/*  This file is part of libravatarserv.
 *  Copyright © 2022 tastytea <tastytea@tastytea.de>
 *
 *  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, version 3.
 *
 *  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 <http://www.gnu.org/licenses/>.
 */

#include "config.hpp"
#include "fs-compat.hpp"
#include "hash.hpp"
#include "helpers.hpp"
#include "image.hpp"
#include "request.hpp"
#include "version.hpp"

#include <Magick++/Exception.h>
#include <Magick++/Image.h>

#include <cstring>
#include <iostream>
#include <stdexcept>
#include <string>

int main(int /*argc*/, char * /*argv*/[]) {
    using namespace libravatarserv;

    std::cout << "Server: libravatarserv/" << version << '\n';

    try {
        const std::string uri{read_env("REQUEST_URI")};
        if (uri.empty()) {
            std::cout << "Status: 400 Bad Request\n\n";
            throw std::runtime_error{"REQUEST_URI is empty"};
        }

        auto cfg{config::read()};

        auto req{request::parse(uri)};
        std::string email{hash::find_email(req, cfg.avatar_dir)};

        Magick::Image img;

        if (!email.empty()) {
            try {
                img = image::get(cfg.avatar_dir / email,
                                 static_cast<size_t>(req.size));
            } catch (const Magick::Exception &e) {
                std::cout << "Status: 500 Internal Server Error\n\n";
                std::cerr << "ERROR: " << e.what() << '\n';
                return 1;
            }
        } else {
            if (cfg.redirect) {
                std::cout << "Status: 307 Temporary Redirect\n";
                std::cout << "Location: https://seccdn.libravatar.org/avatar/"
                          << req.hash << "?s=" << req.size
                          << "&d=" << req.fallback << "\n\n";
                return 0;
            }
            if (req.fallback.empty()) {
                req.fallback = cfg.default_fallback;
            }
            if (req.fallback == "404") {
                std::cout << "Status: 404 Not Found\n\n";
                return 0;
            }

            if (req.fallback == "mp" || req.fallback == "mm") {
                if (!fs::exists(cfg.avatar_dir / "mp")) {
                    std::cout << "Status: 404 Not Found\n\n";
                    return 0;
                }
                email = "mp";
            } else if (req.fallback == "identicon" || req.fallback == "retro") {
                try {
                    img = image::generate_identicon(req);
                } catch (const std::exception &e) {
                    std::cout << "Status: 500 Internal Server Error\n\n";
                    std::cerr
                        << "ERROR: could not generate identicon: " << e.what()
                        << "\n";
                    return 1;
                }
            } else {
                std::cout << "Status: 501 Not Implemented\n\n";
            }
        }

        image::write(img);

    } catch (const std::runtime_error &e) {
        if (std::strlen(e.what()) != 0) {
            std::cerr << "ERROR: " << e.what() << '\n';
        }
        return 1;
    }

    return 0;
}