#!/bin/sh

# Get webring links to append to the CSV before building

# Some webrings require an iframe or scripts, but I want a plain static
# first-party HTML+CSS page. This script fetches webring links by
# parsing the iframes and appends appropriate values to my webrings.csv file.

#shellcheck disable=SC3040  # This only sets pipefail if it's available (e.g. in Bash, Zsh) and otherwise does nothing (in other POSIX shells like Busybox sh and dash)
set -o pipefail 2>/dev/null

set -e -u

# the name of this program
progname="$(basename "$0")"
dirname="$(dirname "$0")"

webrings_src="$dirname/../assets/csv/webrings.base.csv"
webrings_dest="$dirname/../assets/csv/webrings.csv"

help_text="Usage: $progname [OPTION...]

Update webrings.csv with new prev/next links, to avoid iframes/scripts

Options:
  -h            Print this help and exit
  -d            Dry run; just print results, don't update webrings.csv
"

usage() {
	printf '%s' "$help_text"
}

# when the user passess bad args, send a msg to stderr and exit
# usage: bad_option <option> <reason>
bad_option() {
	echo "$progname: option $1: $2" >&2
	usage >&2
	exit 1
}

dry_run='0'

while getopts "hd" flags; do
	case $flags in
		h)
			usage
			exit 0
			;;
		d)
			dry_run='1'
			shift
			;;
		*)
			bad_option "$flags" 'invalid option'
			;;
	esac
done

endless_orbit() {
	printf 'Endless Orbit,'
	curl -sSL --compressed https://linkyblog.neocities.org/onionring/onionring-variables.js \
		| grep -C 1 https://seirdy.one/ \
		| tr -d "'\n" | sed 's|https://seirdy.one/|https://linkyblog.neocities.org/webring.html|'
	echo 'null'
}

focus_first() {
	printf 'Focus First,'
	curl -sSL --compressed https://owlsroost.xyz/webring/onionring-variables.js \
		| grep -C 1 https://seirdy.one/ \
		| tr -d "'\r\n\t" | sed 's|https://seirdy.one/|https://owlsroost.xyz/webring/index.html|'
	echo 'null'
}

all_lines() {
	endless_orbit
	focus_first
}

if [ "$dry_run" = '1' ]; then
	all_lines
elif [ -f "$webrings_dest" ]; then
	echo "webrings file already generated"
else
	all_lines | cat "$webrings_src" - >"$webrings_dest"
fi

# vi:ft=sh