# -*- coding: utf-8 -*-

# pylint: disable=invalid-name,no-name-in-module,too-many-lines,unused-argument

# -----------------------------------------------------------------------------
# Copyright (c) 2016-2017 Anaconda, Inc.
#
# May be copied and distributed freely only as part of an Anaconda or
# Miniconda installation.
# -----------------------------------------------------------------------------

"""Main Application Window."""

from __future__ import absolute_import, division

import contextlib
import os
import typing
from distutils.version import LooseVersion  # pylint: disable=deprecated-module
import psutil
from qtpy.QtCore import QPoint, QSize, Qt, QTimer, QUrl, Signal
from qtpy.QtGui import QDesktopServices
from qtpy.QtWidgets import QApplication, QHBoxLayout, QMainWindow, QVBoxLayout, QWidget
from anaconda_navigator import __version__, __file__ as NAVIGATOR_ROOT_FILE
from anaconda_navigator.api.anaconda_api import AnacondaAPI
from anaconda_navigator.config import CHANNELS_PATH, CONF, MAC, WIN, AnacondaBrand
from anaconda_navigator.static import images
from anaconda_navigator.utils import attribution
from anaconda_navigator.utils import constants as C
from anaconda_navigator.utils import anaconda_solvers
from anaconda_navigator.utils.analytics import GATracker
from anaconda_navigator.utils.launch import launch
from anaconda_navigator.utils.logs import logger
from anaconda_navigator.utils.misc import set_windows_appusermodelid
from anaconda_navigator.utils.qthelpers import create_action
from anaconda_navigator.utils.styles import BLUR_SIZE
from anaconda_navigator.utils import workers
from anaconda_navigator.widgets import ButtonBase, FrameBase, LabelBase, QSvgWidget, SpacerHorizontal
from anaconda_navigator.widgets.dialogs import MessageBoxError, MessageBoxQuestion
from anaconda_navigator.widgets.dialogs.about import AboutDialog
from anaconda_navigator.widgets.dialogs.channels import DialogChannels
from anaconda_navigator.widgets.dialogs.logger import LogViewerDialog
from anaconda_navigator.widgets.dialogs.login import TeamEditionAddChannelsPage
from anaconda_navigator.widgets.dialogs.offline import DialogOfflineMode
from anaconda_navigator.widgets.dialogs.preferences import PreferencesDialog
from anaconda_navigator.widgets.dialogs.quit import (
    ClosePackageManagerDialog, QuitApplicationDialog, QuitBusyDialog, QuitRunningAppsDialog,
)
from anaconda_navigator.widgets.dialogs.update import DialogUpdateApplication
from anaconda_navigator.widgets.tabs.community import CommunityTab
from anaconda_navigator.widgets.tabs.home import HomeTab
from anaconda_navigator.widgets.tabs.tabwidget import TabWidget
from . import account_components
from . import application_components
from . import common
from . import environment_components
from . import issue_solvers
from . import notification_components

if typing.TYPE_CHECKING:
    import typing_extensions

    class ComponentInitializer(typing_extensions.Protocol):  # pylint: disable=too-few-public-methods
        """Common interface for component initializers."""

        __alias__: str

        def __call__(self, parent: 'MainWindow') -> common.Component:
            """Initialize new :class:`~anaconda_navigator.main_window.common.Component` instance."""


# --- Widgets used with CSS styling
# -----------------------------------------------------------------------------

class ButtonHeaderUpdate(ButtonBase):
    """Button used in CSS styling."""


class FrameHeader(FrameBase):
    """
    Frame used in CSS styling.
    Top application header.
    """


class FrameBody(FrameBase):
    """Frame used in CSS styling."""


class LabelHeaderLogo(LabelBase):
    """Label used in CSS styling."""


class LabelHeaderUpdate(LabelBase):
    """Label used in CSS styling."""


class LabelBeta(LabelBase):
    """Label used in CSS styling."""


class LabelWarning(LabelBase):
    """Label used in CSS styling."""

    def set_offline_mode_text(self):  # pylint: disable=missing-function-docstring
        offline_text = '<i>Working in offline mode</i>'
        tooltip = DialogOfflineMode.MESSAGE_TOOL
        self.set_text(offline_text, tooltip)

    def set_text(self, text, tooltip=None):  # pylint: disable=missing-function-docstring
        self.setText(text)
        self.setToolTip(tooltip)

    def clear(self):  # pylint: disable=missing-function-docstring
        self.setText('')
        self.setToolTip('')


# --- Main widget
# -----------------------------------------------------------------------------


class MainWindowComponents(typing.Mapping[str, common.Component]):
    """
    Container for different components of the :class:`~MainWindow`.

    Created to split and group functionality of the MainWindow.
    """

    __slots__ = ('__parent', '__content')

    def __init__(self, parent: 'MainWindow') -> None:
        """Initialize new :class:`~MainWindowComponents` instance."""
        self.__parent: 'typing_extensions.Final[MainWindow]' = parent
        self.__content: 'typing_extensions.Final[typing.Dict[str, common.Component]]' = {}

    def push(self, component: 'ComponentInitializer') -> None:
        """Add new component to the pool."""
        key: typing.Optional[str] = getattr(component, '__alias__', None)
        if not key:
            raise ValueError('component must have a valid name')
        if key in self.__content:
            raise KeyError('component with same name is already added')
        self.__content[key] = component(parent=self.__parent)

    def for_each(self, action: typing.Callable[[common.Component], None]) -> None:
        """Apply single action to all environments."""
        component: common.Component
        for component in self.__content.values():
            action(component)

    def __getattr__(self, key: str) -> common.Component:
        """Retrieve single component as attribute."""
        try:
            return self.__content[key]
        except KeyError:
            raise AttributeError(f'{type(self).__name__} object has no attribute {key!r}') from None

    def __getitem__(self, key: str) -> common.Component:
        """Retrieve single component as item."""
        return self.__content[key]

    def __len__(self) -> int:
        """Retrieve total number of components in pool."""
        return len(self.__content)

    def __iter__(self) -> typing.Iterator[str]:
        """Iterate through component names in pool."""
        return iter(self.__content)

    # Common proxy-methods

    def setup(self, worker: typing.Any, output: typing.Any, error: str, initial: bool) -> None:
        """Perform component configuration from `conda_data`."""
        self.for_each(lambda component: component.setup(worker=worker, output=output, error=error, initial=initial))

    def update_style_sheet(self) -> None:
        """Update style sheet of the tab."""
        self.for_each(lambda component: component.update_style_sheet())

    def start_timers(self) -> None:
        """Start component timers."""
        self.for_each(lambda component: component.start_timers())

    def stop_timers(self) -> None:
        """Stop component timers."""
        self.for_each(lambda component: component.stop_timers())


class MainWindow(QMainWindow):  # pylint: disable=too-many-instance-attributes,too-many-public-methods
    """Main window widget."""

    sig_ready = Signal()
    sig_conda_ready = Signal()
    sig_setup_ready = Signal()
    sig_logged_in = Signal()
    sig_logged_out = Signal()

    DOCS_URL = 'https://docs.anaconda.com/anaconda/navigator'
    FEATURED_CHANNELS = ()  # ('anaconda-fusion', )

    def __init__(  # pylint: disable=too-many-arguments,too-many-branches,too-many-locals,too-many-statements
        self,
        splash=None,
        config=CONF,
        tab_home=True,
        tab_environments=True,
        tab_learning=True,
        tab_community=True,
    ):
        """Main window widget."""
        super().__init__()

        self.__components: 'typing_extensions.Final[MainWindowComponents]' = MainWindowComponents(parent=self)
        self.components.push(notification_components.NotificationsComponent)

        for _ in anaconda_solvers.POOL.solve():
            pass

        # Variables (Global)
        self.api = AnacondaAPI()
        self.initial_setup = True
        self.setup_ready = False
        self.tracker = None
        self.config = config
        self.maximized_flag = True
        self.first_run = self.config.get('main', 'first_run')
        self.application_update_version = None
        self.restart_required = None
        self._toolbar_setup_ready = False  # See issue 1142

        # Variables (Testing)
        self._dialog_about = None
        self._dialog_logs = None
        self._dialog_preferences = None
        self._dialog_update = None
        self._dialog_message_box = None
        self._dialog_quit = None
        self._dialog_quit_busy = None
        self._dialog_quit_running_apps = None
        self._dialog_offline = None

        self._dialog_channels = None
        self._dialog_environment_action = None

        # Configuration stability
        solved_error: issue_solvers.SolvedError
        issue_context: issue_solvers.ConfigurationContext = issue_solvers.ConfigurationContext(
            api=self.api,
            config=self.config,
        )
        for solved_error in issue_solvers.CONFIGURATION_POOL.solve(context=issue_context):
            self.components.notifications.information_message_box(
                text=solved_error.message,
                title=solved_error.caption,
            )

        # Variables (Conda handling)
        self.busy_conda: bool = False
        self.current_prefix: str = self.config.get('main', 'default_env')

        # Fix windows displaying the right icon
        # See https://github.com/ContinuumIO/navigator/issues/1340
        if WIN:
            res = set_windows_appusermodelid()
            logger.info('appusermodelid: %s', res)

        # Widgets (Refresh timers, milliseconds)
        self._timer_offline = QTimer()  # Check for connectivity
        self._timer_offline.setInterval(4713)

        self._timer_health_check: 'typing_extensions.Final[QTimer]' = QTimer()
        self._timer_health_check.setInterval(10000)

        # Widgets
        self.tab_home = None
        self.tab_learning = None
        self.tab_community = None
        self.splash = splash
        self.frame_header = FrameHeader(self)
        self.frame_body = FrameBody(self)
        self.label_logo = QSvgWidget(images.ANACONDA_NAVIGATOR_LOGO)
        self.label_warning = LabelWarning()
        self.button_update_available = ButtonHeaderUpdate('Upgrade Now')
        self.widget = QWidget()
        self.stack = TabWidget(self)

        # Widgets setup
        self.setWindowTitle('Anaconda Navigator')
        self.button_update_available.setVisible(False)
        self.label_logo.setFixedSize(QSize(395, 50))

        # Load custom API URL on batch installs and set it
        self.set_initial_batch_config()

        attribution.UPDATER.instance.sig_updated.connect(self.stack.add_advertisement)
        self.stack.add_advertisement()
        self.stack.add_link(
            'Documentation',
            url=self.DOCS_URL,
            utm_medium='nav-docs',
        )
        self.stack.add_link(
            'Anaconda Blog',
            url='https://www.anaconda.com/blog',
            utm_medium='nav-blog',
        )
        self.stack.add_social('Twitter', url='https://twitter.com/AnacondaInc')
        self.stack.add_social('Youtube', url='https://www.youtube.com/c/continuumio')
        self.stack.add_social('Github', url='https://github.com/ContinuumIO')

        self.components.push(account_components.AccountsComponent)
        self.components.push(application_components.ApplicationsComponent)

        if tab_home:
            self.tab_home = HomeTab(parent=self)
            self.stack.addTab(self.tab_home, text='Home')

            # Signals
            self.tab_home.sig_item_selected.connect(self.select_environment)
            self.tab_home.sig_channels_requested.connect(self.show_channels)
            self.tab_home.sig_url_clicked.connect(self.open_url)
            self.tab_home.sig_launch_action_requested.connect(self.components.applications.launch_application)
            self.tab_home.sig_conda_action_requested.connect(self.components.applications.conda_application_action)

        if tab_environments:
            self.components.push(environment_components.EnvironmentsComponent)

        if tab_learning:
            self.tab_learning = CommunityTab(
                parent=self,
                tags=['webinar', 'documentation', 'video', 'training'],
                utm_medium='learning'
            )
            self.stack.addTab(self.tab_learning, text='Learning')

        if tab_community:
            self.tab_community = CommunityTab(
                parent=self,
                tags=['event', 'forum', 'social'],
                utm_medium='community'
            )
            self.stack.addTab(self.tab_community, text='Community')

        self.all_tab_widgets = [
            self.tab_home,
            self.tab_community,
            self.tab_learning,
        ]

        # Layout
        layout_header = QHBoxLayout()
        layout_header.addWidget(self.label_logo)
        layout_header.addStretch()
        layout_header.addWidget(self.label_warning)
        layout_header.addWidget(SpacerHorizontal())
        layout_header.addWidget(self.button_update_available)
        layout_header.addWidget(SpacerHorizontal())
        layout_header.addWidget(self.components.accounts.account_label_widget)
        layout_header.addWidget(SpacerHorizontal())
        layout_header.addWidget(self.components.accounts.login_button)
        self.frame_header.setLayout(layout_header)

        layout_body = QHBoxLayout()
        layout_body.addWidget(self.stack)
        layout_body.setContentsMargins(0, 0, 0, 0)
        layout_body.setSpacing(0)
        self.frame_body.setLayout(layout_body)

        layout_main = QVBoxLayout()
        layout_main.addWidget(self.frame_header)
        layout_main.addWidget(self.frame_body)
        layout_main.setContentsMargins(0, 0, 0, 0)
        layout_main.setSpacing(0)
        self.widget.setLayout(layout_main)
        self.setContentsMargins(0, 0, 0, 0)
        self.setCentralWidget(self.widget)

        # Signals
        self._timer_offline.timeout.connect(self.check_internet_connectivity)
        self._timer_health_check.timeout.connect(self.api.health_check)
        self.api.sig_api_health.connect(self.show_api_health_label)
        self.button_update_available.clicked.connect(self.update_application)
        self.stack.sig_current_changed.connect(self._track_tab)
        self.stack.sig_current_changed.connect(self.fix_tab_order)
        self.stack.sig_url_clicked.connect(self.open_url)
        self.sig_setup_ready.connect(self.check_package_cache)
        self.sig_setup_ready.connect(self.check_internet_connectivity)

        # Setup
        self.config.set('main', 'last_status_is_offline', None)
        self.api.set_data_directory(CHANNELS_PATH)
        self.update_style_sheet()
        self.setMinimumWidth(1200)

        # Add featured_channels
        worker = self.api.conda_config(prefix=self.current_prefix)
        worker.sig_chain_finished.connect(self.add_featured_channels)

        worker_data = self.api.conda_data(prefix=self.current_prefix)
        worker_data.sig_chain_finished.connect(self.setup)

        attribution.UPDATER.instance.update.worker().start()  # pylint: disable=no-member

    @property
    def components(self) -> MainWindowComponents:  # noqa: D401
        """Components of the :class:`~MainWindow`."""
        return self.__components

    # Helpers
    # -------------------------------------------------------------------------
    def _track_tab(self, index=None):
        """Track the active tab by index, or set `Home` when index is None."""
        if index is None:
            index = self.stack.currentIndex()

        text = self.stack.currentText()
        if text:
            text = text.lower()

        if self.tracker and text:
            page = f'/{text}'
            self.tracker.track_page(page)

    # --- Public API
    # -------------------------------------------------------------------------
    def set_initial_batch_config(self):
        """
        Set configuration settings that force conda and client config update.
        """
        def is_valid_api(url, verify):
            """Check if a given URL is a valid anaconda api endpoint."""
            output = self.api.download_is_valid_api_url(
                url,
                non_blocking=False,
                verify=verify,
            )
            return output

        verify = True

        # SSL certificate
        default_ssl_certificate = self.config.get('main', 'default_ssl_certificate')
        if default_ssl_certificate is not None:
            # Check if it is a valid path, and check if it is boolean
            if isinstance(default_ssl_certificate, bool) or os.path.isfile(default_ssl_certificate):
                self.api.client_set_ssl(default_ssl_certificate)
                # self.config.set('main', 'default_ssl_certificate', None)
                verify = default_ssl_certificate

        # API URL
        default_anaconda_api_url = self.config.get('main', 'default_anaconda_api_url')
        if default_anaconda_api_url is not None:
            if is_valid_api(default_anaconda_api_url, verify=verify):
                self.api.client_set_api_url(default_anaconda_api_url)
                # self.config.set('main', 'default_anaconda_api_url', None)

    def setup(self, worker, output, error):
        """
        Perform initial setup and configuration.

        This is the first method called after the main window has been created.
        """
        solved_error: issue_solvers.SolvedError
        solved_tags: typing.Set[str] = set()
        issue_context: issue_solvers.ConflictContext = issue_solvers.ConflictContext(
            api=self.api,
            config=self.config,
            conda_info=output,
        )
        for solved_error in issue_solvers.CONFLICT_POOL.solve(context=issue_context):
            self.components.notifications.information_message_box(
                text=solved_error.message,
                title=solved_error.caption,
            )
            solved_tags.update(solved_error.tags)
        if 'default_env' in solved_tags:
            self.select_environment(prefix=self.config.get('main', 'default_env'))
            return

        self.check_internet_connectivity()

        if self.initial_setup:
            logger.info('Initial setup')

            # Get user info if it has previously logged in via anaconda client
            self.set_splash('Loading user...')

            user = self.components.accounts.detect_new_login()
            self.components.accounts.update_login_status(user)
            self.set_splash('Preparing interface...')
            self.setup_toolbars()

            self.set_splash('Loading bundled metadata...')
            self.api.load_bundled_metadata()

            self.post_setup(conda_data=output)

        else:
            logger.info('Normal setup')

            # Reset home and environment tab
            if self.tab_home:
                self.tab_home.setup(output)

            # Check for updates
            packages = output['packages']
            info = output.get('processed_info', {})
            is_root_writable = info.get('root_writable', False)
            self.check_for_updates(packages=packages, is_root_writable=is_root_writable)

            self.fix_tab_order()

        self.components.setup(worker=worker, output=output, error=error, initial=self.initial_setup)
        self.initial_setup = False

    def post_setup(self, conda_data):
        """Setup tab widgets."""
        self.setup_ready = True
        self.config.set('main', 'first_run', False)

        if self.tab_home:
            self.set_busy_status(conda=True)
            self.set_splash('Loading applications...')
            self.tab_home.setup(conda_data)
        if 'environments' in self.components:
            self.set_busy_status(conda=True)
            self.set_splash('Loading environments...')
            self.components.environments.tab.setup(conda_data)
        if self.tab_community:
            self.set_splash('Loading content...')
            self.tab_community.setup()
        if self.tab_learning:
            self.set_splash('Loading content...')
            self.tab_learning.setup()
        self.update_style_sheet()

        geo = self.config.get('main', 'geo', None)
        if geo:
            # In case Navigator is installed in an env that has a different
            # python version than root (root == py3, env == py2 or viceversa)
            try:
                self.restoreGeometry(geo)
                self.show()
            except BaseException:  # pylint: disable=broad-except
                self.showMaximized()
        else:
            self.showMaximized()
        self.post_visible_setup(conda_data)

    def setup_toolbars(self):
        """Setup toolbar menus and actions."""
        # See issue #1142
        if self._toolbar_setup_ready:
            return

        menubar = self.menuBar()

        file_menu = menubar.addMenu('&File')
        file_menu.addAction(create_action(self, '&Preferences', triggered=self.show_preferences, shortcut='Ctrl+P'))
        file_menu.addAction(create_action(self, '&Restart', triggered=self.restart, shortcut='Ctrl+R'))
        file_menu.addAction(create_action(self, '&Quit', triggered=self.close, shortcut='Ctrl+Q'))

        helpmenu = menubar.addMenu('&Help')
        helpmenu.addAction(create_action(self, '&Online Documentation', triggered=lambda: self.open_url(self.DOCS_URL)))
        helpmenu.addAction(create_action(self, '&Logs viewer', triggered=self.show_log_viewer, shortcut='F6'))
        helpmenu.addSeparator()
        helpmenu.addAction(create_action(self, '&About', triggered=self.show_about))
        self._toolbar_setup_ready = True

    def post_visible_setup(self, conda_data):
        """Setup after show method has been applied."""
        if self.splash:
            self.splash.hide()

        self.config.set('main', 'first_run', False)

        # Start the tracker only after post_visible_setup
        self.tracker = GATracker()
        self._track_tab(0)  # Start tracking home

        packages = conda_data.get('packages')
        info = conda_data.get('processed_info', {})
        is_root_writable = info.get('root_writable', False)
        self.check_for_updates(packages=packages, is_root_writable=is_root_writable)

        # Fix tab order
        self.fix_tab_order()
        buttons = self.stack.tabbar.buttons
        if buttons:
            buttons[0].setFocus()

        worker = self.api.conda_config_and_sources(prefix=self.current_prefix)
        worker.sig_chain_finished.connect(self.check_outdated_channels)

        self.check_internet_connectivity()
        self.sig_setup_ready.emit()

    def set_widgets_enabled(self, value):
        """Set the widgets enabled/disabled status for subwidgets and tabs."""
        if self.tab_home:
            self.tab_home.set_widgets_enabled(value)
        if 'environments' in self.components:
            self.components.environments.tab.set_widgets_enabled(value)

    def update_style_sheet(self):
        """Update custom CSS style sheet."""
        for tab in self.all_tab_widgets:
            if tab:
                tab.update_style_sheet()
        self.components.update_style_sheet()

    # --- Update Navigator
    # -------------------------------------------------------------------------
    def check_for_updates(self, packages=None, version=None, is_root_writable=False):
        """Check for application updates."""
        # Check if there is an update for navigator!
        navi_version = version or __version__

        self.button_update_available.setEnabled(False)
        self.button_update_available.setVisible(False)

        if packages:
            package_data = packages.get('anaconda-navigator')
            if package_data:
                versions = package_data.get('versions')
                if versions and (
                    LooseVersion(versions[-1]) > LooseVersion(navi_version)
                    or 'dev' in navi_version and versions[-1] == navi_version.replace('dev', '')
                ):
                    self.application_update_version = versions[-1]
                    self.button_update_available.setEnabled(True)
                    self.button_update_available.setVisible(True)
                    if not self.config.get('main', 'hide_update_dialog'):
                        self.update_application(
                            center_dialog=True,
                            is_root_writable=is_root_writable,
                        )

    def update_application(self, center_dialog=False, is_root_writable=False):
        """Update application to latest available version."""
        version = self.application_update_version
        qa_testing = version == '1000.0.0'

        if version:
            dlg = DialogUpdateApplication(
                version=version,
                startup=center_dialog,
                qa_testing=qa_testing,
                is_root_writable=is_root_writable,
            )
            # Only display one dialog at a time
            if self._dialog_update is None:

                self._dialog_update = dlg
                if not center_dialog:
                    height = self.button_update_available.height()
                    width = self.button_update_available.width()
                    point = self.button_update_available.mapToGlobal(QPoint(-dlg.WIDTH + width, height))
                    dlg.move(point)

                if self.tracker:
                    self.tracker.track_page('/update', pagetitle='Update Application Dialog')

                if dlg.exec_():
                    self.tracker.track_event('application', 'updated', version)
                    # Returns a pid or None if failed
                    pid = self.open_updater(version, is_root_writable=is_root_writable)
                    if pid is not None:
                        self.close()

            self._dialog_update = None
            self._track_tab()

    def open_updater(self, version, is_root_writable=False):
        """Open the Anaconda Navigator Updater"""
        self.tracker.track_event('application', 'updater-requested', version)
        leave_path_alone = True
        root_prefix = self.api.ROOT_PREFIX
        prefix = os.environ.get('CONDA_PREFIX', root_prefix)
        command = f'navigator-updater --latest-version {version} --prefix {prefix}'

        as_admin = WIN and not is_root_writable

        return launch(
            root_prefix=root_prefix,
            prefix=prefix,
            command=command,
            package_name='anaconda-navigator-updater',
            leave_path_alone=leave_path_alone,
            non_conda=True,
            as_admin=as_admin,
        )

    # --- Url handling
    # -------------------------------------------------------------------------
    # NOTE: Route ALL url handling to this method? or Make a global func?
    def open_url(self, url, category=None, action=None):
        """Open url and track event."""
        # print(url, category, action)
        qurl = QUrl(url)
        QDesktopServices.openUrl(qurl)
        self.tracker.track_event('help', 'documentation', url)

    # --- Client (Login)
    # -------------------------------------------------------------------------
    @property
    def conda_url(self):
        """Return the conda url based on the api info from config url."""
        api_info = self.api.download_get_api_info()
        url = api_info.get('conda_url', 'https://conda.anaconda.org')
        url = url[:-1] if url[-1] == '/' else url
        return url

    @property
    def api_url(self) -> str:
        """Return the api url from anaconda client config."""
        return self.api.client_get_api_url()

    # --- Dialogs
    # -------------------------------------------------------------------------
    def show_preferences(self):
        """Display the preferences dialog and apply the needed actions."""
        self.tracker.track_event('preferences', 'open')
        self.tracker.track_page('/preferences', pagetitle='Preferences dialog')
        self._dialog_preferences = PreferencesDialog(
            parent=self,
            config=self.config,
            environments=self.components.environments.environments,
        )

        # If the api url was changed by the user, a logout is triggered
        self._dialog_preferences.sig_urls_updated.connect(
            lambda au, cu: self.components.accounts.log_out_from_repository(),
        )
        self._dialog_preferences.exec_()
        self._dialog_preferences = None
        self._track_tab()

    def show_about(self):
        """Display the `About` dialog with information on the project."""
        self._dialog_about = AboutDialog(self)
        if self.tracker:
            self.tracker.track_page('/about', pagetitle='About dialog')
        self._dialog_about.sig_url_clicked.connect(self.open_url)
        self._dialog_about.exec_()
        self._dialog_about = None
        self._track_tab()

    def show_log_viewer(self):
        """Display the logs viewer to the user."""
        self._dialog_logs = LogViewerDialog()
        if self.tracker:
            self.tracker.track_page('/logs', pagetitle='Log Viewer Dialog')
        self._dialog_logs.exec_()
        self._dialog_logs = None
        self._track_tab()

    def show_error_message(self, error_name, error_text):
        """Display application error message."""
        self.set_busy_status(conda=True)
        if 'UnsatisfiableSpecifications' in error_name:
            report = False
        else:
            report = True

        if report:
            title = 'Conda process error'
            text = 'The following errors occurred:'
            error_msg = error_text
        else:
            title = 'Unsatisfiable package specifications:'
            text = 'The following specifications were found to be in conflict:'
            package_errors = [e.strip() for e in error_text.split('\n') if '-' in e]
            error_msg = '\n'.join(package_errors)
            error_msg += '\n\n\nA package you tried to install conflicts with another.'

        # Check if offline mode and provide a custom message
        if self.api.is_offline():
            report = False
            if 'PackagesNotFoundError' in error_name:
                title = 'Package not available in offline mode'
                error_msg = (
                    'Some of the functionality of Anaconda Navigator will be '  # pylint: disable=implicit-str-concat
                    'limited in <b>offline mode</b>.<br><br>Installation and upgrade of packages will be subject to '
                    'the packages currently available on your package cache.'
                )

        if self.tracker:
            self.tracker.track_page('/messagebox/error', pagetitle='Conda error message box')
        dlg = MessageBoxError(
            text=text,
            error=error_msg,
            title=title,
            report=False,  # Disable reporting on github
            learn_more='http://conda.pydata.org/docs/'
            'troubleshooting.html#unsatisfiable'
        )
        self._dialog_message_box = dlg
        dlg.setMinimumWidth(400)
        dlg.exec_()
        self.set_busy_status(conda=False)
        self.update_status()
        self._track_tab()

    def show_offline_mode_dialog(self):
        """Show offline mode dialog"""
        if self._dialog_offline is not None:
            # Dialog currently open
            return

        show_dialog = not self.config.get('main', 'hide_offline_dialog')
        first_time_offline = self.config.get('main', 'first_time_offline')

        if show_dialog or first_time_offline:
            self._dialog_offline = DialogOfflineMode(parent=self)
            if self.tracker:
                self.tracker.track_page('/offline', pagetitle='Offline dialog')

            if self._dialog_offline.exec_():
                pass

            self.config.set('main', 'first_time_offline', False)
            self._dialog_offline = None
            self._track_tab()

    # --- Conda (Dialogs)
    # -------------------------------------------------------------------------
    def add_default_channels(self, conda_data):
        """Add defaults to user condarc if it does not exist."""
        config_sources = conda_data.get('config_sources', {})
        user_rc = self.api._conda_api.user_rc_path  # pylint: disable=protected-access
        user_config = config_sources.get(user_rc, {})
        user_channels = user_config.get('channels', [])
        if len(user_channels) == 0 or not os.path.isfile(user_rc):
            worker = self.api.conda_config_add('channels', 'defaults')
            worker.communicate()
        self.api.client_get_ssl()

    def check_outdated_channels(self, worker, conda_data, error):
        """Check if the user has binstar channels as part of the config."""
        self.set_busy_status(conda=True)
        config = conda_data.get('config', {})
        current_channels = config.get('channels', [])
        self.add_default_channels(conda_data)
        outdated_channels = []
        if 'anaconda.org' in self.api_url:  # pylint: disable=unsupported-membership-test
            for channel in current_channels:
                if 'binstar.org' in channel:
                    outdated_channels.append(channel)

        if outdated_channels:
            chs = [f'- <b>{ch}</b><br>' for ch in outdated_channels]
            chs = ''.join(chs)
            text = (
                f'We detected some outdated channels making use of <b>binstar.org</b><br><br>'
                f'{chs}<br><br>'
                f'Do you want to update them?'
            )

            self.tracker.track_page(
                '/channels/outdated',
                pagetitle='Show outdated channels check dialog',
            )
            self._dialog_message_box = MessageBoxQuestion(text=text, title='Outdated channels detected')
            self._dialog_message_box.setMinimumWidth(300)

            if self._dialog_message_box.exec_():
                for channel in outdated_channels:
                    new_channel = channel.replace('binstar.org', 'anaconda.org')
                    worker = self.api.conda_config_add('channels', new_channel)
                    worker.communicate()
                    worker = self.api.conda_config_remove('channels', channel)
                    worker.communicate()
            self._dialog_message_box = None
            self._track_tab()
        self.set_busy_status(conda=False)

    def show_channels(self, button=None, sender=None):
        """Show the conda channels configuration dialog."""
        brand = self.api.config.get('main', 'logged_brand')
        if brand == AnacondaBrand.TEAM_EDITION:
            if TeamEditionAddChannelsPage(btn_cancel_msg='Cancel').exec_():
                self.update_index(self)
            self._track_tab()
            return

        def _accept_channels_dialog(button):
            button.setEnabled(True)
            button.setFocus()
            button.toggle()
            self._dialog_channels = None  # for testing

        if sender == C.TAB_HOME:
            pass
        elif sender == C.TAB_ENVIRONMENT:
            pass

        self.tracker.track_page('/channels', pagetitle='Show channels dialog')
        dlg = DialogChannels(parent=self)
        self._dialog_channels = dlg  # For testing
        dlg.update_style_sheet()
        worker = self.api.conda_config_sources(prefix=self.current_prefix)
        worker.sig_chain_finished.connect(dlg.setup)
        dlg.sig_channels_updated.connect(self.update_channels)

        if button:
            button.setDisabled(True)
            dlg.rejected.connect(lambda: button.setEnabled(True))
            dlg.rejected.connect(button.toggle)
            dlg.rejected.connect(button.setFocus)
            dlg.accepted.connect(lambda v=None: _accept_channels_dialog(button))

            geo_tl = button.geometry().topLeft()
            tl = button.parentWidget().mapToGlobal(geo_tl)
            x = tl.x() - BLUR_SIZE
            y = tl.y() + button.height() - BLUR_SIZE

            # Ensure channels dialog stays visible
            # See https://github.com/ContinuumIO/navigator/issues/1254
            x_right_dialog = x + dlg.WIDTH
            x_right_screen = QApplication.desktop().availableGeometry().width()
            if x_right_dialog > x_right_screen:
                x = x - (x_right_dialog - x_right_screen)
            elif x < 0:
                x = 0

            dlg.move(x, y)

        if dlg.exec_():
            pass

        dlg.button_add.setFocus()
        self._track_tab()

    def show_cancel_process(self):
        """Allow user to cancel an ongoing process."""
        if self.is_busy():
            dlg = ClosePackageManagerDialog(parent=self)
            self._dialog_quit_busy = dlg

            if self._dialog_quit_busy.exec_():
                self.update_status(action='Process cancelled', message=None)
                self.api.conda_terminate()
                self.api.download_terminate()
                self.api.conda_clear_lock()

            self.current_prefix = self.api.ROOT_PREFIX
            self.set_busy_status(conda=False)
            self.select_environment(prefix=self.api.ROOT_PREFIX)

    # --- Conda
    # -------------------------------------------------------------------------

    def select_environment(self, name=None, prefix=None, sender=None):
        """Select the active conda environment of the application."""
        self.set_busy_status(conda=True)
        self.current_prefix = prefix
        if 'environments' in self.components:
            self.components.environments.tab.set_loading(prefix=prefix, value=True)
        msg = f'Loading packages of <b>{prefix}</b>...'
        self.update_status(action=msg, value=0, max_value=0)
        self.set_widgets_enabled(False)
        worker = self.api.conda_data(prefix=self.current_prefix)
        worker.sig_chain_finished.connect(self.setup)

    def check_package_cache(self) -> None:
        """Check if package cache is obsolete and should be updated."""
        # pylint: disable=protected-access,unpacking-non-sequence

        repodata, cache_updated = self.api._conda_api.get_repodata(append_mtime=True)

        navigator_ctime: float = os.path.getctime(NAVIGATOR_ROOT_FILE)  # date of fresh installation
        navigator_mtime: float = os.path.getmtime(NAVIGATOR_ROOT_FILE)  # date of last update (might be before ctime)

        if (not repodata) or (cache_updated < max(navigator_ctime, navigator_mtime)):
            self.update_index(self)

    def update_index(self, sender):
        """Update conda repodata index."""
        self.set_busy_status(conda=True)
        self.update_status('Updating package index and metadata...', '', value=0, max_value=0)
        worker = self.api.update_index_and_metadata(prefix=self.current_prefix)
        worker.sig_chain_finished.connect(self._conda_output_ready)

    def update_channels(self, sources_added, sources_removed):
        """Save updated channels to the conda config."""
        self.update_status(
            action='Updating channel configuration...',
            value=0,
            max_value=0,
        )

        for (source, channel) in sources_added:
            worker = self.api.conda_config_add('channels', channel, file=source)
            worker.communicate()
        for (source, channel) in sources_removed:
            worker = self.api.conda_config_remove('channels', channel, file=source)
            worker.communicate()

        worker = self.api.update_index_and_metadata(prefix=self.current_prefix)
        worker.sig_chain_finished.connect(self._conda_output_ready)

    def add_featured_channels(self, worker, conda_config, error):
        """Automatically add featured channels on startup if not found."""
        self.set_splash('Adding featured channels...')
        add_channels = self.config.get('main', 'add_default_channels')
        current_channels = conda_config.get('channels', [])
        if 'anaconda.org' in self.api_url and add_channels:
            for ch in self.FEATURED_CHANNELS:
                if ch not in current_channels:
                    worker = self.api.conda_config_add('channels', ch)
                    worker.communicate()
            self.config.set('main', 'add_default_channels', False)

    def _conda_partial_output_ready(self, worker, output, error):
        """Callback."""
        self.set_busy_status(conda=True)

        action_msg = worker.action_msg

        # Get errors and data from output if it exists
        if not isinstance(output, dict):
            output = {}

        # name = output.get('name')  # Linking step gone?
        fetch = output.get('fetch')  # Fetching step
        value = output.get('progress', 0)
        max_value = output.get('maxval', 0)

        if fetch:
            message = f'Fetching <b>{fetch}</b>...'
            self.update_status(
                action=action_msg,
                message=message,
                value=int(value * 100),
                max_value=int(max_value * 100),
            )

    def _conda_output_ready(self, worker, output, error):
        """Callback for handling action finished."""
        self.set_busy_status(conda=False)

        action = worker.action
        if not isinstance(output, dict):
            output = {}

        error_text = output.get('error', '')
        exception_type = output.get('exception_type', '')
        exception_name = output.get('exception_name', '')
        # import from yaml provides empty dic, hence the True
        success = output.get('success', True)

        # Check if environment was created. Conda env does not have --json output, so we check if folder was created
        if action == C.ACTION_IMPORT:
            success = os.path.isdir(worker.prefix)

        is_error = error_text or exception_type or exception_name

        # Set the current prefix to the prefix stablihsed by worker
        old_prefix = getattr(worker, 'old_prefix', None)
        prefix = getattr(worker, 'prefix', old_prefix)

        # Set as current environment only if a valid environment
        if prefix and self.api.conda_environment_exists(prefix=prefix):
            self.current_prefix = prefix
        elif old_prefix and self.api.conda_environment_exists(prefix=old_prefix):
            # If there is an error when installing an application in a new
            # environment due to conflicts, restore the previous prefix
            self.current_prefix = old_prefix
        else:
            self.current_prefix = self.api.ROOT_PREFIX

        if is_error or error or not success:
            logger.error(error_text)
            self.show_error_message(exception_name, error_text)
            self.select_environment(prefix=self.current_prefix)
        else:
            if action == C.ACTION_REMOVE_ENV:
                self.select_environment(prefix=self.api.ROOT_PREFIX)
            else:
                self.select_environment(prefix=self.current_prefix)

    def check_internet_connectivity(self):
        """Check if there is internet available."""
        last_status_is_offline = self.config.get('main', 'last_status_is_offline')
        is_offline = self.api.is_offline()

        if is_offline != last_status_is_offline and self.setup_ready:
            self.config.set('main', 'last_status_is_offline', is_offline)

            if is_offline:
                # Disable login/logout button
                self.components.accounts.login_button.setDisabled(True)

                # Include label to indicate mode
                self.label_warning.set_offline_mode_text()
                self.show_offline_mode_dialog()
            else:
                # Restore buttons and text
                self.components.accounts.login_button.setEnabled(True)
                self.label_warning.clear()

    def show_api_health_label(self, healthy: bool) -> None:
        """Show error icon if TE api is not available"""
        if not healthy:
            self.tab_home.te_alert.show_error()
            self.components.environments.tab.widget.te_alert.show_error()
            self.components.accounts.show_error_icon(
                tooltip='Some things in the Home and Environments tabs may not work because '
                        'Anaconda Server can’t be reached. We will attempt to reconnect you periodically.'
            )
            return

        self.components.accounts.hide_error_icon()

        if self.config.get_logged_data()[0] == AnacondaBrand.TEAM_EDITION:
            self.tab_home.te_alert.show_info()
            self.components.environments.tab.widget.te_alert.show_info()
        else:
            self.tab_home.te_alert.hide_all()
            self.components.environments.tab.widget.te_alert.hide_all()

    def stop_timers(self):
        """Stop all refreshing timers."""
        self._timer_offline.stop()
        self.components.stop_timers()

    def start_timers(self):
        """Start all refreshing timers."""
        self._timer_offline.start()
        self._timer_health_check.start()
        self.components.start_timers()

    def fix_tab_order(self):
        """Fix tab order of UI widgets."""
        current_widget = self.stack.currentWidget()
        if current_widget is not None:
            ordered_widgets = [
                self.button_update_available,
                self.components.accounts.login_button,
            ]
            ordered_widgets += self.stack.tabbar.buttons
            next_widdget = self.stack.tabbar.links[0]
            ordered_widgets += current_widget.ordered_widgets(next_widdget)
            ordered_widgets += self.stack.tabbar.links
            ordered_widgets += self.stack.tabbar.links_social
            ordered_widgets += [self.button_update_available]

            for index in range(len(ordered_widgets) - 1):
                self.setTabOrder(ordered_widgets[index], ordered_widgets[index + 1])

    def restart(self):
        """Restart application."""
        root_prefix = self.api.ROOT_PREFIX
        prefix = os.environ.get('CONDA_PREFIX', root_prefix)
        leave_path_alone = True
        command = 'anaconda-navigator'
        self.restart_required = False
        if self.closing():
            launch(
                root_prefix=root_prefix,
                prefix=prefix,
                command=command,
                package_name='anaconda-navigator-restart',
                leave_path_alone=leave_path_alone,
            )
            self.restart_required = True
            self.close()

    def set_splash(self, message):
        """Set splash dialog message."""
        if self.splash:
            self.splash.show_message(message)
        QApplication.processEvents()

    def toggle_fullscreen(self):
        """Toggle fullscreen status."""
        if self.isFullScreen():
            if self.maximized_flag:
                self.showMaximized()
            else:
                self.showNormal()
        else:
            self.maximized_flag = self.isMaximized()
            self.showFullScreen()

    def set_busy_status(self, conda=None):
        """
        Update the busy status of conda and the application.

        Conda status is defined by actions taken on Home/Environments tab.

        The value will only update if True or False, if None, the current value
        set will remain.
        """
        if conda is not None and isinstance(conda, bool):
            self.busy_conda = conda
            if self.busy_conda:
                self.stop_timers()
            else:
                self.start_timers()

        if not self.busy_conda:
            self.sig_conda_ready.emit()

        if not any([self.busy_conda]):
            self.sig_ready.emit()

    def is_busy(self):
        """Return if the application is currently busy."""
        return self.busy_conda

    def update_status(self, action=None, message=None, value=None, max_value=None):
        """Update status bar."""
        if self.tab_home:
            self.tab_home.update_status(action=action, message=message, value=value, max_value=max_value)
        if 'environments' in self.components:
            self.components.environments.tab.update_status(
                action=action,
                message=message,
                value=value,
                max_value=max_value,
            )

    def closing(self):  # pylint: disable=too-many-branches
        """Closing helper method to reuse on close event and restart."""
        close = True
        if (not self.is_busy()) and (not self.config.get('main', 'hide_running_apps_dialog')):
            self.components.applications.update_running_processes()
            running_processes = self.components.applications.running_processes
            if running_processes:
                self.tracker.track_page('/quit/running', pagetitle='Quit running applications dialog')
                dialog = QuitRunningAppsDialog(parent=self, running_processes=running_processes)
                if dialog.exec_():
                    close_apps = self.config.get('main', 'running_apps_to_close')
                    for running_process in running_processes:
                        if running_process.package not in close_apps:
                            continue

                        process = psutil.Process(running_process.pid)
                        for child in process.children(recursive=True):
                            with contextlib.suppress(BaseException):
                                child.kill()

                        with contextlib.suppress(BaseException):
                            process.kill()
                else:
                    close = False
                self._track_tab()

        if close:
            if self.is_busy():
                if self.tracker:
                    self.tracker.track_page('/quit/busy', pagetitle='Quit busy dialog')
                self._dialog_quit_busy = QuitBusyDialog(parent=self)
                if not self._dialog_quit_busy.exec_():
                    close = False
                self._dialog_quit_busy = None
                self._track_tab()
            else:
                show_dialog = not self.config.get('main', 'hide_quit_dialog')
                if show_dialog:
                    if self.tracker:
                        self.tracker.track_page('/quit', pagetitle='Quit dialog')
                    self._dialog_quit = QuitApplicationDialog(parent=self)
                    if not self._dialog_quit.exec_():
                        close = False
                        self._track_tab()
                    self._dialog_quit = None

        return close

    # --- Qt methods
    # -------------------------------------------------------------------------
    def closeEvent(self, event):
        """Catch close event."""
        # If a restart was required don't ask self.closing again
        if (not self.restart_required) and (not self.closing()):
            event.ignore()
            return

        try:
            self.config.set('main', 'geo', bytes(self.saveGeometry()))
        except Exception as e:  # pylint: disable=broad-except
            logger.error(e)

        # hide main window showing that all primary activity is done
        self.hide()

        # wait for background tasks to finish
        workers.MANAGER.instance.cancel_all()
        workers.THREAD_POOL.reset()

    def keyPressEvent(self, event):
        """Override Qt method."""
        key = event.key()
        modifiers = event.modifiers()
        if key == Qt.Key_F5:
            self.update_style_sheet()
        elif key == Qt.Key_F11 and not MAC:
            self.toggle_fullscreen()
        elif key == Qt.Key_F and modifiers & Qt.ControlModifier and MAC:
            self.toggle_fullscreen()

        super().keyPressEvent(event)
