#include "skincache.hpp"

#include <fcntl.h>
#include <fstream>
#include <filesystem>

#include "../vcpkgs/arm64-v8a-android/include/spdlog/spdlog.h"

const std::string& get_cache_file_full_path() {
    static std::string cache_file = [] {
        char cmdline[512] = {0};
        int fd = open("/proc/self/cmdline", O_RDONLY);
        if (fd != -1) {
            read(fd, cmdline, sizeof(cmdline));
            close(fd);
            return "/storage/emulated/0/Android/data/" + std::string(cmdline) + "/blhxskin";
        }
        return std::string();
    }();
    return cache_file;
}

bool SkinCache::has_ship(ShipId ship_id) {
    return m_ships_skin.contains(ship_id);
}

SkinCache::SkinId SkinCache::get_skin(ShipId ship_id) {
    return m_ships_skin.at(ship_id);
}

void SkinCache::save(ShipId ship_id, SkinId skin_id) {
    m_ships_skin[ship_id] = skin_id;
    save_to_file();
}

void SkinCache::save_to_file() {
    auto item_count = m_ships_skin.size();
    auto cached_data = std::unique_ptr<ShipSkin[]>(new ShipSkin[item_count]);

    auto cached_data_raw = cached_data.get();
    auto it = m_ships_skin.begin();
    for(int i = 0; it != m_ships_skin.end(); ++it, ++i) {
        cached_data_raw[i].ship_id = it->first;
        cached_data_raw[i].skin_id = it->second;
    }

    auto cache_file = std::ofstream(get_cache_file_full_path(), std::ios::binary | std::ios::trunc);
    if (!cache_file.is_open()) {
        return;
    }
    cache_file.write(reinterpret_cast<char *>(cached_data_raw), sizeof(ShipSkin) * item_count);
}

void SkinCache::clear() {
    m_ships_skin.clear();
    std::filesystem::remove(get_cache_file_full_path());
}

SkinCache& SkinCache::get_instance() {
    static SkinCache instance = [] {
        SkinCache cache;
        cache.load();
        return cache;
    }();

    return instance;
}

void SkinCache::load() {
    SPDLOG_INFO("Ship skin cache file: {}", get_cache_file_full_path());
    if(!std::filesystem::exists(get_cache_file_full_path())) {
        return;
    }
    auto file_size = std::filesystem::file_size(get_cache_file_full_path());
    if (file_size == 0) {
        return;
    }

    auto cache_file = std::ifstream(get_cache_file_full_path(), std::ios::binary);
    if (!cache_file.is_open()) {
        return;
    }
    auto cached_data = std::unique_ptr<ShipSkin[]>(new ShipSkin[file_size / sizeof(ShipSkin)]);
    cache_file.read(reinterpret_cast<char *>(cached_data.get()), file_size);

    for (int i = 0; i < file_size / sizeof(ShipSkin); i++) {
        const auto& item = cached_data[i];
        m_ships_skin[item.ship_id] = item.skin_id;
    }

}