// yabridge: a Wine plugin bridge
// Copyright (C) 2020-2023 Robbert van der Helm
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <https://www.gnu.org/licenses/>.

#include "common.h"

#include <random>
#include <sstream>

#include "../utils.h"

namespace fs = ghc::filesystem;

/**
 * Used for generating random identifiers.
 */
constexpr char alphanumeric_characters[] =
    "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";

ghc::filesystem::path generate_endpoint_base(const std::string& plugin_name) {
    fs::path temp_directory = get_temporary_directory();

    std::random_device random_device;
    std::mt19937 rng(random_device());
    fs::path candidate_endpoint;
    do {
        std::string random_id;
        std::sample(
            alphanumeric_characters,
            alphanumeric_characters + strlen(alphanumeric_characters) - 1,
            std::back_inserter(random_id), 8, rng);

        // We'll get rid of the file descriptors immediately after accepting the
        // sockets, so putting them inside of a subdirectory would only leave
        // behind an empty directory
        std::ostringstream socket_name;
        socket_name << "yabridge-" << plugin_name << "-" << random_id;

        candidate_endpoint = temp_directory / socket_name.str();
    } while (fs::exists(candidate_endpoint));

    return candidate_endpoint;
}