app.py

import os
import shutil
import streamlit as st
from pytube import YouTube
import platform

def get_default_download_folder():
    system_platform = platform.system()
    if system_platform == "Windows":
        return os.path.join(os.path.expanduser("~"), "Downloads")
    elif system_platform == "Linux":
        return os.path.join(os.path.expanduser("~"), "Downloads")
    elif system_platform == "Darwin":
        return os.path.join(os.path.expanduser("~"), "Downloads")
    elif system_platform == "Android":
        return "/storage/emulated/0/Download"  # Default Downloads folder path on Android
    else:
        raise NotImplementedError("Platform not supported")

def download_video(url):
    try:
        yt = YouTube(url)
        streams = yt.streams.filter(progressive=True, file_extension="mp4")
        highest_res_stream = streams.get_highest_resolution()
        # Download the video
        save_path = os.path.join(os.getcwd(), yt.title + '.mp4')
        highest_res_stream.download(output_path=os.getcwd(), filename=yt.title)
        # Move the downloaded file to the default download folder
        default_download_folder = get_default_download_folder()
        shutil.move(save_path, os.path.join(default_download_folder, yt.title + '.mp4'))
        st.success("Video downloaded successfully!")
    except Exception as e:
        st.error(f"An error occurred: {e}")

def main():
    st.title("YouTube Video Downloader")
    
    # Input field for entering YouTube URL
    video_url = st.text_input("Enter YouTube URL:")
    
    # Button to trigger the download
    if st.button("Download"):
        if video_url.strip() == "":
            st.warning("Please enter a valid YouTube URL.")
        else:
            # Download the video and move it to the default download folder
            download_video(video_url)

if __name__ == "__main__":
    main()