dupeguru/qtlib/recent.py

# Created By: Virgil Dupras
# Created On: 2009-11-12
# Copyright 2014 Hardcoded Software (http://www.hardcoded.net)
# 
# This software is licensed under the "BSD" License as described in the "LICENSE" file, 
# which should be included with this package. The terms are also available at 
# http://www.hardcoded.net/licenses/bsd_license

from collections import namedtuple

from PyQt5.QtCore import pyqtSignal, QObject
from PyQt5.QtWidgets import QAction

from hscommon.trans import trget
from hscommon.util import dedupe

tr = trget('qtlib')

MenuEntry = namedtuple('MenuEntry', 'menu fixedItemCount')

class Recent(QObject):
    def __init__(self, app, prefName, maxItemCount=10, **kwargs):
        super().__init__(**kwargs)
        self._app = app
        self._menuEntries = []
        self._prefName = prefName
        self._maxItemCount = maxItemCount
        self._items = []
        self._loadFromPrefs()
        
        self._app.willSavePrefs.connect(self._saveToPrefs)
    
    #--- Private
    def _loadFromPrefs(self):
        items = getattr(self._app.prefs, self._prefName)
        if not isinstance(items, list):
            items = []
        self._items = items
    
    def _insertItem(self, item):
        self._items = dedupe([item] + self._items)[:self._maxItemCount]
    
    def _refreshMenu(self, menuEntry):
        menu, fixedItemCount = menuEntry
        for action in menu.actions()[fixedItemCount:]:
            menu.removeAction(action)
        for item in self._items:
            action = QAction(item, menu)
            action.setData(item)
            action.triggered.connect(self.menuItemWasClicked)
            menu.addAction(action)
        menu.addSeparator()
        action = QAction(tr("Clear List"), menu)
        action.triggered.connect(self.clear)
        menu.addAction(action)
    
    def _refreshAllMenus(self):
        for menuEntry in self._menuEntries:
            self._refreshMenu(menuEntry)
    
    def _saveToPrefs(self):
        setattr(self._app.prefs, self._prefName, self._items)
    
    #--- Public
    def addMenu(self, menu):
        menuEntry = MenuEntry(menu, len(menu.actions()))
        self._menuEntries.append(menuEntry)
        self._refreshMenu(menuEntry)
    
    def clear(self):
        self._items = []
        self._refreshAllMenus()
        self.itemsChanged.emit()
    
    def insertItem(self, item):
        self._insertItem(str(item))
        self._refreshAllMenus()
        self.itemsChanged.emit()
    
    def isEmpty(self):
        return not bool(self._items)
    
    #--- Event Handlers
    def menuItemWasClicked(self):
        action = self.sender()
        if action is not None:
            item = action.data()
            self.mustOpenItem.emit(item)
            self._refreshAllMenus()
    
    #--- Signals
    mustOpenItem = pyqtSignal(str)
    itemsChanged = pyqtSignal()