dnd universial converter

#!/usr/bin/env python3.9
# Simple drag and drop converter app

import wx
from wx.adv import AboutDialogInfo, GenericAboutBox
from threading import Thread
from pathlib import Path
import os
import sys
import numpy as np
import subprocess


choices = ['.m4a', '.mp3', '.acc']

if os.name == 'nt':
    import ctypes
    ctypes.windll.shell32.SetCurrentProcessExplicitAppUserModelID('UniConv_v0.0.0')

class RedirectStdoutToTextCtrl():
    def __init__(self, widget):
        sys.stdout = self
        sys.stderr = self
        self.widget = widget

    def write(self, message):
        self.widget.WriteText(message)
        return len(message)

    def read(self):
        pass

    def __del__(self):
        sys.stdout = sys.__stdout__


class GUI(wx.Frame):
    def __init__(self, parent, id, title):
        wx.Frame.__init__(self, parent, id, title)
        self.SetSize((300, 200))

        # pretty icon
        def getIcon():
            x, y = 256, 256
            img = np.zeros((x*y), dtype='uint8')

            for i in range(y):
                for j in range(x):
                    f = j/x
                    img[i*y+j] = int((4*f**3 if f < 0.5 else 1-(-2*f+2)**3/2)*256) # cubic ease function

            img = np.repeat(img, 3)
            icon = wx.Bitmap.FromBuffer(x, y, img)
            return icon
        self.SetIcon(wx.Icon(getIcon()))

        # main panel
        self.panel = wx.Panel(self)
        self.panel.SetDropTarget(self.FileDrop(self)) # set DND

        # main sizer
        vSizer = wx.BoxSizer(wx.VERTICAL)
        self.panel.SetSizer(vSizer)

        # dropdown list
        self.comboBox = wx.ComboBox(self.panel, choices=choices)
        vSizer.Add(self.comboBox, flag=wx.EXPAND|wx.ALL, border=5)
        self.comboBox.SetSelection(0)

        # logger panel
        self.loggerPanel = wx.Panel(self.panel)
        vSizer.Add(self.loggerPanel, flag=wx.EXPAND, proportion=1)
        self.logsUI(self.loggerPanel)

        self.Centre()
        self.panel.Layout()

    def logsUI(self, panel):
        sizer = wx.BoxSizer(wx.VERTICAL)
        panel.SetSizer(sizer)

        self.logsTextCtrl = wx.TextCtrl(panel, style=wx.TE_MULTILINE, size=(222, 0))
        sizer.Add(self.logsTextCtrl, flag=wx.ALL|wx.EXPAND, border=5, proportion=1)
        self.logsTextCtrl.WriteText('Right click to clear the logs.\n\n')
        self.stdout = RedirectStdoutToTextCtrl(self.logsTextCtrl)

        def onContextMenu(evt):
            menu = wx.Menu()

            clearLog = menu.Append(wx.ID_ANY, "Clear log")
            menu.Bind(wx.EVT_MENU, lambda _: self.logsTextCtrl.Clear(), id=clearLog.GetId())

            self.logsTextCtrl.PopupMenu(menu)
        self.logsTextCtrl.Bind(wx.EVT_CONTEXT_MENU, onContextMenu)

    def workerThread(self, files, extension):
        failed_files = []

        for i, file in enumerate(files):
            print(f'\nFile {i+1}/{len(files)}')
            file_path = Path(file).resolve()
            output_path = str(file_path.parent)

            file_name = f'%s{extension}' % str(file_path.stem)
            output_file = os.path.join(output_path, file_name)

            # process file
            result = False
            try:
                result = subprocess.run(['ffmpeg', '-i', file, '-vn', '-acodec', 'copy', output_file]) # redirecting is a bit harder. https://docs.python.org/3/library/subprocess.html#subprocess.Popen.communicate
                result = result.returncode == 0
            except:
                print('An error has occured!')

            if not result:
                failed_files.append(file)

        if failed_files:
            failMsg = f'\n{len(failed_files)} file(s) failed to process:'
            print(failMsg)
            for failed_file in failed_files:
                print(failed_file)
            wx.MessageDialog(self, 'An error has occurred. Please check the log.', 'Error', wx.OK|wx.ICON_ERROR).ShowModal()
        else:
            print('\nAll files converted.')

    class FileDrop(wx.FileDropTarget):
        def __init__(self, parent):
            wx.FileDropTarget.__init__(self)
            self.parent = parent

        def OnDropFiles(self, x, y, filenames):
            extension = self.parent.comboBox.GetString(self.parent.comboBox.GetSelection())
            Thread(target=self.parent.workerThread, daemon=True, args=(filenames, extension)).start()
            return True

def main():
    app = wx.App()
    gui = GUI(None, wx.ID_ANY, 'UniConv')
    gui.Show(True)
    app.MainLoop()

if __name__ == '__main__':
    main()