/*
 * This file is part of smolbote. It's copyrighted by the contributors recorded
 * in the version control history of the file, available from its original
 * location: https://neueland.iserlohn-fortress.net/gitea/aqua/smolbote
 *
 * SPDX-License-Identifier: GPL-3.0
 */

#include "browser.h"
#include "builtins.h"
#include "configuration.h"
#include "crashhandler.h"
#include "session/session.h"
#include "session/sessiondialog.h"
#include "util.h"
#include "version.h"
#include <QFile>
#include <QLibraryInfo>
#include <QPluginLoader>
#include <QTranslator>
#include <args.hxx>
#include <iostream>
#include <memory>
#include <plugininterface.h>
#include <pluginloader.h>
#include <spdlog/spdlog.h>

typedef std::function<void(const std::string &, std::vector<std::string>::const_iterator, std::vector<std::string>::const_iterator)> subcommand_func;
typedef std::unordered_map<std::string, subcommand_func> command_map;

// a helper function to join the keys of a command_map into a string
inline std::string join_keys(const command_map &map, const std::string sep = ", ")
{
    std::vector<std::string> keys(map.size());
    std::transform(map.begin(), map.end(), keys.begin(), [](auto pair) { return pair.first; });
    std::sort(keys.begin(), keys.end());

    std::string k;
    std::for_each(keys.begin(), keys.end() - 1, [&k, &sep](const std::string &piece) { k += piece + sep; });
    k += keys.back();

    return k;
}

#include <QStandardPaths>
inline std::string defaultUserConfigLocation()
{
#ifdef CONFIG_PATH_CONFIG
    return CONFIG_PATH_CONFIG;
#else
    // try to locate an existing config
    QString path = QStandardPaths::locate(QStandardPaths::ConfigLocation, "smolbote/smolbote.cfg");

    // it's possible there is no config, so set the path properly
    if(path.isEmpty())
        path = QStandardPaths::writableLocation(QStandardPaths::ConfigLocation) + "/smolbote/smolbote.cfg";

    return path.toStdString();
#endif
}

#include "config.h"
#if defined(CONFIG_USEPLASMA) && !defined(PLASMA)
#error "You have enabled Plasma integration, but Frameworks was not found."
#endif

#if defined(CONFIG_USEBREAKPAD) && !defined(BREAKPAD)
#error "You have enabled Breakpad integration, but Breakpad was not found."
#endif

int main(int argc, char **argv)
{
    // change log pattern
    spdlog::set_pattern("[%^%l%$] [%P:%t] %v");
#ifdef QT_DEBUG
    spdlog::set_level(spdlog::level::debug); // Set global log level to debug
#endif

    const std::vector<std::string> args(argv + 1, argv + argc);
    args::ArgumentParser parser("smolbote: yet another no-frills browser", "For more information on usage, refer to the manual page.");
    parser.Prog(argv[0]);

    args::HelpFlag cmd_help(parser, "help", "Display this help message.", { 'h', "help" });
    args::Flag cmd_version(parser, "version", "Display version information.", { 'v', "version" });
    args::Flag cmd_build(parser, "build", "Display build commit.", { 'b', "build" });

    args::ValueFlag<std::string> cmd_config(parser, "config", "Set the configuration file.", { 'c', "config" });

    args::Flag cmd_noRemote(parser, "no-remote", "Do not accept or send remote commands.", { "no-remote" });

    args::Flag cmd_pickSession(parser, "pick-session", "Show all available sessions and select which one to open", { "pick-session" });
    args::ValueFlag<std::string> cmd_session(parser, "session", "Open the specified session.", { 's', "session" });

    args::PositionalList<std::string> cmd_args(parser, "URL(s)", "List of URLs to open");

    try {
        auto next = parser.ParseArgs(args);

        if(cmd_version)
            return builtins::version();
        if(cmd_build)
            return builtins::build();

    } catch(args::Help) {
        std::cout << parser;
        //std::cout << "Available subcommands: " << command_keys << std::endl;
        return 0;

    } catch(args::Error e) {
        std::cerr << e.what() << std::endl;
        std::cerr << parser;
        return -1;
    }

    // Disable Chromium's crash handler so breakpad can capture crashes instead.
    // This has to be done before QtWebEngine gets initialized.
    const auto chromiumFlags = qgetenv("QTWEBENGINE_CHROMIUM_FLAGS");
    if(!chromiumFlags.contains("disable-in-process-stack-traces")) {
        qputenv("QTWEBENGINE_CHROMIUM_FLAGS", chromiumFlags + " --disable-in-process-stack-traces");
    }

    // create and load configuration
    const std::string config_path = [&]() {
        if(cmd_config)
            return args::get(cmd_config);
        else
            return defaultUserConfigLocation();
    }();
    std::unique_ptr<Configuration> config = std::make_unique<Configuration>(argc, argv, config_path);
    QTranslator translator;
    if(config->exists("browser.translation")) {
        translator.load(config->value<QString>("browser.translation").value());
    }

    QVector<QPluginLoader *> plugins;
    CommandHash_t pluginCommands;

    // Load plugins
    for(const QString &path : Util::files(config->value<QString>("plugins.path").value(), { "*.so", "*.dll" })) {
        auto *loader = new PluginLoader(path);
        const bool loaded = loader->load();
        spdlog::info("{} plugin {}", loaded ? "Loaded" : "Failed to load", qUtf8Printable(path));

        if(loaded) {
            plugins.append(loader);
            auto *plugin = qobject_cast<PluginInterface *>(loader->instance());
            pluginCommands.unite(plugin->commands());
        } else {
            spdlog::warn("{}", qUtf8Printable(loader->errorString()));
            delete loader;
        }
    }

    // argc, argv, allowSecondary
    Browser app(argc, argv);
    // set this, otherwise the webview becomes black when using a stylesheet
    app.setAttribute(Qt::AA_DontCreateNativeWidgetSiblings, true);
    app.installTranslator(&translator);
    if(config->exists("browser.locale")) {
        auto *locale = new QTranslator(&app);
        if(locale->load("qt_" + config->value<QString>("browser.locale").value(), QLibraryInfo::location(QLibraryInfo::TranslationsPath)))
            app.installTranslator(locale);
        else
            delete locale;
    }

    if(auto iconTheme = config->value<QString>("browser.iconTheme")) {
        QIcon::setThemeName(iconTheme.value());
    }

#ifdef CONFIG_USEBREAKPAD
    const std::string crashpath = config->value<std::string>("browser.crash.path").value_or("/tmp");
    assert(!crashpath.empty());

    CrashHandler::BreakpadContext ctx;
    google_breakpad::MinidumpDescriptor descriptor(crashpath.c_str());

    const auto crashHandler = config->value<std::string>("browser.crash.handler");
    if(crashHandler) {
        const int length = crashHandler.value().length() + 1;
        ctx.handler = new char[length];
        crashHandler.value().copy(ctx.handler, length - 1);
        ctx.handler[length - 1] = '\0';
    }

    // minidump descriptor, filter callback, minidump callback, callback_context, install handler, server_fd
    google_breakpad::ExceptionHandler eh(descriptor, nullptr, CrashHandler::dumpCallback, &ctx, true, -1);

#ifdef QT_DEBUG
    spdlog::info("Installed breakpad exception handler (path {})", crashpath);
#endif
#endif // CONFIG_USEBREAKPAD

    const auto profile = config->value<QString>("profile.default");

    app.setConfiguration(config); // app takes ownership of config
    app.setup(plugins);

    QStringList urls;

    for(const auto &u : args::get(cmd_args)) {
        if(pluginCommands.contains(QString::fromStdString(u))) {
            return pluginCommands.value(QString::fromStdString(u))();
        } else {
            urls.append(QString::fromStdString(u));
        }
    }
    if(urls.isEmpty())
        urls.append(QString());

    // if app is primary, create new sessions from received messages
    if(app.isPrimary() && !cmd_noRemote) {
        QObject::connect(&app, &Browser::receivedMessage, &app, [](quint32 instanceId, QByteArray message) {
            Q_UNUSED(instanceId);
            auto doc = QJsonDocument::fromJson(message);
            Session::restoreSession(doc.object());
        });
    }

    {
        QJsonObject sessionData;

        if(cmd_pickSession) {
            auto *dlg = new SessionDialog();
            if(const auto pick = dlg->pickSession())
                sessionData = pick.value();
            else
                sessionData = Session::fromCommandLine(profile.value(), urls);
        } else if(cmd_session) {
            QFile sessionJson(QString::fromStdString(args::get(cmd_session)));
            if(sessionJson.open(QIODevice::ReadOnly | QIODevice::Text)) {
                sessionData = QJsonDocument::fromJson(sessionJson.readAll()).object();
                sessionJson.close();
            }
        } else {
            sessionData = Session::fromCommandLine(profile.value(), urls);
        }

        if(app.isPrimary() || cmd_noRemote) {
            Session::restoreSession(sessionData);
        } else {
            // app is secondary and not standalone
            return app.sendMessage(QJsonDocument(sessionData).toJson());
        }
    }

    return app.exec();
}