feat: Remove shelve picture cache

- Remove shelve picture cache as it has had a fair number of historical
  issues.  Original issue for which it was added should be long
  resolved.  Additionally this allows additional consolidation of the
  various cache code and potentially dbs in the future.
- Remove all related preferences and related code for changing cache
  backend between sqlite and shelve.

qt/app.py

@@ -192,7 +192,6 @@ class DupeGuru(QObject):
             scanned_tags.add("year")
         self.model.options["scanned_tags"] = scanned_tags
         self.model.options["match_scaled"] = self.prefs.match_scaled
-        self.model.options["picture_cache_type"] = self.prefs.picture_cache_type
         self.model.options["include_exists_check"] = self.prefs.include_exists_check
         self.model.options["rehash_ignore_mtime"] = self.prefs.rehash_ignore_mtime
 

qt/pe/preferences_dialog.py

@@ -4,11 +4,9 @@
 # which should be included with this package. The terms are also available at
 # http://www.gnu.org/licenses/gpl-3.0.html
 
-from PyQt5.QtWidgets import QFormLayout
-from PyQt5.QtCore import Qt
+
 from hscommon.trans import trget
 from hscommon.plat import ISLINUX
-from qt.radio_box import RadioBox
 from core.scanner import ScanType
 from core.app import AppMode
 
@@ -35,11 +33,6 @@ class PreferencesDialog(PreferencesDialogBase):
         )
         self.widgetsVLayout.addWidget(self.ignoreHardlinkMatches)
 
-        self.cacheTypeRadio = RadioBox(self, items=["Sqlite", "Shelve"], spread=False)
-        cache_form = QFormLayout()
-        cache_form.setLabelAlignment(Qt.AlignLeft)
-        cache_form.addRow(tr("Picture cache mode:"), self.cacheTypeRadio)
-        self.widgetsVLayout.addLayout(cache_form)
         self._setupBottomPart()
 
     def _setupDisplayPage(self):
@@ -64,7 +57,6 @@ show scrollbars to span the view around"
 
     def _load(self, prefs, setchecked, section):
         setchecked(self.matchScaledBox, prefs.match_scaled)
-        self.cacheTypeRadio.selected_index = 1 if prefs.picture_cache_type == "shelve" else 0
 
         # Update UI state based on selected scan type
         scan_type = prefs.get_scan_type(AppMode.PICTURE)
@@ -75,6 +67,5 @@ show scrollbars to span the view around"
 
     def _save(self, prefs, ischecked):
         prefs.match_scaled = ischecked(self.matchScaledBox)
-        prefs.picture_cache_type = "shelve" if self.cacheTypeRadio.selected_index == 1 else "sqlite"
         prefs.details_dialog_override_theme_icons = ischecked(self.details_dialog_override_theme_icons)
         prefs.details_dialog_viewers_show_scrollbars = ischecked(self.details_dialog_viewers_show_scrollbars)

qt/preferences.py

@@ -225,7 +225,6 @@ class Preferences(PreferencesBase):
         self.scan_tag_genre = get("ScanTagGenre", self.scan_tag_genre)
         self.scan_tag_year = get("ScanTagYear", self.scan_tag_year)
         self.match_scaled = get("MatchScaled", self.match_scaled)
-        self.picture_cache_type = get("PictureCacheType", self.picture_cache_type)
 
     def reset(self):
         self.filter_hardness = 95
@@ -278,7 +277,6 @@ class Preferences(PreferencesBase):
         self.scan_tag_genre = False
         self.scan_tag_year = False
         self.match_scaled = False
-        self.picture_cache_type = "sqlite"
 
     def _save_values(self, settings):
         set_ = self.set_value
@@ -332,7 +330,6 @@ class Preferences(PreferencesBase):
         set_("ScanTagGenre", self.scan_tag_genre)
         set_("ScanTagYear", self.scan_tag_year)
         set_("MatchScaled", self.match_scaled)
-        set_("PictureCacheType", self.picture_cache_type)
 
     # scan_type is special because we save it immediately when we set it.
     def get_scan_type(self, app_mode):