package jalview.jbgui;

import java.io.File;
import java.util.Date;

import javax.swing.JFrame;
import javax.swing.JOptionPane;

import com.formdev.flatlaf.extras.FlatDesktop;

import jalview.bin.Console;
import jalview.io.BackupFiles;
import jalview.util.MessageManager;
import jalview.util.Platform;

public class QuitHandler
{
  public static enum QResponse
  {
    QUIT, CANCEL_QUIT, FORCE_QUIT
  };

  public static void setQuitHandler()
  {
    FlatDesktop.setQuitHandler(response -> {
      QResponse qresponse = getQuitResponse();
      switch (qresponse)
      {
      case QUIT:
        response.performQuit();
        break;
      case CANCEL_QUIT:
        response.cancelQuit();
        break;
      case FORCE_QUIT:
        response.performQuit();
        break;
      default:
        response.cancelQuit();
      }
    });
  }

  private static QResponse gotQuitResponse = QResponse.CANCEL_QUIT;

  private static QResponse returnResponse(QResponse qresponse)
  {
    gotQuitResponse = qresponse;
    return qresponse;
  }

  public static QResponse gotQuitResponse()
  {
    return gotQuitResponse;
  }

  public static QResponse getQuitResponse()
  {
    return getQuitResponse(true);
  }

  public static QResponse getQuitResponse(boolean ui)
  {
    if (gotQuitResponse() != QResponse.CANCEL_QUIT)
    {
      return returnResponse(getQuitResponse());
    }

    boolean interactive = ui && !Platform.isHeadless();
    // confirm quit if needed and wanted
    boolean confirmQuit = true;

    if (!interactive)
    {
      Console.debug("Non interactive quit -- not confirming");
      confirmQuit = false;
    }
    /* 
    else if (undostack is empty) {
      Console.debug("Nothing changed -- not confirming quit");
      confirmQuit = false
    }
    */
    else
    {
      confirmQuit = jalview.bin.Cache
              .getDefault(jalview.gui.Desktop.CONFIRM_KEYBOARD_QUIT, true);
      Console.debug("Jalview property '"
              + jalview.gui.Desktop.CONFIRM_KEYBOARD_QUIT
              + "' is/defaults to " + confirmQuit + " -- "
              + (confirmQuit ? "" : "not ") + "confirming quit");
    }

    int answer = JOptionPane.OK_OPTION;

    // if going to confirm, do it before the save in progress check to give
    // the save time to finish!
    if (confirmQuit)
    {
      answer = frameOnTop(MessageManager.getString("label.quit_jalview"),
              MessageManager.getString("action.quit"),
              JOptionPane.OK_CANCEL_OPTION, JOptionPane.PLAIN_MESSAGE);
    }

    if (answer == JOptionPane.CANCEL_OPTION)
    {
      Console.debug("QuitHandler: Quit action cancelled by user");
      return returnResponse(QResponse.CANCEL_QUIT);
    }

    // check for saves in progress
    int waitForSave = 5000; // MAKE THIS BETTER
    int waitIncrement = 2000;
    long startTime = new Date().getTime();
    boolean saving = BackupFiles.hasSavesInProgress();
    if (saving)
    {
      boolean waiting = (new Date().getTime() - startTime) < waitForSave;
      while (saving && waiting)
      {
        saving = !waitForSave(waitIncrement);
        waiting = (new Date().getTime() - startTime) < waitForSave;
      }

      if (saving) // still saving after a wait
      {
        StringBuilder messageSB = new StringBuilder(
                MessageManager.getString("label.save_in_progress"));
        for (File file : BackupFiles.savesInProgressFiles())
        {
          messageSB.append("\n");
          messageSB.append(file.getName());
        }
        int waitLonger = interactive ? JOptionPane.YES_OPTION
                : JOptionPane.NO_OPTION;
        while (saving && waitLonger == JOptionPane.YES_OPTION)
        {
          waitLonger = waitForceQuitCancelQuitOptionDialog(
                  messageSB.toString(),
                  MessageManager.getString("action.wait"));
          if (waitLonger == JOptionPane.YES_OPTION) // wait
          {
            Console.debug("*** YES answer=" + waitLonger);
            // do wait stuff
            saving = !waitForSave(waitIncrement);
          }
          else if (waitLonger == JOptionPane.NO_OPTION) // force quit
          {
            Console.debug("*** NO answer=" + waitLonger);
            // do a force quit
            return returnResponse(QResponse.FORCE_QUIT); // shouldn't reach this
          }
          else if (waitLonger == JOptionPane.CANCEL_OPTION) // cancel quit
          {
            Console.debug("*** CANCEL answer=" + waitLonger);
            return returnResponse(QResponse.CANCEL_QUIT);
          }
          else
          {
            Console.debug("**** Shouldn't have got here!");
          }
        }
      }
    }

    // not cancelled and not saving
    return returnResponse(QResponse.QUIT);
  }

  public static int frameOnTop(String label, String actionString,
          int JOPTIONPANE_OPTION, int JOPTIONPANE_MESSAGETYPE)
  {
    return frameOnTop(new JFrame(), label, actionString, JOPTIONPANE_OPTION,
            JOPTIONPANE_MESSAGETYPE);
  }

  public static int frameOnTop(JFrame dialogParent, String label,
          String actionString, int JOPTIONPANE_OPTION,
          int JOPTIONPANE_MESSAGETYPE)
  {
    // ensure Jalview window is brought to front for Quit confirmation
    // window to be visible

    // this method of raising the Jalview window is broken in java
    // jalviewDesktop.setVisible(true);
    // jalviewDesktop.toFront();

    // a better hack which works instead

    dialogParent.setAlwaysOnTop(true);

    int answer = JOptionPane.showConfirmDialog(dialogParent, label,
            actionString, JOPTIONPANE_OPTION, JOPTIONPANE_MESSAGETYPE);

    dialogParent.setAlwaysOnTop(false);
    dialogParent.dispose();

    return answer;
  }

  private static int waitForceQuitCancelQuitOptionDialog(Object message,
          String title)
  {
    JFrame dialogParent = new JFrame();
    dialogParent.setAlwaysOnTop(true);
    String wait = MessageManager.getString("action.wait");
    Object[] options = { wait,
        MessageManager.getString("action.force_quit"),
        MessageManager.getString("action.cancel_quit") };

    int answer = JOptionPane.showOptionDialog(dialogParent, message, title,
            JOptionPane.YES_NO_CANCEL_OPTION, JOptionPane.WARNING_MESSAGE,
            null, options, wait);

    return answer;
  }

  private static boolean waitForSave(long t)
  {
    boolean ret = false;
    try
    {
      Console.debug("Wait for save to complete: " + t + "ms");
      long c = 0;
      int i = 100;
      while (c < t)
      {
        Thread.sleep(i);
        c += i;
        ret = !BackupFiles.hasSavesInProgress();
        if (ret)
        {
          Console.debug(
                  "Save completed whilst waiting (" + c + "/" + t + "ms)");
          return ret;
        }
        if (c % 1000 < i) // just gone over another second
        {
          Console.debug("...waiting (" + c + "/" + t + "ms]");
        }
      }
    } catch (InterruptedException e)
    {
      Console.debug("Wait for save interrupted");
    }
    Console.debug("Save has " + (ret ? "" : "not ") + "completed");
    return ret;
  }

}