#include "leaderboard.hpp"
#include <glibmm/fileutils.h>
#include <glibmm/keyfile.h>
#include <glibmm/miscutils.h>
#include <glib.h>
#include <glib/gstdio.h>

namespace {
std::string file_path() {
    return Glib::build_filename(
        Glib::get_user_config_dir(), "nomines", "leaderboard.ini");
}
} // namespace

void Leaderboard::load() {
    if (loaded_) return;
    loaded_ = true;

    // Migrate scores from pre-1.0 builds that stored them under minesweeper/
    auto path = file_path();
    auto legacy = Glib::build_filename(
        Glib::get_user_config_dir(), "minesweeper", "leaderboard.ini");
    bool migrated = false;
    if (!Glib::file_test(path, Glib::FileTest::EXISTS) &&
        Glib::file_test(legacy, Glib::FileTest::EXISTS)) {
        path = legacy;
        migrated = true;
    }

    try {
        auto kf = Glib::KeyFile::create();
        kf->load_from_file(path);
        for (const auto& group : kf->get_groups()) {
            if (kf->has_key(group, "best")) {
                times_[group.raw()] = kf->get_integer(group, "best");
            }
        }
        if (migrated) {
            // Stale legacy files can hold outdated/experimental data; drop it
            // so it can never be re-imported after the current file is gone.
            g_remove(legacy.c_str());
        }
    } catch (const Glib::Error&) {
        // No file yet or unreadable — start with an empty leaderboard
    }
}

bool Leaderboard::record(const std::string& difficulty, int seconds) {
    load();
    auto it = times_.find(difficulty);
    if (it != times_.end() && it->second <= seconds) return false;
    times_[difficulty] = seconds;
    save();
    return true;
}

std::optional<int> Leaderboard::best_time(const std::string& difficulty) const {
    auto it = times_.find(difficulty);
    if (it == times_.end()) return std::nullopt;
    return it->second;
}

void Leaderboard::clear() {
    load();
    times_.clear();
    save();
}

void Leaderboard::save() {
    auto kf = Glib::KeyFile::create();
    for (const auto& [difficulty, seconds] : times_) {
        kf->set_integer(difficulty, "best", seconds);
    }
    try {
        auto dir = Glib::path_get_dirname(file_path());
        g_mkdir_with_parents(dir.c_str(), 0700);
        kf->save_to_file(file_path());
    } catch (const Glib::Error&) {
        // Best-effort persistence; a failed save is not fatal
    }
}