# This file is part of Gajim.
#
# Gajim is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published
# by the Free Software Foundation; version 3 only.
#
# Gajim is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with Gajim. If not, see <http://www.gnu.org/licenses/>.

from __future__ import annotations

from typing import Any
from typing import Literal
from typing import overload

import logging

from gi.repository import Gtk
from nbxmpp.errors import StanzaError
from nbxmpp.task import Task

from gajim.common import app
from gajim.common import ged
from gajim.common.events import AccountConnected
from gajim.common.events import AccountDisconnected
from gajim.common.helpers import event_filter
from gajim.common.helpers import to_user_string
from gajim.common.i18n import _

from gajim.gtk.assistant import Assistant
from gajim.gtk.assistant import ErrorPage
from gajim.gtk.assistant import Page
from gajim.gtk.assistant import SuccessPage

log = logging.getLogger('gajim.gtk.remove_account')


class RemoveAccount(Assistant):
    def __init__(self, account: str) -> None:
        Assistant.__init__(self)

        self.account = account

        try:
            self._client = app.get_client(account)
        except KeyError:
            self._client = None

        self._destroyed = False
        self._account_removed = False

        self.add_button('remove', _('Remove'), 'destructive-action')
        self.add_button('close', _('Close'))
        self.add_button('back', _('Back'))

        self.add_pages({'remove_choice': RemoveChoice(account),
                        'error': Error(),
                        'success': Success()})

        progress = self.add_default_page('progress')
        progress.set_title(_('Removing Account...'))
        progress.set_text(_('Trying to remove account...'))

        self.connect('button-clicked', self._on_button_clicked)
        self.connect('destroy', self._on_destroy)

        self.register_events([
            ('account-connected', ged.POSTGUI, self._on_account_connected),
            ('account-disconnected', ged.POSTGUI,
             self._on_account_disconnected),
        ])

        self._set_remove_from_server_checkbox()

        self.show_all()

    @overload
    def get_page(self, name: Literal['remove_choice']) -> RemoveChoice: ...

    @overload
    def get_page(self, name: Literal['error']) -> Error: ...

    @overload
    def get_page(self, name: Literal['success']) -> Success: ...

    def get_page(self, name: str) -> Page:
        return self._pages[name]

    @event_filter(['account'])
    def _on_account_connected(self, _event: AccountConnected) -> None:
        self._client = app.get_client(self.account)
        self._set_remove_from_server_checkbox()

    @event_filter(['account'])
    def _on_account_disconnected(self, _event: AccountDisconnected) -> None:
        self._set_remove_from_server_checkbox()

        if self._account_removed:
            self.show_page('success')
            app.app.remove_account(self.account)

    def _set_remove_from_server_checkbox(self) -> None:
        enabled = self._client is not None and self._client.state.is_available
        self.get_page('remove_choice').set_remove_from_server(enabled)

    def _on_button_clicked(self,
                           _assistant: Assistant,
                           button_name: str
                           ) -> None:
        page = self.get_current_page()
        if button_name == 'remove':
            if page == 'remove_choice':
                self.show_page('progress', Gtk.StackTransitionType.SLIDE_LEFT)
                self._on_remove()
            return

        if button_name == 'back':
            if page == 'error':
                self.show_page('remove_choice',
                               Gtk.StackTransitionType.SLIDE_RIGHT)
            return

        if button_name == 'close':
            self.destroy()

    def _on_remove(self, *args: Any) -> None:
        remove_choice_page = self.get_page('remove_choice')
        if remove_choice_page.remove_from_server:
            assert self._client is not None
            self._client.set_remove_account(True)
            self._client.get_module('Register').unregister(
                callback=self._on_remove_response)
            return

        if self._client is None or self._client.state.is_disconnected:
            app.app.remove_account(self.account)
            self.show_page('success')
            return

        self._client.disconnect(gracefully=True, reconnect=False)
        self._account_removed = True

    def _on_remove_response(self, task: Task) -> None:
        try:
            task.finish()
        except StanzaError as error:
            assert self._client is not None
            self._client.set_remove_account(False)

            error_text = to_user_string(error)
            self.get_page('error').set_text(error_text)
            self.show_page('error')
            return

        self._account_removed = True

    def _on_destroy(self, *args: Any) -> None:
        self._destroyed = True


class RemoveChoice(Page):
    def __init__(self, account: str) -> None:
        Page.__init__(self)
        self.title = _('Remove Account')

        heading = Gtk.Label(label=_('Remove Account'))
        heading.get_style_context().add_class('large-header')
        heading.set_max_width_chars(30)
        heading.set_line_wrap(True)
        heading.set_halign(Gtk.Align.CENTER)
        heading.set_justify(Gtk.Justification.CENTER)

        label = Gtk.Label(label=_('This will remove your account from Gajim.'))
        label.set_max_width_chars(50)
        label.set_line_wrap(True)
        label.set_halign(Gtk.Align.CENTER)
        label.set_justify(Gtk.Justification.CENTER)

        service = app.settings.get_account_setting(account, 'hostname')
        check_label = Gtk.Label()
        check_label.set_markup(
            _('Do you want to unregister your account on <b>%s</b> as '
              'well?') % service)
        check_label.set_max_width_chars(50)
        check_label.set_line_wrap(True)
        check_label.set_halign(Gtk.Align.CENTER)
        check_label.set_justify(Gtk.Justification.CENTER)
        check_label.set_margin_top(40)

        self._server = Gtk.CheckButton.new_with_mnemonic(
            _('_Unregister account from service'))
        self._server.set_halign(Gtk.Align.CENTER)

        self.pack_start(heading, False, True, 0)
        self.pack_start(label, False, True, 0)
        self.pack_start(check_label, False, True, 0)
        self.pack_start(self._server, False, True, 0)
        self.show_all()

    @property
    def remove_from_server(self) -> bool:
        return self._server.get_active()

    def set_remove_from_server(self, enabled: bool) -> None:
        self._server.set_sensitive(enabled)
        if enabled:
            self._server.set_tooltip_text('')
        else:
            self._server.set_active(False)
            self._server.set_tooltip_text(_('Account has to be connected'))

    def get_visible_buttons(self) -> list[str]:
        return ['remove']


class Error(ErrorPage):
    def __init__(self) -> None:
        ErrorPage.__init__(self)
        self.set_title(_('Account Removal Failed'))
        self.set_heading(_('Account Removal Failed'))

    def get_visible_buttons(self) -> list[str]:
        return ['back']


class Success(SuccessPage):
    def __init__(self) -> None:
        SuccessPage.__init__(self)
        self.set_title(_('Account Removed'))
        self.set_heading(_('Account Removed'))
        self.set_text(
            _('Your account has has been removed successfully.'))

    def get_visible_buttons(self) -> list[str]:
        return ['close']