Add right click menu to the formats list in the edit metadata dialog that allwos you to restore a format from its original easily

src/calibre/gui2/metadata/basic_widgets.py

@@ -11,10 +11,10 @@ import textwrap, re, os
 
 from PyQt4.Qt import (Qt, QDateEdit, QDate, pyqtSignal, QMessageBox,
     QIcon, QToolButton, QWidget, QLabel, QGridLayout, QApplication,
-    QDoubleSpinBox, QListWidgetItem, QSize, QPixmap, QDialog,
-    QPushButton, QSpinBox, QLineEdit, QSizePolicy, QDialogButtonBox)
+    QDoubleSpinBox, QListWidgetItem, QSize, QPixmap, QDialog, QMenu,
+    QPushButton, QSpinBox, QLineEdit, QSizePolicy, QDialogButtonBox, QAction)
 
-from calibre.gui2.widgets import EnLineEdit, FormatList, ImageView
+from calibre.gui2.widgets import EnLineEdit, FormatList as _FormatList, ImageView
 from calibre.gui2.complete import MultiCompleteLineEdit, MultiCompleteComboBox
 from calibre.utils.icu import sort_key
 from calibre.utils.config import tweaks, prefs
@@ -33,6 +33,7 @@ from calibre.gui2.comments_editor import Editor
 from calibre.library.comments import comments_to_html
 from calibre.gui2.dialogs.tag_editor import TagEditor
 from calibre.utils.icu import strcmp
+from calibre.ptempfile import PersistentTemporaryFile
 
 def save_dialog(parent, title, msg, det_msg=''):
     d = QMessageBox(parent)
@@ -572,7 +573,9 @@ class BuddyLabel(QLabel): # {{{
         self.setAlignment(Qt.AlignRight|Qt.AlignVCenter)
 # }}}
 
-class Format(QListWidgetItem): # {{{
+# Formats {{{
+
+class Format(QListWidgetItem):
 
     def __init__(self, parent, ext, size, path=None, timestamp=None):
         self.path = path
@@ -588,13 +591,52 @@ class Format(QListWidgetItem): # {{{
             self.setToolTip(text)
             self.setStatusTip(text)
 
-# }}}
+class OrigAction(QAction):
 
-class FormatsManager(QWidget): # {{{
+    restore_fmt = pyqtSignal(object)
+
+    def __init__(self, fmt, parent):
+        self.fmt = fmt.replace('ORIGINAL_', '')
+        QAction.__init__(self, _('Restore %s from the original')%self.fmt, parent)
+        self.triggered.connect(self._triggered)
+
+    def _triggered(self):
+        self.restore_fmt.emit(self.fmt)
+
+class FormatList(_FormatList):
+
+    restore_fmt = pyqtSignal(object)
 
     def __init__(self, parent):
+        _FormatList.__init__(self, parent)
+        self.setContextMenuPolicy(Qt.DefaultContextMenu)
+
+    def contextMenuEvent(self, event):
+        originals = [self.item(x).ext.upper() for x in range(self.count())]
+        originals = [x for x in originals if x.startswith('ORIGINAL_')]
+        if not originals:
+            return
+        self.cm = cm = QMenu(self)
+        for fmt in originals:
+            action = OrigAction(fmt, cm)
+            action.restore_fmt.connect(self.restore_fmt)
+            cm.addAction(action)
+        cm.popup(event.globalPos())
+        event.accept()
+
+    def remove_format(self, fmt):
+        for i in range(self.count()):
+            f = self.item(i)
+            if f.ext.upper() == fmt.upper():
+                self.takeItem(i)
+                break
+
+class FormatsManager(QWidget):
+
+    def __init__(self, parent, copy_fmt):
         QWidget.__init__(self, parent)
         self.dialog = parent
+        self.copy_fmt = copy_fmt
         self.changed = False
 
         self.l = l = QGridLayout()
@@ -628,6 +670,7 @@ class FormatsManager(QWidget): # {{{
         self.formats = FormatList(self)
         self.formats.setAcceptDrops(True)
         self.formats.formats_dropped.connect(self.formats_dropped)
+        self.formats.restore_fmt.connect(self.restore_fmt)
         self.formats.delete_format.connect(self.remove_format)
         self.formats.itemDoubleClicked.connect(self.show_format)
         self.formats.setDragDropMode(self.formats.DropOnly)
@@ -640,7 +683,7 @@ class FormatsManager(QWidget): # {{{
         l.addWidget(self.remove_format_button,        2, 2, 1, 1)
         l.addWidget(self.formats,                     0, 1, 3, 1)
 
-
+        self.temp_files = []
 
     def initialize(self, db, id_):
         self.changed = False
@@ -694,6 +737,16 @@ class FormatsManager(QWidget): # {{{
                              [(_('Books'), BOOK_EXTENSIONS)])
         self._add_formats(files)
 
+    def restore_fmt(self, fmt):
+        pt = PersistentTemporaryFile(suffix='_restore_fmt.'+fmt.lower())
+        ofmt = 'ORIGINAL_'+fmt
+        with pt:
+            self.copy_fmt(ofmt, pt)
+        self._add_formats((pt.name,))
+        self.temp_files.append(pt.name)
+        self.changed = True
+        self.formats.remove_format(ofmt)
+
     def _add_formats(self, paths):
         added = False
         if not paths:
@@ -774,6 +827,13 @@ class FormatsManager(QWidget): # {{{
 
     def break_cycles(self):
         self.dialog = None
+        self.copy_fmt = None
+        for name in self.temp_files:
+            try:
+                os.remove(name)
+            except:
+                pass
+        self.temp_files = []
 # }}}
 
 class Cover(ImageView): # {{{

src/calibre/gui2/metadata/single.py

@@ -145,7 +145,7 @@ class MetadataSingleDialogBase(ResizableDialog):
         self.series_index = SeriesIndexEdit(self, self.series)
         self.basic_metadata_widgets.extend([self.series, self.series_index])
 
-        self.formats_manager = FormatsManager(self)
+        self.formats_manager = FormatsManager(self, self.copy_fmt)
         self.basic_metadata_widgets.append(self.formats_manager)
         self.formats_manager.metadata_from_format_button.clicked.connect(
                 self.metadata_from_format)
@@ -240,6 +240,8 @@ class MetadataSingleDialogBase(ResizableDialog):
         else:
             self.view_format.emit(self.book_id, fmt)
 
+    def copy_fmt(self, fmt, f):
+        self.db.copy_format_to(self.book_id, fmt, f, index_is_id=True)
 
     def do_layout(self):
         raise NotImplementedError()