Remove per editor saves as they cannot be implemented robustly

Also, show busy cursor when running any potentially long winded job.

Now that we have gotten rid of per editor saves, we track sync status of
editor with container, instead, and when performing any task that
operates on the container directly, sync open editors to the container.
This avoids the confusing warning about modified files.

src/calibre/gui2/tweak_book/boss.py

@@ -8,7 +8,7 @@ __copyright__ = '2013, Kovid Goyal <kovid at kovidgoyal.net>'
 
 import tempfile, shutil, sys, os
 from collections import OrderedDict
-from functools import partial
+from functools import partial, wraps
 
 from PyQt4.Qt import (
     QObject, QApplication, QDialog, QGridLayout, QLabel, QSize, Qt, QCursor,
@@ -38,6 +38,21 @@ def get_container(*args, **kwargs):
     kwargs['tweak_mode'] = True
     return _gc(*args, **kwargs)
 
+class BusyCursor(object):
+
+    def __enter__(self):
+        QApplication.setOverrideCursor(QCursor(Qt.WaitCursor))
+
+    def __exit__(self, *args):
+        QApplication.restoreOverrideCursor()
+
+def in_thread_job(func):
+    @wraps(func)
+    def ans(*args, **kwargs):
+        with BusyCursor():
+            return func(*args, **kwargs)
+    return ans
+
 class Boss(QObject):
 
     def __init__(self, parent):
@@ -73,8 +88,7 @@ class Boss(QObject):
                 ed.apply_settings()
 
     def mark_requested(self, name, action):
-        if not self.check_opf_dirtied():
-            return
+        self.commit_dirty_opf()
         c = current_container()
         if action == 'cover':
             mark_as_cover(current_container(), name)
@@ -161,7 +175,7 @@ class Boss(QObject):
         for name, ed in tuple(editors.iteritems()):
             if c.has_name(name):
                 ed.replace_data(c.raw_data(name))
-                ed.is_modified = False
+                ed.is_synced_to_container = True
             else:
                 self.close_editor(name)
 
@@ -172,9 +186,9 @@ class Boss(QObject):
         self.update_editors_from_container()
         self.set_modified()
 
+    @in_thread_job
     def delete_requested(self, spine_items, other_items):
-        if not self.check_dirtied():
-            return
+        self.commit_all_editors_to_container()
         self.add_savepoint(_('Delete files'))
         c = current_container()
         c.remove_from_spine(spine_items)
@@ -188,17 +202,13 @@ class Boss(QObject):
         if not editors:
             self.gui.preview.clear()
 
-    def check_opf_dirtied(self):
+    def commit_dirty_opf(self):
         c = current_container()
-        if c.opf_name in editors and editors[c.opf_name].is_modified:
-            return question_dialog(self.gui, _('Unsaved changes'), _(
-                'You have unsaved changes in %s. If you proceed,'
-                ' you will lose them. Proceed anyway?') % c.opf_name)
-        return True
+        if c.opf_name in editors and not editors[c.opf_name].is_synced_to_container:
+            self.commit_editor_to_container(c.opf_name)
 
     def reorder_spine(self, items):
-        if not self.check_opf_dirtied():
-            return
+        self.commit_dirty_opf()
         self.add_savepoint(_('Re-order text'))
         c = current_container()
         c.set_spine(items)
@@ -213,8 +223,7 @@ class Boss(QObject):
                 'You must first open a book to tweak, before trying to create new files'
                 ' in it.'), show=True)
 
-        if not self.check_opf_dirtied():
-            return
+        self.commit_dirty_opf()
         d = NewFileDialog(self.gui)
         if d.exec_() != d.Accepted:
             return
@@ -241,8 +250,7 @@ class Boss(QObject):
                 self.edit_file(d.file_name, syntax)
 
     def edit_toc(self):
-        if not self.check_dirtied():
-            return
+        self.commit_all_editors_to_container()
         self.add_savepoint(_('Edit Table of Contents'))
         d = TOCEditor(title=self.current_metadata.title, parent=self.gui)
         if d.exec_() != d.Accepted:
@@ -251,17 +259,17 @@ class Boss(QObject):
         self.update_editors_from_container()
 
     def polish(self, action, name):
-        if not self.check_dirtied():
-            return
-        self.add_savepoint(name)
-        try:
-            report = tweak_polish(current_container(), {action:True})
-        except:
-            self.rewind_savepoint()
-            raise
-        self.apply_container_update_to_gui()
-        from calibre.ebooks.markdown import markdown
-        report = markdown('# %s\n\n'%self.current_metadata.title + '\n\n'.join(report), output_format='html4')
+        self.commit_all_editors_to_container()
+        with BusyCursor():
+            self.add_savepoint(name)
+            try:
+                report = tweak_polish(current_container(), {action:True})
+            except:
+                self.rewind_savepoint()
+                raise
+            self.apply_container_update_to_gui()
+            from calibre.ebooks.markdown import markdown
+            report = markdown('# %s\n\n'%self.current_metadata.title + '\n\n'.join(report), output_format='html4')
         d = QDialog(self.gui)
         d.l = QVBoxLayout()
         d.setLayout(d.l)
@@ -277,8 +285,7 @@ class Boss(QObject):
 
     # Renaming {{{
     def rename_requested(self, oldname, newname):
-        if not self.check_dirtied():
-            return
+        self.commit_all_editors_to_container()
         if guess_type(oldname) != guess_type(newname):
             args = os.path.splitext(oldname) + os.path.splitext(newname)
             if not confirm(
@@ -357,16 +364,12 @@ class Boss(QObject):
             if hasattr(ed, 'fix_html'):
                 ed.fix_html()
         else:
-            if not self.check_dirtied():
-                return
-            QApplication.setOverrideCursor(QCursor(Qt.WaitCursor))
-            try:
+            self.commit_all_editors_to_container()
+            with BusyCursor():
                 self.add_savepoint(_('Fix HTML'))
                 fix_all_html(current_container())
                 self.update_editors_from_container()
                 self.set_modified()
-            finally:
-                QApplication.restoreOverrideCursor()
 
     def pretty_print(self, current):
         if current:
@@ -376,16 +379,12 @@ class Boss(QObject):
                     break
             ed.pretty_print(name)
         else:
-            if not self.check_dirtied():
-                return
-            QApplication.setOverrideCursor(QCursor(Qt.WaitCursor))
-            try:
+            self.commit_all_editors_to_container()
+            with BusyCursor():
                 self.add_savepoint(_('Beautify files'))
                 pretty_all(current_container())
                 self.update_editors_from_container()
                 self.set_modified()
-            finally:
-                QApplication.restoreOverrideCursor()
 
     def mark_selected_text(self):
         ed = self.gui.central.current_editor
@@ -539,8 +538,7 @@ class Boss(QObject):
             count_message(_('Replaced') if replace else _('Found'), count)
             return count
 
-        QApplication.setOverrideCursor(QCursor(Qt.WaitCursor))
-        try:
+        with BusyCursor():
             if action == 'find':
                 return do_find()
             if action == 'replace':
@@ -559,8 +557,6 @@ class Boss(QObject):
                 if marked:
                     return count_message(_('Found'), editor.all_in_marked(pat))
                 return do_all(replace=False)
-        finally:
-            QApplication.restoreOverrideCursor()
 
     def create_checkpoint(self):
         text, ok = QInputDialog.getText(self.gui, _('Choose name'), _(
@@ -569,12 +565,26 @@ class Boss(QObject):
         if ok:
             self.add_savepoint(text)
 
+    def commit_editor_to_container(self, name, container=None):
+        container = container or current_container()
+        ed = editors[name]
+        with container.open(name, 'wb') as f:
+            f.write(ed.data)
+            if container is current_container():
+                ed.is_synced_to_container = True
+
+    def commit_all_editors_to_container(self):
+        with BusyCursor():
+            for name, ed in editors.iteritems():
+                if not ed.is_synced_to_container:
+                    self.commit_editor_to_container(name)
+                    ed.is_synced_to_container = True
+
     def save_book(self):
         c = current_container()
         for name, ed in editors.iteritems():
-            if ed.is_modified:
-                with c.open(name, 'wb') as f:
-                    f.write(ed.data)
+            if ed.is_modified or not ed.is_synced_to_container:
+                self.commit_editor_to_container(name, c)
                 ed.is_modified = False
         self.gui.action_save.setEnabled(False)
         tdir = self.mkdtemp(prefix='save-')
@@ -591,9 +601,8 @@ class Boss(QObject):
         tdir = self.mkdtemp(prefix='save-copy-')
         container = clone_container(c, tdir)
         for name, ed in editors.iteritems():
-            if ed.is_modified:
-                with c.open(name, 'wb') as f:
-                    f.write(ed.data)
+            if ed.is_modified or not ed.is_synced_to_container:
+                self.commit_editor_to_container(name, container)
 
         def do_save(c, path, tdir):
             save_container(c, path)
@@ -627,42 +636,33 @@ class Boss(QObject):
             ed.current_line = num
 
     def split_start_requested(self):
-        if not self.check_dirtied():
-            return self.gui.preview.stop_split()
+        self.commit_all_editors_to_container()
         self.gui.preview.do_start_split()
 
+    @in_thread_job
     def split_requested(self, name, loc):
-        if not self.check_dirtied():
-            return
-        QApplication.setOverrideCursor(QCursor(Qt.WaitCursor))
+        self.commit_all_editors_to_container()
+        self.add_savepoint(_('Split %s') % self.gui.elided_text(name))
         try:
-            self.add_savepoint(_('Split %s') % self.gui.elided_text(name))
-            try:
-                bottom_name = split(current_container(), name, loc)
-            except AbortError:
-                self.rewind_savepoint()
-                raise
-            self.apply_container_update_to_gui()
-            self.edit_file(bottom_name, 'html')
-        finally:
-            QApplication.restoreOverrideCursor()
+            bottom_name = split(current_container(), name, loc)
+        except AbortError:
+            self.rewind_savepoint()
+            raise
+        self.apply_container_update_to_gui()
+        self.edit_file(bottom_name, 'html')
 
+    @in_thread_job
     def merge_requested(self, category, names, master):
-        if not self.check_dirtied():
-            return
-        QApplication.setOverrideCursor(QCursor(Qt.WaitCursor))
+        self.commit_all_editors_to_container()
+        self.add_savepoint(_('Merge files into %s') % self.gui.elided_text(master))
         try:
-            self.add_savepoint(_('Merge files into %s') % self.gui.elided_text(master))
-            try:
-                merge(current_container(), category, names, master)
-            except AbortError:
-                self.rewind_savepoint()
-                raise
-            self.apply_container_update_to_gui()
-            if master in editors:
-                self.show_editor(master)
-        finally:
-            QApplication.restoreOverrideCursor()
+            merge(current_container(), category, names, master)
+        except AbortError:
+            self.rewind_savepoint()
+            raise
+        self.apply_container_update_to_gui()
+        if master in editors:
+            self.show_editor(master)
 
     def sync_editor_to_preview(self, name, lnum):
         editor = self.edit_file(name, 'html')
@@ -695,6 +695,7 @@ class Boss(QObject):
                 editor.init_from_template(data)
             else:
                 editor.data = data
+                editor.is_synced_to_container = True
         editor.modification_state_changed.connect(self.editor_modification_state_changed)
         self.gui.central.add_editor(name, editor)
 
@@ -755,23 +756,22 @@ class Boss(QObject):
         self.gui.preview.start_refresh_timer()
 
     def editor_undo_redo_state_changed(self, *args):
-        self.apply_current_editor_state(update_keymap=False)
+        self.apply_current_editor_state()
 
     def editor_copy_available_state_changed(self, *args):
-        self.apply_current_editor_state(update_keymap=False)
+        self.apply_current_editor_state()
 
     def editor_modification_state_changed(self, is_modified):
-        self.apply_current_editor_state(update_keymap=False)
+        self.apply_current_editor_state()
         if is_modified:
             self.set_modified()
     # }}}
 
-    def apply_current_editor_state(self, update_keymap=True):
+    def apply_current_editor_state(self):
         ed = self.gui.central.current_editor
         if ed is not None:
             actions['editor-undo'].setEnabled(ed.undo_available)
             actions['editor-redo'].setEnabled(ed.redo_available)
-            actions['editor-save'].setEnabled(ed.is_modified)
             actions['editor-cut'].setEnabled(ed.copy_available)
             actions['editor-copy'].setEnabled(ed.cut_available)
             actions['go-to-line-number'].setEnabled(ed.has_line_numbers)
@@ -793,7 +793,7 @@ class Boss(QObject):
                 name = n
         if not name:
             return
-        if editor.is_modified:
+        if editor.is_modified or not editor.is_synced_to_container:
             if not question_dialog(self.gui, _('Unsaved changes'), _(
                 'There are unsaved changes in %s. Are you sure you want to close'
                 ' this editor?') % name):
@@ -807,31 +807,6 @@ class Boss(QObject):
         if not editors:
             self.gui.preview.clear()
 
-    def do_editor_save(self):
-        ed = self.gui.central.current_editor
-        if ed is None:
-            return
-        name = None
-        for n, x in editors.iteritems():
-            if x is ed:
-                name = n
-                break
-        if name is None:
-            return
-        c = current_container()
-        with c.open(name, 'wb') as f:
-            f.write(ed.data)
-        ed.is_modified = False
-        tdir = self.mkdtemp(prefix='save-')
-        container = clone_container(c, tdir)
-        self.save_manager.schedule(tdir, container)
-        is_modified = False
-        for ed in editors.itervalues():
-            if ed.is_modified:
-                is_modified = True
-                break
-        self.gui.action_save.setEnabled(is_modified)
-
     # Shutdown {{{
     def quit(self):
         if not self.confirm_quit():

src/calibre/gui2/tweak_book/editor/widget.py

@@ -29,14 +29,15 @@ class Editor(QMainWindow):
         QMainWindow.__init__(self, parent)
         if parent is None:
             self.setWindowFlags(Qt.Widget)
+        self.is_synced_to_container = False
         self.syntax = syntax
         self.editor = TextEdit(self)
         self.setCentralWidget(self.editor)
-        self.editor.modificationChanged.connect(self.modification_state_changed.emit)
         self.create_toolbars()
         self.undo_available = False
         self.redo_available = False
         self.copy_available = self.cut_available = False
+        self.editor.modificationChanged.connect(self._modification_state_changed)
         self.editor.undoAvailable.connect(self._undo_available)
         self.editor.redoAvailable.connect(self._redo_available)
         self.editor.textChanged.connect(self._data_changed)
@@ -124,7 +125,7 @@ class Editor(QMainWindow):
     def create_toolbars(self):
         self.action_bar = b = self.addToolBar(_('File actions tool bar'))
         b.setObjectName('action_bar')  # Needed for saveState
-        for x in ('save', 'undo', 'redo'):
+        for x in ('undo', 'redo'):
             try:
                 b.addAction(actions['editor-%s' % x])
             except KeyError:
@@ -155,7 +156,12 @@ class Editor(QMainWindow):
         self.editor.cursorPositionChanged.disconnect()
         self.editor.setPlainText('')
 
+    def _modification_state_changed(self):
+        self.is_synced_to_container = self.is_modified
+        self.modification_state_changed.emit(self.is_modified)
+
     def _data_changed(self):
+        self.is_synced_to_container = False
         self.data_changed.emit(self)
 
     def _undo_available(self, available):

src/calibre/gui2/tweak_book/ui.py

@@ -186,7 +186,7 @@ class Main(MainWindow):
                                       _('Revert book to before the last action (Undo)'))
         self.action_global_redo = reg('forward.png', _('&Revert to after'), self.boss.do_global_redo, 'global-redo', 'Ctrl+Right',
                                       _('Revert book state to after the next action (Redo)'))
-        self.action_save = reg('save.png', _('&Save'), self.boss.save_book, 'save-book', 'Ctrl+Shift+S', _('Save book'))
+        self.action_save = reg('save.png', _('&Save'), self.boss.save_book, 'save-book', 'Ctrl+S', _('Save book'))
         self.action_save.setEnabled(False)
         self.action_save_copy = reg('save.png', _('Save a &copy'), self.boss.save_copy, 'save-copy', 'Ctrl+Alt+S', _('Save a copy of the book'))
         self.action_quit = reg('quit.png', _('&Quit'), self.boss.quit, 'quit', 'Ctrl+Q', _('Quit'))
@@ -198,8 +198,6 @@ class Main(MainWindow):
                                       _('Undo typing'))
         self.action_editor_redo = reg('edit-redo.png', _('&Redo'), self.boss.do_editor_redo, 'editor-redo', 'Ctrl+Y',
                                       _('Redo typing'))
-        self.action_editor_save = reg('save.png', _('&Save'), self.boss.do_editor_save, 'editor-save', 'Ctrl+S',
-                                      _('Save changes to the current file'))
         self.action_editor_cut = reg('edit-cut.png', _('C&ut text'), self.boss.do_editor_cut, 'editor-cut', ('Ctrl+X', 'Shift+Delete', ),
                                       _('Cut text'))
         self.action_editor_copy = reg('edit-copy.png', _('&Copy text'), self.boss.do_editor_copy, 'editor-copy', ('Ctrl+C', 'Ctrl+Insert'),