#include <filesystem>
#include <format>
#include <fstream>
#include <iostream>
#include <vector>

// g++ -std=c++20 rename.cpp -o rename


// title 字段需要,可以先随便填
constexpr auto Template = R"(
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<episodedetails>
  <title>黑色五叶草</title>
  <showtitle>黑色五叶草</showtitle>
  <season>{}</season>
  <episode>{}</episode>
  <original_filename>{}</original_filename>
</episodedetails>
)";

struct SeasonRange {
    int start;
    int end;
    int season;
};
const std::vector<SeasonRange> ranges = {
    {1, 170, 1},    // 001-048  season 1 48集
};

// 文件夹内有 001.mkv-328.mkv 文件，使用C++ STL filesystem 根据上面的对应关系生成 001.nfo-328.nfo, 使用 std::format 传入字符串
// Template 输出最终内容写入对应的nfo文件

int main(int argc, char const *argv[]) {
    std::cout << "this is a simple rename app." << std::endl;
    for (const auto &entry : std::filesystem::directory_iterator(".")) {
        if (!entry.is_regular_file()) continue;

        const auto &path = entry.path();
        if (path.extension() != ".mkv") continue;

        const std::string filename = path.filename().string();
        const std::string stem = path.stem().string();
        std::cout <<"stem: "<<stem<<std::endl;

        // 提取前导数字部分
        size_t num_length = 0;
        while (num_length < stem.length() && std::isdigit(stem[num_length])) {
            num_length++;
        }

        if (num_length == 0) {
            std::cerr << "跳过无数字前缀的文件: " << filename << std::endl;
            continue;
        }

        try {
            const int episode_number = std::stoi(stem.substr(0, num_length));

            // 确定季度和集数
            int season = -1;
            int episode_in_season = -1;
            for (const auto &range : ranges) {
                if (episode_number >= range.start && episode_number <= range.end) {
                    season = range.season;
                    episode_in_season = episode_number - range.start + 1;
                    break;
                }
            }

            if (season == -1) {
                std::cerr << "未找到对应的季度: " << episode_number << std::endl;
                continue;
            }

            // 生成XML内容
            std::string xml_content = std::format(Template, season, episode_in_season, filename);

            // 写入.nfo文件
            std::filesystem::path nfo_path = path;
            nfo_path.replace_extension(".nfo");
            std::ofstream out_file(nfo_path);
            out_file << xml_content;
            std::cout <<"filename: "<<filename<< ", episode_number: "<<episode_number<<", episode_in_season: "<<episode_in_season<< std::endl;
            std::cout << "已生成: " << nfo_path.filename() << std::endl;
        } catch (const std::exception &e) {
            std::cerr << "处理文件 " << filename << " 时出错: " << e.what() << std::endl;
        }
    }
    return 0;
}