/*

    Copyright (C) 2013 - 2014 Hong Jen Yee (PCMan) <pcman.tw@gmail.com>

    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 2 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, write to the Free Software Foundation, Inc.,
    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/


#include "mountoperation.h"
#include <glib/gi18n.h> // for _()
#include <QMessageBox>
#include <QPushButton>
#include <QEventLoop>
#include "mountoperationpassworddialog_p.h"
#include "mountoperationquestiondialog_p.h"
#include "ui_mount-operation-password.h"

namespace Fm {

MountOperation::MountOperation(bool interactive, QWidget* parent):
  QObject(parent),
  interactive_(interactive),
  running(false),
  op(g_mount_operation_new()),
  cancellable_(g_cancellable_new()),
  eventLoop(NULL),
  autoDestroy_(true) {
  
  g_signal_connect(op, "ask-password", G_CALLBACK(onAskPassword), this);
  g_signal_connect(op, "ask-question", G_CALLBACK(onAskQuestion), this);
  // g_signal_connect(op, "reply", G_CALLBACK(onReply), this);

#if GLIB_CHECK_VERSION(2, 20, 0)
  g_signal_connect(op, "aborted", G_CALLBACK(onAbort), this);
#endif
#if GLIB_CHECK_VERSION(2, 22, 0)
  g_signal_connect(op, "show-processes", G_CALLBACK(onShowProcesses), this);
#endif
#if GLIB_CHECK_VERSION(2, 34, 0)
  g_signal_connect(op, "show-unmount-progress", G_CALLBACK(onShowUnmountProgress), this);
#endif

}

MountOperation::~MountOperation() {
  qDebug("delete MountOperation");
  if(cancellable_) {
    cancel();
    g_object_unref(cancellable_);
  }

  if(eventLoop) { // if wait() is called to block the main loop, but the event loop is still running
    // NOTE: is this possible?
    eventLoop->exit(1);
  }

  if(op) {
    g_signal_handlers_disconnect_by_func(op, (gpointer)G_CALLBACK(onAskPassword), this);
    g_signal_handlers_disconnect_by_func(op, (gpointer)G_CALLBACK(onAskQuestion), this);
#if GLIB_CHECK_VERSION(2, 20, 0)
    g_signal_handlers_disconnect_by_func(op, (gpointer)G_CALLBACK(onAbort), this);
#endif
#if GLIB_CHECK_VERSION(2, 22, 0)
    g_signal_handlers_disconnect_by_func(op, (gpointer)G_CALLBACK(onShowProcesses), this);
#endif
#if GLIB_CHECK_VERSION(2, 34, 0)
    g_signal_handlers_disconnect_by_func(op, (gpointer)G_CALLBACK(onShowUnmountProgress), this);
#endif
    g_object_unref(op);
  }
  // qDebug("MountOperation deleted");
}

void MountOperation::onAbort(GMountOperation* _op, MountOperation* pThis) {

}

void MountOperation::onAskPassword(GMountOperation* _op, gchar* message, gchar* default_user, gchar* default_domain, GAskPasswordFlags flags, MountOperation* pThis) {
  qDebug("ask password");
  MountOperationPasswordDialog dlg(pThis, flags);
  dlg.setMessage(QString::fromUtf8(message));
  dlg.setDefaultUser(QString::fromUtf8(default_user));
  dlg.setDefaultDomain(QString::fromUtf8(default_domain));
  dlg.exec();
}

void MountOperation::onAskQuestion(GMountOperation* _op, gchar* message, GStrv choices, MountOperation* pThis) {
  qDebug("ask question");
  MountOperationQuestionDialog dialog(pThis, message, choices);
  dialog.exec();
}

/*
void MountOperation::onReply(GMountOperation* _op, GMountOperationResult result, MountOperation* pThis) {
  qDebug("reply");
}
*/

void MountOperation::onShowProcesses(GMountOperation* _op, gchar* message, GArray* processes, GStrv choices, MountOperation* pThis) {
  qDebug("show processes");
}

void MountOperation::onShowUnmountProgress(GMountOperation* _op, gchar* message, gint64 time_left, gint64 bytes_left, MountOperation* pThis) {
  qDebug("show unmount progress");
}

void MountOperation::onEjectMountFinished(GMount* mount, GAsyncResult* res, QPointer< MountOperation >* pThis) {
  if(*pThis) {
    GError* error = NULL;
    g_mount_eject_with_operation_finish(mount, res, &error);
    (*pThis)->handleFinish(error);
  }
  delete pThis;
}

void MountOperation::onEjectVolumeFinished(GVolume* volume, GAsyncResult* res, QPointer< MountOperation >* pThis) {
  if(*pThis) {
    GError* error = NULL;
    g_volume_eject_with_operation_finish(volume, res, &error);
    (*pThis)->handleFinish(error);
  }
  delete pThis;
}

void MountOperation::onMountFileFinished(GFile* file, GAsyncResult* res, QPointer< MountOperation >* pThis) {
  if(*pThis) {
    GError* error = NULL;
    g_file_mount_enclosing_volume_finish(file, res, &error);
    (*pThis)->handleFinish(error);
  }
  delete pThis;
}

void MountOperation::onMountVolumeFinished(GVolume* volume, GAsyncResult* res, QPointer< MountOperation >* pThis) {
  if(*pThis) {
    GError* error = NULL;
    g_volume_mount_finish(volume, res, &error);
    (*pThis)->handleFinish(error);
  }
  delete pThis;
}

void MountOperation::onUnmountMountFinished(GMount* mount, GAsyncResult* res, QPointer< MountOperation >* pThis) {
  if(*pThis) {
    GError* error = NULL;
    g_mount_unmount_with_operation_finish(mount, res, &error);
    (*pThis)->handleFinish(error);
  }
  delete pThis;
}

void MountOperation::handleFinish(GError* error) {
  qDebug("operation finished: %p", error);
  if(error) {
    bool showError = interactive_;
    if(error->domain == G_IO_ERROR) {
      if(error->code == G_IO_ERROR_FAILED) {
        // Generate a more human-readable error message instead of using a gvfs one.
        // The original error message is something like:
        // Error unmounting: umount exited with exit code 1:
        // helper failed with: umount: only root can unmount
        // UUID=18cbf00c-e65f-445a-bccc-11964bdea05d from /media/sda4 */
        // Why they pass this back to us? This is not human-readable for the users at all.
        if(strstr(error->message, "only root can ")) {
          g_free(error->message);
          error->message = g_strdup(_("Only system administrators have the permission to do this."));
        }
      }
      else if(error->code == G_IO_ERROR_FAILED_HANDLED)
        showError = false;
    }
    if(showError)
      QMessageBox::critical(NULL, QObject::tr("Error"), QString::fromUtf8(error->message));
  }

  Q_EMIT finished(error);

  if(eventLoop) { // if wait() is called to block the main loop
    eventLoop->exit(error != NULL ? 1 : 0);
    eventLoop = NULL;
  }

  if(error)
    g_error_free(error);

  // free ourself here!!
  if(autoDestroy_)
    deleteLater();
}

void MountOperation::prepareUnmount(GMount* mount) {
  /* ensure that CWD is not on the mounted filesystem. */
  char* cwd_str = g_get_current_dir();
  GFile* cwd = g_file_new_for_path(cwd_str);
  GFile* root = g_mount_get_root(mount);
  g_free(cwd_str);
  /* FIXME: This cannot cover 100% cases since symlinks are not checked.
    * There may be other cases that cwd is actually under mount root
    * but checking prefix is not enough. We already did our best, though. */
  if(g_file_has_prefix(cwd, root))
      g_chdir("/");
  g_object_unref(cwd);
  g_object_unref(root);
}

// block the operation used an internal QEventLoop and returns
// only after the whole operation is finished.
bool MountOperation::wait() {
  QEventLoop loop;
  eventLoop = &loop;
  int exitCode = loop.exec();
  return exitCode == 0 ? true : false;
}

} // namespace Fm