#!/bin/bash
function asdf(){
    mv "$1" "$1 (backup)"
    ffmpeg -i "$1 (backup)" -map 0 -map -0:a:1 -c copy "$1"
}

if (( $# >= 1 ));then
    export -f asdf
    echo "The second audio track will be removed from the following files:"
    find "$1" -iname *".mp4"
    echo "Continue? [ y / n ]"
    read qwer
    if [[ "$qwer" == "y"* ]] || [[ "$qwer" == "Y"* ]]; then
        find "$1" -iname *".mp4" -exec bash -c "asdf \"{}\"" \;
    else
        echo "Canceled."
    fi
else
    echo "Usage: $0 <Destroy All Humans! dir>"
    echo "This will find and remove the second audio track(the German track) from all videos in the given directory (Destroy All Humans!)."
    echo "A backup of each video will be made first and appended with \"(backup)\", in case something goes wrong."
    echo "You are free to delete the backups if everything is working just fine."
fi