# This file is part of Gajim.
#
# SPDX-License-Identifier: GPL-3.0-only

from __future__ import annotations

from typing import cast
from typing import Literal
from typing import overload

import logging
from datetime import datetime
from datetime import timedelta
from datetime import timezone

from gi.repository import GLib
from gi.repository import Gtk
from gi.repository import Pango
from nbxmpp.errors import MalformedStanzaError
from nbxmpp.errors import StanzaError
from nbxmpp.task import Task

from gajim.common import app
from gajim.common import ged
from gajim.common.const import ArchiveState
from gajim.common.events import ArchivingIntervalFinished
from gajim.common.events import RawMamMessageReceived
from gajim.common.ged import EventHelper
from gajim.common.i18n import _
from gajim.common.util.decorators import event_filter

from gajim.gtk.assistant import Assistant
from gajim.gtk.assistant import Page
from gajim.gtk.assistant import SuccessPage
from gajim.gtk.util import iterate_listbox_children

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


class HistorySyncAssistant(Assistant, EventHelper):
    def __init__(self, account: str) -> None:
        Assistant.__init__(self, width=600, transient_for=app.window)
        EventHelper.__init__(self)
        self.window.set_name('HistorySyncAssistant')

        self.account = account
        self._client = app.get_client(account)

        self._timedelta: timedelta | None = None
        self._now = datetime.now(timezone.utc)
        self._query_id: str | None = None
        self._start: datetime = ArchiveState.ALL
        self._end: datetime | None = None

        mam_start = None
        archive = app.storage.archive.get_mam_archive_state(
            account, self._client.get_own_jid().new_as_bare())

        if archive is not None and archive.from_stanza_ts is not None:
            mam_start = archive.from_stanza_ts

        if mam_start is None:
            self._current_start = self._now
        else:
            self._current_start = mam_start

        self.add_button('synchronize', _('Synchronize'), 'suggested-action')
        self.add_button('close', _('Close'))
        self.set_button_visible_func(self._visible_func)

        self.add_pages({
            'select': SelectTime(self._now, self._current_start),
            'progress': Progress(),
        })

        self.add_default_page('success')
        success_page = self.get_page('success')
        success_page.set_title(_('Synchronize Chat History'))
        success_page.set_heading(_('Finished'))

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

        # pylint: disable=line-too-long
        self.register_events([
            ('archiving-interval-finished', ged.GUI1, self._received_finished),
            ('raw-mam-message-received',
             ged.PRECORE,
             self._mam_message_received),
        ])
        # pylint: enable=line-too-long

        if mam_start == ArchiveState.ALL:
            success_page.set_text(
                _('Gajim is fully synchronized with the archive.'))
            self.show_page('success')

        self.show_all()

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

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

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

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

    @staticmethod
    def _visible_func(_assistant: Assistant, page_name: str) -> list[str]:
        if page_name == 'select':
            return ['close', 'synchronize']

        if page_name == 'progress':
            return ['close']

        if page_name == 'success':
            return ['close']

        raise ValueError(f'page {page_name} unknown')

    def _on_button_clicked(self,
                           _assistant: Assistant,
                           button_name: str
                           ) -> None:
        if button_name == 'synchronize':
            self._prepare_query()
            self.show_page('progress', Gtk.StackTransitionType.SLIDE_LEFT)
            return

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

    def _prepare_query(self) -> None:
        select_time_page = self.get_page('select')
        self._timedelta = select_time_page.get_timedelta()
        if self._timedelta is not None:
            self._start = self._now - self._timedelta
        self._end = self._current_start

        log.info('Get mam_start_date: %s', self._current_start)
        log.info('Now: %s', self._now)
        log.info('Start: %s', self._start)
        log.info('End: %s', self._end)

        # Archive count query
        self._client.get_module('MAM').make_query(
            self._client.get_own_jid().bare,
            start=self._start,
            end=self._end,
            max_=0,
            callback=self._received_count)

    def _received_count(self, task: Task) -> None:
        try:
            result = task.finish()
        except (StanzaError, MalformedStanzaError):
            return

        if result.rsm.count is not None:
            self.get_page('progress').set_count(int(result.rsm.count))
        mam_module = self._client.get_module('MAM')
        assert self._start is not None
        assert self._end is not None
        self._query_id = mam_module.request_archive_interval(
            self._start, self._end)

    @event_filter(['account'])
    def _received_finished(self, event: ArchivingIntervalFinished) -> None:
        if event.query_id != self._query_id:
            return
        self._query_id = None
        log.info('Query finished')
        progress_page = self.get_page('progress')
        GLib.idle_add(progress_page.set_finished)
        received_count = progress_page.get_received_count()
        success_page = self.get_page('success')
        success_page.set_text(_('Finished synchronising chat history:\n'
                                '%s messages downloaded') % received_count)
        self.show_page('success')

    @event_filter(['account'])
    def _mam_message_received(self, event: RawMamMessageReceived) -> None:
        if self._query_id != event.properties.mam.query_id:
            return

        log.debug('Received message')
        progress_page = self.get_page('progress')
        GLib.idle_add(progress_page.set_fraction)


class SelectTime(Page):
    def __init__(self,
                 now: datetime,
                 current_start: datetime
                 ) -> None:
        Page.__init__(self)
        self.title = _('Synchronize Chat History')

        self.complete = False
        self._timedelta: timedelta | None = None

        heading = Gtk.Label()
        heading.get_style_context().add_class('large-header')
        heading.set_max_width_chars(30)
        heading.set_wrap(True)
        heading.set_wrap_mode(Pango.WrapMode.WORD)
        heading.set_halign(Gtk.Align.CENTER)
        heading.set_justify(Gtk.Justification.CENTER)
        heading.set_text(_('Synchronize Chat History'))

        label = Gtk.Label(
            label=_('How far back should the chat history be synchronized?'))
        label.set_halign(Gtk.Align.CENTER)
        label.set_wrap(True)
        label.set_wrap_mode(Pango.WrapMode.WORD)
        label.set_max_width_chars(40)

        listbox = Gtk.ListBox()
        listbox.set_hexpand(False)
        listbox.set_halign(Gtk.Align.CENTER)
        listbox.append(TimeOption(_('One Month'), timedelta(days=30)))
        listbox.append(TimeOption(_('Three Months'), timedelta(days=90)))
        listbox.append(TimeOption(_('One Year'), timedelta(days=365)))
        listbox.append(TimeOption(_('Everything')))
        self._connect(listbox, 'row-selected', self._on_row_selected)

        for row in cast(list[TimeOption], iterate_listbox_children(listbox)):
            delta = row.get_timedelta()
            if delta is None:
                continue
            if now - delta > current_start:
                row.set_activatable(False)
                row.set_selectable(False)

        self.append(heading)
        self.append(label)
        self.append(listbox)

    def _on_row_selected(self, _listbox: Gtk.ListBox, row: TimeOption) -> None:
        self._timedelta = row.get_timedelta()
        self.complete = True
        self.update_page_complete()

    def get_timedelta(self) -> timedelta | None:
        return self._timedelta

    def get_default_button(self) -> str:
        return 'synchronize'


class Progress(Page):
    def __init__(self) -> None:
        Page.__init__(self)
        self.title = _('Synchronizing Chat History…')

        self._count = 0
        self._received = 0

        image = Gtk.Image.new_from_icon_name('folder-download-symbolic')
        image.set_pixel_size(64)

        self._progress_bar = Gtk.ProgressBar()
        self._progress_bar.set_show_text(True)
        self._progress_bar.set_text(_('Connecting...'))
        self._progress_bar.set_pulse_step(0.1)
        self._progress_bar.set_vexpand(True)
        self._progress_bar.set_valign(Gtk.Align.CENTER)

        self.append(image)
        self.append(self._progress_bar)

    def set_fraction(self) -> None:
        self._received += 1
        if self._count:
            self._progress_bar.set_fraction(self._received / self._count)
            self._progress_bar.set_text(
                _('%(received)s of %(max)s') % {
                    'received': self._received,
                    'max': self._count})
        else:
            self._progress_bar.pulse()
            self._progress_bar.set_text(
                _('Downloaded %s messages') % self._received)

    def set_count(self, count: int) -> None:
        self._count = count

    def set_finished(self) -> None:
        self._progress_bar.set_fraction(1)

    def get_received_count(self) -> int:
        return self._received


class TimeOption(Gtk.ListBoxRow):
    def __init__(self, text: str, months: timedelta | None = None) -> None:
        Gtk.ListBoxRow.__init__(self)
        label = Gtk.Label(label=text)
        self.set_child(label)

        self._timedelta = months

    def get_timedelta(self) -> timedelta | None:
        return self._timedelta
