calibre/src/calibre/gui2/tweak_book/ui.py

#!/usr/bin/env python


__license__ = 'GPL v3'
__copyright__ = '2013, Kovid Goyal <kovid at kovidgoyal.net>'

import os
from functools import partial
from gettext import pgettext
from itertools import product
from qt.core import (
    QAction, QApplication, QColor, QDockWidget, QEvent, QHBoxLayout, QIcon, QImage,
    QLabel, QMenu, QPalette, QPixmap, QSize, QStackedWidget, Qt, QTabWidget, QTimer,
    QUrl, QVBoxLayout, QWidget, pyqtSignal, QMenuBar
)

from calibre import prepare_string_for_xml, prints
from calibre.constants import (
    DEBUG, __appname__, builtin_colors_dark, builtin_colors_light, get_version,
    ismacos
)
from calibre.customize.ui import find_plugin
from calibre.gui2 import elided_text, open_url
from calibre.gui2.keyboard import Manager as KeyboardManager
from calibre.gui2.main_window import MainWindow
from calibre.gui2.throbber import ThrobbingButton
from calibre.gui2.tweak_book import (
    actions, capitalize, current_container, editors, toolbar_actions, tprefs,
    update_mark_text_action
)
from calibre.gui2.tweak_book.boss import Boss
from calibre.gui2.tweak_book.char_select import CharSelect
from calibre.gui2.tweak_book.check import Check
from calibre.gui2.tweak_book.check_links import CheckExternalLinks
from calibre.gui2.tweak_book.editor.insert_resource import InsertImage
from calibre.gui2.tweak_book.editor.widget import register_text_editor_actions
from calibre.gui2.tweak_book.file_list import FileListWidget
from calibre.gui2.tweak_book.function_replace import DebugOutput
from calibre.gui2.tweak_book.job import BlockingJob
from calibre.gui2.tweak_book.live_css import LiveCSS
from calibre.gui2.tweak_book.manage_fonts import ManageFonts
from calibre.gui2.tweak_book.plugin import create_plugin_actions, install_plugin
from calibre.gui2.tweak_book.preview import Preview
from calibre.gui2.tweak_book.reports import Reports
from calibre.gui2.tweak_book.search import SavedSearches, SearchPanel
from calibre.gui2.tweak_book.spell import SpellCheck
from calibre.gui2.tweak_book.text_search import TextSearch
from calibre.gui2.tweak_book.toc import TOCViewer
from calibre.gui2.tweak_book.undo import CheckpointView
from calibre.utils.icu import ord_string, sort_key
from calibre.utils.localization import (
    localize_user_manual_link, localize_website_link
)
from calibre.utils.unicode_names import character_name_from_code
from polyglot.builtins import iteritems, itervalues


def open_donate():
    open_url(QUrl(localize_website_link('https://calibre-ebook.com/donate')))


class Central(QStackedWidget):  # {{{

    ' The central widget, hosts the editors '

    current_editor_changed = pyqtSignal()
    close_requested = pyqtSignal(object)

    def __init__(self, parent=None):
        QStackedWidget.__init__(self, parent)
        self.welcome = w = QLabel('<p>'+_(
            'Double click a file in the left panel to start editing'
            ' it.'))
        self.addWidget(w)
        w.setWordWrap(True)
        w.setAlignment(Qt.AlignmentFlag.AlignTop | Qt.AlignmentFlag.AlignHCenter)

        self.container = c = QWidget(self)
        self.addWidget(c)
        l = c.l = QVBoxLayout(c)
        c.setLayout(l)
        l.setContentsMargins(0, 0, 0, 0)
        self.editor_tabs = t = QTabWidget(c)
        l.addWidget(t)
        t.setDocumentMode(True)
        t.setTabsClosable(True)
        t.setMovable(True)
        pal = self.palette()
        if pal.color(QPalette.ColorRole.WindowText).lightness() > 128:
            i = QImage(I('modified.png'))
            i.invertPixels()
            self.modified_icon = QIcon(QPixmap.fromImage(i))
        else:
            self.modified_icon = QIcon(I('modified.png'))
        self.editor_tabs.currentChanged.connect(self.current_editor_changed)
        self.editor_tabs.tabCloseRequested.connect(self._close_requested)
        self.search_panel = SearchPanel(self)
        l.addWidget(self.search_panel)
        self.restore_state()
        self.editor_tabs.tabBar().installEventFilter(self)

    def _close_requested(self, index):
        editor = self.editor_tabs.widget(index)
        self.close_requested.emit(editor)

    def add_editor(self, name, editor):
        fname = name.rpartition('/')[2]
        index = self.editor_tabs.addTab(editor, fname)
        self.editor_tabs.setTabToolTip(index, _('Full path:') + ' ' + name)
        editor.modification_state_changed.connect(self.editor_modified)

    @property
    def tab_order(self):
        ans = []
        rmap = {v:k for k, v in iteritems(editors)}
        for i in range(self.editor_tabs.count()):
            name = rmap.get(self.editor_tabs.widget(i))
            if name is not None:
                ans.append(name)
        return ans

    def rename_editor(self, editor, name):
        for i in range(self.editor_tabs.count()):
            if self.editor_tabs.widget(i) is editor:
                fname = name.rpartition('/')[2]
                self.editor_tabs.setTabText(i, fname)
                self.editor_tabs.setTabToolTip(i, _('Full path:') + ' ' + name)

    def show_editor(self, editor):
        self.setCurrentIndex(1)
        self.editor_tabs.setCurrentWidget(editor)

    def close_editor(self, editor):
        for i in range(self.editor_tabs.count()):
            if self.editor_tabs.widget(i) is editor:
                self.editor_tabs.removeTab(i)
                if self.editor_tabs.count() == 0:
                    self.setCurrentIndex(0)
                return True
        return False

    def editor_modified(self, *args):
        tb = self.editor_tabs.tabBar()
        for i in range(self.editor_tabs.count()):
            editor = self.editor_tabs.widget(i)
            modified = getattr(editor, 'is_modified', False)
            tb.setTabIcon(i, self.modified_icon if modified else QIcon())

    def close_current_editor(self):
        ed = self.current_editor
        if ed is not None:
            self.close_requested.emit(ed)

    def close_all_but_current_editor(self):
        self.close_all_but(self.current_editor)

    def close_to_right_of_current_editor(self):
        self.close_to_right(self.current_editor)

    def close_all_but(self, ed):
        close = []
        if ed is not None:
            for i in range(self.editor_tabs.count()):
                q = self.editor_tabs.widget(i)
                if q is not None and q is not ed:
                    close.append(q)
        for q in close:
            self.close_requested.emit(q)

    def close_to_right(self, ed):
        close = []
        if ed is not None:
            found = False
            for i in range(self.editor_tabs.count()):
                q = self.editor_tabs.widget(i)
                if found:
                    close.append(q)
                elif q is ed:
                    found = True
        for q in close:
            self.close_requested.emit(q)

    @property
    def current_editor(self):
        return self.editor_tabs.currentWidget()

    def save_state(self):
        tprefs.set('search-panel-visible', self.search_panel.isVisible())
        self.search_panel.save_state()
        for ed in itervalues(editors):
            ed.save_state()
        if self.current_editor is not None:
            self.current_editor.save_state()  # Ensure the current editor saves it state last

    def restore_state(self):
        self.search_panel.setVisible(tprefs.get('search-panel-visible', False))
        self.search_panel.restore_state()

    def show_find(self):
        self.search_panel.show_panel()

    def pre_fill_search(self, text):
        self.search_panel.pre_fill(text)

    def eventFilter(self, obj, event):
        base = super()
        if obj is not self.editor_tabs.tabBar() or event.type() != QEvent.Type.MouseButtonPress or event.button() not in (
                Qt.MouseButton.RightButton, Qt.MouseButton.MidButton):
            return base.eventFilter(obj, event)
        index = self.editor_tabs.tabBar().tabAt(event.pos())
        if index < 0:
            return base.eventFilter(obj, event)
        if event.button() == Qt.MouseButton.MidButton:
            self._close_requested(index)
        ed = self.editor_tabs.widget(index)
        if ed is not None:
            menu = QMenu(self)
            menu.addAction(actions['close-current-tab'].icon(), _('Close tab'), partial(self.close_requested.emit, ed))
            menu.addSeparator()
            menu.addAction(actions['close-all-but-current-tab'].icon(), _('Close other tabs'), partial(self.close_all_but, ed))
            menu.addAction(actions['close-tabs-to-right-of'].icon(), _('Close tabs to the right of this tab'), partial(self.close_to_right, ed))
            menu.exec(self.editor_tabs.tabBar().mapToGlobal(event.pos()))

        return True
# }}}


class CursorPositionWidget(QWidget):  # {{{

    def __init__(self, parent):
        QWidget.__init__(self, parent)
        self.l = QHBoxLayout(self)
        self.setLayout(self.l)
        self.la = QLabel('')
        self.l.addWidget(self.la)
        self.l.setContentsMargins(0, 0, 0, 0)
        f = self.la.font()
        f.setBold(False)
        self.la.setFont(f)

    def update_position(self, line=None, col=None, character=None):
        if line is None:
            self.la.setText('')
        else:
            try:
                name = character_name_from_code(ord_string(character)[0]) if character and tprefs['editor_show_char_under_cursor'] else None
            except Exception:
                name = None
            text = _('Line: {0} : {1}').format(line, col)
            if not name:
                name = {'\t':'TAB'}.get(character, None)
            if name and tprefs['editor_show_char_under_cursor']:
                text = name + ' : ' + text
            self.la.setText(text)
# }}}


def install_new_plugins():
    from calibre.utils.config import JSONConfig
    prefs = JSONConfig('newly-installed-editor-plugins')
    pl = prefs.get('newly_installed_plugins', ())
    if pl:
        for name in pl:
            plugin = find_plugin(name)
            if plugin is not None:
                install_plugin(plugin)
        prefs['newly_installed_plugins'] = []


class MessagePopup(QLabel):

    undo_requested = pyqtSignal()

    def __init__(self, parent):
        QLabel.__init__(self, parent)
        self.setFocusPolicy(Qt.FocusPolicy.NoFocus)
        if QApplication.instance().is_dark_theme:
            c = builtin_colors_dark['green']
        else:
            c = builtin_colors_light['green']
        self.color = self.palette().color(QPalette.ColorRole.WindowText).name()
        bg = QColor(c).getRgb()
        self.setStyleSheet(f'''QLabel {{
            background-color: rgba({bg[0]}, {bg[1]}, {bg[2]}, 0.85);
            border-radius: 4px;
            color: {self.color};
            padding: 0.5em;
        }}'''
        )
        self.linkActivated.connect(self.link_activated)
        self.close_timer = t = QTimer()
        t.setSingleShot(True)
        t.timeout.connect(self.hide)
        self.setMouseTracking(True)
        self.hide()

    def mouseMoveEvent(self, ev):
        self.close_timer.start()
        return super().mouseMoveEvent(ev)

    def link_activated(self, link):
        self.hide()
        if link.startswith('undo://'):
            self.undo_requested.emit()

    def __call__(self, text='Testing message popup', show_undo=True, timeout=5000, has_markup=False):
        text = '<p>' + (text if has_markup else prepare_string_for_xml(text))
        if show_undo:
            text += '\xa0\xa0<a style="text-decoration: none" href="undo://me.com">{}</a>'.format(_('Undo'))
        text += f'\xa0\xa0<a style="text-decoration: none; color: {self.color}" href="close://me.com">✖</a>'
        self.setText(text)
        self.resize(self.sizeHint())
        self.position_in_parent()
        self.show()
        self.raise_()
        self.close_timer.start(timeout)

    def position_in_parent(self):
        p = self.parent()
        self.move((p.width() - self.width()) // 2, 25)


class Main(MainWindow):

    APP_NAME = _('Edit book')
    STATE_VERSION = 0
    undo_requested = pyqtSignal()

    def __init__(self, opts, notify=None):
        MainWindow.__init__(self, opts, disable_automatic_gc=True)
        self.message_popup = MessagePopup(self)
        self.message_popup.undo_requested.connect(self.undo_requested)
        try:
            install_new_plugins()
        except Exception:
            import traceback
            traceback.print_exc()
        self.setWindowTitle(self.APP_NAME)
        self.boss = Boss(self, notify=notify)
        self.setWindowIcon(QIcon(I('tweak.png')))
        self.opts = opts
        self.path_to_ebook = None
        self.container = None
        self.current_metadata = None
        self.blocking_job = BlockingJob(self)
        self.keyboard = KeyboardManager(self, config_name='shortcuts/tweak_book')

        self.central = Central(self)
        self.setCentralWidget(self.central)
        self.check_book = Check(self)
        self.spell_check = SpellCheck(parent=self)
        self.toc_view = TOCViewer(self)
        self.text_search = TextSearch(self)
        self.saved_searches = SavedSearches(self)
        self.image_browser = InsertImage(self, for_browsing=True)
        self.reports = Reports(self)
        self.check_external_links = CheckExternalLinks(self)
        self.insert_char = CharSelect(self)
        self.manage_fonts = ManageFonts(self)
        self.sr_debug_output = DebugOutput(self)

        self.create_actions()
        self.create_toolbars()
        self.create_docks()
        self.create_menubar()

        self.status_bar = self.statusBar()
        self.status_bar.addPermanentWidget(self.boss.save_manager.status_widget)
        self.cursor_position_widget = CursorPositionWidget(self)
        self.status_bar.addPermanentWidget(self.cursor_position_widget)
        self.status_bar_default_msg = la = QLabel(' ' + _('{0} {1} created by {2}').format(__appname__, get_version(), 'Kovid Goyal'))
        la.base_template = str(la.text())
        self.status_bar.addWidget(la)

        self.boss(self)
        g = self.screen().availableSize()
        self.resize(g.width()-50, g.height()-50)

        self.apply_settings()
        QTimer.singleShot(0, self.restore_state)

    def apply_settings(self):
        self.keyboard.finalize()
        self.setDockNestingEnabled(tprefs['nestable_dock_widgets'])
        for v, h in product(('top', 'bottom'), ('left', 'right')):
            p = f'dock_{v}_{h}'
            pref = tprefs[p] or tprefs.defaults[p]
            area = getattr(Qt.DockWidgetArea, '%sDockWidgetArea' % capitalize({'vertical':h, 'horizontal':v}[pref]))
            self.setCorner(getattr(Qt.Corner, '%s%sCorner' % tuple(map(capitalize, (v, h)))), area)
        self.preview.apply_settings()
        self.live_css.apply_theme()
        for bar in (self.global_bar, self.tools_bar, self.plugins_bar):
            bar.setIconSize(QSize(tprefs['toolbar_icon_size'], tprefs['toolbar_icon_size']))

    def show_status_message(self, msg, timeout=5):
        self.status_bar.showMessage(msg, int(timeout*1000))

    def elided_text(self, text, width=300):
        return elided_text(text, font=self.font(), width=width)

    @property
    def editor_tabs(self):
        return self.central.editor_tabs

    def create_actions(self):
        group = _('Global actions')

        def reg(icon, text, target, sid, keys, description, toolbar_allowed=False):
            if not isinstance(icon, QIcon):
                icon = QIcon(I(icon))
            ac = actions[sid] = QAction(icon, text, self) if icon else QAction(text, self)
            ac.setObjectName('action-' + sid)
            if toolbar_allowed:
                toolbar_actions[sid] = ac
            if target is not None:
                ac.triggered.connect(target)
            if isinstance(keys, str):
                keys = (keys,)
            self.keyboard.register_shortcut(
                sid, str(ac.text()).replace('&', ''), default_keys=keys, description=description, action=ac, group=group)
            self.addAction(ac)
            return ac

        def treg(icon, text, target, sid, keys, description):
            return reg(icon, text, target, sid, keys, description, toolbar_allowed=icon is not None)

        self.action_new_file = treg('document-new.png', _('&New file (images/fonts/HTML/etc.)'), self.boss.add_file,
                                   'new-file', (), _('Create a new file in the current book'))
        self.action_import_files = treg('document-import.png', _('&Import files into book'), self.boss.add_files, 'new-files', (), _('Import files into book'))
        self.action_open_book = treg('document_open.png', _('&Open book'), self.boss.open_book, 'open-book', 'Ctrl+O', _('Open a book'))
        self.action_open_book_folder = treg('mimetypes/dir.png', _('Open &folder (unzipped EPUB) as book'), partial(self.boss.open_book, open_folder=True),
                                            'open-folder-as-book', (), _('Open a folder (unzipped EPUB) as a book'))
        self.action_edit_next_file = treg('arrow-down.png', _('Edit &next file'), partial(self.boss.edit_next_file, backwards=False),
                'edit-next-file', 'Ctrl+Alt+Down', _('Edit the next file in the spine'))
        self.action_edit_previous_file = treg('arrow-up.png', _('Edit &previous file'), partial(self.boss.edit_next_file, backwards=True),
                'edit-previous-file', 'Ctrl+Alt+Up', _('Edit the previous file in the spine'))
        # Qt does not generate shortcut overrides for cmd+arrow on os x which
        # means these shortcuts interfere with editing
        self.action_global_undo = treg('back.png', _('&Revert to before'), self.boss.do_global_undo, 'global-undo', () if ismacos else 'Ctrl+Left',
                                      _('Revert book to before the last action (Undo)'))
        self.action_global_redo = treg('forward.png', _('&Revert to after'), self.boss.do_global_redo, 'global-redo', () if ismacos else 'Ctrl+Right',
                                      _('Revert book state to after the next action (Redo)'))
        self.action_save = treg('save.png', _('&Save'), self.boss.save_book, 'save-book', 'Ctrl+S', _('Save book'))
        self.action_save.setEnabled(False)
        self.action_save_copy = treg('save.png', _('Save a &copy'), self.boss.save_copy, 'save-copy', 'Ctrl+Alt+S', _('Save a copy of the book'))
        self.action_quit = treg('window-close.png', _('&Quit'), self.boss.quit, 'quit', 'Ctrl+Q', _('Quit'))
        self.action_preferences = treg('config.png', _('&Preferences'), self.boss.preferences, 'preferences', 'Ctrl+P', _('Preferences'))
        self.action_new_book = treg('plus.png', _('Create new, &empty book'), self.boss.new_book, 'new-book', (), _('Create a new, empty book'))
        self.action_import_book = treg('add_book.png', _('&Import an HTML or DOCX file as a new book'),
                                      self.boss.import_book, 'import-book', (), _('Import an HTML or DOCX file as a new book'))
        self.action_quick_edit = treg('modified.png', _('&Quick open a file to edit'), self.boss.quick_open, 'quick-open', ('Ctrl+T'), _(
            'Quickly open a file from the book to edit it'))

        # Editor actions
        group = _('Editor actions')
        self.action_editor_undo = reg('edit-undo.png', _('&Undo'), self.boss.do_editor_undo, 'editor-undo', 'Ctrl+Z',
                                      _('Undo typing'))
        self.action_editor_redo = reg('edit-redo.png', _('R&edo'), self.boss.do_editor_redo, 'editor-redo', 'Ctrl+Y',
                                      _('Redo typing'))
        self.action_editor_cut = reg('edit-cut.png', _('Cut &text'), self.boss.do_editor_cut, 'editor-cut', ('Ctrl+X', 'Shift+Delete', ),
                                      _('Cut text'))
        self.action_editor_copy = reg('edit-copy.png', _('&Copy to clipboard'), self.boss.do_editor_copy, 'editor-copy', ('Ctrl+C', 'Ctrl+Insert'),
                                      _('Copy to clipboard'))
        self.action_editor_paste = reg('edit-paste.png', _('P&aste from clipboard'), self.boss.do_editor_paste, 'editor-paste', ('Ctrl+V', 'Shift+Insert', ),
                                      _('Paste from clipboard'))
        self.action_editor_cut.setEnabled(False)
        self.action_editor_copy.setEnabled(False)
        self.action_editor_undo.setEnabled(False)
        self.action_editor_redo.setEnabled(False)

        # Tool actions
        group = _('Tools')
        self.action_toc = treg('toc.png', _('&Edit Table of Contents'), self.boss.edit_toc, 'edit-toc', (), _('Edit Table of Contents'))
        self.action_inline_toc = treg('chapters.png', _('&Insert inline Table of Contents'),
                                     self.boss.insert_inline_toc, 'insert-inline-toc', (), _('Insert inline Table of Contents'))
        self.action_fix_html_current = reg('html-fix.png', _('&Fix HTML'), partial(self.boss.fix_html, True), 'fix-html-current', (),
                                           _('Fix HTML in the current file'))
        self.action_fix_html_all = treg('html-fix.png', _('&Fix HTML - all files'), partial(self.boss.fix_html, False), 'fix-html-all', (),
                                       _('Fix HTML in all files'))
        self.action_pretty_current = reg('beautify.png', _('&Beautify current file'), partial(self.boss.pretty_print, True), 'pretty-current', (),
                                           _('Beautify current file'))
        self.action_pretty_all = treg('beautify.png', _('&Beautify all files'), partial(self.boss.pretty_print, False), 'pretty-all', (),
                                       _('Beautify all files'))
        self.action_insert_char = treg('character-set.png', _('&Insert special character'), self.boss.insert_character, 'insert-character', (),
                                      _('Insert special character'))
        self.action_rationalize_folders = treg('mimetypes/dir.png', _('&Arrange into folders'), self.boss.rationalize_folders, 'rationalize-folders', (),
                                      _('Arrange into folders'))
        self.action_set_semantics = treg('tags.png', _('Set &semantics'), self.boss.set_semantics, 'set-semantics', (),
                                        _('Set semantics'))
        self.action_filter_css = treg('filter.png', _('&Filter style information'), self.boss.filter_css, 'filter-css', (),
                                     _('Filter style information'))
        self.action_manage_fonts = treg('font.png', _('&Manage fonts'), self.boss.manage_fonts, 'manage-fonts', (), _('Manage fonts in the book'))
        self.action_add_cover = treg('default_cover.png', _('Add &cover'), self.boss.add_cover, 'add-cover', (), _('Add a cover to the book'))
        self.action_reports = treg(
            'reports.png', _('&Reports'), self.boss.show_reports, 'show-reports', ('Ctrl+Shift+R',), _('Show a report on various aspects of the book'))
        self.action_check_external_links = treg('insert-link.png', _('Check &external links'), self.boss.check_external_links, 'check-external-links', (), _(
            'Check external links in the book'))
        self.action_compress_images = treg('compress-image.png', _('C&ompress images losslessly'), self.boss.compress_images, 'compress-images', (), _(
            'Compress images losslessly'))
        self.action_transform_styles = treg('wizard.png', _('Transform &styles'), self.boss.transform_styles, 'transform-styles', (), _(
            'Transform styles used in the book'))
        self.action_transform_html = treg('wizard.png', _('Transform &HTML'), self.boss.transform_html, 'transform-html', (), _(
            'Transform HTML used in the book'))
        self.action_get_ext_resources = treg('download-metadata.png', _('Download external &resources'),
                                             self.boss.get_external_resources, 'get-external-resources', (), _(
            'Download external resources in the book (images/stylesheets/etc/ that are not included in the book)'))

        def ereg(icon, text, target, sid, keys, description):
            return reg(icon, text, partial(self.boss.editor_action, target), sid, keys, description)
        register_text_editor_actions(ereg, self.palette())

        # Polish actions
        group = _('Polish book')
        self.action_subset_fonts = treg(
            'subset-fonts.png', _('&Subset embedded fonts'), partial(
                self.boss.polish, 'subset', _('Subset fonts')), 'subset-fonts', (), _('Subset embedded fonts'))
        self.action_embed_fonts = treg(
            'embed-fonts.png', _('&Embed referenced fonts'), partial(
                self.boss.polish, 'embed', _('Embed fonts')), 'embed-fonts', (), _('Embed referenced fonts'))
        self.action_smarten_punctuation = treg(
            'smarten-punctuation.png', _('&Smarten punctuation (works best for English)'), partial(
                self.boss.polish, 'smarten_punctuation', _('Smarten punctuation')),
            'smarten-punctuation', (), _('Smarten punctuation'))
        self.action_remove_unused_css = treg(
            'edit-clear.png', _('Remove &unused CSS rules'), partial(
                self.boss.polish, 'remove_unused_css', _('Remove unused CSS rules')), 'remove-unused-css', (), _('Remove unused CSS rules'))
        self.action_upgrade_book_internals = treg(
            'arrow-up.png', _('&Upgrade book internals'), partial(
                self.boss.polish, 'upgrade_book', _('Upgrade book internals')), 'upgrade-book', (), _('Upgrade book internals'))

        # Preview actions
        group = _('Preview')
        self.action_auto_reload_preview = reg('auto-reload.png', _('Auto reload preview'), None, 'auto-reload-preview', (), _('Auto reload preview'))
        self.action_auto_sync_preview = reg('sync-right.png', _('Sync preview position to editor position'), None, 'sync-preview-to-editor', (), _(
            'Sync preview position to editor position'))
        self.action_reload_preview = reg('view-refresh.png', _('Refresh preview'), None, 'reload-preview', ('F5',), _('Refresh preview'))
        self.action_split_in_preview = reg('document-split.png', _('Split this file'), None, 'split-in-preview', (), _(
            'Split file in the preview panel'))
        self.action_find_next_preview = reg('arrow-down.png', _('Find next'), None, 'find-next-preview', (), _('Find next in preview'))
        self.action_find_prev_preview = reg('arrow-up.png', _('Find previous'), None, 'find-prev-preview', (), _('Find previous in preview'))

        # Search actions
        group = _('Search')
        self.action_find = treg('search.png', _('&Find/replace'), self.boss.show_find, 'find-replace', ('Ctrl+F',), _('Show the Find/replace panel'))

        def sreg(name, text, action, overrides={}, keys=(), description=None, icon=None):
            return reg(icon, text, partial(self.boss.search_action_triggered, action, overrides), name, keys, description or text.replace('&', ''))
        self.action_find_next = sreg('find-next', _('Find &next'),
                                     'find', {'direction':'down'}, ('F3', 'Ctrl+G'), _('Find next match'))
        self.action_find_previous = sreg('find-previous', _('Find &previous'),
                                         'find', {'direction':'up'}, ('Shift+F3', 'Shift+Ctrl+G'), _('Find previous match'))
        self.action_replace = sreg('replace', _('&Replace'),
                                   'replace', keys=('Ctrl+R'), description=_('Replace current match'))
        self.action_replace_next = sreg('replace-next', _('Replace and find ne&xt'),
                                        'replace-find', {'direction':'down'}, ('Ctrl+]'), _('Replace current match and find next'))
        self.action_replace_previous = sreg('replace-previous', _('R&eplace and find previous'),
                                        'replace-find', {'direction':'up'}, ('Ctrl+['), _('Replace current match and find previous'))
        self.action_replace_all = sreg('replace-all', _('Replace &all'),
                                   'replace-all', keys=('Ctrl+A'), description=_('Replace all matches'))
        self.action_count = sreg('count-matches', _('&Count all'),
                                   'count', keys=('Ctrl+N'), description=_('Count number of matches'))
        self.action_mark = reg(None, _('&Mark selected text'), self.boss.mark_selected_text, 'mark-selected-text', ('Ctrl+Shift+M',),
                               _('Mark selected text or unmark already marked text'))
        self.action_mark.default_text = self.action_mark.text()
        self.action_go_to_line = reg(None, _('Go to &line'), self.boss.go_to_line_number, 'go-to-line-number', ('Ctrl+.',), _('Go to line number'))
        self.action_saved_searches = treg('folder_saved_search.png', _('Sa&ved searches'),
                                          self.boss.saved_searches, 'saved-searches', (), _('Show the saved searches dialog'))
        self.action_text_search = treg('view.png', _('&Search ignoring HTML markup'),
                                          self.boss.show_text_search, 'text-search', (), _('Show the text search panel'))

        # Check Book actions
        group = _('Check book')
        self.action_check_book = treg('debug.png', _('C&heck book'), self.boss.check_requested, 'check-book', ('F7'), _('Check book for errors'))
        self.action_spell_check_book = treg('spell-check.png', _('Check &spelling'), self.boss.spell_check_requested, 'spell-check-book', ('Alt+F7'), _(
            'Check book for spelling errors'))
        self.action_check_book_next = reg('forward.png', _('&Next error'), partial(
            self.check_book.next_error, delta=1), 'check-book-next', ('Ctrl+F7'), _('Show next error'))
        self.action_check_book_previous = reg('back.png', _('&Previous error'), partial(
            self.check_book.next_error, delta=-1), 'check-book-previous', ('Ctrl+Shift+F7'), _('Show previous error'))
        self.action_spell_check_next = reg('forward.png', _('&Next spelling mistake'),
            self.boss.next_spell_error, 'spell-next', ('F8'), _('Go to next spelling mistake'))

        # Miscellaneous actions
        group = pgettext('edit book actions', 'Miscellaneous')
        self.action_create_checkpoint = treg(
            'marked.png', _('&Create checkpoint'), self.boss.create_checkpoint, 'create-checkpoint', (), _(
                'Create a checkpoint with the current state of the book'))
        self.action_close_current_tab = reg(
            'window-close.png', _('&Close current tab'), self.central.close_current_editor, 'close-current-tab', 'Ctrl+W', _(
                'Close the currently open tab'))
        self.action_close_all_but_current_tab = reg(
            'edit-clear.png', _('C&lose other tabs'), self.central.close_all_but_current_editor, 'close-all-but-current-tab', 'Ctrl+Alt+W', _(
                'Close all tabs except the current tab'))
        self.action_close_to_right = reg(
            'edit-clear.png', _('Close tabs to the &right'), self.central.close_to_right_of_current_editor, 'close-tabs-to-right-of', 'Ctrl+Shift+W', _(
                'Close tabs to the right of the current tab'))
        self.action_help = treg(
            'help.png', _('User &Manual'), lambda : open_url(QUrl(localize_user_manual_link(
                'https://manual.calibre-ebook.com/edit.html'))), 'user-manual', 'F1', _(
                'Show User Manual'))
        self.action_browse_images = treg(
            'view-image.png', _('&Browse images in book'), self.boss.browse_images, 'browse-images', (), _(
                'Browse images in the books visually'))
        self.action_multiple_split = treg(
            'document-split.png', _('&Split at multiple locations'), self.boss.multisplit, 'multisplit', (), _(
                'Split HTML file at multiple locations'))
        self.action_compare_book = treg('diff.png', _('Compare to &another book'), self.boss.compare_book, 'compare-book', (), _(
            'Compare to another book'))
        self.action_manage_snippets = treg(
            'snippets.png', _('Manage &Snippets'), self.boss.manage_snippets, 'manage-snippets', (), _(
                'Manage user created Snippets'))

        self.plugin_menu_actions = []

        create_plugin_actions(actions, toolbar_actions, self.plugin_menu_actions)

    def create_menubar(self):
        if ismacos:
            p, q = self.create_application_menubar()
            q.triggered.connect(self.action_quit.trigger)
            p.triggered.connect(self.action_preferences.trigger)
        b = QMenuBar(self)
        self.setMenuBar(b)
        b.is_native_menubar = False

        f = b.addMenu(_('&File'))
        f.addAction(self.action_new_file)
        f.addAction(self.action_import_files)
        f.addSeparator()
        f.addAction(self.action_open_book)
        f.addAction(self.action_new_book)
        f.addAction(self.action_import_book)
        f.addAction(self.action_open_book_folder)
        self.recent_books_menu = f.addMenu(_('&Recently opened books'))
        self.update_recent_books()
        f.addSeparator()
        f.addAction(self.action_save)
        f.addAction(self.action_save_copy)
        f.addSeparator()
        f.addAction(self.action_compare_book)
        f.addAction(self.action_quit)

        e = b.addMenu(_('&Edit'))
        e.addAction(self.action_global_undo)
        e.addAction(self.action_global_redo)
        e.addAction(self.action_create_checkpoint)
        e.addSeparator()
        e.addAction(self.action_editor_undo)
        e.addAction(self.action_editor_redo)
        e.addSeparator()
        e.addAction(self.action_editor_cut)
        e.addAction(self.action_editor_copy)
        e.addAction(self.action_editor_paste)
        e.addAction(self.action_insert_char)
        e.addSeparator()
        e.addAction(self.action_quick_edit)
        e.addAction(self.action_preferences)

        e = b.addMenu(_('&Tools'))
        tm = e.addMenu(_('Table of Contents'))
        tm.addAction(self.action_toc)
        tm.addAction(self.action_inline_toc)
        e.addAction(self.action_manage_fonts)
        e.addAction(self.action_embed_fonts)
        e.addAction(self.action_subset_fonts)
        e.addAction(self.action_compress_images)
        e.addAction(self.action_smarten_punctuation)
        e.addAction(self.action_remove_unused_css)
        e.addAction(self.action_transform_styles)
        e.addAction(self.action_transform_html)
        e.addAction(self.action_fix_html_all)
        e.addAction(self.action_pretty_all)
        e.addAction(self.action_rationalize_folders)
        e.addAction(self.action_add_cover)
        e.addAction(self.action_set_semantics)
        e.addAction(self.action_filter_css)
        e.addAction(self.action_spell_check_book)
        er = e.addMenu(_('External &links'))
        er.addAction(self.action_check_external_links)
        er.addAction(self.action_get_ext_resources)
        e.addAction(self.action_check_book)
        e.addAction(self.action_reports)
        e.addAction(self.action_upgrade_book_internals)

        e = b.addMenu(_('&View'))
        t = e.addMenu(_('Tool&bars'))
        e.addSeparator()
        for name in sorted(actions, key=lambda x:sort_key(actions[x].text())):
            ac = actions[name]
            if name.endswith('-dock'):
                e.addAction(ac)
            elif name.endswith('-bar'):
                t.addAction(ac)
        e.addAction(self.action_browse_images)
        e.addSeparator()
        e.addAction(self.action_close_current_tab)
        e.addAction(self.action_close_all_but_current_tab)

        e = b.addMenu(_('&Search'))
        a = e.addAction
        a(self.action_find)
        e.addSeparator()
        a(self.action_find_next)
        a(self.action_find_previous)
        e.addSeparator()
        a(self.action_replace)
        a(self.action_replace_next)
        a(self.action_replace_previous)
        a(self.action_replace_all)
        e.addSeparator()
        a(self.action_count)
        e.addSeparator()
        a(self.action_mark)
        e.addSeparator()
        a(self.action_go_to_line)
        e.addSeparator()
        a(self.action_saved_searches)
        e.aboutToShow.connect(self.search_menu_about_to_show)
        e.addSeparator()
        a(self.action_text_search)

        if self.plugin_menu_actions:
            e = b.addMenu(_('&Plugins'))
            for ac in sorted(self.plugin_menu_actions, key=lambda x:sort_key(str(x.text()))):
                e.addAction(ac)

        e = b.addMenu(_('&Help'))
        a = e.addAction
        a(self.action_help)
        a(QIcon(I('donate.png')), _('&Donate to support calibre development'), open_donate)
        a(self.action_preferences)

    def search_menu_about_to_show(self):
        ed = self.central.current_editor
        update_mark_text_action(ed)

    def update_recent_books(self):
        m = self.recent_books_menu
        m.clear()
        books = tprefs.get('recent-books', [])
        for path in books:
            m.addAction(self.elided_text(path, width=500), partial(self.boss.open_book, path=path))

    def create_toolbars(self):
        def create(text, name):
            name += '-bar'
            b = self.addToolBar(text)
            b.setObjectName(name)  # Needed for saveState
            actions[name] = b.toggleViewAction()
            b.setIconSize(QSize(tprefs['toolbar_icon_size'], tprefs['toolbar_icon_size']))
            return b
        self.global_bar = create(_('Book tool bar'), 'global')
        self.tools_bar = create(_('Tools tool bar'), 'tools')
        self.plugins_bar = create(_('Plugins tool bar'), 'plugins')
        self.populate_toolbars(animate=True)

    def populate_toolbars(self, animate=False):
        self.global_bar.clear(), self.tools_bar.clear(), self.plugins_bar.clear()

        def add(bar, ac):
            if ac is None:
                bar.addSeparator()
            elif ac == 'donate':
                self.donate_button = b = ThrobbingButton(self)
                b.clicked.connect(open_donate)
                b.setAutoRaise(True)
                b.setToolTip(_('Donate to support calibre development'))
                if animate:
                    QTimer.singleShot(10, b.start_animation)
                bar.addWidget(b)
            else:
                try:
                    bar.addAction(actions[ac])
                except KeyError:
                    if DEBUG:
                        prints(f'Unknown action for toolbar {str(bar.objectName())!r}: {ac!r}')

        for x in tprefs['global_book_toolbar']:
            add(self.global_bar, x)

        for x in tprefs['global_tools_toolbar']:
            add(self.tools_bar, x)

        for x in tprefs['global_plugins_toolbar']:
            add(self.plugins_bar, x)
        self.plugins_bar.setVisible(bool(tprefs['global_plugins_toolbar']))

    def create_docks(self):

        def create(name, oname):
            oname += '-dock'
            d = QDockWidget(name, self)
            d.setObjectName(oname)  # Needed for saveState
            ac = d.toggleViewAction()
            desc = _('Toggle %s') % name.replace('&', '')
            self.keyboard.register_shortcut(
                oname, desc, description=desc, action=ac, group=_('Windows'))
            actions[oname] = ac
            setattr(self, oname.replace('-', '_'), d)
            return d

        d = create(_('File browser'), 'files-browser')
        d.setAllowedAreas(Qt.DockWidgetArea.LeftDockWidgetArea | Qt.DockWidgetArea.RightDockWidgetArea)
        self.file_list = FileListWidget(d)
        d.setWidget(self.file_list)
        self.addDockWidget(Qt.DockWidgetArea.LeftDockWidgetArea, d)

        d = create(_('File preview'), 'preview')
        d.setAllowedAreas(Qt.DockWidgetArea.LeftDockWidgetArea | Qt.DockWidgetArea.RightDockWidgetArea)
        self.preview = Preview(d)
        d.setWidget(self.preview)
        self.addDockWidget(Qt.DockWidgetArea.RightDockWidgetArea, d)

        d = create(_('Live CSS'), 'live-css')
        d.setAllowedAreas(
            Qt.DockWidgetArea.LeftDockWidgetArea | Qt.DockWidgetArea.RightDockWidgetArea |
            Qt.DockWidgetArea.BottomDockWidgetArea | Qt.DockWidgetArea.TopDockWidgetArea)
        self.live_css = LiveCSS(self.preview, parent=d)
        d.setWidget(self.live_css)
        self.addDockWidget(Qt.DockWidgetArea.RightDockWidgetArea, d)
        d.close()  # Hidden by default

        d = create(_('Check book'), 'check-book')
        d.setAllowedAreas(
            Qt.DockWidgetArea.LeftDockWidgetArea | Qt.DockWidgetArea.RightDockWidgetArea |
            Qt.DockWidgetArea.BottomDockWidgetArea | Qt.DockWidgetArea.TopDockWidgetArea)
        d.setWidget(self.check_book)
        self.addDockWidget(Qt.DockWidgetArea.TopDockWidgetArea, d)
        d.close()  # By default the check window is closed

        d = create(_('Inspector'), 'inspector')
        d.setAllowedAreas(
            Qt.DockWidgetArea.LeftDockWidgetArea | Qt.DockWidgetArea.RightDockWidgetArea |
            Qt.DockWidgetArea.BottomDockWidgetArea | Qt.DockWidgetArea.TopDockWidgetArea)
        d.setWidget(self.preview.inspector)
        self.preview.inspector.setParent(d)
        self.addDockWidget(Qt.DockWidgetArea.BottomDockWidgetArea, d)
        d.close()  # By default the inspector window is closed
        QTimer.singleShot(10, self.preview.inspector.connect_to_dock)

        d = create(_('Table of Contents'), 'toc-viewer')
        d.setAllowedAreas(
            Qt.DockWidgetArea.LeftDockWidgetArea | Qt.DockWidgetArea.RightDockWidgetArea |
            Qt.DockWidgetArea.BottomDockWidgetArea | Qt.DockWidgetArea.TopDockWidgetArea)
        d.setWidget(self.toc_view)
        self.addDockWidget(Qt.DockWidgetArea.LeftDockWidgetArea, d)
        d.close()  # Hidden by default

        d = create(_('Text search'), 'text-search')
        d.setAllowedAreas(
            Qt.DockWidgetArea.LeftDockWidgetArea | Qt.DockWidgetArea.RightDockWidgetArea |
            Qt.DockWidgetArea.BottomDockWidgetArea | Qt.DockWidgetArea.TopDockWidgetArea)
        d.setWidget(self.text_search)
        self.addDockWidget(Qt.DockWidgetArea.LeftDockWidgetArea, d)
        d.close()  # Hidden by default

        d = create(_('Checkpoints'), 'checkpoints')
        d.setAllowedAreas(
            Qt.DockWidgetArea.LeftDockWidgetArea | Qt.DockWidgetArea.RightDockWidgetArea |
            Qt.DockWidgetArea.BottomDockWidgetArea | Qt.DockWidgetArea.TopDockWidgetArea)
        self.checkpoints = CheckpointView(self.boss.global_undo, parent=d)
        d.setWidget(self.checkpoints)
        self.addDockWidget(Qt.DockWidgetArea.LeftDockWidgetArea, d)
        d.close()  # Hidden by default

        d = create(_('Saved searches'), 'saved-searches')
        d.setAllowedAreas(
            Qt.DockWidgetArea.LeftDockWidgetArea | Qt.DockWidgetArea.RightDockWidgetArea |
            Qt.DockWidgetArea.BottomDockWidgetArea | Qt.DockWidgetArea.TopDockWidgetArea)
        d.setWidget(self.saved_searches)
        self.addDockWidget(Qt.DockWidgetArea.LeftDockWidgetArea, d)
        d.close()  # Hidden by default

    def resizeEvent(self, ev):
        self.blocking_job.resize(ev.size())
        return super().resizeEvent(ev)

    def update_window_title(self):
        cc = current_container()
        if cc is not None:
            fname = os.path.basename(cc.path_to_ebook)
            self.setWindowTitle(self.current_metadata.title + ' [%s] :: %s :: %s' %(cc.book_type_for_display, fname, self.APP_NAME))
        else:
            self.setWindowTitle(self.APP_NAME)

    def closeEvent(self, e):
        if self.boss.quit():
            e.accept()
        else:
            e.ignore()

    def save_state(self):
        tprefs.set('main_window_geometry', bytearray(self.saveGeometry()))
        tprefs.set('main_window_state', bytearray(self.saveState(self.STATE_VERSION)))
        self.central.save_state()
        self.saved_searches.save_state()
        self.check_book.save_state()
        self.text_search.save_state()

    def restore_state(self):
        geom = tprefs.get('main_window_geometry', None)
        if geom is not None:
            QApplication.instance().safe_restore_geometry(self, geom)
        state = tprefs.get('main_window_state', None)
        if state is not None:
            self.restoreState(state, self.STATE_VERSION)
        self.central.restore_state()
        self.saved_searches.restore_state()

    def contextMenuEvent(self, ev):
        ev.ignore()