dl_yt_playlist.sh

#!/bin/bash
#set -x
#
# Usage: ./dl_yt_playlist.sh "https://<youtube_playlist>" [<folder>]
# By default downloads highest quality audio to current dir
#
# IMPORTANT: Must use quotes on the commandline, the URI contains &!
#
# IMPORTANT: Expects a dedicated directory for the playlist
# You can specify a nonexistant directory and it will create one
# However, if you specify an existing dir, it will rename the files
# within.
#
# Dependencies: the `youtube-dl` command in $PATH
#
TO_DIR="${2:-.}"
red="$(tput setaf 1)"
bold="$(tput bold)"
normal="$(tput sgr0)"
seconds=30

declare -a FROM_ARRAY TO_ARRAY

cdDir() {
	cd "${1}" || { echo "Error: ${1} is not a dir, exiting." >&2; exit 1; }
}

renameYtFiles() {
	for i in "${!FROM_ARRAY[@]}"; do
		mv "${FROM_ARRAY[i]}" "${TO_ARRAY[i]}"
	done
}

mkFullDirPath() {
	echo "Creating dir: ${1}"
	mkdir -p "${1}" || { echo "Error: error creating dir ${1}" >&2 ; exit 1; }
}

nameFilter() {
	sed -r	-e 's/-[a-Z0-9]{10,11}\.(m4a|opus)$/\.\1/' \
		-e 's/ (\[|\().*(\]|\))//g' \
		-e 's/'\''//g' \
		-e 's/|//g' \
		-e 's/,//g' \
		-e 's/_/ /g' \
		-e 's/(([a-Z])|[ ])[-_] /\2 - /g' \
		<<< "${1}"
}

if [[ -e ${TO_DIR} ]]; then
	cdDir "${TO_DIR}"
else
	mkFullDirPath "${TO_DIR}"
	cdDir "${TO_DIR}"
fi

# --restrict-filenames actually makes it harder to remove brakcets
# -x is what extracts the audio, if you want video remove this.
youtube-dl -iwx --yes-playlist "${1}" | grep '^\[download\]'

while read -rd '' line; do
	FROM_DIR="${line%/*}" # get path
	FROM_DIR="${FROM_DIR/./}"
	FROM_NAME="${line##*/}" # get basename
	TO_NAME="$(nameFilter "${FROM_NAME}")"
	FROM_ARRAY+=("${FROM_DIR}${FROM_NAME}")
	TO_ARRAY+=("${FROM_DIR}${TO_NAME}")
done < <( find . -mindepth 1 -type f ! -name "$0" -print0 )

 column -t -s'|' <(
	for i in "${!FROM_ARRAY[@]}"; do
		echo "${FROM_ARRAY[i]}|${TO_ARRAY[i]}"
	done
	)

for (( i=seconds; i>0; i-- )); do
	echo -ne "${bold}Ok to rename? Will contine in" \
		" [${red}${i}${normal}${bold}] seconds [Y/n]:${normal} \033[K\r"
	sleep 1
done &
loop_pid="$!"

read -t"$seconds" -rsN1 answer </dev/tty
kill "$loop_pid" &>/dev/null
echo

case $answer in
	[Yy]|'') echo "Renaming files."; renameYtFiles ;;
	*)	echo "User cancelled the operation." >&2 ; exit 1 ;;
esac