Implement ticket #8504: Save previous filename import patterns and store them in a combo box.

src/calibre/ebooks/metadata/meta.py

@@ -142,7 +142,13 @@ def metadata_from_filename(name, pat=None):
     name = name.rpartition('.')[0]
     mi = MetaInformation(None, None)
     if pat is None:
-        pat = re.compile(prefs.get('filename_pattern'))
+        pat_re = prefs.get('filename_pattern')
+        if isinstance(pat_re, list):
+            if pat_re:
+                pat_re = pat_re[0]
+            else:
+                pat_re = ''
+        pat = re.compile(pat_re)
     name = name.replace('_', ' ')
     match = pat.search(name)
     if match is not None:

src/calibre/gui2/filename_pattern.ui

@@ -43,7 +43,17 @@ p, li { white-space: pre-wrap; }
      </property>
      <layout class="QVBoxLayout">
       <item>
-       <widget class="QLineEdit" name="re"/>
+       <widget class="QComboBox" name="re">
+        <property name="editable">
+         <bool>true</bool>
+        </property>
+        <property name="maxCount">
+         <number>10</number>
+        </property>
+        <property name="insertPolicy">
+         <enum>QComboBox::InsertAtTop</enum>
+        </property>
+       </widget>
       </item>
      </layout>
     </widget>
@@ -94,8 +104,8 @@ p, li { white-space: pre-wrap; }
             <rect>
              <x>0</x>
              <y>0</y>
-             <width>301</width>
-             <height>234</height>
+             <width>277</width>
+             <height>276</height>
             </rect>
            </property>
            <layout class="QGridLayout" name="gridLayout_2">

src/calibre/gui2/widgets.py

@@ -67,17 +67,21 @@ class FilenamePattern(QWidget, Ui_Form):
         self.setupUi(self)
 
         self.connect(self.test_button, SIGNAL('clicked()'), self.do_test)
-        self.connect(self.re, SIGNAL('returnPressed()'), self.do_test)
-        self.initialize()
-        self.re.textChanged.connect(lambda x: self.changed_signal.emit())
+        self.connect(self.re.lineEdit(), SIGNAL('returnPressed()'), self.do_test)
+        self.re.lineEdit().textChanged.connect(lambda x: self.changed_signal.emit())
 
     def initialize(self, defaults=False):
         if defaults:
             val = prefs.defaults['filename_pattern']
         else:
             val = prefs['filename_pattern']
-        self.re.setText(val)
-
+        if isinstance(val, list):
+            if len(val) > 0:
+                for v in val:
+                    self.re.addItem(v)
+                self.re.setCurrentIndex(0)
+        else:
+            self.re.lineEdit().setText(val if val else '')
 
     def do_test(self):
         try:
@@ -110,12 +114,16 @@ class FilenamePattern(QWidget, Ui_Form):
 
 
     def pattern(self):
-        pat = unicode(self.re.text())
+        pat = unicode(self.re.lineEdit().text())
         return re.compile(pat)
 
     def commit(self):
-        pat = self.pattern().pattern
-        prefs['filename_pattern'] = pat
+        pat = []
+        patterns = [unicode(self.re.lineEdit().text())] + [unicode(self.re.itemText(i)) for i in xrange(self.re.count())]
+        for p in patterns[:14]:
+            if p not in pat:
+                pat.append(p)
+        prefs['filename_pattern'] = pat 
         return pat