#!/usr/bin/env bash
#<
# Download chant recordings from the monks of Le Barroux Abbey. With no date or
# hours given, download all the available hours for today. Files are named
# 'YYYY-MM-DD-${hourname}.mp3', where '${hourname}' is 'lauds', 'prime',
# 'terce', 'sext', 'none', 'vespers', or 'compline'.
#
# Usage: barroux [-d <outdir>] [<spec>...]
#        barroux -h
#
# Arguments:
#   <spec>
#       A combination of an optional date in YYMMDD format and optional hours
#       given by the first letter of their lowercased names. So '211231ptsn'
#       would indicate Prime, Terce, Sext, and None for December 31, 2021;
#       '220417' would indicate all the hours for April 17, 2022; and 'l' would
#       indicate Lauds for today.
#
# Options:
#   -d <outdir>
#       Save recordings in <outdir> instead of in the current directory.
#
# Commands:
#   -h
#       Show this help.
#
# Version: 1.0.0 (2025).
# Written by Renee Margaret McConahy.
#>

declare -r BASE=https://cdn.barrouxchant.com

declare tmp=""

quit() {
    local r=$?
    trap "" INT QUIT TERM HUP PIPE USR1 USR2
    trap - EXIT
    [[ -n ${1-} ]] && printf "%s\\n" "$1" >&2
    [[ -n $tmp ]] && rm -f -- "$tmp"
    if [[ -n ${1-} ]]; then exit 1; else exit $r; fi
}

trap quit EXIT
trap 'quit "Uncaught error at $(basename -- "$0"):$LINENO"' ERR
set -Euo pipefail

declare outdir=.

while getopts d:h opt; do
    case $opt in
    d) outdir=$OPTARG ;;
    h|*)
        sed -ne '/^#</,/^#>/ { /^#\(<\|>\)/d; s/^# \?//; p; }' -- "$0"
        [[ $opt == "?" ]] && exit 1
        exit 0 ;;
    esac
done
shift $((OPTIND - 1))

[[ -d $outdir ]] || quit "No such directory: ${outdir@Q}."

# By default, download all the hours for today.
((!$#)) && set ""

for spec; do
    if [[ ! $spec =~ ^(([0-9]{2})([0-9]{2})([0-9]{2}))?([l|p|t|s|n|v|c]*)$ ]]
    then
        echo "Bad arg."
        continue
    fi

    if [[ -n ${BASH_REMATCH[1]} ]]; then
        date=20${BASH_REMATCH[2]}-${BASH_REMATCH[3]}-${BASH_REMATCH[4]}
    else
        date=$(date +%Y-%m-%d)
    fi

    hours=${BASH_REMATCH[5]:-lptsnvc}

    for ((i = 0; i < ${#hours}; i++)); do
        case ${hours:i:1} in
        l) hourname=lauds ;;
        p) hourname=prime ;;
        t) hourname=terce ;;
        s) hourname=sext ;;
        n) hourname=none ;;
        v) hourname=vespers ;;
        c) hourname=compline ;;
        *) quit "Internal error at line $LINENO"
        esac

        file=$date-$hourname.mp3

        if [[ -f $outdir/$file ]]; then
            echo "Already have $file."
            continue
        fi

        echo "Getting $file..."

        tmp=$(mktemp)
        if curl --disable -L --fail --progress-bar -o "$tmp" "$BASE/$file"; then
            mv -- "$tmp" "$outdir/$file"
        else
            rm -f -- "$tmp"
        fi
        tmp=""
    done
done