#! /bin/bash

print_help() {
echo "Usage: $(basename $0) INPUT... -o OUTPUT"
echo "   or: $(basename $0) INPUT... 3> OUTPUT"
echo "Merge INPUT(s) videos to single OUTPUT"
}

inputs=()
while [ "$#" -gt 0 ]; do
  case $1 in
  -h | --help)
	print_help
	exit 0
        ;;
  -o | --output)
	if [ "$2" != ' ' ]
	then
	    output=$2
	else
	    echo "$(basename $0): No output file after '-o'" >&2
	    echo "Try '$(basename $0) --help' for more information." >&2
	    exit -1
	fi
	shift; shift
	;;
  -i | --interactive)
	interactive="true"
	shift
	;;
  *)
	inputs=( "${inputs[@]}" "$1" )
	shift
	;;
  esac
done

while [ $interactive ]
do
    echo $interactive
    echo "$(basename $0): merging '${inputs[@]}' to '${output}'"
    echo "Do you want to continue? [Y/n] "
    read ans
    case $ans in
 	n | no)
	    exit 1
	    ;;
	y | yes | '')
	    echo "yes"
	    unset interactive
	    ;;
    esac
done

if [ -n "$output" ]
then
    mencoder -forceidx -ovc copy -oac copy "${inputs[@]}" -o "$output"
else
    echo "$(basename $0): No output arguments" >&2
    echo "Try '$(basename $0) --help' for more information." >&2
fi