#include <QApplication>
#include <QPalette>
#include <QStyleFactory>
#include <QDir>
#include <QFile>
#include <QLockFile>
#include <QMessageBox>
#include <cstdio>
#ifdef _WIN32
#include <windows.h>
#include <tlhelp32.h>
#endif
#include "mainwindow.h"
#include "../db/db_manager.h"
#include "../transport/node_config.h"
#include "../transport/utun_node.h"
#include "../../lib/debug_config.h"

#ifdef _WIN32
static UtunNode* g_ctrl_node = nullptr;
static MainWindow* g_mainWindow = nullptr;

static DWORD count_threads(void) {
    DWORD pid = GetCurrentProcessId(), count = 0;
    HANDLE snap = CreateToolhelp32Snapshot(TH32CS_SNAPTHREAD, 0);
    if (snap == INVALID_HANDLE_VALUE) return 0;
    THREADENTRY32 te = { sizeof(te) };
    if (Thread32First(snap, &te)) {
        do { if (te.th32OwnerProcessID == pid) count++; }
        while (Thread32Next(snap, &te));
    }
    CloseHandle(snap);
    return count;
}

static BOOL WINAPI console_ctrl_handler(DWORD dwCtrlType) {
    if (dwCtrlType == CTRL_C_EVENT || dwCtrlType == CTRL_BREAK_EVENT) {
        if (g_mainWindow)
            QMetaObject::invokeMethod(g_mainWindow, [g_mainWindow] {
                g_mainWindow->requestShutdown();
            }, Qt::QueuedConnection);
        else if (g_ctrl_node)
            g_ctrl_node->requestStop();
        return TRUE;
    }
    return FALSE;
}
#endif

static struct ShutdownSentinel {
    ~ShutdownSentinel() {
        DEBUG_DEBUG(DEBUG_CATEGORY_GENERAL, "main: static destructors done");
#ifdef _WIN32
        DWORD threads = count_threads();
        DEBUG_DEBUG(DEBUG_CATEGORY_GENERAL, "main: threads at exit=%lu", (unsigned long)threads);
        if (threads > 4) {
            DEBUG_WARN(DEBUG_CATEGORY_GENERAL, "main: %lu hanging threads, TerminateProcess", (unsigned long)threads);
            fflush(nullptr);
            TerminateProcess(GetCurrentProcess(), 0);
        }
#endif
    }
} g_shutdown_sentinel;

int main(int argc, char *argv[]) {
#ifdef Q_OS_LINUX
    /* На Wayland композитор владеет позицией окна (move() игнорируется) —
     * для полноценного ручного move/resize с пропорцией запускаемся через XWayland. */
    if (!qEnvironmentVariableIsSet("QT_QPA_PLATFORM"))
        qputenv("QT_QPA_PLATFORM", "xcb");
#endif
    QApplication app(argc, argv);
    app.setApplicationName("vibechat");
    app.setQuitOnLastWindowClosed(false);

    /* single-instance: лог/БД/сокеты конфликтуют при втором запуске */
    QLockFile lock(QCoreApplication::applicationDirPath() + "/vibechat.lock");
    if (!lock.tryLock()) {
        QMessageBox::warning(nullptr, "vibechat", "vibechat is already running.");
        return 1;
    }

    app.setStyle(QStyleFactory::create("Fusion"));
    QPalette p;
    p.setColor(QPalette::Window,          QColor(53, 53, 53));
    p.setColor(QPalette::WindowText,      QColor(220, 220, 220));
    p.setColor(QPalette::Base,            QColor(42, 42, 42));
    p.setColor(QPalette::AlternateBase,   QColor(66, 66, 66));
    p.setColor(QPalette::ToolTipBase,     QColor(25, 25, 25));
    p.setColor(QPalette::ToolTipText,     QColor(220, 220, 220));
    p.setColor(QPalette::Text,            QColor(220, 220, 220));
    p.setColor(QPalette::Button,          QColor(53, 53, 53));
    p.setColor(QPalette::ButtonText,      QColor(220, 220, 220));
    p.setColor(QPalette::BrightText,      Qt::red);
    p.setColor(QPalette::Link,            QColor(42, 130, 218));
    p.setColor(QPalette::Highlight,       QColor(42, 130, 218));
    p.setColor(QPalette::HighlightedText, Qt::white);
    p.setColor(QPalette::Disabled, QPalette::Text, QColor(127, 127, 127));
    p.setColor(QPalette::Disabled, QPalette::ButtonText, QColor(127, 127, 127));
    app.setPalette(p);

    QString cfgDir = QCoreApplication::applicationDirPath();
    QString cfgPath = cfgDir + "/vibechat.cfg";
    /* миграция: старый конфиг chatgui.cfg → vibechat.cfg */
    if (!QFile::exists(cfgPath) && QFile::exists(cfgDir + "/chatgui.cfg"))
        QFile::rename(cfgDir + "/chatgui.cfg", cfgPath);

    NodeConfig cfg(cfgPath);
    bool needSave = false;

    if (!cfg.exists()) {
        if (!cfg.create("", 1333)) {
            qCritical("Failed to create config: %s", qPrintable(cfgPath));
            return 1;
        }
    } else {
        if (!cfg.load()) {
            qCritical("Cannot open/read config file: %s", qPrintable(cfgPath));
            return 1;
        }
        if (cfg.hasErrors()) {
            for (const auto& err : cfg.errors())
                fprintf(stderr, "CONFIG ERROR: %s\n", qPrintable(err));
            return 1;
        }
        if (cfg.privKey().length() != 64 || cfg.pubKey().length() != 64) {
            qWarning("Config: keys missing/invalid, regenerating identity");
            cfg.generateIdentity();
            needSave = true;
        }
        if (cfg.nodeId().length() != 16) {
            qWarning("Config: my_node_id missing/invalid, regenerating identity");
            cfg.generateIdentity();
            needSave = true;
        }
        if (needSave)
            cfg.save();
    }

    QString dbPath = cfg.dbPath();
    if (dbPath.isEmpty()) dbPath = "chat_data";
    if (!QDir::isAbsolutePath(dbPath))
        dbPath = QCoreApplication::applicationDirPath() + "/" + dbPath;
    QDir(dbPath).mkpath(".");

    QString debugFile = cfg.debugFile();
    if (debugFile.isEmpty()) debugFile = "chatgui.log";
    if (!QDir::isAbsolutePath(debugFile))
        debugFile = QCoreApplication::applicationDirPath() + "/" + debugFile;

    DbManager db;
    MainWindow w(nullptr, &db, cfgPath, dbPath, debugFile,
                 cfg.debugLevel(), cfg.debugCategories());
    w.show();

#ifdef _WIN32
    g_ctrl_node = w.utunNode();
    g_mainWindow = &w;
    SetConsoleCtrlHandler(console_ctrl_handler, TRUE);
#endif

    int ret = app.exec();
    DEBUG_DEBUG(DEBUG_CATEGORY_GENERAL, "main: app.exec() returned %d", ret);
    return ret;
}