
};

}