Add album art, artist, and album to all MP3s in the current folder.

metadata.sh

#!/bin/bash

FCLR="\e[0m"
FBLD="\e[1m"
FRED="\e[31m"
FYEL="\e[33m"
FWHT="\e[39m"

###########################################################################################
#### SCRIPT CREATED: 2021-07-11                                                           #
#### AUTHOR: toydotgame                                                                   #
#### Metadata script V2. Takes `--debug` argument. Assumes directory at ~/Music/, with    #
#### ~/Music/Album Covers/ as art directory and an /Artist/Album/Song.ext file structure. #
#### Requires: curl, ffmpeg, yt-dlp                                                       #
###########################################################################################

# Init:
if [[ $1 = "--debug" ]]; then printf "$FBLD${FYEL}[Debug]$FWHT Beginning init...$FCLR\n"; fi

alias ffmpeg="ffmpeg -hide_banner -loglevel error"
if [[ $1 = "--debug" ]]; then
	alias ffmpeg="ffmpeg -hide_banner"
fi

if [[ ! -d "/tmp/metadatash/" ]]; then
	mkdir "/tmp/metadatash/"
else # Lazy not doing a check if files even exist in here because I'm not bothered to write a condition
	rm -rf /tmp/metadatash/*
fi

if [[ ! -d "$HOME/Music/Album Covers/" ]]; then
	mkdir -p "$HOME/Music/Album Covers/"
fi

USRRES= # User response
ARTLOC= # Location of album art (const)
ARTIST= # Metadata artist (const)
FSARTS= # UNIX FS-safe artist (const)
ALBUM=  # Album name (const)
FSALBM= # UNIX FS-safe album (const)
TRCKNM= # UNIX FS-safe filename

RespToLower () {
	USRRES=$(printf "$USRRES" | tr "[:upper:]" "[:lower:]")
}

if [[ $1 = "--debug" ]]; then printf "$FBLD${FYEL}[Debug]$FWHT Init complete. Press any key to continue.$FCLR"; read; fi

# Song downloader:
if [[ $1 = "--debug" ]]; then printf "$FBLD${FYEL}[Debug]$FWHT Beginning song download...$FCLR\n"; fi

printf "Is this album/song downloaded? [y/N]: "; read USRRES
RespToLower
if [[ "$USRRES" != "y" ]]; then
	printf "What is the URL of the song/playlist?: "; read USRRES
	if [[ -z "$USRRES" ]]; then
		printf "$FBLD${FRED}[Error]$FWHT No URL supplied! Exiting.$FCLR\n"
		exit
	fi
	cd "/tmp/metadatash/"
	yt-dlp -q --progress -x --audio-format mp3 -o "%(title)s.%(ext)s" "$USRRES"
else
	printf "Which directory holds the album/What path is the song at? (Must be relative to / or ~): "; read USRRES
	if [[ -z "$USRRES" ]]; then
		printf "$FBLD${FRED}[Error]$FWHT No path supplied! Exiting.$FCLR\n"
		exit
	fi
	USRRES="${USRRES/#\~/$HOME}"
	if [[ -d "$USRRES" ]]; then
		cd "$USRRES"
		for f in *; do
			ffmpeg -i "$f" "/tmp/metadatash/${f%.*}.mp3"
		done
	elif [[ -f "$USRRES" ]]; then
		ffmpeg -i "$USRRES" "/tmp/metadatash/$(basename "${USRRES%.*}").mp3"
	else
		printf "$FBLD${FRED}[Error]$FWHT Path does not exist or is not valid! Exiting.$FCLR\n"
		exit
	fi
fi

if [[ $1 = "--debug" ]]; then printf "$FBLD${FYEL}[Debug]$FWHT Song download complete. Press any key to continue.$FCLR"; read; fi

# Art:
if [[ $1 = "--debug" ]]; then printf "$FBLD${FYEL}[Debug]$FWHT Beginning art assignment...$FCLR\n"; fi

cd "/tmp/metadatash/"
printf "Where is the album art stored? (Can be a URL or file relative to / or ~): "; read USRRES
if [[ ! -z  "$USRRES" ]]; then
	if [[ "$USRRES" == http* ]]; then # URL location
		curl -o "cover" "$USRRES"
		ffmpeg -i "cover" "cover.png" && rm -f "cover"
	else
		USRRES="${USRRES/#\~/$HOME}"
		ffmpeg -i "$USRRES" "cover.png" && rm -f "$USRRES"
	fi
	
	printf "What do you want to call the album art image file? (Will be a PNG): "; read USRRES
	if [[ ! -z "$USRRES" ]]; then
		mv "cover.png" "$HOME/Music/Album Covers/$USRRES.png"
		ARTLOC="$HOME/Music/Album Covers/$USRRES.png"
		for f in *; do
			ffmpeg -i "$f" -i "$ARTLOC" -c copy -map 0 -map 1 -metadata:s:v title="Album cover" -metadata:s:v comment="Cover (front)" "${f%.*}-m0.mp3" && rm -f "$f"
		done
	fi
else
	for f in *; do
		mv "$f" "${f%.*}-m0.mp3"
	done
fi

if [[ $1 = "--debug" ]]; then printf "$FBLD${FYEL}[Debug]$FWHT Art assignment complete. Press any key to continue.$FCLR"; read; fi

# Metadata editor:
if [[ $1 = "--debug" ]]; then printf "$FBLD${FYEL}[Debug]$FWHT Beginning metadata assignment...$FCLR\n"; fi

printf "Who is the artist?: "; read USRRES
if [[ -z "$USRRES" ]]; then
	ARTIST="Unknown artist"
else
	ARTIST="$USRRES"
	if [[ "$ARTIST" == *"/"* ]]; then
		FSARTS="${ARTIST//\//}" # Remove all slashes
		if [[ -z "$FSARTS" ]]; then
			FSARTS="Unknown artist"
		fi
	else
		FSARTS="$ARTIST"
	fi
fi

printf "What is name of the album?: "; read USRRES
if [[ -z "$USRRES" ]]; then
	ALBUM="Unknown album"
else
	ALBUM="$USRRES"
	if [[ "$ALBUM" == *"/"* ]]; then
		FSALBM="${ALBUM//\//}" # Remove all slashes
		if [[ -z "$FSALBM" ]]; then
			FSALBM="Unknown artist"
		fi
	else
		FSALBM="$ALBUM"
	fi
fi
if [[ ! -d "$HOME/Music/$FSARTS/$FSALBM/" ]]; then
	mkdir -p "$HOME/Music/$FSARTS/$FSALBM/"
fi

for f in *; do
	ffmpeg -i "$f" -c copy -metadata artist="$ARTIST" -metadata album="$ALBUM" "${f%.*},1.mp3" && rm -f "$f"
done

for f in *; do
	printf "What is the track name of \"${f%-m0*}\"?: "; read USRRES
	if [[ -z "$USRRES" ]]; then
		USRRES="${f%-m0*}"
	fi
	if [[ "$USRRES" == *"/"* ]]; then
		TRCKNM="${USRRES//\//}"
		if [[ -z "$TRCKNM" ]]; then
			TRCKNM="$(date +%N)" # Effectively random 9 digits
		fi
	else
		TRCKNM="$USRRES"
	fi
	ffmpeg -i "$f" -c copy -metadata title="$USRRES" "${f%.*},2.mp3" && rm -f "$f"

	printf "What is the track number of \"$USRRES\"?: "; read USRRES
	if [[ "$USRRES" =~ ^[0-9]+$ ]]; then
		ffmpeg -i "${f%.*},2.mp3" -c copy -metadata track="$USRRES" "$HOME/Music/$FSARTS/$FSALBM/$TRCKNM.mp3" && rm -f "${f%.*},2.mp3"
	else
		if [[ $1 = "--debug" ]]; then printf "$FBLD${FRED}[Error]$FWHT Track number \$USRRES=\"$USRRES\", NaN error! Setting to null.$FCLR\n"; fi
		mv "${f%.*},2.mp3" "$HOME/Music/$FSARTS/$FSALBM/$TRCKNM.mp3"
	fi
done

if [[ $1 = "--debug" ]]; then printf "$FBLD${FYEL}[Debug]$FWHT Metadata assignment complete. Press any key to continue.$FCLR"; read; fi

# Clean up:
if [[ $1 = "--debug" ]]; then printf "$FBLD${FYEL}[Debug]$FWHT Beginning cleanup...$FCLR\n"; fi

rm -rf "/tmp/metadatash/"

if [[ $1 = "--debug" ]]; then printf "$FBLD${FYEL}[Debug]$FWHT Cleanup complete. Press any key to continue.$FCLR"; read; fi

// TODO: Download `-f 251` copies of `--audio-format mp3` using `youtube-dl` (obviously note dependency in script description) function, to take a playlist or video URL and work with that. Maybe even create a child working directory.

LOL! Done! V2 out and it downloads stuff! #GetRekt 2022 me!