#!/usr/bin/env python


__license__   = 'GPL v3'
__copyright__ = '2009, Kovid Goyal <kovid@kovidgoyal.net>'
__docformat__ = 'restructuredtext en'

import re
import time
from functools import partial

from qt.core import QAction, QApplication, QComboBox, QCompleter, QDialog, QEvent, QIcon, QKeyEvent, QKeySequence, QLineEdit, Qt, QTimer, pyqtSignal, pyqtSlot

from calibre.gui2 import QT_HIDDEN_CLEAR_ACTION, config, gprefs, question_dialog
from calibre.gui2.dialogs.saved_search_editor import SavedSearchEditor
from calibre.gui2.dialogs.search import SearchDialog
from calibre.gui2.widgets import stylesheet_for_lineedit
from calibre.utils.icu import primary_sort_key
from calibre.utils.localization import pgettext


class AsYouType(str):

    def __new__(cls, text):
        self = str.__new__(cls, text)
        self.as_you_type = True
        return self


class SearchLineEdit(QLineEdit):  # {{{
    key_pressed = pyqtSignal(object)
    clear_history = pyqtSignal()
    select_on_mouse_press = None
    as_url = None

    def keyPressEvent(self, event):
        self.key_pressed.emit(event)
        QLineEdit.keyPressEvent(self, event)

    def dropEvent(self, ev):
        self.parent().normalize_state()
        return QLineEdit.dropEvent(self, ev)

    def contextMenuEvent(self, ev):
        self.parent().normalize_state()
        menu = self.createStandardContextMenu()
        menu.setAttribute(Qt.WidgetAttribute.WA_DeleteOnClose)
        ac = menu.addAction(_('Paste and &search'))
        ac.setEnabled(bool(QApplication.clipboard().text()))
        ac.setIcon(QIcon.ic('search.png'))
        ac.triggered.connect(self.paste_and_search)
        for action in menu.actions():
            if action.text().startswith(_('&Paste') + '\t'):
                menu.insertAction(action, ac)
                break
        else:
            menu.addAction(ac)
        menu.addSeparator()
        ac = menu.addAction(_('Invert current search'))
        ac.setEnabled(bool(self.text().strip()))
        ac.setIcon(QIcon.ic('search.png'))
        ac.triggered.connect(self.invert_search)
        menu.addAction(ac)
        menu.addSeparator()
        if self.as_url is not None:
            url = self.as_url(self.text())
            if url:
                menu.addAction(_('Copy search as URL'), lambda: QApplication.clipboard().setText(url))
        menu.addAction(_('&Clear search history')).triggered.connect(self.clear_history)
        menu.exec(ev.globalPos())

    def invert_search(self):
        q = self.text().strip()
        if q:
            if q.startswith('NOT ( ') and q.endswith(' )'):
                q = q[6:-2]
            else:
                q = f'NOT ( {q} )'
            self.setText(q)
            ev = QKeyEvent(QEvent.Type.KeyPress, Qt.Key.Key_Enter, Qt.KeyboardModifier.NoModifier)
            self.keyPressEvent(ev)

    def paste_and_search(self):
        self.paste()
        ev = QKeyEvent(QEvent.Type.KeyPress, Qt.Key.Key_Enter, Qt.KeyboardModifier.NoModifier)
        self.keyPressEvent(ev)

    @pyqtSlot()
    def paste(self, *args):
        self.parent().normalize_state()
        return QLineEdit.paste(self)

    def focusInEvent(self, ev):
        self.select_on_mouse_press = time.time()
        return QLineEdit.focusInEvent(self, ev)

    def mousePressEvent(self, ev):
        QLineEdit.mousePressEvent(self, ev)
        if self.select_on_mouse_press is not None and abs(time.time() - self.select_on_mouse_press) < 0.2:
            self.selectAll()
        self.select_on_mouse_press = None
# }}}


class SearchBox2(QComboBox):  # {{{

    '''
    To use this class:

        * Call initialize()
        * Connect to the search() and cleared() signals from this widget.
        * Connect to the changed() signal to know when the box content changes
        * Connect to focus_to_library() signal to be told to manually change focus
        * Call search_done() after every search is complete
        * Call set_search_string() to perform a search programmatically
        * You can use the current_text property to get the current search text
          Be aware that if you are using it in a slot connected to the
          changed() signal, if the connection is not queued it will not be
          accurate.
    '''

    INTERVAL = 1500  #: Time to wait before emitting search signal
    MAX_COUNT = 25

    search  = pyqtSignal(object)
    cleared = pyqtSignal()
    changed = pyqtSignal()
    focus_to_library = pyqtSignal()

    def __init__(self, parent=None, add_clear_action=True, as_url=None):
        QComboBox.__init__(self, parent)
        self.line_edit = SearchLineEdit(self)
        self.line_edit.as_url = as_url
        self.setLineEdit(self.line_edit)
        self.line_edit.clear_history.connect(self.clear_history)
        if add_clear_action:
            self.lineEdit().setClearButtonEnabled(True)
            ac = self.findChild(QAction, QT_HIDDEN_CLEAR_ACTION)
            if ac is not None:
                ac.triggered.connect(self.clear_clicked)

        c = self.line_edit.completer()
        c.setCompletionMode(QCompleter.CompletionMode.PopupCompletion)
        c.highlighted[str].connect(self.completer_used)

        self.line_edit.key_pressed.connect(self.key_pressed, type=Qt.ConnectionType.DirectConnection)
        # QueuedConnection as workaround for https://bugreports.qt-project.org/browse/QTBUG-40807
        self.textActivated.connect(self.history_selected, type=Qt.ConnectionType.QueuedConnection)
        self.setEditable(True)
        self.as_you_type = True
        self.timer = QTimer()
        self.timer.setSingleShot(True)
        self.timer.timeout.connect(self.timer_event, type=Qt.ConnectionType.QueuedConnection)
        self.setInsertPolicy(QComboBox.InsertPolicy.NoInsert)
        self.setMaxCount(self.MAX_COUNT)
        self.setSizeAdjustPolicy(QComboBox.SizeAdjustPolicy.AdjustToMinimumContentsLengthWithIcon)
        self.setMinimumContentsLength(25)
        self._in_a_search = False
        self.tool_tip_text = self.toolTip()
        self.parse_error_action = None

    def add_action(self, icon, position=QLineEdit.ActionPosition.TrailingPosition):
        if not isinstance(icon, QIcon):
            icon = QIcon.ic(icon)
        return self.lineEdit().addAction(icon, position)

    def initialize(self, opt_name, colorize=False, help_text=_('Search'), as_you_type=None):
        self.as_you_type = config['search_as_you_type'] if as_you_type is None else as_you_type
        self.opt_name = opt_name
        items = []
        for item in config[opt_name]:
            if item not in items:
                items.append(item)
        self.addItems(items)
        self.line_edit.setPlaceholderText(help_text)
        self.clear()

    def clear_history(self):
        config[self.opt_name] = []
        super().clear()
        self.clear()
    clear_search_history = clear_history

    def hide_completer_popup(self):
        try:
            self.lineEdit().completer().popup().setVisible(False)
        except Exception:
            pass

    def normalize_state(self):
        self.setToolTip(self.tool_tip_text)
        self.setStyleSheet('')
        self.show_parse_error_action(False)

    def text(self):
        return self.currentText()

    def clear(self, emit_search=True):
        self.show_parse_error_action(False)
        self.normalize_state()
        self.setEditText('')
        if emit_search:
            self.search.emit('')
        self._in_a_search = False
        self.cleared.emit()

    def clear_clicked(self, *args):
        self.clear()
        self.setFocus(Qt.FocusReason.OtherFocusReason)

    def show_parse_error_action(self, to_show, tooltip=''):
        if self.parse_error_action is not None:
            self.parse_error_action.setVisible(to_show)
            self.parse_error_action.setToolTip(tooltip)

    def search_done(self, ok):
        if isinstance(ok, (str, bytes)):
            self.setToolTip(ok)
            self.show_parse_error_action(True, tooltip=ok)
            ok = False
        if not str(self.currentText()).strip():
            self.setStyleSheet('')
            self.clear(emit_search=False)
            return
        self._in_a_search = ok
        if self.parse_error_action is not None and not ok:
            self.setStyleSheet(stylesheet_for_lineedit(bool(ok), 'QComboBox'))
        else:
            self.setStyleSheet('')

    # Comes from the lineEdit control
    def key_pressed(self, event):
        k = event.key()
        if k in (Qt.Key.Key_Left, Qt.Key.Key_Right, Qt.Key.Key_Up, Qt.Key.Key_Down,
                Qt.Key.Key_Home, Qt.Key.Key_End, Qt.Key.Key_PageUp, Qt.Key.Key_PageDown,
                Qt.Key.Key_unknown):
            return
        self.normalize_state()
        if self._in_a_search:
            self.changed.emit()
            self._in_a_search = False
        if event.key() in (Qt.Key.Key_Return, Qt.Key.Key_Enter):
            self.do_search()
            self.focus_to_library.emit()
        elif self.as_you_type and str(event.text()):
            self.timer.start(1500)

    # Comes from the combobox itself
    def keyPressEvent(self, event):
        self.show_parse_error_action(False)
        k = event.key()
        if k in (Qt.Key.Key_Enter, Qt.Key.Key_Return):
            return self.do_search()
        if k not in (Qt.Key.Key_Up, Qt.Key.Key_Down):
            return QComboBox.keyPressEvent(self, event)
        self.blockSignals(True)
        self.normalize_state()
        if k == Qt.Key.Key_Down and self.currentIndex() == 0 and not self.lineEdit().text():
            self.setCurrentIndex(1), self.setCurrentIndex(0)
            event.accept()
        else:
            QComboBox.keyPressEvent(self, event)
        self.blockSignals(False)

    def completer_used(self, text):
        self.timer.stop()
        self.normalize_state()

    def timer_event(self):
        self._do_search(as_you_type=True)
        # since this is an automatic search keep focus
        self.setFocus(Qt.FocusReason.OtherFocusReason)

    def history_selected(self, text):
        self.changed.emit()
        self.do_search()

    def _do_search(self, store_in_history=True, as_you_type=False):
        self.hide_completer_popup()
        text = str(self.currentText()).strip()
        if not text:
            return self.clear()
        if as_you_type:
            text = AsYouType(text)
        self.search.emit(text)

        if store_in_history:
            idx = self.findText(text, Qt.MatchFlag.MatchFixedString|Qt.MatchFlag.MatchCaseSensitive)
            self.block_signals(True)
            if idx < 0:
                self.insertItem(0, text)
            else:
                t = self.itemText(idx)
                self.removeItem(idx)
                self.insertItem(0, t)
            self.setCurrentIndex(0)
            self.block_signals(False)
            history = [str(self.itemText(i)) for i in
                    range(self.count())]
            config[self.opt_name] = history

    def do_search(self, *args):
        self._do_search()
        self.timer.stop()

    def block_signals(self, yes):
        self.blockSignals(yes)
        self.line_edit.blockSignals(yes)

    def set_search_string(self, txt, store_in_history=False, emit_changed=True):
        if not store_in_history:
            self.textActivated.disconnect()
        try:
            self.setFocus(Qt.FocusReason.OtherFocusReason)
            if not txt:
                self.clear()
            else:
                self.normalize_state()
                # must turn on case sensitivity here so that tag browser strings
                # are not case-insensitively replaced from history
                self.line_edit.completer().setCaseSensitivity(Qt.CaseSensitivity.CaseSensitive)
                self.setEditText(txt)
                self.line_edit.end(False)
                if emit_changed:
                    self.changed.emit()
                self._do_search(store_in_history=store_in_history)
                self.line_edit.completer().setCaseSensitivity(Qt.CaseSensitivity.CaseInsensitive)
            self.focus_to_library.emit()
        finally:
            if not store_in_history:
                # QueuedConnection as workaround for https://bugreports.qt-project.org/browse/QTBUG-40807
                self.textActivated.connect(self.history_selected, type=Qt.ConnectionType.QueuedConnection)

    def search_as_you_type(self, enabled):
        self.as_you_type = enabled

    def in_a_search(self):
        return self._in_a_search

    @property
    def current_text(self):
        return str(self.lineEdit().text())

    # }}}


class SearchBoxMixin:  # {{{

    def __init__(self, *args, **kwargs):
        pass

    def init_search_box_mixin(self):
        self.search.initialize('main_search_history',
                help_text=_('Search (For advanced search click the gear icon to the left)'))
        self.search.cleared.connect(self.search_box_cleared)
        # Queued so that search.current_text will be correct
        self.search.changed.connect(self.search_box_changed,
                type=Qt.ConnectionType.QueuedConnection)
        self.search.focus_to_library.connect(self.focus_to_library)
        self.advanced_search_toggle_action.triggered.connect(self.do_advanced_search)

        self.search.clear()
        self.search.setMaximumWidth(self.width()-150)
        self.action_focus_search = QAction(self)
        shortcuts = [str(x.toString(QKeySequence.SequenceFormat.PortableText)) for x in QKeySequence.keyBindings(QKeySequence.StandardKey.Find)]
        shortcuts += ['/', 'Alt+S']
        self.keyboard.register_shortcut('start search', _('Start search'),
                default_keys=shortcuts, action=self.action_focus_search)
        self.action_focus_search.triggered.connect(self.focus_search_box)
        self.addAction(self.action_focus_search)
        self.search.setStatusTip(re.sub(r'<\w+>', ' ',
            str(self.search.toolTip())))
        self.set_highlight_only_button_icon()
        self.highlight_only_button.clicked.connect(self.highlight_only_clicked)
        tt = _('Enable or disable search highlighting.') + '<br><br>'
        tt += config.help('highlight_search_matches')
        self.highlight_only_button.setToolTip(tt)
        self.highlight_only_action = ac = QAction(self)
        self.addAction(ac), ac.triggered.connect(self.highlight_only_clicked)
        self.keyboard.register_shortcut('highlight search results', _('Highlight search results'), action=self.highlight_only_action)
        self.refresh_search_bar_widgets()

    def refresh_search_bar_widgets(self):
        self.set_highlight_only_button_icon()
        if gprefs['search_tool_bar_shows_text']:
            self.search_bar.search_button.setText(_('Search'))
            self.search_bar.search_button.setToolButtonStyle(Qt.ToolButtonStyle.ToolButtonTextBesideIcon)
        else:
            self.search_bar.search_button.setText(None)
            self.search_bar.search_button.setToolButtonStyle(Qt.ToolButtonStyle.ToolButtonIconOnly)

    def highlight_only_clicked(self, state):
        if not config['highlight_search_matches'] and not question_dialog(self, _('Are you sure?'),
            _('This will change how searching works. When you search, instead of showing only the '
                'matching books, all books will be shown with the matching books highlighted. '
                'Are you sure this is what you want?'), skip_dialog_name='confirm_search_highlight_toggle'):
            return
        config['highlight_search_matches'] = not config['highlight_search_matches']
        self.set_highlight_only_button_icon()
        self.search.do_search()
        self.focus_to_library()

    def set_highlight_only_button_icon(self):
        b = self.highlight_only_button
        if config['highlight_search_matches']:
            b.setIcon(QIcon.ic('highlight_only_on.png'))
            if gprefs['search_tool_bar_shows_text']:
                b.setText(_('Filter'))
                b.setToolButtonStyle(Qt.ToolButtonStyle.ToolButtonTextBesideIcon)
            else:
                b.setText(None)
                b.setToolButtonStyle(Qt.ToolButtonStyle.ToolButtonIconOnly)
        else:
            b.setIcon(QIcon.ic('highlight_only_off.png'))
            if gprefs['search_tool_bar_shows_text']:
                b.setText(pgettext('mark books matching search result instead of filtering them', 'Highlight'))
                b.setToolButtonStyle(Qt.ToolButtonStyle.ToolButtonTextBesideIcon)
            else:
                b.setText(None)
                b.setToolButtonStyle(Qt.ToolButtonStyle.ToolButtonIconOnly)
        self.highlight_only_button.setVisible(gprefs['show_highlight_toggle_button'])
        self.library_view.model().set_highlight_only(config['highlight_search_matches'])

    def focus_search_box(self, *args):
        self.search.setFocus(Qt.FocusReason.OtherFocusReason)
        self.search.lineEdit().selectAll()

    def search_box_cleared(self):
        self.tags_view.clear()
        self.set_number_of_books_shown()

    def search_box_changed(self):
        self.tags_view.conditional_clear(self.search.current_text)

    def do_advanced_search(self, *args):
        d = SearchDialog(self, self.library_view.model().db)
        if d.exec() == QDialog.DialogCode.Accepted:
            self.search.set_search_string(d.search_string(), store_in_history=True)

    def do_search_button(self):
        self.search.do_search()
        self.focus_to_library()

    def focus_to_library(self):
        self.current_view().setFocus(Qt.FocusReason.OtherFocusReason)

    # }}}


class SavedSearchBoxMixin:  # {{{

    def __init__(self, *args, **kwargs):
        pass

    def init_saved_seach_box_mixin(self):
        pass

    def add_saved_searches_to_menu(self, menu, db, add_action_func=None):
        def add_action(current_menu, whole_name, last_component, func=None):
            if add_action_func is None:
                return current_menu.addAction(last_component, func)
            return add_action_func(current_menu, whole_name, last_component)

        folder_icon = QIcon.ic('folder_saved_search.png')
        search_icon = QIcon.ic('search.png')
        use_hierarchy = 'search' in db.new_api.pref('categories_using_hierarchy', [])
        submenus = {}
        for name in sorted(db.saved_search_names(), key=lambda x: primary_sort_key(x.strip())):
            display_name = name.replace('&', '&&')
            current_menu = menu
            if use_hierarchy:
                components = tuple(n.strip() for n in name.split('.'))
                hierarchy = components[:-1]
                last = components[-1]
                # Walk the hierarchy, creating submenus as needed
                for i,c in enumerate(hierarchy, start=1):
                    hierarchical_prefix = '.'.join(hierarchy[:i])
                    if hierarchical_prefix not in submenus:
                        current_menu = current_menu.addMenu(c.replace('&', '&&'))
                        current_menu.setIcon(folder_icon)
                        submenus[hierarchical_prefix] = current_menu
                    else:
                        current_menu = submenus[hierarchical_prefix]
                ac = add_action(current_menu, display_name, last.replace('&', '&&'),
                                partial(self.search.set_search_string, 'search:"='+name+'"'))
            else:
                ac = add_action(current_menu, display_name, display_name,
                                partial(self.search.set_search_string, 'search:"='+name+'"'))
            if ac.icon().isNull():
                ac.setIcon(search_icon)

    def populate_add_saved_search_menu(self, to_menu):
        m = to_menu
        m.clear()
        m.addAction(QIcon.ic('search_add_saved.png'), _('Add Saved search'), self.add_saved_search)
        m.addAction(QIcon.ic('search_copy_saved.png'), _('Get Saved search expression'),
                     self.get_saved_search_text)
        m.addAction(QIcon.ic('folder_saved_search.png'), _('Manage Saved searches'),
                     partial(self.do_saved_search_edit, None))
        m.addSeparator()
        self.add_saved_searches_to_menu(m, self.current_db)

    def saved_searches_changed(self, set_restriction=None, recount=True):
        self.build_search_restriction_list()
        if recount:
            self.tags_view.recount()
        if set_restriction:  # redo the search restriction if there was one
            self.apply_named_search_restriction(set_restriction)

    def do_saved_search_edit(self, search):
        d = SavedSearchEditor(self, search)
        d.exec()
        if d.result() == QDialog.DialogCode.Accepted:
            self.do_rebuild_saved_searches()

    def do_rebuild_saved_searches(self):
        self.saved_searches_changed()

    def add_saved_search(self):
        from calibre.gui2.dialogs.saved_search_editor import AddSavedSearch
        d = AddSavedSearch(parent=self, search=self.search.current_text)
        if d.exec() == QDialog.DialogCode.Accepted:
            self.current_db.new_api.ensure_has_search_category(fail_on_existing=False)
            self.do_rebuild_saved_searches()

    def get_saved_search_text(self, search_name=None):
        db = self.current_db
        try:
            current_search = search_name if search_name else self.search.currentText()
            if not current_search.startswith('search:'):
                raise ValueError()
            # This strange expression accounts for the four ways a search can be written:
            # search:fff, search:"fff", search:"=fff". and search:="fff"
            current_search = current_search[7:].lstrip('=').strip('"').lstrip('=')
            current_search = db.saved_search_lookup(current_search)
            if not current_search:
                raise ValueError()
            self.search.set_search_string(current_search)
        except Exception:
            from calibre.gui2.ui import get_gui
            get_gui().status_bar.show_message(_('Current search is not a saved search'), 3000)
    # }}}
