Enhancement #1886079: default value for custom columns

src/calibre/db/cache.py

@@ -92,6 +92,29 @@ def _add_newbook_tag(mi):
                     mi.tags.append(tag)
 
 
+def _add_default_custom_column_values(mi, fm):
+    cols = fm.custom_field_metadata(include_composites=False)
+    for cc,col in iteritems(cols):
+        dv = col['display'].get('default_value', '')
+        try:
+            if dv:
+                if not mi.get_user_metadata(cc, make_copy=False):
+                    mi.set_user_metadata(cc, col)
+                dt = col['datatype']
+                if dt == 'bool':
+                    dv = {_('yes'): 'true', _('no'): 'false'}.get(icu_lower(dv), '')
+                elif dt == 'datetime' and icu_lower(dv) == _('now'):
+                    dv = nowf()
+                elif dt == 'rating':
+                    try:
+                        dv = int(dv) * 2
+                    except:
+                        dv = None
+                mi.set(cc, dv)
+        except:
+            pass
+
+
 dynamic_category_preferences = frozenset({'grouped_search_make_user_categories', 'grouped_search_terms', 'user_categories'})
 
 
@@ -1571,6 +1594,7 @@ class Cache(object):
             mi.tags = list(mi.tags)
         if apply_import_tags:
             _add_newbook_tag(mi)
+            _add_default_custom_column_values(mi, self.field_metadata)
         if not add_duplicates and self._has_book(mi):
             return
         series_index = (self._get_next_series_num_for(mi.series) if mi.series_index is None else mi.series_index)

src/calibre/gui2/preferences/create_custom_column.py

@@ -177,6 +177,10 @@ class CreateCustomColumn(QDialog):
             self.comments_type.setCurrentIndex(idx)
         elif ct == 'rating':
             self.allow_half_stars.setChecked(bool(c['display'].get('allow_half_stars', False)))
+
+        if ct not in ['composite', '*composite']:
+            self.default_value.setText(c['display'].get('default_value', ''))
+
         self.datatype_changed()
         if ct in ['text', 'composite', 'enumeration']:
             self.use_decorations.setChecked(c['display'].get('use_decorations', False))
@@ -390,6 +394,15 @@ class CreateCustomColumn(QDialog):
         l.addWidget(cch)
         add_row(None, l)
 
+        # Default value
+        self.default_value = dv = QLineEdit(self)
+        dv.setToolTip('<p>' + _('Default value when a new book is added to the '
+            'library. For Date columns enter the word "now" or the date as '
+            'yyyy-mm-dd. For Yes/No columns enter "Yes" or "No". For Text with '
+            'a fixed set of values enter one of the permitted values. For '
+            'Rating columns enter a number between 0 and 5.') + '</p>')
+        self.default_value_label = add_row(_('Default value'), dv)
+
         self.resize(self.sizeHint())
     # }}}
 
@@ -456,6 +469,8 @@ class CreateCustomColumn(QDialog):
             getattr(self, 'composite_'+x).setVisible(col_type in ['composite', '*composite'])
         for x in ('box', 'default_label', 'label', 'colors', 'colors_label'):
             getattr(self, 'enum_'+x).setVisible(col_type == 'enumeration')
+        for x in ('value_label', 'value'):
+            getattr(self, 'default_'+x).setVisible(col_type not in ['composite', '*composite'])
         self.use_decorations.setVisible(col_type in ['text', 'composite', 'enumeration'])
         self.is_names.setVisible(col_type == '*text')
         is_comments = col_type == 'comments'
@@ -566,6 +581,10 @@ class CreateCustomColumn(QDialog):
 
         if col_type in ['text', 'composite', 'enumeration'] and not is_multiple:
             display_dict['use_decorations'] = self.use_decorations.checkState()
+
+        if col_type != 'composite':
+            display_dict['default_value'] = unicode_type(self.default_value.text())
+
         display_dict['description'] = self.description_box.text().strip()
 
         if not self.editing_col: