/* 
 * Mirai. Copyright (C) 2024 Vyn
 * This file is licensed under version 3 of the GNU General Public License (GPL-3.0-only)
 * The license can be found in the LICENSE file or at https://www.gnu.org/licenses/gpl-3.0.txt
 */

#ifndef MIRAI_TODOTXT_H
#define MIRAI_TODOTXT_H

#include "TaskItem.h"
#include "utils.h"
#include <fstream>
#include <iostream>
#include <iterator>
#include <memory>
#include <regex>
#include <stdexcept>
#include <string>
#include <vector>

namespace mirai {

	class TodoTxtFormat {
	public:

		static TaskList readFile() {
			std::ifstream file("../newqml/todo.txt");
			if (!file.is_open()) {
				throw std::runtime_error("todo.txt file not found");
			}
			std::vector<TaskItem> taskItems;
			std::string line;
			while (std::getline(file, line)) {
				auto taskItem = parseLine(line);
				taskItems.push_back(taskItem);
			}
			file.close();
			TaskList tasks({
				.tasks = taskItems
			});
			return tasks;
		}

		static void writeFile(TaskList& tasks) {
			std::ofstream file("../newqml/todo.txt");
			if (!file.is_open()) {
				throw std::runtime_error("can't create todo.txt");
			}
			for (const auto& task : tasks.getTasks()) {
				file << fieldWithSpace(task->state == DONE ? "x" : task->priority);
				file << fieldWithSpace(task->state == DONE ? task->getDate() : "");
				file << fieldWithSpace(task->getCreationDate());
				file << task->getText() << '\n';
			}
			file.close();
		}

	private:

		static std::string fieldWithSpace(const std::string& field) {
			if (field.length() == 0)
				return "";
			return (field + " ");
		}

		static TaskItem parseLine(const std::string& line) {
			std::smatch matches;
			std::regex regex("(^x )?(\\([A-Z]\\) )?([0-9]{4}-[0-9]{2}-[0-9]{2} )?([0-9]{4}-[0-9]{2}-[0-9]{2} )?(.*)");
			std::regex_match(line, matches, regex);
		 
			for (size_t i = 0; i < matches.size(); ++i) {
                std::ssub_match sub_match = matches[i];
                std::string piece = sub_match.str();
            }

			const TaskItemState taskState = trim_copy(matches[1].str()) == "x" ? DONE : TODO;
			const std::string priority = trim_copy(matches[2].str());
			const std::string firstDate = trim_copy(matches[3].str());
			const std::string secondDate = trim_copy(matches[4].str());
			const std::string text = trim_copy(matches[5].str());

			const std::string date = taskState == DONE ? firstDate : "";

			
			
			return {
				.text = text,
				.state = taskState,
				.date = date,
			};
		}
	};
}

#endif