#pragma once
#include <filesystem>
namespace fs = std::filesystem;
#include "data.hpp"
#include "toolbox.hpp"
//#include "config.hpp"

template <typename T>
bool unit_test_cpu_vs_gpu(const np::Array<T>& cpu, const np::Array<T>& gpu) noexcept {
	if (cpu.shape != gpu.shape) {
#if __DEBUG
		fprintf(stderr, "Inequal shape !\n");
#endif
		return false;
	}
	size_t eq = 0;
	const size_t length = np::prod(cpu.shape);
	for (size_t i = 0; i < length; ++i)
		if (cpu[i] == gpu[i])
			++eq;

#if __DEBUG
	if (eq != length)
		printf("Incorrect results, Number of equalities : %s/%s <=> %.2f%% !\n", thousand_sep(eq).c_str(), thousand_sep(length).c_str(),
				static_cast<float64_t>(eq) / static_cast<float64_t>(length) * 100.0);
#endif

	return eq == length;
}

template <typename T>
bool unit_test_argsort_2d(const np::Array<T>& a, const np::Array<uint16_t>& indices) noexcept {
	if (a.shape != indices.shape) {
#if __DEBUG
		fprintf(stderr, "Inequal shape !\n");
#endif
		return false;
	}
	size_t correct = a.shape[0]; // First elements are always correctly sorted
	const size_t total = np::prod(a.shape);
	for(size_t i = 0; i < total; i += a.shape[1])
		for(size_t j = 0; j < a.shape[1] - 1; ++j){
			const size_t k = i + j;
			if(a[i + indices[k]] <= a[i + indices[k + 1]])
				++correct;
		}
#if __DEBUG
	if (correct != total)
		printf("Incorrect results, Number of equalities : %s/%s <=> %.2f%% !\n", thousand_sep(correct).c_str(), thousand_sep(total).c_str(),
				static_cast<float64_t>(correct) / static_cast<float64_t>(total) * 100.0);
#endif
	return correct == total;
}

template <typename T, typename F, typename... Args>
T benchmark_function(const char* step_name, const F& fnc, Args &&...args) noexcept {
#if __DEBUG == false
	printf("%s...\r", step_name);
	fflush(stdout); // manual flush is mandatory, otherwise it will not be shown immediately because the output is buffered
#endif
	const std::chrono::system_clock::time_point start = perf_counter_ns();
	const T res = fnc(std::forward<Args>(args)...);
	const long long timespent = duration_ns(perf_counter_ns() - start);
	printf("| %-49s | %18s | %-29s |\n", step_name, thousand_sep(timespent).c_str(), format_time_ns(timespent).c_str());
	return res;
}

template <typename F, typename... Args>
void benchmark_function_void(const char* step_name, const F& fnc, Args &&...args) noexcept {
#if __DEBUG == false
	printf("%s...\r", step_name);
	fflush(stdout); // manual flush is mandatory, otherwise it will not be shown immediately because the output is buffered
#endif
	const std::chrono::system_clock::time_point start = perf_counter_ns();
	fnc(std::forward<Args>(args)...);
	const long long timespent = duration_ns(perf_counter_ns() - start);
	printf("| %-49s | %18s | %-29s |\n", step_name, thousand_sep(timespent).c_str(), format_time_ns(timespent).c_str());
}

template <typename T, typename F, typename... Args>
np::Array<T> state_saver(const char* step_name, const char* filename, const bool& force_redo, const bool& save_state, const char* out_dir, const F& fnc, Args &&...args) noexcept {
	char filepath[BUFFER_SIZE] = { 0 };
	sprintf(filepath, "%s/%s.bin", out_dir, filename);

	np::Array<T> bin;
	if (!fs::exists(filepath) || force_redo) {
		bin = std::move(benchmark_function<np::Array<T>>(step_name, fnc, std::forward<Args>(args)...));
		if(save_state){
#if __DEBUG == false
			printf("Saving results of %s\r", step_name);
			fflush(stdout);
#endif
			save<T>(bin, filepath);
#if __DEBUG == false
			printf("%*c\r", 100, ' ');
			fflush(stdout);
#endif
		}
	} else {
#if __DEBUG == false
		printf("Loading results of %s\r", step_name);
		fflush(stdout);
#endif
		bin = std::move(load<T>(filepath));
		printf("| %-49s | %18s | %-29s |\n", step_name, "None", "loaded saved state");
	}
	return bin;
}

template <typename T, size_t N, typename F, typename... Args>
std::array<np::Array<T>, N> state_saver(const char* step_name, const std::vector<const char*>& filenames, const bool& force_redo, const bool& save_state, const char* out_dir, const F& fnc, Args &&...args) noexcept {
	char filepath[BUFFER_SIZE] = { 0 };
	bool abs = false;
	for (const char* filename : filenames){
		sprintf(filepath, "%s/%s.bin", out_dir, filename);
		if (!fs::exists(filepath)) {
			abs = true;
			break;
		}
	}

	std::array<np::Array<T>, N> bin;
	if (abs || force_redo) {
		bin = std::move(benchmark_function<std::array<np::Array<T>, N>>(step_name, fnc, std::forward<Args>(args)...));
		if (save_state){
#if __DEBUG == false
			printf("Saving results of %s\r", step_name);
			fflush(stdout);
#endif
			size_t i = 0;
			for (const char* filename : filenames){
				sprintf(filepath, "%s/%s.bin", out_dir, filename);
				save<T>(bin[i++], filepath);
			}
#if __DEBUG == false
			printf("%*c\r", 100, ' ');
			fflush(stdout);
#endif
		}
	} else {
#if __DEBUG == false
		printf("Loading results of %s\r", step_name);
		fflush(stdout);
#endif
		size_t i = 0;
		for (const char* filename : filenames){
			sprintf(filepath, "%s/%s.bin", out_dir, filename);
			bin[i++] = std::move(load<T>(filepath));
		}
		printf("| %-49s | %18s | %-29s |\n", step_name, "None", "loaded saved state");
	}
	return bin;
}

np::Array<uint16_t> argsort_2d_cpu(const np::Array<int32_t>&) noexcept;
np::Array<uint8_t> build_features(const uint16_t&, const uint16_t&) noexcept;
np::Array<int> select_percentile(const np::Array<uint8_t>&, const np::Array<uint8_t>&) noexcept;
np::Array<uint8_t> classify_viola_jones(const np::Array<float64_t>&, const np::Array<float64_t>&, const np::Array<int32_t>&) noexcept;
np::Array<float64_t> init_weights(const np::Array<uint8_t>&) noexcept;
std::tuple<int32_t, float64_t, np::Array<float64_t>> select_best(const np::Array<float64_t>&, const np::Array<float64_t>&, const np::Array<int32_t>&,
								const np::Array<uint8_t>&) noexcept;
std::array<np::Array<float64_t>, 2> train_viola_jones(const size_t&, const np::Array<int32_t>&, const np::Array<uint16_t>&, const np::Array<uint8_t>&) noexcept;
float64_t accuracy_score(const np::Array<uint8_t>&, const np::Array<uint8_t>&) noexcept;
float64_t precision_score(const np::Array<uint8_t>&, const np::Array<uint8_t>&) noexcept;
float64_t recall_score(const np::Array<uint8_t>&, const np::Array<uint8_t>&) noexcept;
float64_t f1_score(const np::Array<uint8_t>&, const np::Array<uint8_t>&) noexcept;
std::tuple<uint16_t, uint16_t, uint16_t, uint16_t> confusion_matrix(const np::Array<uint8_t>&, const np::Array<uint8_t>&) noexcept;