xrated

#!/bin/sh
#########################################################################
# Made by    : Ewoud Dronkert
# Licence    : GNU GPL v3
# Platform   : macOS, Linux
# Requires   : sh, date, curl, touch, open
# Location   : ~/bin, /usr/local/bin
# Name       : xrated
# Version    : 1.0.0
# Date       : 2018-12-14
# Purpose    : Download episodes of radio show "X-Rated"
#            :   from Concertzender, formerly KinkFM
# Parameters : [number of recent episodes to download] default=1
# Settings   : DIR = folder with downloaded files
#            : PRE = filename prefix for downloaded files
# Exit     0 : No script errors
#          1 : Folder not found and could not be created
#          2 : Invalid parameter, number of episodes must be >=1, <1000
#          3 : Weekday number not correctly determined
#########################################################################

# Where to keep downloaded files, check if folder exists
DIR=~/Music/KinkFM
[ ! -d "$DIR" ] && mkdir -p "$DIR" 2>/dev/null
if [ ! -d "$DIR" ]; then
	echo "Folder not found: $DIR" >&2
	exit 1
fi

# Optional parameter: number of recent episodes to download
# default = 1
declare -i WEEKS=1
if [ -n "$1" ]; then
	if [ "$1" -ge 1 -a "$1" -lt 1000 ]; then
		WEEKS="$1"
	else
		echo 'Number of episodes should be in [1..1000>.' >&2
		exit 2
	fi
fi

# Weekday number of today, Monday=1 .. Sunday=7
declare -i AGO=$(date '+%u' 2>/dev/null)
if [ $AGO -lt 1 -o $AGO -gt 7 ]; then
	echo 'Internal error: weekday should be in [1..7].' >&2
	exit 3
fi

BASE='https://streams.greenhost.nl/cz/cz/rod'
TIME='2100'
PRE='X-Rated_'
EXT='mp3'

# Loop WEEKS times, each time look for the episode from a week earlier
while [ "$WEEKS" -gt 0 ]
do
	# Get date in YYYYMMDD format for AGO days ago, try BSD and GNU style
	DATE="$(date -v-${AGO}d +%Y%m%d 2>/dev/null || date --date="${AGO} days ago" +%Y%m%d)"
	# Local filename
	FILE="$PRE$DATE.$EXT"
	# Local path
	DEST="$DIR/$FILE"
	# Check if file exists, if not try to download
	if [ -e "$DEST" ]; then
		echo "Found: $FILE"
	else
		echo "Downloading: $FILE"
		# Download to file, use progress bar, preserve file time
		curl -# "$BASE/$DATE-$TIME.$EXT" -R -o "$DEST"
		# Just to be sure, check file modification time
		if [ -e "$DEST" ]; then
			TREF="${DATE}2300.00"
			TMOD="$(date -r "$DEST" +%Y%m%d%H%M.%S)"
			[ "$TREF" != "$TMOD" ] && touch -t "$TREF" "$DEST"
		fi
	fi
	# Next loop: look 7 days further back
	AGO=$((AGO + 7))
	# Loop counter
	WEEKS=$((WEEKS - 1))
done

# If on Mac, open the folder with downloaded episodes
[ "$(uname)" = "Darwin" ] && open "$DIR"

exit 0