RefactoringRope/RefactoringDialogBase.py

# -*- coding: utf-8 -*-

# Copyright (c) 2011 Detlev Offenbach <detlev@die-offenbachs.de>
#

"""
Module implementing the Refactoring dialog base class.
"""

from PyQt4.QtCore import Qt
from PyQt4.QtGui import QDialog, QApplication

from E5Gui.E5Application import e5App

from ChangesPreviewDialog import ChangesPreviewDialog
from ProgressHandle import ProgressHandle


class RefactoringDialogBase(QDialog):
    """
    Class implementing the Refactoring dialog base class.
    """
    def __init__(self, refactoring, title, parent=None):
        """
        Constructor
        
        @param refactoring reference to the main refactoring object
            (Refactoring)
        @param title title of the dialog (string or QString)
        @param parent reference to the parent widget (QWidget)
        """
        QDialog.__init__(self, parent)
        self.setAttribute(Qt.WA_DeleteOnClose)
        self.setWindowTitle(title)
        
        self._refactoring = refactoring
        self._title = title
        self.__handle = None
    
    def __createProgressHandle(self, interruptable=True):
        """
        Private method to create a TaskHandle to update a progress dialog.
        
        @param interruptable flag indicating, that the task may be 
            interrupted (boolean)
        """
        self.__handle = ProgressHandle(self._title, interruptable, self)
        self.__handle.show()
        QApplication.processEvents()
    
    def _calculateChanges(self, handle):
        """
        Protected method to calculate the changes.
        
        @param handle reference to the task handle
            (rope.base.taskhandle.TaskHandle)
        @return reference to the Changes object (rope.base.change.ChangeSet)
        """
        raise NotImplementedError("_calculateChanges must be overridden.")
    
    def __getChanges(self):
        """
        Private method to build the Changes object.
        
        @return reference to the Changes object (rope.base.change.ChangeSet)
        """
        self.__createProgressHandle()
        changes = self._calculateChanges(self.__handle)
        self.__handle.reset()
        self.__handle = None
        
        return changes
    
    def previewChanges(self):
        """
        Public method to preview the changes.
        """
        changes = self.__getChanges()
        
        if changes is not None:
            dlg = ChangesPreviewDialog(changes, self)
            if dlg.exec_() == QDialog.Accepted:
                self.applyChanges(changes)
    
    def applyChanges(self, changes = None):
        """
        Public method to apply the changes.
        
        @param reference to the Changes object (rope.base.change.ChangeSet)
        """
        if changes is None:
            changes = self.__getChanges()
        
        if changes is not None:
            self.__createProgressHandle(False)
            try:
                self._refactoring.getProject().do(changes, self.__handle)
            except Exception as err:
                self._refactoring.handleRopeError(
                    err, self._title, self.__handle)
            self.__handle.reset()
            self.__handle = None
            
            self._refactoring.refreshEditors(changes)
            p = e5App().getObject("Project")
            if p.isDirty():
                p.saveProject()
        
        self.accept()