# -----------------------------------------------------------------------
# Copyright (c) 2009  Jendrik Seipp
#
# RedNotebook 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; either version 2 of the License, or
# (at your option) any later version.
#
# RedNotebook 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 RedNotebook; if not, write to the Free Software Foundation, Inc.,
# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
# -----------------------------------------------------------------------

import datetime
import logging
import os

from gi.repository import GObject
from gi.repository import Gtk

from rednotebook.util import filesystem
from rednotebook.util import markup
from rednotebook.util import dates
from rednotebook.gui import customwidgets
from rednotebook.gui.customwidgets import Calendar, AssistantPage, \
    RadioButtonPage, PathChooserPage, Assistant


class DatePage(AssistantPage):
    def __init__(self, journal, *args, **kwargs):
        AssistantPage.__init__(self, *args, **kwargs)

        self.journal = journal

        self.all_days_button = Gtk.RadioButton(label=_('Export all days'))
        self.selected_text_button = Gtk.RadioButton(
            group=self.all_days_button)
        self.one_day_button = Gtk.RadioButton(
            label=_('Export currently visible day'),
            group=self.all_days_button)
        self.sel_days_button = Gtk.RadioButton(
            label=_('Export days in the selected time range'),
            group=self.all_days_button)

        self.pack_start(self.all_days_button, False, False, 0)
        self.pack_start(self.one_day_button, False, False, 0)
        self.pack_start(self.selected_text_button, False, False, 0)
        self.pack_start(self.sel_days_button, False, False, 0)

        label1 = Gtk.Label()
        label1.set_markup('<b>' + _('From:') + '</b>')
        label2 = Gtk.Label()
        label2.set_markup('<b>' + _('To:') + '</b>')

        show_week_numbers = self.journal.config.read('weekNumbers')
        self.calendar1 = Calendar(week_numbers=show_week_numbers)
        self.calendar2 = Calendar(week_numbers=show_week_numbers)

        vbox1 = Gtk.VBox()
        vbox2 = Gtk.VBox()
        vbox1.pack_start(label1, False, False, 0)
        vbox1.pack_start(self.calendar1, True, True, 0)
        vbox2.pack_start(label2, False, False, 0)
        vbox2.pack_start(self.calendar2, True, True, 0)

        hbox = Gtk.HBox()
        hbox.pack_start(vbox1, True, True, 0)
        hbox.pack_start(vbox2, True, True, 0)
        self.pack_start(hbox, True, True, 0)

        self.sel_days_button.connect('toggled', self._on_select_days_toggled)

        self.all_days_button.set_active(True)
        self._set_select_days(False)

    def _on_select_days_toggled(self, button):
        select = self.sel_days_button.get_active()
        self._set_select_days(select)

    def _set_select_days(self, sensitive):
        self.calendar1.set_sensitive(sensitive)
        self.calendar2.set_sensitive(sensitive)
        self.select_days = sensitive

    def export_all_days(self):
        return self.all_days_button.get_active()

    def export_selected_text(self):
        return self.selected_text_button.get_active()

    def get_date_range(self):
        if self.select_days:
            return (self.calendar1.get_date(), self.calendar2.get_date())
        return (self.journal.day.date,) * 2

    def refresh_dates(self):
        self.calendar1.set_date(datetime.date.today())
        self.calendar2.set_date(datetime.date.today())

    def prepare(self):
        selected_text_label = _('Export currently selected text')
        self.selected_text = self.journal.frame.day_text_field.get_selected_text()
        enable_selected_text_button = bool(self.selected_text and not self.journal.frame.preview_mode)
        self.selected_text_button.set_sensitive(enable_selected_text_button)
        if enable_selected_text_button:
            self.selected_text_button.set_label(selected_text_label)
        else:
            self.selected_text_button.set_label(
                selected_text_label + ' ' +
                _('(Only available when text is selected in edit mode)'))
            if self.selected_text_button.get_active():
                self.selected_text_button.set_active(False)
                self.all_days_button.set_active(True)


class ContentsPage(AssistantPage):
    def __init__(self, journal, assistant, *args, **kwargs):
        AssistantPage.__init__(self, *args, **kwargs)

        self.journal = journal
        self.assistant = assistant

        self.text_and_tags_button = Gtk.RadioButton(label=_('Export text and tags'))
        self.text_only_button = Gtk.RadioButton(label=_('Export text only'),
                                                group=self.text_and_tags_button)
        self.tags_only_button = Gtk.RadioButton(label=_('Export tags only'),
                                                group=self.text_and_tags_button)
        self.filter_tags_button = Gtk.CheckButton(label=_('Filter days by tags'))

        self.pack_start(self.text_and_tags_button, False, False, 0)
        self.pack_start(self.text_only_button, False, False, 0)
        self.pack_start(self.tags_only_button, False, False, 0)
        self.pack_start(Gtk.HSeparator(), False, False, 0)
        self.pack_start(self.filter_tags_button, False, False, 0)

        self.available_categories = customwidgets.CustomListView([(_('Available tags'), str)])
        self.selected_categories = customwidgets.CustomListView([(_('Selected tags'), str)])

        left_scroll = Gtk.ScrolledWindow()
        left_scroll.add(self.available_categories)

        right_scroll = Gtk.ScrolledWindow()
        right_scroll.add(self.selected_categories)

        self.select_button = Gtk.Button(_('Select') + ' >>')
        self.deselect_button = Gtk.Button('<< ' + _('Deselect'))

        self.select_button.connect('clicked', self.on_select_category)
        self.deselect_button.connect('clicked', self.on_deselect_category)

        centered_vbox = Gtk.VBox()
        centered_vbox.pack_start(self.select_button, True, False, 0)
        centered_vbox.pack_start(self.deselect_button, True, False, 0)

        vbox = Gtk.VBox()
        vbox.pack_start(centered_vbox, True, False, 0)

        hbox = Gtk.HBox()
        hbox.pack_start(left_scroll, True, True, 0)
        hbox.pack_start(vbox, False, False, 0)
        hbox.pack_start(right_scroll, True, True, 0)
        self.pack_start(hbox, True, True, 0)

        self.error_text = Gtk.Label(label='')
        self.error_text.set_alignment(0.0, 0.5)

        self.pack_end(self.error_text, False, False, 0)

        self.text_and_tags_button.set_active(True)
        self.filter_tags_button.connect('toggled', self.check_selection)

    def refresh_categories_list(self):
        model_available = Gtk.ListStore(GObject.TYPE_STRING)
        for category in self.journal.categories:
            model_available.append([category])
        self.available_categories.set_model(model_available)

        model_selected = Gtk.ListStore(GObject.TYPE_STRING)
        self.selected_categories.set_model(model_selected)

    def on_select_category(self, widget):
        selection = self.available_categories.get_selection()
        _, selected_iter = selection.get_selected()

        if selected_iter is not None:
            model_available = self.available_categories.get_model()
            model_selected = self.selected_categories.get_model()

            row = model_available[selected_iter]

            new_row = model_selected.insert(0)
            model_selected.set(new_row, 0, row[0])

            model_available.remove(selected_iter)

        self.check_selection()

    def on_deselect_category(self, widget):
        selection = self.selected_categories.get_selection()
        _, selected_iter = selection.get_selected()

        if selected_iter is not None:
            model_available = self.available_categories.get_model()
            model_selected = self.selected_categories.get_model()

            row = model_selected[selected_iter]

            new_row = model_available.insert(0)
            model_available.set(new_row, 0, row[0])

            model_selected.remove(selected_iter)

        self.check_selection()

    def set_error_text(self, text):
        self.error_text.set_markup('<b>' + text + '</b>')

    def is_text_included(self):
        return self.text_only_button.get_active() or self.text_and_tags_button.get_active()

    def is_tags_included(self):
        return self.tags_only_button.get_active() or self.text_and_tags_button.get_active()

    def is_filtered(self):
        return self.filter_tags_button.get_active()

    def get_categories(self):
        if not self.filter_tags_button.get_active():
            return self.journal.categories
        else:
            selected_categories = []
            model_selected = self.selected_categories.get_model()

            for row in model_selected:
                selected_categories.append(row[0])

            return selected_categories

    def check_selection(self, *args):
        if self.is_filtered() and not self.get_categories():
            error = _('When filtering by tags, you have to select at least one tag.')
            self.set_error_text(error)
            correct = False
        else:
            self.set_error_text('')
            correct = True

        select = self.filter_tags_button.get_active()
        self.available_categories.set_sensitive(select)
        self.selected_categories.set_sensitive(select)
        self.select_button.set_sensitive(select)
        self.deselect_button.set_sensitive(select)

        self.assistant.set_page_complete(self.assistant.page3, correct)


class SummaryPage(AssistantPage):
    def __init__(self, *args, **kwargs):
        AssistantPage.__init__(self, *args, **kwargs)

        self.settings = []

    def prepare(self):
        text = _('You have selected the following settings:')
        self.set_header(text)
        self.clear()

    def add_setting(self, setting, value):
        label = Gtk.Label()
        label.set_markup('<b>{}:</b> {}'.format(setting, value))
        label.set_alignment(0.0, 0.5)
        label.show()
        self.pack_start(label, False, False, 0)
        self.settings.append(label)

    def clear(self):
        for setting in self.settings:
            self.remove(setting)
        self.settings = []


class ExportAssistant(Assistant):
    def __init__(self, *args, **kwargs):
        Assistant.__init__(self, *args, **kwargs)
        self.set_modal(True)

        self.exporters = get_exporters()

        self.set_title(_('Export Assistant'))

        def add_space():
            self.page1.pack_start(Gtk.Label(''), False, False, 0)

        self.page1 = RadioButtonPage()
        text = '\n'.join([
            _('Welcome to the Export Assistant.'),
            _('This wizard will help you to export your journal to various formats.'),
            _('You can select the days you want to export and where the output will be saved.')])
        welcome_label = Gtk.Label(text)
        self.page1.pack_start(welcome_label, False, False, 0)
        add_space()
        for exporter in self.exporters:
            name = exporter.NAME
            desc = exporter.DESCRIPTION
            self.page1.add_radio_option(exporter, name, desc)
        add_space()
        pdf_label = Gtk.Label(_('PDF: export to HTML, open in browser and print to PDF file'))
        pdf_label.set_halign(Gtk.Align.START)
        self.page1.pack_start(pdf_label, False, False, 0)
        self.append_page(self.page1)
        self.set_page_title(self.page1, _('Select Export Format') + ' (1/5)')
        self.set_page_complete(self.page1, True)

        self.page2 = DatePage(self.journal)
        self.append_page(self.page2)
        self.set_page_title(self.page2, _('Select Date Range') + ' (2/5)')
        self.set_page_complete(self.page2, True)

        self.page3 = ContentsPage(self.journal, self)
        self.append_page(self.page3)
        self.set_page_title(self.page3, _('Select Contents') + ' (3/5)')
        self.set_page_complete(self.page3, True)
        self.page3.check_selection()

        self.page4 = PathChooserPage(self)
        self.append_page(self.page4)
        self.set_page_title(self.page4, _('Select Export Path') + ' (4/5)')
        self.set_page_complete(self.page4, True)

        self.page5 = SummaryPage()
        self.append_page(self.page5)
        self.set_page_title(self.page5, _('Summary') + ' (5/5)')
        self.set_page_type(self.page5, Gtk.AssistantPageType.CONFIRM)
        self.set_page_complete(self.page5, True)

        self.exporter = None
        self.path = None
        self.set_forward_page_func(self.pageforward)

    def pageforward(self, page):
        if page == 2 and self.page2.export_selected_text():
            return 4
        else:
            return page + 1

    def run(self):
        self.page2.refresh_dates()
        self.page3.refresh_categories_list()
        self.show_all()

    def _on_close(self, assistant):
        '''
        Do the export
        '''
        self.hide()
        self.export()

    def _on_prepare(self, assistant, page):
        '''
        Called when a new page should be prepared, before it is shown
        '''
        if page == self.page2:
            # Date Range
            self.exporter = self.page1.get_selected_object()
            self.page2.prepare()
        elif page == self.page3:
            # Categories
            start_date, end_date = self.page2.get_date_range()
            if not self.page2.export_all_days() and start_date == end_date:
                self.page3.filter_tags_button.set_active(False)
                self.page3.filter_tags_button.set_sensitive(False)
            else:
                self.page3.filter_tags_button.set_sensitive(True)
        elif page == self.page4:
            # Path
            self.page4.prepare(self.exporter)
        elif page == self.page5:
            # Summary
            self.path = self.page4.get_selected_path()
            self.page5.prepare()
            self.export_all_days = self.page2.export_all_days()
            self.export_selected_text = self.page2.export_selected_text()
            self.is_filtered = self.page3.is_filtered()
            self.exported_categories = self.page3.get_categories()

            self.page5.add_setting(_('Format'), self.exporter.NAME)
            self.page5.add_setting(_('Export all days'), self.yes_no(self.export_all_days))
            if not self.export_all_days:
                start_date, end_date = self.page2.get_date_range()
                if start_date == end_date:
                    self.page5.add_setting(_('Date'), start_date)
                    self.page5.add_setting(
                        _('Export selected text only'),
                        self.yes_no(self.export_selected_text))
                else:
                    self.page5.add_setting(_('Start date'), start_date)
                    self.page5.add_setting(_('End date'), end_date)
            if self.export_selected_text:
                self.exported_categories = []
            else:
                self.page5.add_setting(_('Include text'), self.yes_no(self.page3.is_text_included()))
                self.page5.add_setting(_('Include tags'), self.yes_no(self.page3.is_tags_included()))
            if self.is_filtered:
                self.page5.add_setting(_('Filtered by tags'), ', '.join(self.exported_categories))
            self.page5.add_setting(_('Export path'), self.path)

    def yes_no(self, value):
        return _('Yes') if value else _('No')

    def get_export_string(self, target):
        if self.export_selected_text and self.page2.selected_text:
            markup_string = self.page2.selected_text
        else:
            if self.export_all_days:
                export_days = self.journal.days
            else:
                export_days = self.journal.get_days_in_date_range(*self.page2.get_date_range())

            selected_categories = self.exported_categories
            logging.debug('Selected Categories for Inclusion: %s' % selected_categories)

            markup_strings_for_each_day = []
            for day in export_days:
                include_day = True
                if self.is_filtered:
                    include_day = False
                    catagory_pairs = day.get_category_content_pairs()
                    for category in selected_categories:
                        if category in catagory_pairs:
                            include_day = True
                if include_day:
                    date_format = self.journal.config.read('exportDateFormat')
                    date_string = dates.format_date(date_format, day.date)
                    day_markup = markup.get_markup_for_day(day,
                                                           target,
                                                           with_text=self.page3.is_text_included(),
                                                           with_tags=self.page3.is_tags_included(),
                                                           categories=selected_categories,
                                                           date=date_string)
                    markup_strings_for_each_day.append(day_markup)

            markup_string = ''.join(markup_strings_for_each_day)

        return self.journal.convert(markup_string, target, options={'toc': 0})

    def export(self):
        format = self.exporter.FORMAT
        export_string = self.get_export_string(format)
        filesystem.write_file(self.path, export_string)
        self.journal.show_message(_('Content exported to %s') % self.path)


class Exporter:
    NAME = 'Which format do we use?'
    # Short description of how we export
    DESCRIPTION = ''
    # Export destination
    PATHTEXT = ''
    PATHTYPE = 'NEWFILE'
    EXTENSION = None

    @classmethod
    def is_available(_cls):
        '''
        This function should be implemented by the subclasses that may
        not be available

        If their requirements are not met, they return False
        '''
        return True

    def export(self):
        '''
        This function has to be implemented by all subclasses

        It should *yield* ImportDay objects
        '''

    @property
    def DEFAULTPATH(self):
        return os.path.join(
            os.path.expanduser('~'),
            'RedNotebook-Export_{}.{}'.format(datetime.date.today(), self.EXTENSION))


class PlainTextExporter(Exporter):
    NAME = _('Plain Text')
    EXTENSION = 'txt'
    FORMAT = 'txt'


class HtmlExporter(Exporter):
    NAME = 'HTML'
    EXTENSION = 'html'
    FORMAT = 'xhtml'


class LatexExporter(Exporter):
    NAME = 'Latex'
    EXTENSION = 'tex'
    FORMAT = 'tex'


def get_exporters():
    exporters = [PlainTextExporter, HtmlExporter, LatexExporter]

    # Instantiate exporters
    return [exporter() for exporter in exporters]
