Command Line Audio Playlist

clap.sh

#!/bin/bash

# Requirements: dialog mpv
# Optional: youtube-dl wget hq
# Arguments: none
#
# Changelog:
# > + from function to standalone script
#   + menu stack for saving previous menu command
#   + choices stack for saving previous menu choice
#   + "require" function
#   + "niceinfo" function
#   + back to menu on player close
#   + autofetch for http://musicforprogramming.net
#   + automatic requirements check
#
# > + dialog menu entries via associative array
#   + key array support for keeping custom order
#   + nice "addentry" function
#   + selection title shows up before playing
#   + internal functions unsetting before close


declare next back out err keys label defitem
declare stackmenu=("quit c") stackchoice=(-)
declare -A options


clearOptions() {
    keys=()
    options=()
}
addentry() {
    keys+=("${1:?Missing key}")
    options["$1"]="$2"
}
print() {
    printf '%b\n' "${@}"
}
niceinfo() {
    local text="${1:?Missing info text.}"
    if [[ "${text: -1}" != $'\n' ]]; then
        text+=$'\n'
    fi
    if ! which dialog &>/dev/null; then
        echo "$text"
        return
    fi
    local width height
    IFS=' ' read -r height width <<< $(wc -l -L <<< "$text")
    dialog --infobox "$text" $((height+1)) $((width+4))
}
nicemenu() {
    local oldnext="$next"
    next="${1:?Missing next cmd}"
    back="$3"
    local title="$2"
    shift 3
    local list=()
    for k in "${keys[@]}"; do
        list+=("$k" "${options[$k]}")
    done
    out=$(dialog ${defitem:+--default-item "$defitem"} --menu "$title" 0 0 0 "${list[@]}" 3>&2 2>&1 1>&3)
    local err=$?
    defitem=""
    if let "${#out} == 0"; then
        err=1
    fi
    if let "!err"; then
        stackmenu+=("$oldnext")
        stackchoice+=("$out")
        label="${options[$out]}"
    fi
    clearOptions
    next="${next} '$out'"
    return $err
}
require() {
    local notfound=()
    for pkg in "$@"; do
        if ! which "$pkg" &>/dev/null; then
            notfound+=("$pkg")
        fi
    done
    if let "${#notfound[@]} > 0"; then
        local msg="Unable to find these required executables:"
        local wait=0
        for missing in "${notfound[@]}"; do
            msg+=$'\n'" - $missing"
            let 'wait++'
        done
        niceinfo "$msg"
        sleep "$wait.7"
        return 1
    fi
    return 0
}


mmenu() {
    addentry ytvideo "Youtube"
    addentry mfp     "musicforprogramming.net"
    addentry direct  "Direct links"
    nicemenu 'eval' "Select source"
}
ytvideo() {
    if ! require youtube-dl; then return 1; fi
    addentry nxWxC0DffG8 "Power Outage During Thunderstorm ASMR Ambience"
    addentry mlQmCfjXApM "Mario Kart Wii - Main Menu Medley (Extended)"
    addentry ebhoaxFyDuM "Relaxation music 12 hours - Vol 3"
    addentry zT_zEAVFrNo "Study and DayDream #1 | Retrowave - Synthwave - Chillwave Mix 2019"
    addentry j5edzGidnPA "Best of Relaxing Synthwave Mix"
    nicemenu 'play yt' "Select video"
}

mfp_error() {
    niceinfo "Unable to fetch website content."
    sleep 1.7
    return 1
}
mfp() {
    if ! require hq wget; then return 1; fi
    niceinfo "Fetching website content..."
    local page=$(mktemp)
    if ! wget -q -O "$page" https://musicforprogramming.net/?about &>/dev/null; then
        mfp_error
        rm -f "$page"
        return
    fi
    while read -r entry; do
        IFS=$'\t' read -r url title <<< "$entry"
        addentry "$url" "$title"
    done <<< "$(paste \
        <(hq -f "$page" '#episodes > a' attr href) \
        <(hq -f "$page" '#episodes > a' text) \
        | tac
    )"
    rm -f "$page"
    nicemenu 'mfp_entry' "musicforprogramming.net"
}
mfp_entry() {
    niceinfo "Fetching website content..."
    local page=$(mktemp)
    if ! wget -q -O "$page" \
        "https://musicforprogramming.net/${1:?Missing url part.}" \
        &>/dev/null; then
        mfp_error
        rm -f "$page"
        return
    fi
    local url
    url=$(hq -f "$page" '#player' attr src)
    next="play - ${url@Q}"
    rm -f "$page"
}

direct() {
    addentry http://radio.plaza.one/opus_64 "Plaza One"
    nicemenu 'play -' "Select link"
}


play() {
    clear
    print "\e[1mTitle: \e[36m$label\e[0m"
    echo "(Please wait)"
    local args=()
    case "$1" in
        yt) args+=(
            "--ytdl-format=bestaudio[ext=m4a]/best[ext=mp4]/best"
            "https://www.youtube.com/watch?v=$2"
            );;
        *) args+=("$2")
    esac
    mpv --no-video --hwdec=yes --volume=50 "${args[@]}"
    if let 'err'; then
        sleep 1.7
    fi
    return 1
}


quit() {
    ${1:+clear}
    exit
}
signal() { :; }


if ! require dialog mpv; then return 1; fi
trap signal SIGINT
next=mmenu
while true; do
    if ! eval "$next"; then
        if [[ "$back" != "" ]]; then
            next="$back"
        else
            next="${stackmenu[-1]}"
            defitem="${stackchoice[-1]}"
            unset stackmenu[-1]
            unset stackchoice[-1]
        fi
    fi
done