Various Improvements

Author: SeakyLuo

Python Files/FileConverter/FileConverter.py

@@ -14,6 +14,7 @@ def __init__(self, master):
         self.frames = [Frame(self) for _ in range(3)]
         self.selectButton = Button(self.frames[0], text = 'Select File', command = self.select)
         self.convertButton = Button(self.frames[0], text = 'Convert', command = self.convert)
+        self.revertButton = Button(self.frames[0], text = 'Revert', command = self.revert)
         self.fileLabel = Label(self.frames[1], text = 'File: ')
         self.filenameLabel = Label(self.frames[1])
         self.toLabel = Label(self.frames[1], text = 'Format: ')
@@ -25,30 +26,52 @@ def __init__(self, master):
             self.toEntry.select_range(0, END)
         for i, w in enumerate(self.frames):
             w.grid(row = i, column = 0, sticky = NSEW)
-        for i, (w1, w2, w3) in enumerate(zip([self.selectButton, self.convertButton],
-                                             [self.fileLabel, self.filenameLabel],
-                                             [self.toLabel, self.toEntry])):
-            w1.grid(row = 0, column = i, sticky = NSEW)
-            w2.grid(row = 0, column = i)
-            w3.grid(row = 1, column = i, sticky = NSEW)
+        for i, w in enumerate([self.selectButton, self.convertButton, self.revertButton]):
+            w.grid(row = 0, column = i, sticky = NSEW)
+        for i, (w1, w2) in enumerate(zip([self.fileLabel, self.filenameLabel],
+                                         [self.toLabel, self.toEntry])):
+            w1.grid(row = 0, column = i)
+            w2.grid(row = 1, column = i, sticky = NSEW)
+        self.lastConversion = ()
 
     def select(self):
         filename = filedialog.askopenfilename(initialdir = self.settings.setdefault(LAST_DIR, ''), \
                                               title = 'Select a File')
         if not filename: return
         self.settings[LAST_DIR] = os.path.dirname(filename)
         self.filenameLabel['text'] = filename
+        self.lastConversion = ()
 
     def convert(self):
         filename = self.filenameLabel['text']
         fileFormat = self.toEntry.get()
-        if not filename or not fileFormat: return
         if fileFormat.startswith('.'):
             fileFormat = fileFormat[1:]
-            if not fileFormat: return
+        if not filename or not fileFormat:
+            messagebox.showerror(title = 'Error', message = 'Nothing to Convert!')
+            return
         self.settings[LAST_FORMAT] = fileFormat
-        os.rename(filename, filename[:filename.find('.') + 1] + fileFormat)
-        messagebox.showinfo(title = 'Finished', message = 'Done!')
+        dot = filename.find('.')
+        newFileName = filename + '.' + fileFormat if dot == -1 else filename[:dot + 1] + fileFormat
+        self.__rename(filename, newFileName, 'Renaming Done!')
+
+    def revert(self):
+        if not self.lastConversion:
+            messagebox.showerror(title = 'Error', message = 'Nothing to Revert!')
+            return
+        fromFile, toFile = self.lastConversion
+        self.__rename(toFile, fromFile, 'Reversion Done!')
+
+    def __rename(self, fromFile, toFile, doneMessage):
+        try:
+            os.rename(fromFile, toFile)
+        except:
+            messagebox.showerror(title = 'Error', message = 'File not found!')
+            return False
+        self.filenameLabel['text'] = toFile
+        self.lastConversion = (fromFile, toFile)
+        messagebox.showinfo(title = 'Finished', message = doneMessage)
+        return True
 
 root = Tk()
 app = Converter(root)