/*
Copyright (C) 2012 Sebastian Herbord. All rights reserved.

This file is part of Mod Organizer.

Mod Organizer 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.

Mod Organizer 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 Mod Organizer.  If not, see <http://www.gnu.org/licenses/>.
*/


#ifdef LEAK_CHECK_WITH_VLD
#include <wchar.h>
#include <vld.h>
#endif // LEAK_CHECK_WITH_VLD

#define WIN32_LEAN_AND_MEAN
#include <windows.h>
#include <DbgHelp.h>

#include <appconfig.h>
#include <utility.h>
#include <scopeguard.h>
#include "mainwindow.h"
#include <report.h>
#include "modlist.h"
#include "profile.h"
#include "spawn.h"
#include "executableslist.h"
#include "singleinstance.h"
#include "utility.h"
#include "helper.h"
#include "logbuffer.h"
#include "selectiondialog.h"
#include "moapplication.h"
#include "tutorialmanager.h"
#include "nxmaccessmanager.h"
#include "instancemanager.h"

#include <eh.h>
#include <windows_error.h>

#include <QApplication>
#include <QPushButton>
#include <QListWidget>
#include <QComboBox>
#include <QCheckBox>
#include <QDir>
#include <QFileInfo>
#include <QSettings>
#include <QWhatsThis>
#include <QToolBar>
#include <QFileDialog>
#include <QDesktopServices>
#include <QMessageBox>
#include <QSharedMemory>
#include <QBuffer>
#include <QSplashScreen>
#include <QDirIterator>
#include <QDesktopServices>
#include <QLibraryInfo>
#include <QSslSocket>

#include <boost/scoped_array.hpp>

#include <ShellAPI.h>

#include <cstdarg>
#include <iostream>
#include <stdexcept>


#pragma comment(linker, "/manifestDependency:\"name='dlls' processorArchitecture='x86' version='1.0.0.0' type='win32' \"")


using namespace MOBase;
using namespace MOShared;


bool createAndMakeWritable(const std::wstring &subPath)
{
  QString const dataPath = qApp->property("dataPath").toString();
  QString fullPath = dataPath + "/" + QString::fromStdWString(subPath);

  if (!QDir(fullPath).exists()) {
    QDir().mkdir(fullPath);
  }

  QFileInfo fileInfo(fullPath);
  if (!fileInfo.exists() || !fileInfo.isWritable()) {
    if (QMessageBox::question(nullptr, QObject::tr("Permissions required"),
        QObject::tr("The current user account doesn't have the required access rights to run "
           "Mod Organizer. The neccessary changes can be made automatically (the MO directory "
           "will be made writable for the current user account). You will be asked to run "
           "\"helper.exe\" with administrative rights."),
           QMessageBox::Yes | QMessageBox::Cancel) == QMessageBox::Yes) {
      if (!Helper::init(qApp->applicationDirPath().toStdWString(),
                        dataPath.toStdWString())) {
        return false;
      }
    } else {
      return false;
    }
    // no matter which directory didn't exist/wasn't writable, the helper
    // should have created them all so we don't have to worry this message box would appear repeatedly
  }
  return true;
}


bool bootstrap()
{
  // remove the temporary backup directory in case we're restarting after an update
  QString backupDirectory = qApp->applicationDirPath() + "/update_backup";
  if (QDir(backupDirectory).exists()) {
    shellDelete(QStringList(backupDirectory));
  }

  // cycle logfile
  removeOldFiles(qApp->property("dataPath").toString() + "/" + QString::fromStdWString(AppConfig::logPath()),
                 "usvfs*.log", 5, QDir::Name);

  createAndMakeWritable(AppConfig::profilesPath());
  createAndMakeWritable(AppConfig::modsPath());
  createAndMakeWritable(AppConfig::downloadPath());
  createAndMakeWritable(AppConfig::overwritePath());
  createAndMakeWritable(AppConfig::logPath());

  return true;
}


bool isNxmLink(const QString &link)
{
  return link.startsWith("nxm://", Qt::CaseInsensitive);
}

static LONG WINAPI MyUnhandledExceptionFilter(struct _EXCEPTION_POINTERS *exceptionPtrs)
{
  typedef BOOL (WINAPI *FuncMiniDumpWriteDump)(HANDLE process, DWORD pid, HANDLE file, MINIDUMP_TYPE dumpType,
                                               const PMINIDUMP_EXCEPTION_INFORMATION exceptionParam,
                                               const PMINIDUMP_USER_STREAM_INFORMATION userStreamParam,
                                               const PMINIDUMP_CALLBACK_INFORMATION callbackParam);
  LONG result = EXCEPTION_CONTINUE_SEARCH;

  HMODULE dbgDLL = ::LoadLibrary(L"dbghelp.dll");

  static const int errorLen = 200;
  char errorBuffer[errorLen + 1];
  memset(errorBuffer, '\0', errorLen + 1);

  if (dbgDLL) {
    FuncMiniDumpWriteDump funcDump = (FuncMiniDumpWriteDump)::GetProcAddress(dbgDLL, "MiniDumpWriteDump");
    if (funcDump) {
      QString dataPath = qApp->property("dataPath").toString();
      QString exeName = QFileInfo(qApp->applicationFilePath()).fileName();
      QString dumpName = dataPath + "/" + exeName + ".dmp";

      if (QMessageBox::question(nullptr, QObject::tr("Woops"),
                                QObject::tr("ModOrganizer has crashed! "
                                            "Should a diagnostic file be created? "
                                            "If you send me this file (%1) to sherb@gmx.net, "
                                            "the bug is a lot more likely to be fixed. "
                                            "Please include a short description of what you were "
                                            "doing when the crash happened"
                                            ).arg(dumpName),
                                QMessageBox::Yes | QMessageBox::No) == QMessageBox::Yes) {

        HANDLE dumpFile = ::CreateFile(dumpName.toStdWString().c_str(),
                                       GENERIC_WRITE, FILE_SHARE_WRITE, nullptr,
                                       CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, nullptr);
        if (dumpFile != INVALID_HANDLE_VALUE) {
          _MINIDUMP_EXCEPTION_INFORMATION exceptionInfo;
          exceptionInfo.ThreadId = ::GetCurrentThreadId();
          exceptionInfo.ExceptionPointers = exceptionPtrs;
          exceptionInfo.ClientPointers = false;

          BOOL success = funcDump(::GetCurrentProcess(), ::GetCurrentProcessId(), dumpFile,
                                  MiniDumpNormal, &exceptionInfo, nullptr, nullptr);

          ::FlushFileBuffers(dumpFile);
          ::CloseHandle(dumpFile);
          if (success) {
            return EXCEPTION_EXECUTE_HANDLER;
          }
          _snprintf(errorBuffer, errorLen, "failed to save minidump to %ls (error %lu)",
                    dumpName.toStdWString().c_str(), ::GetLastError());
        } else {
          _snprintf(errorBuffer, errorLen, "failed to create %ls (error %lu)",
                    dumpName.toStdWString().c_str(), ::GetLastError());
        }
      } else {
        return result;
      }
    } else {
      _snprintf(errorBuffer, errorLen, "dbghelp.dll outdated");
    }
  } else {
    _snprintf(errorBuffer, errorLen, "dbghelp.dll not found");
  }

  QMessageBox::critical(nullptr, QObject::tr("Woops"),
                        QObject::tr("ModOrganizer has crashed! Unfortunately I was not able to write a diagnostic file: %1").arg(errorBuffer));
  return result;
}

static bool HaveWriteAccess(const std::wstring &path)
{
  bool writable = false;

  const static SECURITY_INFORMATION requestedFileInformation = OWNER_SECURITY_INFORMATION | GROUP_SECURITY_INFORMATION | DACL_SECURITY_INFORMATION;

  DWORD length = 0;
  if (!::GetFileSecurityW(path.c_str(), requestedFileInformation, nullptr, 0UL, &length)
      && (::GetLastError() == ERROR_INSUFFICIENT_BUFFER)) {
    std::string tempBuffer;
    tempBuffer.reserve(length);
    PSECURITY_DESCRIPTOR security = (PSECURITY_DESCRIPTOR)tempBuffer.data();
    if (security
        && ::GetFileSecurity(path.c_str(), requestedFileInformation, security, length, &length)) {
      HANDLE token = nullptr;
      const static DWORD tokenDesiredAccess = TOKEN_IMPERSONATE | TOKEN_QUERY | TOKEN_DUPLICATE | STANDARD_RIGHTS_READ;
      if (!::OpenThreadToken(::GetCurrentThread(), tokenDesiredAccess, TRUE, &token)) {
        if (!::OpenProcessToken(::GetCurrentProcess(), tokenDesiredAccess, &token)) {
          throw std::runtime_error("Unable to get any thread or process token");
        }
      }

      HANDLE impersonatedToken = nullptr;
      if (::DuplicateToken(token, SecurityImpersonation, &impersonatedToken)) {
        GENERIC_MAPPING mapping = { 0xFFFFFFFF };
        mapping.GenericRead = FILE_GENERIC_READ;
        mapping.GenericWrite = FILE_GENERIC_WRITE;
        mapping.GenericExecute = FILE_GENERIC_EXECUTE;
        mapping.GenericAll = FILE_ALL_ACCESS;

        DWORD genericAccessRights = FILE_GENERIC_WRITE;
        ::MapGenericMask(&genericAccessRights, &mapping);

        PRIVILEGE_SET privileges = { 0 };
        DWORD grantedAccess = 0;
        DWORD privilegesLength = sizeof(privileges);
        BOOL result = 0;
        if (::AccessCheck(security, impersonatedToken, genericAccessRights, &mapping, &privileges, &privilegesLength, &grantedAccess, &result)) {
          writable = result != 0;
        }
        ::CloseHandle(impersonatedToken);
      }

      ::CloseHandle(token);
    }
  }
  return writable;
}


QString determineProfile(QStringList &arguments, const QSettings &settings)
{
  QString selectedProfileName = QString::fromUtf8(settings.value("selected_profile", "").toByteArray());
  { // see if there is a profile on the command line
    int profileIndex = arguments.indexOf("-p", 1);
    if ((profileIndex != -1) && (profileIndex < arguments.size() - 1)) {
      qDebug("profile overwritten on command line");
      selectedProfileName = arguments.at(profileIndex + 1);
    }
    arguments.removeAt(profileIndex);
    arguments.removeAt(profileIndex);
  }
  if (selectedProfileName.isEmpty()) {
    qDebug("no configured profile");
    selectedProfileName = "Default";
  } else {
    qDebug("configured profile: %s", qPrintable(selectedProfileName));
  }

  return selectedProfileName;
}

MOBase::IPluginGame *selectGame(QSettings &settings, QDir const &gamePath, MOBase::IPluginGame *game)
{
  settings.setValue("gameName", game->gameName());
  //Sadly, hookdll needs gamePath in order to run. So following code block is
  //commented out
  /*if (gamePath == game->gameDirectory()) {
    settings.remove("gamePath");
  } else*/ {
    QString gameDir = gamePath.absolutePath();
    game->setGamePath(gameDir);
    settings.setValue("gamePath", QDir::toNativeSeparators(gameDir).toUtf8().constData());
  }
  return game; //Woot
}


MOBase::IPluginGame *determineCurrentGame(QString const &moPath, QSettings &settings, PluginContainer const &plugins)
{
  //Determine what game we are running where. Be very paranoid in case the
  //user has done something odd.
  //If the game name has been set up, use that.
  QString gameName = settings.value("gameName", "").toString();
  if (!gameName.isEmpty()) {
    MOBase::IPluginGame *game = plugins.managedGame(gameName);
    if (game == nullptr) {
      reportError(QObject::tr("Plugin to handle %1 no longer installed").arg(gameName));
      return nullptr;
    }
    QString gamePath = QString::fromUtf8(settings.value("gamePath", "").toByteArray());
    if (gamePath == "") {
      gamePath = game->gameDirectory().absolutePath();
    }
    QDir gameDir(gamePath);
    if (game->looksValid(gameDir)) {
      return selectGame(settings, gameDir, game);
    }
  }

  //gameName wasn't set, or otherwise can't be found. Try looking through all
  //the plugins using the gamePath
  QString gamePath = QString::fromUtf8(settings.value("gamePath", "").toByteArray());
  if (!gamePath.isEmpty()) {
    QDir gameDir(gamePath);
    //Look to see if one of the installed games binary file exists in the current
    //game directory.
    for (IPluginGame * const game : plugins.plugins<IPluginGame>()) {
      if (game->looksValid(gameDir)) {
        return selectGame(settings, gameDir, game);
      }
    }
  }

  //OK, we are in a new setup or existing info is useless.
  //See if MO has been installed inside a game directory
  for (IPluginGame * const game : plugins.plugins<IPluginGame>()) {
    if (game->isInstalled() && moPath.startsWith(game->gameDirectory().absolutePath())) {
      //Found it.
      return selectGame(settings, game->gameDirectory(), game);
    }
  }

  //Try walking up the directory tree to see if MO has been installed inside a game
  {
    QDir gameDir(moPath);
    do {
      //Look to see if one of the installed games binary file exists in the current
      //directory.
      for (IPluginGame * const game : plugins.plugins<IPluginGame>()) {
        if (game->looksValid(gameDir)) {
          return selectGame(settings, gameDir, game);
        }
      }
      //OK, chop off the last directory and try again
    } while (gameDir.cdUp());
  }

  //Then try a selection dialogue.
  if (!gamePath.isEmpty() || !gameName.isEmpty()) {
    reportError(QObject::tr("Could not use configuration settings for game \"%1\", path \"%2\".").
                                                   arg(gameName).arg(gamePath));
  }

  SelectionDialog selection(QObject::tr("Please select the game to manage"), nullptr, QSize(32, 32));

  for (IPluginGame *game : plugins.plugins<IPluginGame>()) {
    if (game->isInstalled()) {
      QString path = game->gameDirectory().absolutePath();
      selection.addChoice(game->gameIcon(), game->gameName(), path, QVariant::fromValue(game));
    }
  }

  selection.addChoice(QString("Browse..."), QString(), QVariant::fromValue(static_cast<IPluginGame *>(nullptr)));

  while (selection.exec() != QDialog::Rejected) {
    IPluginGame * game = selection.getChoiceData().value<IPluginGame *>();
    if (game != nullptr) {
      return selectGame(settings, game->gameDirectory(), game);
    }

    gamePath = QFileDialog::getExistingDirectory(
          nullptr, QObject::tr("Please select the game to manage"), QString(),
          QFileDialog::ShowDirsOnly);

    if (!gamePath.isEmpty()) {
      QDir gameDir(gamePath);
      for (IPluginGame * const game : plugins.plugins<IPluginGame>()) {
        if (game->looksValid(gameDir)) {
          return selectGame(settings, gameDir, game);
        }
      }
      reportError(QObject::tr("No game identified in \"%1\". The directory is required to contain "
                              "the game binary and its launcher.").arg(gamePath));
    }
  }

  return nullptr;
}


// extend path to include dll directory so plugins don't need a manifest
// (using AddDllDirectory would be an alternative to this but it seems fairly
// complicated esp.
//  since it isn't easily accessible on Windows < 8
//  SetDllDirectory replaces other search directories and this seems to
//  propagate to child processes)
void setupPath()
{
  static const int BUFSIZE = 4096;

  qDebug("MO at: %s", qPrintable(QDir::toNativeSeparators(
                          QCoreApplication::applicationDirPath())));

  boost::scoped_array<TCHAR> oldPath(new TCHAR[BUFSIZE]);
  DWORD offset = ::GetEnvironmentVariable(TEXT("PATH"), oldPath.get(), BUFSIZE);
  if (offset > BUFSIZE) {
    oldPath.reset(new TCHAR[offset]);
    ::GetEnvironmentVariable(TEXT("PATH"), oldPath.get(), offset);
  }

  std::wstring newPath(oldPath.get());
  newPath += L";";
  newPath += ToWString(QDir::toNativeSeparators(
                           QCoreApplication::applicationDirPath()))
                 .c_str();
  newPath += L"\\dlls";

  ::SetEnvironmentVariableW(L"PATH", newPath.c_str());
}

int runApplication(MOApplication &application, SingleInstance &instance,
                   const QString &splashPath)
{
  qDebug("start main application");
  QPixmap pixmap(splashPath);
  QSplashScreen splash(pixmap);

  QString dataPath = application.property("dataPath").toString();
  qDebug("data path: %s", qPrintable(dataPath));

  if (!bootstrap()) {
    reportError("failed to set up data path");
    return 1;
  }

  QStringList arguments = application.arguments();

  try {
    qDebug("Working directory: %s", qPrintable(QDir::toNativeSeparators(QDir::currentPath())));
    splash.show();
  } catch (const std::exception &e) {
    reportError(e.what());
    return 1;
  }

  try {
    QSettings settings(dataPath + "/"
                           + QString::fromStdWString(AppConfig::iniFileName()),
                       QSettings::IniFormat);
    qDebug("initializing core");
    OrganizerCore organizer(settings);
    qDebug("initialize plugins");
    PluginContainer pluginContainer(&organizer);
    pluginContainer.loadPlugins();

    MOBase::IPluginGame *game = determineCurrentGame(
        application.applicationDirPath(), settings, pluginContainer);
    if (game == nullptr) {
      return 1;
    }
    if (splashPath.startsWith(':')) {
      // currently using MO splash, see if the plugin contains one
      QString pluginSplash
          = QString(":/%1/splash").arg(game->gameShortName());
      QImage image(pluginSplash);
      if (!image.isNull()) {
        image.save(dataPath + "/splash.png");
      } else {
        qDebug("no plugin splash");
      }
    }

    organizer.setManagedGame(game);
    organizer.createDefaultProfile();

    if (!settings.contains("game_edition")) {
      QStringList editions = game->gameVariants();
      if (editions.size() > 1) {
        SelectionDialog selection(
            QObject::tr("Please select the game edition you have (MO can't "
                        "start the game correctly if this is set "
                        "incorrectly!)"),
            nullptr);
        int index = 0;
        for (const QString &edition : editions) {
          selection.addChoice(edition, "", index++);
        }
        if (selection.exec() == QDialog::Rejected) {
          return 1;
        } else {
          settings.setValue("game_edition", selection.getChoiceString());
        }
      }
    }
    game->setGameVariant(settings.value("game_edition").toString());

    qDebug("managing game at %s", qPrintable(QDir::toNativeSeparators(
                                      game->gameDirectory().absolutePath())));

    organizer.updateExecutablesList(settings);

    QString selectedProfileName = determineProfile(arguments, settings);
    organizer.setCurrentProfile(selectedProfileName);

    // if we have a command line parameter, it is either a nxm link or
    // a binary to start
    if (arguments.size() > 1) {
      if (isNxmLink(arguments.at(1))) {
        qDebug("starting download from command line: %s",
               qPrintable(arguments.at(1)));
        organizer.externalMessage(arguments.at(1));
      } else {
        QString exeName = arguments.at(1);
        qDebug("starting %s from command line", qPrintable(exeName));
        arguments.removeFirst(); // remove application name (ModOrganizer.exe)
        arguments.removeFirst(); // remove binary name
        // pass the remaining parameters to the binary
        try {
          organizer.startApplication(exeName, arguments, QString(), QString());
          return 0;
        } catch (const std::exception &e) {
          reportError(
              QObject::tr("failed to start application: %1").arg(e.what()));
          return 1;
        }
      }
    }

    NexusInterface::instance()->getAccessManager()->startLoginCheck();

    qDebug("initializing tutorials");
    TutorialManager::init(
        qApp->applicationDirPath() + "/"
            + QString::fromStdWString(AppConfig::tutorialsPath()) + "/",
        &organizer);

    if (!application.setStyleFile(settings.value("Settings/style", "").toString())) {
      // disable invalid stylesheet
      settings.setValue("Settings/style", "");
    }

    int res = 1;
    { // scope to control lifetime of mainwindow
      // set up main window and its data structures
      MainWindow mainWindow(settings, organizer, pluginContainer);

      QObject::connect(&mainWindow, SIGNAL(styleChanged(QString)), &application,
                       SLOT(setStyleFile(QString)));
      QObject::connect(&instance, SIGNAL(messageSent(QString)), &organizer,
                       SLOT(externalMessage(QString)));

      mainWindow.readSettings();

      qDebug("displaying main window");
      mainWindow.show();

      splash.finish(&mainWindow);
      return application.exec();
    }
  } catch (const std::exception &e) {
    reportError(e.what());
    return 1;
  }
}


int main(int argc, char *argv[])
{
  SetUnhandledExceptionFilter(MyUnhandledExceptionFilter);

  MOApplication application(argc, argv);
  QStringList arguments = application.arguments();

  if ((arguments.length() >= 4) && (arguments.at(1) == "launch")) {
    // all we're supposed to do is launch another process
    QProcess process;
    process.setWorkingDirectory(QDir::fromNativeSeparators(arguments.at(2)));
    process.setProgram(QDir::fromNativeSeparators(arguments.at(3)));
    process.setArguments(arguments.mid(4));
    process.start();
    process.waitForFinished(-1);
    return process.exitCode();
  }

  setupPath();

  #if !defined(QT_NO_SSL)
      qDebug("ssl support: %d", QSslSocket::supportsSsl());
  #else
      qDebug("non-ssl build");
  #endif

  bool forcePrimary = false;
  if (arguments.contains("update")) {
    arguments.removeAll("update");
    forcePrimary = true;
  }

  SingleInstance instance(forcePrimary);
  if (!instance.primaryInstance()) {
    if ((arguments.size() == 2) && isNxmLink(arguments.at(1))) {
      qDebug("not primary instance, sending download message");
      instance.sendMessage(arguments.at(1));
      return 0;
    } else if (arguments.size() == 1) {
      QMessageBox::information(
          nullptr, QObject::tr("Mod Organizer"),
          QObject::tr("An instance of Mod Organizer is already running"));
      return 0;
    }
  } // we continue for the primary instance OR if MO was called with parameters

  do {
    QString dataPath;

    try {
      dataPath = InstanceManager::instance().determineDataPath();
    } catch (const std::exception &e) {
      QMessageBox::critical(nullptr, QObject::tr("Failed to set up instance"),
                            e.what());
      return 1;
    }
    application.setProperty("dataPath", dataPath);

    LogBuffer::init(100, QtDebugMsg, qApp->property("dataPath").toString() + "/logs/mo_interface.log");

    QString splash = dataPath + "/splash.png";
    if (!QFile::exists(dataPath + "/splash.png")) {
      splash = ":/MO/gui/splash";
    }

    int result = runApplication(application, instance, splash);
    if (result != INT_MAX) {
      return result;
    }
    argc = 1;
  } while (true);
}