#!/usr/bin/env python
# -*- coding: utf-8 -*-
import argparse
import codecs
import distutils.spawn
import os.path
import platform
import re
import sys
import subprocess
import shutil
from time import time
import webbrowser as wb

from functools import partial
from collections import defaultdict

try:
    from PyQt5.QtGui import *
    from PyQt5.QtCore import *
    from PyQt5.QtWidgets import *
except ImportError:
    # needed for py3+qt4
    # Ref:
    # http://pyqt.sourceforge.net/Docs/PyQt4/incompatible_apis.html
    # http://stackoverflow.com/questions/21217399/pyqt4-qtcore-qvariant-object-instead-of-a-string
    if sys.version_info.major >= 3:
        import sip
        sip.setapi('QVariant', 2)
    from PyQt4.QtGui import *
    from PyQt4.QtCore import *
import matplotlib
matplotlib.use('Qt5Agg')
from matplotlib.backends.backend_qt5agg import FigureCanvasQTAgg as FigureCanvas
import matplotlib.pyplot as plt


from libs.combobox import ComboBox
from libs.resources import *
from libs.constants import *
from libs.utils import *
from libs.settings import Settings
from libs.shape import Shape, DEFAULT_LINE_COLOR, DEFAULT_FILL_COLOR
from libs.stringBundle import StringBundle
from libs.canvas import Canvas
from libs.zoomWidget import ZoomWidget
from libs.labelDialog import LabelDialog
from libs.colorDialog import ColorDialog
from libs.labelFile import LabelFile, LabelFileError, LabelFileFormat
from libs.toolBar import ToolBar
from libs.pascal_voc_io import PascalVocReader
from libs.pascal_voc_io import XML_EXT
from libs.yolo_io import YoloReader
from libs.yolo_io import TXT_EXT
from libs.create_ml_io import CreateMLReader
from libs.create_ml_io import JSON_EXT
from libs.ustr import ustr
from libs.hashableQListWidgetItem import HashableQListWidgetItem
from libs.label_handle import *

__appname__ = 'labelImg'


class WindowMixin(object):

    def menu(self, title, actions=None):
        menu = self.menuBar().addMenu(title)
        if actions:
            add_actions(menu, actions)
        return menu

    def toolbar(self, title, actions=None):
        toolbar = ToolBar(title)
        toolbar.setObjectName(u'%sToolBar' % title)
        # toolbar.setOrientation(Qt.Vertical)
        toolbar.setToolButtonStyle(Qt.ToolButtonTextUnderIcon)
        if actions:
            add_actions(toolbar, actions)
        self.addToolBar(Qt.LeftToolBarArea, toolbar)
        return toolbar


class MainWindow(QMainWindow, WindowMixin):
    FIT_WINDOW, FIT_WIDTH, MANUAL_ZOOM = list(range(3))

    def __init__(self, default_filename=None, default_prefdef_class_file=None, default_save_dir=None):
        super(MainWindow, self).__init__()

        QShortcut("e", self, self.edit_label)
        QShortcut("s", self, lambda:self.zoom_request(3000))

        self.setWindowTitle(__appname__)

        # Load setting in the main thread
        self.settings = Settings()
        self.settings.load()
        settings = self.settings

        self.os_name = platform.system()

        # Load string bundle for i18n
        self.string_bundle = StringBundle.get_bundle()
        get_str = lambda str_id: self.string_bundle.get_string(str_id)

        # Save as Pascal voc xml
        self.default_save_dir = default_save_dir
        self.label_file_format = settings.get(SETTING_LABEL_FILE_FORMAT, LabelFileFormat.PASCAL_VOC)

        # For loading all image under a directory
        self.m_img_list = []
        self.dir_name = None
        self.label_hist = []
        self.last_open_dir = None
        self.cur_img_idx = 0
        self.img_count = 1

        # For speed curve
        self.speed_data = []

        # Whether we need to save or not.
        self.dirty = False

        self._no_selection_slot = False
        self._beginner = True
        self.screencast = "https://youtu.be/p0nR2YsCY_U"

        # Load predefined classes to the list
        self.load_predefined_classes(default_prefdef_class_file)

        # Main widgets and related state.
        self.label_dialog = LabelDialog(parent=self, list_item=self.label_hist)

        self.items_to_shapes = {}
        self.shapes_to_items = {}
        self.prev_label_text = ''

        list_layout = QVBoxLayout()
        list_layout.setContentsMargins(0, 0, 0, 0)

        # Create a widget for using default label
        self.use_default_label_checkbox = QCheckBox(get_str('useDefaultLabel'))
        self.use_default_label_checkbox.setChecked(False)
        self.default_label_text_line = QLineEdit()
        use_default_label_qhbox_layout = QHBoxLayout()
        use_default_label_qhbox_layout.addWidget(self.use_default_label_checkbox)
        use_default_label_qhbox_layout.addWidget(self.default_label_text_line)
        use_default_label_container = QWidget()
        use_default_label_container.setLayout(use_default_label_qhbox_layout)

        # Create a widget for edit and diffc button
        self.diffc_button = QCheckBox(get_str('useDifficult'))
        self.diffc_button.setChecked(False)
        self.diffc_button.stateChanged.connect(self.button_state)
        self.edit_button = QToolButton()
        self.edit_button.setToolButtonStyle(Qt.ToolButtonTextBesideIcon)

        # Add some of widgets to list_layout
        list_layout.addWidget(self.edit_button)
        list_layout.addWidget(self.diffc_button)
        list_layout.addWidget(use_default_label_container)

        # Create and add combobox for showing unique labels in group
        self.combo_box = ComboBox(self)
        list_layout.addWidget(self.combo_box)

        # Create and add a widget for showing current label items
        self.label_list = QListWidget()
        label_list_container = QWidget()
        label_list_container.setLayout(list_layout)
        self.label_list.itemActivated.connect(self.label_selection_changed)
        self.label_list.itemSelectionChanged.connect(self.label_selection_changed)
        self.label_list.itemDoubleClicked.connect(self.edit_label)
        # Connect to itemChanged to detect checkbox changes.
        self.label_list.itemChanged.connect(self.label_item_changed)
        list_layout.addWidget(self.label_list)

        self.dock = QDockWidget(get_str('boxLabelText'), self)
        self.dock.setObjectName(get_str('labels'))
        self.dock.setWidget(label_list_container)

        self.file_list_widget = QListWidget()
        self.file_list_widget.itemDoubleClicked.connect(self.file_item_double_clicked)
        file_list_layout = QVBoxLayout()
        file_list_layout.setContentsMargins(0, 0, 0, 0)
        file_list_layout.addWidget(self.file_list_widget)
        file_list_container = QWidget()
        file_list_container.setLayout(file_list_layout)
        self.file_dock = QDockWidget(get_str('fileList'), self)
        self.file_dock.setObjectName(get_str('files'))
        self.file_dock.setWidget(file_list_container)

        # speed line dock
        self.speed_curve_fig = plt.figure()
        self.speed_curve_plt = self.speed_curve_fig.add_subplot()
        plt.ion()
        self.speed_curve_fig_canvas = FigureCanvas(self.speed_curve_fig)
        self.speed_curve_dock = QDockWidget(get_str('speedCurve'), self)
        self.speed_curve_dock.setObjectName(get_str('curve'))
        self.speed_curve_dock.setWidget(self.speed_curve_fig_canvas)

        # label batch process dock
        self.batch_export_button = QPushButton(get_str('exportBatch'))
        self.batch_export_button.clicked.connect(self.label_batch_export)
        self.batch_edit_button = QPushButton(get_str('editBatch'))
        self.batch_edit_button.clicked.connect(self.label_batch_edit)
        self.batch_delete_button = QPushButton(get_str('deleteBatch'))
        self.batch_delete_button.clicked.connect(self.label_batch_delete)
        batch_buttons_layout = QHBoxLayout()
        batch_buttons_layout.addWidget(self.batch_export_button)
        batch_buttons_layout.addWidget(self.batch_edit_button)
        batch_buttons_layout.addWidget(self.batch_delete_button)
        batch_buttons_container = QWidget()
        batch_buttons_container.setLayout(batch_buttons_layout)
        self.label_stat_table = QTableWidget()
        self.label_stat_table.setSelectionBehavior(QAbstractItemView.SelectionBehavior.SelectRows)
        self.label_stat_table.setEditTriggers(QAbstractItemView.EditTrigger.NoEditTriggers)
        self.label_stat_table.setColumnCount(2)
        self.label_stat_table.setHorizontalHeaderLabels([get_str('tableHeaderLabel'), get_str('tableHeaderCount')])
        self.label_stat_table.mouseDoubleClickEvent = lambda e: self.label_batch_edit()
        self.label_stat_table.itemSelectionChanged.connect(self.focuse_no_file_with_label)
        label_batch_process_layout = QVBoxLayout()
        label_batch_process_layout.setContentsMargins(0, 0, 0, 0)
        label_batch_process_layout.addWidget(batch_buttons_container)
        label_batch_process_layout.addWidget(self.label_stat_table)
        label_batch_process_container = QWidget()
        label_batch_process_container.setLayout(label_batch_process_layout)
        self.label_batch_precess_dock = QDockWidget(get_str('batchProcess'), self)
        self.label_batch_precess_dock.setObjectName(get_str('batch'))
        self.label_batch_precess_dock.setWidget(label_batch_process_container)

        self.zoom_widget = ZoomWidget()
        self.color_dialog = ColorDialog(parent=self)

        self.canvas = Canvas(parent=self)
        self.canvas.zoomRequest.connect(self.zoom_request)
        self.canvas.set_drawing_shape_to_square(settings.get(SETTING_DRAW_SQUARE, False))

        scroll = QScrollArea()
        scroll.setWidget(self.canvas)
        scroll.setWidgetResizable(True)
        self.scroll_bars = {
            Qt.Vertical: scroll.verticalScrollBar(),
            Qt.Horizontal: scroll.horizontalScrollBar()
        }
        self.scroll_area = scroll
        self.canvas.scrollRequest.connect(self.scroll_request)

        self.canvas.newShape.connect(self.new_shape)
        self.canvas.shapeMoved.connect(self.set_dirty)
        self.canvas.selectionChanged.connect(self.shape_selection_changed)
        self.canvas.drawingPolygon.connect(self.toggle_drawing_sensitive)

        self.setCentralWidget(scroll)
        self.addDockWidget(Qt.RightDockWidgetArea, self.dock)
        self.addDockWidget(Qt.RightDockWidgetArea, self.file_dock)
        self.addDockWidget(Qt.RightDockWidgetArea, self.speed_curve_dock)
        self.addDockWidget(Qt.RightDockWidgetArea, self.label_batch_precess_dock)
        self.tabifyDockWidget(self.dock, self.label_batch_precess_dock)

        self.dock_features = QDockWidget.DockWidgetClosable | QDockWidget.DockWidgetFloatable
        self.dock.setFeatures(self.dock.features() ^ self.dock_features)
        self.file_dock.setFeatures(self.file_dock.features() ^ self.dock_features)
        self.speed_curve_dock.setFeatures(self.speed_curve_dock.features() ^ self.dock_features)
        self.label_batch_precess_dock.setFeatures(self.label_batch_precess_dock.features() ^ self.dock_features)

        # Actions
        action = partial(new_action, self)
        quit = action(get_str('quit'), self.close,
                      'Ctrl+Q', 'quit', get_str('quitApp'))

        open = action(get_str('openFile'), self.open_file,
                      'Ctrl+O', 'open', get_str('openFileDetail'))

        open_dir = action(get_str('openDir'), self.open_dir_dialog,
                          'Ctrl+u', 'open', get_str('openDir'))

        change_save_dir = action(get_str('changeSaveDir'), self.change_save_dir_dialog,
                                 'Ctrl+r', 'open', get_str('changeSavedAnnotationDir'))

        open_annotation = action(get_str('openAnnotation'), self.open_annotation_dialog,
                                 'Ctrl+Shift+O', 'open', get_str('openAnnotationDetail'))
        copy_prev_bounding = action(get_str('copyPrevBounding'), self.copy_previous_bounding_boxes, 'Ctrl+v', 'copy', get_str('copyPrevBounding'))

        open_next_image = action(get_str('nextImg'), self.open_next_image,
                                 'd', 'next', get_str('nextImgDetail'))

        open_prev_image = action(get_str('prevImg'), self.open_prev_image,
                                 'a', 'prev', get_str('prevImgDetail'))

        verify = action(get_str('verifyImg'), self.verify_image,
                        'space', 'verify', get_str('verifyImgDetail'))

        save = action(get_str('save'), self.save_file,
                      'Ctrl+S', 'save', get_str('saveDetail'), enabled=False)

        def get_format_meta(format):
            """
            returns a tuple containing (title, icon_name) of the selected format
            """
            if format == LabelFileFormat.PASCAL_VOC:
                return '&PascalVOC', 'format_voc'
            elif format == LabelFileFormat.YOLO:
                return '&YOLO', 'format_yolo'
            elif format == LabelFileFormat.CREATE_ML:
                return '&CreateML', 'format_createml'

        save_format = action(get_format_meta(self.label_file_format)[0],
                             self.change_format, 'Ctrl+',
                             get_format_meta(self.label_file_format)[1],
                             get_str('changeSaveFormat'), enabled=True)

        save_as = action(get_str('saveAs'), self.save_file_as,
                         'Ctrl+Shift+S', 'save-as', get_str('saveAsDetail'), enabled=False)

        close = action(get_str('closeCur'), self.close_file, 'Ctrl+W', 'close', get_str('closeCurDetail'))

        delete_image = action(get_str('deleteImg'), self.delete_image, 'Ctrl+Shift+D', 'close', get_str('deleteImgDetail'))

        reset_all = action(get_str('resetAll'), self.reset_all, None, 'resetall', get_str('resetAllDetail'))

        color1 = action(get_str('boxLineColor'), self.choose_color1,
                        'Ctrl+L', 'color_line', get_str('boxLineColorDetail'))

        create_mode = action(get_str('crtBox'), self.set_create_mode,
                             'w', 'new', get_str('crtBoxDetail'), enabled=False)
        edit_mode = action(get_str('editBox'), self.set_edit_mode,
                           'Ctrl+J', 'edit', get_str('editBoxDetail'), enabled=False)

        create = action(get_str('crtBox'), self.create_shape,
                        'w', 'new', get_str('crtBoxDetail'), enabled=False)
        delete = action(get_str('delBox'), self.delete_selected_shape,
                        'Delete', 'delete', get_str('delBoxDetail'), enabled=False)
        copy = action(get_str('dupBox'), self.copy_selected_shape,
                      'Ctrl+D', 'copy', get_str('dupBoxDetail'),
                      enabled=False)

        advanced_mode = action(get_str('advancedMode'), self.toggle_advanced_mode,
                               'Ctrl+Shift+A', 'expert', get_str('advancedModeDetail'),
                               checkable=True)

        hide_all = action(get_str('hideAllBox'), partial(self.toggle_polygons, False),
                          'Ctrl+H', 'hide', get_str('hideAllBoxDetail'),
                          enabled=False)
        show_all = action(get_str('showAllBox'), partial(self.toggle_polygons, True),
                          'Ctrl+A', 'hide', get_str('showAllBoxDetail'),
                          enabled=False)

        help_default = action(get_str('tutorialDefault'), self.show_default_tutorial_dialog, None, 'help', get_str('tutorialDetail'))
        show_info = action(get_str('info'), self.show_info_dialog, None, 'help', get_str('info'))
        show_shortcut = action(get_str('shortcut'), self.show_shortcuts_dialog, None, 'help', get_str('shortcut'))

        zoom = QWidgetAction(self)
        zoom.setDefaultWidget(self.zoom_widget)
        self.zoom_widget.setWhatsThis(
            u"Zoom in or out of the image. Also accessible with"
            " %s and %s from the canvas." % (format_shortcut("Ctrl+[-+]"),
                                             format_shortcut("Ctrl+Wheel")))
        self.zoom_widget.setEnabled(False)

        zoom_in = action(get_str('zoomin'), partial(self.add_zoom, 10),
                         'Ctrl++', 'zoom-in', get_str('zoominDetail'), enabled=False)
        zoom_out = action(get_str('zoomout'), partial(self.add_zoom, -10),
                          'Ctrl+-', 'zoom-out', get_str('zoomoutDetail'), enabled=False)
        zoom_org = action(get_str('originalsize'), partial(self.set_zoom, 100),
                          'Ctrl+=', 'zoom', get_str('originalsizeDetail'), enabled=False)
        fit_window = action(get_str('fitWin'), self.set_fit_window,
                            'Ctrl+F', 'fit-window', get_str('fitWinDetail'),
                            checkable=True, enabled=False)
        fit_width = action(get_str('fitWidth'), self.set_fit_width,
                           'Ctrl+Shift+F', 'fit-width', get_str('fitWidthDetail'),
                           checkable=True, enabled=False)
        # Group zoom controls into a list for easier toggling.
        zoom_actions = (self.zoom_widget, zoom_in, zoom_out,
                        zoom_org, fit_window, fit_width)
        self.zoom_mode = self.MANUAL_ZOOM
        self.scalers = {
            self.FIT_WINDOW: self.scale_fit_window,
            self.FIT_WIDTH: self.scale_fit_width,
            # Set to one to scale to 100% when loading files.
            self.MANUAL_ZOOM: lambda: 1,
        }

        edit = action(get_str('editLabel'), self.edit_label,
                      'Ctrl+E', 'edit', get_str('editLabelDetail'),
                      enabled=False)
        self.edit_button.setDefaultAction(edit)

        shape_line_color = action(get_str('shapeLineColor'), self.choose_shape_line_color,
                                  icon='color_line', tip=get_str('shapeLineColorDetail'),
                                  enabled=False)
        shape_fill_color = action(get_str('shapeFillColor'), self.choose_shape_fill_color,
                                  icon='color', tip=get_str('shapeFillColorDetail'),
                                  enabled=False)

        labels = self.dock.toggleViewAction()
        labels.setText(get_str('showHide'))
        labels.setShortcut('Ctrl+Shift+L')

        # Label list context menu.
        label_menu = QMenu()
        add_actions(label_menu, (edit, delete))
        self.label_list.setContextMenuPolicy(Qt.CustomContextMenu)
        self.label_list.customContextMenuRequested.connect(
            self.pop_label_list_menu)

        # Draw squares/rectangles
        self.draw_squares_option = QAction(get_str('drawSquares'), self)
        self.draw_squares_option.setShortcut('Ctrl+Shift+R')
        self.draw_squares_option.setCheckable(True)
        self.draw_squares_option.setChecked(settings.get(SETTING_DRAW_SQUARE, False))
        self.draw_squares_option.triggered.connect(self.toggle_draw_square)

        # Store actions for further handling.
        self.actions = Struct(save=save, save_format=save_format, saveAs=save_as, open=open, close=close, resetAll=reset_all, deleteImg=delete_image,
                              lineColor=color1, create=create, delete=delete, edit=edit, copy=copy,
                              createMode=create_mode, editMode=edit_mode, advancedMode=advanced_mode,
                              shapeLineColor=shape_line_color, shapeFillColor=shape_fill_color,
                              zoom=zoom, zoomIn=zoom_in, zoomOut=zoom_out, zoomOrg=zoom_org,
                              fitWindow=fit_window, fitWidth=fit_width,
                              zoomActions=zoom_actions,
                              fileMenuActions=(
                                  open, open_dir, save, save_as, close, reset_all, quit),
                              beginner=(), advanced=(),
                              editMenu=(edit, copy, delete,
                                        None, color1, self.draw_squares_option),
                              beginnerContext=(create, edit, copy, delete),
                              advancedContext=(create_mode, edit_mode, edit, copy,
                                               delete, shape_line_color, shape_fill_color),
                              onLoadActive=(
                                  close, create, create_mode, edit_mode),
                              onShapesPresent=(save_as, hide_all, show_all))

        self.menus = Struct(
            file=self.menu(get_str('menu_file')),
            edit=self.menu(get_str('menu_edit')),
            view=self.menu(get_str('menu_view')),
            help=self.menu(get_str('menu_help')),
            recentFiles=QMenu(get_str('menu_openRecent')),
            labelList=label_menu)

        # Auto saving : Enable auto saving if pressing next
        self.auto_saving = QAction(get_str('autoSaveMode'), self)
        self.auto_saving.setCheckable(True)
        self.auto_saving.setChecked(settings.get(SETTING_AUTO_SAVE, False))
        # Sync single class mode from PR#106
        self.single_class_mode = QAction(get_str('singleClsMode'), self)
        self.single_class_mode.setShortcut("Ctrl+Shift+S")
        self.single_class_mode.setCheckable(True)
        self.single_class_mode.setChecked(settings.get(SETTING_SINGLE_CLASS, False))
        self.lastLabel = None
        # Add option to enable/disable labels being displayed at the top of bounding boxes
        self.display_label_option = QAction(get_str('displayLabel'), self)
        self.display_label_option.setShortcut("Ctrl+Shift+P")
        self.display_label_option.setCheckable(True)
        self.display_label_option.setChecked(settings.get(SETTING_PAINT_LABEL, False))
        self.display_label_option.triggered.connect(self.toggle_paint_labels_option)

        add_actions(self.menus.file,
                    (open, open_dir, change_save_dir, open_annotation, copy_prev_bounding, self.menus.recentFiles, save, save_format, save_as, close, reset_all, delete_image, quit))
        add_actions(self.menus.help, (help_default, show_info, show_shortcut))
        add_actions(self.menus.view, (
            self.auto_saving,
            self.single_class_mode,
            self.display_label_option,
            labels, advanced_mode, None,
            hide_all, show_all, None,
            zoom_in, zoom_out, zoom_org, None,
            fit_window, fit_width))

        self.menus.file.aboutToShow.connect(self.update_file_menu)

        # Custom context menu for the canvas widget:
        add_actions(self.canvas.menus[0], self.actions.beginnerContext)
        add_actions(self.canvas.menus[1], (
            action('&Copy here', self.copy_shape),
            action('&Move here', self.move_shape)))

        self.tools = self.toolbar('Tools')
        self.actions.beginner = (
            open, open_dir, change_save_dir, open_next_image, open_prev_image, verify, save, save_format, None, create, copy, delete, None,
            zoom_in, zoom, zoom_out, fit_window, fit_width)

        self.actions.advanced = (
            open, open_dir, change_save_dir, open_next_image, open_prev_image, save, save_format, None,
            create_mode, edit_mode, None,
            hide_all, show_all)

        self.statusBar().showMessage('%s started.' % __appname__)
        self.statusBar().show()

        # Application state.
        self.image = QImage()
        self.file_path = ustr(default_filename)
        self.last_open_dir = None
        self.recent_files = []
        self.max_recent = 7
        self.line_color = None
        self.fill_color = None
        self.zoom_level = 100
        self.fit_window = False
        # Add Chris
        self.difficult = False

        # Fix the compatible issue for qt4 and qt5. Convert the QStringList to python list
        if settings.get(SETTING_RECENT_FILES):
            if have_qstring():
                recent_file_qstring_list = settings.get(SETTING_RECENT_FILES)
                self.recent_files = [ustr(i) for i in recent_file_qstring_list]
            else:
                self.recent_files = recent_file_qstring_list = settings.get(SETTING_RECENT_FILES)

        size = settings.get(SETTING_WIN_SIZE, QSize(600, 500))
        position = QPoint(0, 0)
        saved_position = settings.get(SETTING_WIN_POSE, position)
        # Fix the multiple monitors issue
        for i in range(QApplication.desktop().screenCount()):
            if QApplication.desktop().availableGeometry(i).contains(saved_position):
                position = saved_position
                break
        self.resize(size)
        self.move(position)
        save_dir = ustr(settings.get(SETTING_SAVE_DIR, None))
        self.last_open_dir = ustr(settings.get(SETTING_LAST_OPEN_DIR, None))
        if self.default_save_dir is None and save_dir is not None and os.path.exists(save_dir):
            self.default_save_dir = save_dir
            self.statusBar().showMessage('%s started. Annotation will be saved to %s' %
                                         (__appname__, self.default_save_dir))
            self.statusBar().show()

        self.restoreState(settings.get(SETTING_WIN_STATE, QByteArray()))
        Shape.line_color = self.line_color = QColor(settings.get(SETTING_LINE_COLOR, DEFAULT_LINE_COLOR))
        Shape.fill_color = self.fill_color = QColor(settings.get(SETTING_FILL_COLOR, DEFAULT_FILL_COLOR))
        self.canvas.set_drawing_color(self.line_color)
        # Add chris
        Shape.difficult = self.difficult

        def xbool(x):
            if isinstance(x, QVariant):
                return x.toBool()
            return bool(x)

        if xbool(settings.get(SETTING_ADVANCE_MODE, False)):
            self.actions.advancedMode.setChecked(True)
            self.toggle_advanced_mode()

        # Populate the File menu dynamically.
        self.update_file_menu()

        # Since loading the file may take some time, make sure it runs in the background.
        if self.file_path and os.path.isdir(self.file_path):
            self.queue_event(partial(self.import_dir_images, self.file_path or ""))
        elif self.file_path:
            self.queue_event(partial(self.load_file, self.file_path or ""))

        # Callbacks:
        self.zoom_widget.valueChanged.connect(self.paint_canvas)

        self.populate_mode_actions()

        # Display cursor coordinates at the right of status bar
        self.label_coordinates = QLabel('')
        self.statusBar().addPermanentWidget(self.label_coordinates)

        # Open Dir if default file
        if self.file_path and os.path.isdir(self.file_path):
            self.open_dir_dialog(dir_path=self.file_path, silent=True)

    def keyReleaseEvent(self, event):
        if event.key() == Qt.Key_Control:
            self.canvas.set_drawing_shape_to_square(False)

    def keyPressEvent(self, event):
        if event.key() == Qt.Key_Control:
            # Draw rectangle if Ctrl is pressed
            self.canvas.set_drawing_shape_to_square(True)

    # Support Functions #
    def set_format(self, save_format):
        if save_format == FORMAT_PASCALVOC:
            self.actions.save_format.setText(FORMAT_PASCALVOC)
            self.actions.save_format.setIcon(new_icon("format_voc"))
            self.label_file_format = LabelFileFormat.PASCAL_VOC
            LabelFile.suffix = XML_EXT

        elif save_format == FORMAT_YOLO:
            self.actions.save_format.setText(FORMAT_YOLO)
            self.actions.save_format.setIcon(new_icon("format_yolo"))
            self.label_file_format = LabelFileFormat.YOLO
            LabelFile.suffix = TXT_EXT

        elif save_format == FORMAT_CREATEML:
            self.actions.save_format.setText(FORMAT_CREATEML)
            self.actions.save_format.setIcon(new_icon("format_createml"))
            self.label_file_format = LabelFileFormat.CREATE_ML
            LabelFile.suffix = JSON_EXT

    def change_format(self):
        if self.label_file_format == LabelFileFormat.PASCAL_VOC:
            self.set_format(FORMAT_YOLO)
        elif self.label_file_format == LabelFileFormat.YOLO:
            self.set_format(FORMAT_CREATEML)
        elif self.label_file_format == LabelFileFormat.CREATE_ML:
            self.set_format(FORMAT_PASCALVOC)
        else:
            raise ValueError('Unknown label file format.')
        self.set_dirty()

    def no_shapes(self):
        return not self.items_to_shapes

    def toggle_advanced_mode(self, value=True):
        self._beginner = not value
        self.canvas.set_editing(True)
        self.populate_mode_actions()
        self.edit_button.setVisible(not value)
        if value:
            self.actions.createMode.setEnabled(True)
            self.actions.editMode.setEnabled(False)
            self.dock.setFeatures(self.dock.features() | self.dock_features)
        else:
            self.dock.setFeatures(self.dock.features() ^ self.dock_features)

    def populate_mode_actions(self):
        if self.beginner():
            tool, menu = self.actions.beginner, self.actions.beginnerContext
        else:
            tool, menu = self.actions.advanced, self.actions.advancedContext
        self.tools.clear()
        add_actions(self.tools, tool)
        self.canvas.menus[0].clear()
        add_actions(self.canvas.menus[0], menu)
        self.menus.edit.clear()
        actions = (self.actions.create,) if self.beginner()\
            else (self.actions.createMode, self.actions.editMode)
        add_actions(self.menus.edit, actions + self.actions.editMenu)

    def set_beginner(self):
        self.tools.clear()
        add_actions(self.tools, self.actions.beginner)

    def set_advanced(self):
        self.tools.clear()
        add_actions(self.tools, self.actions.advanced)

    def set_dirty(self):
        self.dirty = True
        self.actions.save.setEnabled(True)

    def set_clean(self):
        self.dirty = False
        self.actions.save.setEnabled(False)
        self.actions.create.setEnabled(True)

    def toggle_actions(self, value=True):
        """Enable/Disable widgets which depend on an opened image."""
        for z in self.actions.zoomActions:
            z.setEnabled(value)
        for action in self.actions.onLoadActive:
            action.setEnabled(value)

    def queue_event(self, function):
        QTimer.singleShot(0, function)

    def status(self, message, delay=5000):
        self.statusBar().showMessage(message, delay)

    def reset_state(self):
        self.items_to_shapes.clear()
        self.shapes_to_items.clear()
        self.label_list.clear()
        self.file_path = None
        self.image_data = None
        self.label_file = None
        self.canvas.reset_state()
        self.label_coordinates.clear()
        self.combo_box.cb.clear()

    def current_item(self):
        items = self.label_list.selectedItems()
        if items:
            return items[0]
        return None

    def add_recent_file(self, file_path):
        if file_path in self.recent_files:
            self.recent_files.remove(file_path)
        elif len(self.recent_files) >= self.max_recent:
            self.recent_files.pop()
        self.recent_files.insert(0, file_path)

    def beginner(self):
        return self._beginner

    def advanced(self):
        return not self.beginner()

    def show_tutorial_dialog(self, browser='default', link=None):
        if link is None:
            link = self.screencast

        if browser.lower() == 'default':
            wb.open(link, new=2)
        elif browser.lower() == 'chrome' and self.os_name == 'Windows':
            if shutil.which(browser.lower()):  # 'chrome' not in wb._browsers in windows
                wb.register('chrome', None, wb.BackgroundBrowser('chrome'))
            else:
                chrome_path="D:\\Program Files (x86)\\Google\\Chrome\\Application\\chrome.exe"
                if os.path.isfile(chrome_path):
                    wb.register('chrome', None, wb.BackgroundBrowser(chrome_path))
            try:
                wb.get('chrome').open(link, new=2)
            except:
                wb.open(link, new=2)
        elif browser.lower() in wb._browsers:
            wb.get(browser.lower()).open(link, new=2)

    def show_default_tutorial_dialog(self):
        self.show_tutorial_dialog(browser='default')

    def show_info_dialog(self):
        from libs.__init__ import __version__
        msg = u'Name:{0} \nApp Version:{1} \n{2} '.format(__appname__, __version__, sys.version_info)
        QMessageBox.information(self, u'Information', msg)

    def show_shortcuts_dialog(self):
        self.show_tutorial_dialog(browser='default', link='https://github.com/tzutalin/labelImg#Hotkeys')

    def create_shape(self):
        assert self.beginner()
        self.canvas.set_editing(False)
        self.actions.create.setEnabled(False)

    def toggle_drawing_sensitive(self, drawing=True):
        """In the middle of drawing, toggling between modes should be disabled."""
        self.actions.editMode.setEnabled(not drawing)
        if not drawing and self.beginner():
            # Cancel creation.
            print('Cancel creation.')
            self.canvas.set_editing(True)
            self.canvas.restore_cursor()
            self.actions.create.setEnabled(True)

    def toggle_draw_mode(self, edit=True):
        self.canvas.set_editing(edit)
        self.actions.createMode.setEnabled(edit)
        self.actions.editMode.setEnabled(not edit)

    def set_create_mode(self):
        assert self.advanced()
        self.toggle_draw_mode(False)

    def set_edit_mode(self):
        assert self.advanced()
        self.toggle_draw_mode(True)
        self.label_selection_changed()

    def update_file_menu(self):
        curr_file_path = self.file_path

        def exists(filename):
            return os.path.exists(filename)
        menu = self.menus.recentFiles
        menu.clear()
        files = [f for f in self.recent_files if f !=
                 curr_file_path and exists(f)]
        for i, f in enumerate(files):
            icon = new_icon('labels')
            action = QAction(
                icon, '&%d %s' % (i + 1, QFileInfo(f).fileName()), self)
            action.triggered.connect(partial(self.load_recent, f))
            menu.addAction(action)

    def pop_label_list_menu(self, point):
        self.menus.labelList.exec_(self.label_list.mapToGlobal(point))

    def edit_label(self):
        if not self.canvas.editing():
            return
        item = self.current_item()
        if not item:
            return
        text = self.label_dialog.pop_up(item.text())
        if text is not None:
            item.setText(text)
            item.setBackground(generate_color_by_text(text))
            self.set_dirty()
            self.update_combo_box()

    # Tzutalin 20160906 : Add file list and dock to move faster
    def file_item_double_clicked(self, item=None):
        self.cur_img_idx = self.m_img_list.index(ustr(item.text()))
        filename = self.m_img_list[self.cur_img_idx]
        if filename:
            self.load_file(filename)

    # Add chris
    def button_state(self, item=None):
        """ Function to handle difficult examples
        Update on each object """
        if not self.canvas.editing():
            return

        item = self.current_item()
        if not item:  # If not selected Item, take the first one
            item = self.label_list.item(self.label_list.count() - 1)

        difficult = self.diffc_button.isChecked()

        try:
            shape = self.items_to_shapes[item]
        except:
            pass
        # Checked and Update
        try:
            if difficult != shape.difficult:
                shape.difficult = difficult
                self.set_dirty()
            else:  # User probably changed item visibility
                self.canvas.set_shape_visible(shape, item.checkState() == Qt.Checked)
        except:
            pass

    # React to canvas signals.
    def shape_selection_changed(self, selected=False):
        if self._no_selection_slot:
            self._no_selection_slot = False
        else:
            shape = self.canvas.selected_shape
            if shape:
                self.shapes_to_items[shape].setSelected(True)
            else:
                self.label_list.clearSelection()
        self.actions.delete.setEnabled(selected)
        self.actions.copy.setEnabled(selected)
        self.actions.edit.setEnabled(selected)
        self.actions.shapeLineColor.setEnabled(selected)
        self.actions.shapeFillColor.setEnabled(selected)

    def add_label(self, shape):
        shape.paint_label = self.display_label_option.isChecked()
        item = HashableQListWidgetItem(shape.label)
        item.setFlags(item.flags() | Qt.ItemIsUserCheckable)
        item.setCheckState(Qt.Checked)
        item.setBackground(generate_color_by_text(shape.label))
        self.items_to_shapes[item] = shape
        self.shapes_to_items[shape] = item
        self.label_list.addItem(item)
        for action in self.actions.onShapesPresent:
            action.setEnabled(True)
        self.update_combo_box()

    def remove_label(self, shape):
        if shape is None:
            # print('rm empty label')
            return
        item = self.shapes_to_items[shape]
        self.label_list.takeItem(self.label_list.row(item))
        del self.shapes_to_items[shape]
        del self.items_to_shapes[item]
        self.update_combo_box()

    def load_labels(self, shapes):
        s = []
        for label, points, line_color, fill_color, difficult in shapes:
            shape = Shape(label=label)
            for x, y in points:

                # Ensure the labels are within the bounds of the image. If not, fix them.
                x, y, snapped = self.canvas.snap_point_to_canvas(x, y)
                if snapped:
                    self.set_dirty()

                shape.add_point(QPointF(x, y))
            shape.difficult = difficult
            shape.close()
            s.append(shape)

            if line_color:
                shape.line_color = QColor(*line_color)
            else:
                shape.line_color = generate_color_by_text(label)

            if fill_color:
                shape.fill_color = QColor(*fill_color)
            else:
                shape.fill_color = generate_color_by_text(label)

            self.add_label(shape)
        self.update_combo_box()
        self.canvas.load_shapes(s)

    def update_combo_box(self):
        # Get the unique labels and add them to the Combobox.
        items_text_list = [str(self.label_list.item(i).text()) for i in range(self.label_list.count())]

        unique_text_list = list(set(items_text_list))
        # Add a null row for showing all the labels
        unique_text_list.append("")
        unique_text_list.sort()

        self.combo_box.update_items(unique_text_list)

    def save_labels(self, annotation_file_path):
        annotation_file_path = ustr(annotation_file_path)
        if self.label_file is None:
            self.label_file = LabelFile()
            self.label_file.verified = self.canvas.verified

        def format_shape(s):
            return dict(label=s.label,
                        line_color=s.line_color.getRgb(),
                        fill_color=s.fill_color.getRgb(),
                        points=[(p.x(), p.y()) for p in s.points],
                        # add chris
                        difficult=s.difficult)

        shapes = [format_shape(shape) for shape in self.canvas.shapes]
        # Can add different annotation formats here
        try:
            if self.label_file_format == LabelFileFormat.PASCAL_VOC:
                if annotation_file_path[-4:].lower() != ".xml":
                    annotation_file_path += XML_EXT
                self.label_file.save_pascal_voc_format(annotation_file_path, shapes, self.file_path, self.image_data,
                                                       self.line_color.getRgb(), self.fill_color.getRgb())
            elif self.label_file_format == LabelFileFormat.YOLO:
                if annotation_file_path[-4:].lower() != ".txt":
                    annotation_file_path += TXT_EXT
                self.label_file.save_yolo_format(annotation_file_path, shapes, self.file_path, self.image_data, self.label_hist,
                                                 self.line_color.getRgb(), self.fill_color.getRgb())
            elif self.label_file_format == LabelFileFormat.CREATE_ML:
                if annotation_file_path[-5:].lower() != ".json":
                    annotation_file_path += JSON_EXT
                self.label_file.save_create_ml_format(annotation_file_path, shapes, self.file_path, self.image_data,
                                                      self.label_hist, self.line_color.getRgb(), self.fill_color.getRgb())
            else:
                self.label_file.save(annotation_file_path, shapes, self.file_path, self.image_data,
                                     self.line_color.getRgb(), self.fill_color.getRgb())
            print('Image:{0} -> Annotation:{1}'.format(self.file_path, annotation_file_path))
            return True
        except LabelFileError as e:
            self.error_message(u'Error saving label data', u'<b>%s</b>' % e)
            return False

    def copy_selected_shape(self):
        self.add_label(self.canvas.copy_selected_shape())
        # fix copy and delete
        self.shape_selection_changed(True)

    def combo_selection_changed(self, index):
        text = self.combo_box.cb.itemText(index)
        for i in range(self.label_list.count()):
            if text == "":
                self.label_list.item(i).setCheckState(2)
            elif text != self.label_list.item(i).text():
                self.label_list.item(i).setCheckState(0)
            else:
                self.label_list.item(i).setCheckState(2)

    def label_selection_changed(self):
        item = self.current_item()
        if item and self.canvas.editing():
            self._no_selection_slot = True
            self.canvas.select_shape(self.items_to_shapes[item])
            shape = self.items_to_shapes[item]
            # Add Chris
            self.diffc_button.setChecked(shape.difficult)

    def label_item_changed(self, item):
        shape = self.items_to_shapes[item]
        label = item.text()
        if label != shape.label:
            shape.label = item.text()
            shape.line_color = generate_color_by_text(shape.label)
            self.set_dirty()
        else:  # User probably changed item visibility
            self.canvas.set_shape_visible(shape, item.checkState() == Qt.Checked)

    # Callback functions:
    def new_shape(self):
        """Pop-up and give focus to the label editor.

        position MUST be in global coordinates.
        """
        if not self.use_default_label_checkbox.isChecked() or not self.default_label_text_line.text():
            if len(self.label_hist) > 0:
                self.label_dialog = LabelDialog(
                    parent=self, list_item=self.label_hist)

            # Sync single class mode from PR#106
            if self.single_class_mode.isChecked() and self.lastLabel:
                text = self.lastLabel
            else:
                text = self.label_dialog.pop_up(text=self.prev_label_text)
                self.lastLabel = text
        else:
            text = self.default_label_text_line.text()

        # Add Chris
        self.diffc_button.setChecked(False)
        if text is not None:
            self.prev_label_text = text
            generate_color = generate_color_by_text(text)
            shape = self.canvas.set_last_label(text, generate_color, generate_color)
            self.add_label(shape)
            if self.beginner():  # Switch to edit mode.
                self.canvas.set_editing(True)
                self.actions.create.setEnabled(True)
            else:
                self.actions.editMode.setEnabled(True)
            self.set_dirty()

            if text not in self.label_hist:
                self.label_hist.append(text)
        else:
            # self.canvas.undoLastLine()
            self.canvas.reset_all_lines()

    def scroll_request(self, delta, orientation):
        units = - delta / (8 * 15)
        bar = self.scroll_bars[orientation]
        bar.setValue(bar.value() + bar.singleStep() * units)

    def set_zoom(self, value):
        self.actions.fitWidth.setChecked(False)
        self.actions.fitWindow.setChecked(False)
        self.zoom_mode = self.MANUAL_ZOOM
        self.zoom_widget.setValue(value)

    def add_zoom(self, increment=10):
        self.set_zoom(self.zoom_widget.value() + increment)

    def zoom_request(self, delta):
        # get the current scrollbar positions
        # calculate the percentages ~ coordinates
        h_bar = self.scroll_bars[Qt.Horizontal]
        v_bar = self.scroll_bars[Qt.Vertical]

        # get the current maximum, to know the difference after zooming
        h_bar_max = h_bar.maximum()
        v_bar_max = v_bar.maximum()

        # get the cursor position and canvas size
        # calculate the desired movement from 0 to 1
        # where 0 = move left
        #       1 = move right
        # up and down analogous
        cursor = QCursor()
        pos = cursor.pos()
        relative_pos = QWidget.mapFromGlobal(self, pos)

        cursor_x = relative_pos.x()
        cursor_y = relative_pos.y()

        w = self.scroll_area.width()
        h = self.scroll_area.height()

        # the scaling from 0 to 1 has some padding
        # you don't have to hit the very leftmost pixel for a maximum-left movement
        margin = 0.1
        move_x = (cursor_x - margin * w) / (w - 2 * margin * w)
        move_y = (cursor_y - margin * h) / (h - 2 * margin * h)

        # clamp the values from 0 to 1
        move_x = min(max(move_x, 0), 1)
        move_y = min(max(move_y, 0), 1)

        # zoom in
        units = delta / (8 * 15)
        scale = 10
        self.add_zoom(scale * units)

        # get the difference in scrollbar values
        # this is how far we can move
        d_h_bar_max = h_bar.maximum() - h_bar_max
        d_v_bar_max = v_bar.maximum() - v_bar_max

        # get the new scrollbar values
        new_h_bar_value = h_bar.value() + move_x * d_h_bar_max
        new_v_bar_value = v_bar.value() + move_y * d_v_bar_max

        h_bar.setValue(new_h_bar_value)
        v_bar.setValue(new_v_bar_value)

    def set_fit_window(self, value=True):
        if value:
            self.actions.fitWidth.setChecked(False)
        self.zoom_mode = self.FIT_WINDOW if value else self.MANUAL_ZOOM
        self.adjust_scale()

    def set_fit_width(self, value=True):
        if value:
            self.actions.fitWindow.setChecked(False)
        self.zoom_mode = self.FIT_WIDTH if value else self.MANUAL_ZOOM
        self.adjust_scale()

    def toggle_polygons(self, value):
        for item, shape in self.items_to_shapes.items():
            item.setCheckState(Qt.Checked if value else Qt.Unchecked)

    def load_file(self, file_path=None):
        """Load the specified file, or the last opened file if None."""
        self.reset_state()
        self.canvas.setEnabled(False)
        if file_path is None:
            file_path = self.settings.get(SETTING_FILENAME)

        # Make sure that filePath is a regular python string, rather than QString
        file_path = ustr(file_path)

        # Fix bug: An  index error after select a directory when open a new file.
        unicode_file_path = ustr(file_path)
        unicode_file_path = os.path.abspath(unicode_file_path)
        # Tzutalin 20160906 : Add file list and dock to move faster
        # Highlight the file item
        if unicode_file_path and self.file_list_widget.count() > 0:
            if unicode_file_path in self.m_img_list:
                index = self.m_img_list.index(unicode_file_path)
                file_widget_item = self.file_list_widget.item(index)
                file_widget_item.setSelected(True)
            else:
                self.file_list_widget.clear()
                self.m_img_list.clear()

        if unicode_file_path and os.path.exists(unicode_file_path):
            if LabelFile.is_label_file(unicode_file_path):
                try:
                    self.label_file = LabelFile(unicode_file_path)
                except LabelFileError as e:
                    self.error_message(u'Error opening file',
                                       (u"<p><b>%s</b></p>"
                                        u"<p>Make sure <i>%s</i> is a valid label file.")
                                       % (e, unicode_file_path))
                    self.status("Error reading %s" % unicode_file_path)
                    return False
                self.image_data = self.label_file.image_data
                self.line_color = QColor(*self.label_file.lineColor)
                self.fill_color = QColor(*self.label_file.fillColor)
                self.canvas.verified = self.label_file.verified
            else:
                # Load image:
                # read data first and store for saving into label file.
                self.image_data = read(unicode_file_path, None)
                self.label_file = None
                self.canvas.verified = False

            if isinstance(self.image_data, QImage):
                image = self.image_data
            else:
                image = QImage.fromData(self.image_data)
            if image.isNull():
                self.error_message(u'Error opening file',
                                   u"<p>Make sure <i>%s</i> is a valid image file." % unicode_file_path)
                self.status("Error reading %s" % unicode_file_path)
                return False
            self.status("Loaded %s" % os.path.basename(unicode_file_path))
            self.image = image
            self.file_path = unicode_file_path
            self.canvas.load_pixmap(QPixmap.fromImage(image))
            if self.label_file:
                self.load_labels(self.label_file.shapes)
            self.set_clean()
            self.canvas.setEnabled(True)
            self.adjust_scale(initial=True)
            self.paint_canvas()
            self.add_recent_file(self.file_path)
            self.toggle_actions(True)
            self.show_bounding_box_from_annotation_file(file_path)

            counter = self.counter_str()
            self.setWindowTitle(__appname__ + ' ' + file_path + ' ' + counter)

            # Default : select last item if there is at least one item
            if self.label_list.count():
                self.label_list.setCurrentItem(self.label_list.item(self.label_list.count() - 1))
                self.label_list.item(self.label_list.count() - 1).setSelected(True)

            self.canvas.setFocus(True)
            return True
        return False

    def counter_str(self):
        """
        Converts image counter to string representation.
        """
        return '[{} / {}]'.format(self.cur_img_idx + 1, self.img_count)

    def show_bounding_box_from_annotation_file(self, file_path):
        if self.default_save_dir is not None:
            basename = os.path.basename(os.path.splitext(file_path)[0])
            xml_path = os.path.join(self.default_save_dir, basename + XML_EXT)
            txt_path = os.path.join(self.default_save_dir, basename + TXT_EXT)
            json_path = os.path.join(self.default_save_dir, basename + JSON_EXT)

            """Annotation file priority:
            PascalXML > YOLO
            """
            if os.path.isfile(xml_path):
                self.load_pascal_xml_by_filename(xml_path)
            elif os.path.isfile(txt_path):
                self.load_yolo_txt_by_filename(txt_path)
            elif os.path.isfile(json_path):
                self.load_create_ml_json_by_filename(json_path, file_path)

        else:
            xml_path = os.path.splitext(file_path)[0] + XML_EXT
            txt_path = os.path.splitext(file_path)[0] + TXT_EXT
            if os.path.isfile(xml_path):
                self.load_pascal_xml_by_filename(xml_path)
            elif os.path.isfile(txt_path):
                self.load_yolo_txt_by_filename(txt_path)

    def resizeEvent(self, event):
        if self.canvas and not self.image.isNull()\
           and self.zoom_mode != self.MANUAL_ZOOM:
            self.adjust_scale()
        super(MainWindow, self).resizeEvent(event)

    def paint_canvas(self):
        assert not self.image.isNull(), "cannot paint null image"
        self.canvas.scale = 0.01 * self.zoom_widget.value()
        self.canvas.label_font_size = int(0.02 * max(self.image.width(), self.image.height()))
        self.canvas.adjustSize()
        self.canvas.update()

    def adjust_scale(self, initial=False):
        value = self.scalers[self.FIT_WINDOW if initial else self.zoom_mode]()
        self.zoom_widget.setValue(int(100 * value))

    def scale_fit_window(self):
        """Figure out the size of the pixmap in order to fit the main widget."""
        e = 2.0  # So that no scrollbars are generated.
        w1 = self.centralWidget().width() - e
        h1 = self.centralWidget().height() - e
        a1 = w1 / h1
        # Calculate a new scale value based on the pixmap's aspect ratio.
        w2 = self.canvas.pixmap.width() - 0.0
        h2 = self.canvas.pixmap.height() - 0.0
        a2 = w2 / h2
        return w1 / w2 if a2 >= a1 else h1 / h2

    def scale_fit_width(self):
        # The epsilon does not seem to work too well here.
        w = self.centralWidget().width() - 2.0
        return w / self.canvas.pixmap.width()

    def closeEvent(self, event):
        if not self.may_continue():
            event.ignore()
        settings = self.settings
        # If it loads images from dir, don't load it at the beginning
        if self.dir_name is None:
            settings[SETTING_FILENAME] = self.file_path if self.file_path else ''
        else:
            settings[SETTING_FILENAME] = ''

        settings[SETTING_WIN_SIZE] = self.size()
        settings[SETTING_WIN_POSE] = self.pos()
        settings[SETTING_WIN_STATE] = self.saveState()
        settings[SETTING_LINE_COLOR] = self.line_color
        settings[SETTING_FILL_COLOR] = self.fill_color
        settings[SETTING_RECENT_FILES] = self.recent_files
        settings[SETTING_ADVANCE_MODE] = not self._beginner
        if self.default_save_dir and os.path.exists(self.default_save_dir):
            settings[SETTING_SAVE_DIR] = ustr(self.default_save_dir)
        else:
            settings[SETTING_SAVE_DIR] = ''

        if self.last_open_dir and os.path.exists(self.last_open_dir):
            settings[SETTING_LAST_OPEN_DIR] = self.last_open_dir
        else:
            settings[SETTING_LAST_OPEN_DIR] = ''

        settings[SETTING_AUTO_SAVE] = self.auto_saving.isChecked()
        settings[SETTING_SINGLE_CLASS] = self.single_class_mode.isChecked()
        settings[SETTING_PAINT_LABEL] = self.display_label_option.isChecked()
        settings[SETTING_DRAW_SQUARE] = self.draw_squares_option.isChecked()
        settings[SETTING_LABEL_FILE_FORMAT] = self.label_file_format
        settings.save()

    def load_recent(self, filename):
        if self.may_continue():
            self.load_file(filename)

    def scan_all_images(self, folder_path):
        extensions = ['.%s' % fmt.data().decode("ascii").lower() for fmt in QImageReader.supportedImageFormats()]
        images = []

        for root, dirs, files in os.walk(folder_path):
            for file in files:
                if file.lower().endswith(tuple(extensions)):
                    relative_path = os.path.join(root, file)
                    path = ustr(os.path.abspath(relative_path))
                    images.append(path)
        natural_sort(images, key=lambda x: x.lower())
        return images

    def change_save_dir_dialog(self, _value=False):
        if self.default_save_dir is not None:
            path = ustr(self.default_save_dir)
        else:
            path = '.'

        dir_path = ustr(QFileDialog.getExistingDirectory(self,
                                                         '%s - Save annotations to the directory' % __appname__, path,  QFileDialog.ShowDirsOnly
                                                         | QFileDialog.DontResolveSymlinks))

        if dir_path is not None and len(dir_path) > 1:
            self.default_save_dir = dir_path
            self.label_watcher()

        self.statusBar().showMessage('%s . Annotation will be saved to %s' %
                                     ('Change saved folder', self.default_save_dir))
        self.statusBar().show()

    def open_annotation_dialog(self, _value=False):
        if self.file_path is None:
            self.statusBar().showMessage('Please select image first')
            self.statusBar().show()
            return

        path = os.path.dirname(ustr(self.file_path))\
            if self.file_path else '.'
        if self.label_file_format == LabelFileFormat.PASCAL_VOC:
            filters = "Open Annotation XML file (%s)" % ' '.join(['*.xml'])
            filename = ustr(QFileDialog.getOpenFileName(self, '%s - Choose a xml file' % __appname__, path, filters))
            if filename:
                if isinstance(filename, (tuple, list)):
                    filename = filename[0]
            self.load_pascal_xml_by_filename(filename)

    def open_dir_dialog(self, _value=False, dir_path=None, silent=False):
        if not self.may_continue():
            return

        default_open_dir_path = dir_path if dir_path else '.'
        if self.last_open_dir and os.path.exists(self.last_open_dir):
            default_open_dir_path = self.last_open_dir
        else:
            default_open_dir_path = os.path.dirname(self.file_path) if self.file_path else '.'
        if silent != True:
            target_dir_path = ustr(QFileDialog.getExistingDirectory(self,
                                                                    '%s - Open Directory' % __appname__, default_open_dir_path,
                                                                    QFileDialog.ShowDirsOnly | QFileDialog.DontResolveSymlinks))
        else:
            target_dir_path = ustr(default_open_dir_path)
        self.last_open_dir = os.path.normpath(target_dir_path)
        self.import_dir_images(target_dir_path)
        # Fresh static information
        self.label_watcher()

    def import_dir_images(self, dir_path):
        if not self.may_continue() or not dir_path:
            return
        self.last_open_dir = os.path.normpath(dir_path)
        self.dir_name = dir_path
        self.file_path = None
        self.file_list_widget.clear()
        self.m_img_list = self.scan_all_images(dir_path)
        self.img_count = len(self.m_img_list)
        self.open_next_image()
        for imgPath in self.m_img_list:
            item = QListWidgetItem(imgPath)
            self.file_list_widget.addItem(item)

    def import_file_list_images(self, file_list):
        self.file_list_widget.clear()
        self.m_img_list = file_list
        self.img_count = len(self.m_img_list)
        self.open_next_image()
        for imgPath in self.m_img_list:
            item = QListWidgetItem(imgPath)
            self.file_list_widget.addItem(item)

    def focuse_no_file_with_label(self):
        items = [self.label_stat_table.item(i, 0) for i in range(self.label_stat_table.rowCount())]
        items = set(i.text() for i in items)
        selected = self.label_stat_table.selectedItems()[::2]
        selected = set(i.text() for i in selected)
        if selected:
            # got xml filename list with target label
            file_list = search_file_with_label(self.default_save_dir, *selected)
            file_list = ["".join(file.split(".")[:-1]) for file in file_list] # split suffix
            # change to image filepath list
            image_file_list = []
            for image_file in os.listdir(self.last_open_dir):
                if "".join(image_file.split(".")[:-1]) in file_list:
                    image_file_list.append(os.path.join(self.last_open_dir, image_file))
            self.import_file_list_images(image_file_list)
        else:
            self.import_dir_images(self.last_open_dir)


    def verify_image(self, _value=False):
        # Proceeding next image without dialog if having any label
        if self.file_path is not None:
            try:
                self.label_file.toggle_verify()
            except AttributeError:
                # If the labelling file does not exist yet, create if and
                # re-save it with the verified attribute.
                self.save_file()
                if self.label_file is not None:
                    self.label_file.toggle_verify()
                else:
                    return

            self.canvas.verified = self.label_file.verified
            self.paint_canvas()
            self.save_file()

    def open_prev_image(self, _value=False):
        # Proceeding prev image without dialog if having any label
        if self.auto_saving.isChecked():
            if self.default_save_dir is not None:
                if self.dirty is True:
                    self.save_file()
            else:
                self.change_save_dir_dialog()
                return

        if not self.may_continue():
            return

        if self.img_count <= 0:
            return

        if self.file_path is None:
            return

        if self.cur_img_idx - 1 >= 0:
            self.cur_img_idx -= 1
            filename = self.m_img_list[self.cur_img_idx]
            if filename:
                self.load_file(filename)

    def open_next_image(self, _value=False):
        # Proceeding prev image without dialog if having any label
        if self.auto_saving.isChecked():
            if self.default_save_dir is not None:
                if self.dirty is True:
                    self.save_file()
            else:
                self.change_save_dir_dialog()
                return

        if not self.may_continue():
            return

        if self.img_count <= 0:
            return

        filename = None
        if self.file_path is None:
            filename = self.m_img_list[0]
            self.cur_img_idx = 0
        else:
            if self.cur_img_idx + 1 < self.img_count:
                self.cur_img_idx += 1
                filename = self.m_img_list[self.cur_img_idx]

        if filename:
            self.load_file(filename)

    def open_file(self, _value=False):
        if not self.may_continue():
            return
        path = os.path.dirname(ustr(self.file_path)) if self.file_path else '.'
        formats = ['*.%s' % fmt.data().decode("ascii").lower() for fmt in QImageReader.supportedImageFormats()]
        filters = "Image & Label files (%s)" % ' '.join(formats + ['*%s' % LabelFile.suffix])
        filename = QFileDialog.getOpenFileName(self, '%s - Choose Image or Label file' % __appname__, path, filters)
        if filename:
            if isinstance(filename, (tuple, list)):
                filename = filename[0]
            self.cur_img_idx = 0
            self.img_count = 1
            self.load_file(filename)

    def save_file(self, _value=False):
        if self.default_save_dir is not None and len(ustr(self.default_save_dir)):
            if self.file_path:
                image_file_name = os.path.basename(self.file_path)
                saved_file_name = os.path.splitext(image_file_name)[0]
                saved_path = os.path.join(ustr(self.default_save_dir), saved_file_name)
                self._save_file(saved_path)
        else:
            image_file_dir = os.path.dirname(self.file_path)
            image_file_name = os.path.basename(self.file_path)
            saved_file_name = os.path.splitext(image_file_name)[0]
            saved_path = os.path.join(image_file_dir, saved_file_name)
            self._save_file(saved_path if self.label_file
                            else self.save_file_dialog(remove_ext=False))

    def save_file_as(self, _value=False):
        assert not self.image.isNull(), "cannot save empty image"
        self._save_file(self.save_file_dialog())

    def save_file_dialog(self, remove_ext=True):
        caption = '%s - Choose File' % __appname__
        filters = 'File (*%s)' % LabelFile.suffix
        open_dialog_path = self.current_path()
        dlg = QFileDialog(self, caption, open_dialog_path, filters)
        dlg.setDefaultSuffix(LabelFile.suffix[1:])
        dlg.setAcceptMode(QFileDialog.AcceptSave)
        filename_without_extension = os.path.splitext(self.file_path)[0]
        dlg.selectFile(filename_without_extension)
        dlg.setOption(QFileDialog.DontUseNativeDialog, False)
        if dlg.exec_():
            full_file_path = ustr(dlg.selectedFiles()[0])
            if remove_ext:
                return os.path.splitext(full_file_path)[0]  # Return file path without the extension.
            else:
                return full_file_path
        return ''

    def _save_file(self, annotation_file_path):
        if annotation_file_path and self.save_labels(annotation_file_path):
            self.set_clean()
            self.statusBar().showMessage('Saved to  %s' % annotation_file_path)
            self.statusBar().show()
            # statics information
            self.label_watcher()
            self.file_watcher()

    def close_file(self, _value=False):
        if not self.may_continue():
            return
        self.reset_state()
        self.set_clean()
        self.toggle_actions(False)
        self.canvas.setEnabled(False)
        self.actions.saveAs.setEnabled(False)

    def delete_image(self):
        delete_path = self.file_path
        if delete_path is not None:
            self.open_next_image()
            self.cur_img_idx -= 1
            self.img_count -= 1
            if os.path.exists(delete_path):
                os.remove(delete_path)
            self.import_dir_images(self.last_open_dir)

    def reset_all(self):
        self.settings.reset()
        self.close()
        process = QProcess()
        process.startDetached(os.path.abspath(__file__))

    def may_continue(self):
        if not self.dirty:
            return True
        else:
            discard_changes = self.discard_changes_dialog()
            if discard_changes == QMessageBox.No:
                return True
            elif discard_changes == QMessageBox.Yes:
                self.save_file()
                return True
            else:
                return False

    def discard_changes_dialog(self):
        yes, no, cancel = QMessageBox.Yes, QMessageBox.No, QMessageBox.Cancel
        msg = u'You have unsaved changes, would you like to save them and proceed?\nClick "No" to undo all changes.'
        return QMessageBox.warning(self, u'Attention', msg, yes | no | cancel)

    def error_message(self, title, message):
        return QMessageBox.critical(self, title,
                                    '<p><b>%s</b></p>%s' % (title, message))

    def current_path(self):
        return os.path.dirname(self.file_path) if self.file_path else '.'

    def choose_color1(self):
        color = self.color_dialog.getColor(self.line_color, u'Choose line color',
                                           default=DEFAULT_LINE_COLOR)
        if color:
            self.line_color = color
            Shape.line_color = color
            self.canvas.set_drawing_color(color)
            self.canvas.update()
            self.set_dirty()

    def delete_selected_shape(self):
        self.remove_label(self.canvas.delete_selected())
        self.set_dirty()
        if self.no_shapes():
            for action in self.actions.onShapesPresent:
                action.setEnabled(False)

    def choose_shape_line_color(self):
        color = self.color_dialog.getColor(self.line_color, u'Choose Line Color',
                                           default=DEFAULT_LINE_COLOR)
        if color:
            self.canvas.selected_shape.line_color = color
            self.canvas.update()
            self.set_dirty()

    def choose_shape_fill_color(self):
        color = self.color_dialog.getColor(self.fill_color, u'Choose Fill Color',
                                           default=DEFAULT_FILL_COLOR)
        if color:
            self.canvas.selected_shape.fill_color = color
            self.canvas.update()
            self.set_dirty()

    def copy_shape(self):
        self.canvas.end_move(copy=True)
        self.add_label(self.canvas.selected_shape)
        self.set_dirty()

    def move_shape(self):
        self.canvas.end_move(copy=False)
        self.set_dirty()

    def load_predefined_classes(self, predef_classes_file):
        if os.path.exists(predef_classes_file) is True:
            with codecs.open(predef_classes_file, 'r', 'utf8') as f:
                for line in f:
                    line = line.strip()
                    if self.label_hist is None:
                        self.label_hist = [line]
                    else:
                        self.label_hist.append(line)

    def load_pascal_xml_by_filename(self, xml_path):
        if self.file_path is None:
            return
        if os.path.isfile(xml_path) is False:
            return

        self.set_format(FORMAT_PASCALVOC)

        t_voc_parse_reader = PascalVocReader(xml_path)
        shapes = t_voc_parse_reader.get_shapes()
        self.load_labels(shapes)
        self.canvas.verified = t_voc_parse_reader.verified

    def load_yolo_txt_by_filename(self, txt_path):
        if self.file_path is None:
            return
        if os.path.isfile(txt_path) is False:
            return

        self.set_format(FORMAT_YOLO)
        t_yolo_parse_reader = YoloReader(txt_path, self.image)
        shapes = t_yolo_parse_reader.get_shapes()
        print(shapes)
        self.load_labels(shapes)
        self.canvas.verified = t_yolo_parse_reader.verified

    def load_create_ml_json_by_filename(self, json_path, file_path):
        if self.file_path is None:
            return
        if os.path.isfile(json_path) is False:
            return

        self.set_format(FORMAT_CREATEML)

        create_ml_parse_reader = CreateMLReader(json_path, file_path)
        shapes = create_ml_parse_reader.get_shapes()
        self.load_labels(shapes)
        self.canvas.verified = create_ml_parse_reader.verified

    def copy_previous_bounding_boxes(self):
        current_index = self.m_img_list.index(self.file_path)
        if current_index - 1 >= 0:
            prev_file_path = self.m_img_list[current_index - 1]
            self.show_bounding_box_from_annotation_file(prev_file_path)
            self.save_file()

    def toggle_paint_labels_option(self):
        for shape in self.canvas.shapes:
            shape.paint_label = self.display_label_option.isChecked()

    def toggle_draw_square(self):
        self.canvas.set_drawing_shape_to_square(self.draw_squares_option.isChecked())

    def file_watcher(self):
        if not self.default_save_dir or not self.dir_name:
            return
        # Time file save
        if len(self.speed_data) > 11:
            self.speed_data.pop(0)
        self.speed_data.append(time())
        data_count = len(self.speed_data)
        if data_count < 2:
            return
        delta_time_list = [self.speed_data[i+1]-self.speed_data[i] for i in range(data_count-1)]
        delta_data_count = len(delta_time_list)
        avg_time = sum(delta_time_list) / delta_data_count
        # Estimate time left
        label_file_num = len(os.listdir(self.default_save_dir))
        time_left = avg_time * (self.img_count - label_file_num)
        time_left = self.string_bundle.get_string('timeLeft') + \
                    str(int(time_left // 3600)) + "h" + \
                    str(int(time_left % 3600 // 60)) + "m" + \
                    str(int(time_left % 60)) + "s"
        # Draw speed curve
        self.speed_curve_plt.clear()
        self.speed_curve_plt.grid(True)
        self.speed_curve_plt.plot(delta_time_list)
        self.speed_curve_plt.plot(range(delta_data_count), [avg_time]*delta_data_count)
        self.speed_curve_plt.set_title(time_left)

    def label_watcher(self):
        label_dict = list_label(self.default_save_dir)
        self.label_stat_table.clear()
        self.label_stat_table.setHorizontalHeaderLabels(
            [self.string_bundle.get_string('tableHeaderLabel'), 
             self.string_bundle.get_string('tableHeaderCount')])
        self.label_stat_table.setRowCount(len(label_dict))
        for i, (label, count) in enumerate(label_dict.items()):
            label_item = QTableWidgetItem(label)
            count_item = QTableWidgetItem(str(count))
            self.label_stat_table.setItem(i, 0, label_item)
            self.label_stat_table.setItem(i, 1, count_item)

    def label_batch_export(self):
        dialog = QInputDialog()
        export_path, flag = dialog.getText(self,
            self.string_bundle.get_string('exportTo'), self.string_bundle.get_string('exportTo'),
            QLineEdit.EchoMode.Normal, self.default_save_dir, Qt.WindowFlags(), Qt.InputMethodHints())
        if not flag:
            return
        items = [self.label_stat_table.item(i, 0) for i in range(self.label_stat_table.rowCount())]
        items = set(i.text() for i in items)
        selected = self.label_stat_table.selectedItems()[::2]
        selected = set(i.text() for i in selected)
        del_labels = items - selected
        del_label(self.default_save_dir, export_path, *del_labels)
        # 显示状态
        self.statusBar().showMessage(self.string_bundle.get_string('exportSuccessfulTo') + f'{export_path}')
        self.statusBar().show()


    def label_batch_edit(self):
        selected = self.label_stat_table.selectedItems()
        dialog = QInputDialog()
        label_change_to, flag = dialog.getText(self,
            self.string_bundle.get_string('changeLabelTo'), self.string_bundle.get_string('changeLabelTo'),
            QLineEdit.EchoMode.Normal, selected[0].text(), Qt.WindowFlags(), Qt.InputMethodHints())
        if not flag:
            return
        for item in selected[::1]:
            label_from = item.text()
            change_label(self.default_save_dir, self.default_save_dir, label_from, label_change_to)
        # Fresh label static
        self.label_watcher()
        # 显示状态
        self.statusBar().showMessage(
            self.string_bundle.get_string('changeSuccessfulTo') + f'{label_change_to}')
        self.statusBar().show()

    def label_batch_delete(self):
        message_box = QMessageBox()
        message_box.setText(self.string_bundle.get_string('deleteCheck'))
        message_box.setStandardButtons(QMessageBox.StandardButton.Ok | QMessageBox.StandardButton.Cancel)
        message_box.setDefaultButton(QMessageBox.StandardButton.Cancel)
        flag = message_box.exec()
        if flag == QMessageBox.StandardButton.Cancel:
            # 显示状态
            self.statusBar().showMessage(self.string_bundle.get_string('deleteCancel'))
            self.statusBar().show()
            return
        selected = self.label_stat_table.selectedItems()[::2]
        del_labels = [i.text() for i in selected]
        del_label(self.default_save_dir, self.default_save_dir, *del_labels)
        # Fresh label static
        self.label_watcher()
        # 显示状态
        self.statusBar().showMessage(self.string_bundle.get_string('deleteSuccessful'))
        self.statusBar().show()


def inverted(color):
    return QColor(*[255 - v for v in color.getRgb()])


def read(filename, default=None):
    try:
        reader = QImageReader(filename)
        reader.setAutoTransform(True)
        return reader.read()
    except:
        return default


def get_main_app(argv=[]):
    """
    Standard boilerplate Qt application code.
    Do everything but app.exec_() -- so that we can test the application in one thread
    """
    app = QApplication(argv)
    app.setApplicationName(__appname__)
    app.setWindowIcon(new_icon("app"))
    # Tzutalin 201705+: Accept extra agruments to change predefined class file
    argparser = argparse.ArgumentParser()
    argparser.add_argument("image_dir", nargs="?")
    argparser.add_argument("class_file",
                           default=os.path.join(os.path.dirname(__file__), "data", "predefined_classes.txt"),
                           nargs="?")
    argparser.add_argument("save_dir", nargs="?")
    args = argparser.parse_args(argv[1:])

    args.image_dir = args.image_dir and os.path.normpath(args.image_dir)
    args.class_file = args.class_file and os.path.normpath(args.class_file)
    args.save_dir = args.save_dir and os.path.normpath(args.save_dir)

    # Usage : labelImg.py image classFile saveDir
    win = MainWindow(args.image_dir,
                     args.class_file,
                     args.save_dir)
    win.show()
    return app, win


def main():
    """construct main app and run it"""
    app, _win = get_main_app(sys.argv)
    return app.exec_()

if __name__ == '__main__':
    sys.exit(main())