Add -R and -I args; use getopts

Adds -R (no responses) and -I (reverse-order)
parameters, thanks to the use of getopts
(rather than just getting $1 etc.)

fedi2html.sh

@@ -73,7 +73,9 @@ render_post() {
 	local POST_DATE="$(echo "$post_data"      | jq -r .created_at)"
 	local POST_CONTENT="$(echo "$post_data"   | jq -r .content | replace_emojis "$post_data")"
 	local POST_ATTACHMENTS="$(media_attachments "$post_data")"
-	local POST_RESPONSES="$(render_responses "$post_data" "$responses_data" "$POST_TREE_LEVEL")"
+	if test -z "$NO_RESPONSES"; then
+		local POST_RESPONSES="$(render_responses "$post_data" "$responses_data" "$POST_TREE_LEVEL")"
+	fi
 	env_subst "$POST_TEMPLATE"
 }
 
@@ -150,7 +152,7 @@ media_attachments() {
 context_to_responses() {
 	jq '.descendants' \
 		| jq 'sort_by(.created_at)' \
-		| jq 'reverse' \
+		| maybe_jq_reverse \
 		| jq -cr '.[]'
 }
 
@@ -238,8 +240,23 @@ env_subst() {
 }
 
 
+# Based on the environment variable $REVERSE_ORDER (whether or not user provided
+# the -I flag), reverse the JSON array over stdin.
+# This is used to enable/disable reverse-chronological order of posts.
+#     fetch_context $url | jq '.descendants' | maybe_jq_reverse
+maybe_jq_reverse() {
+	local input="$(cat)"
+	if test -n "$REVERSE_ORDER"; then
+		echo "$input" \
+			| jq 'reverse'
+	else
+		echo "$input"
+	fi
+}
+
+
 usage() {
-	echo "usage: $(basename "$0") POST_URL"
+	echo "usage: $(basename "$0") [-h] [-IR] POST_URL"
 	echo
 	echo "$(basename "$0") does exactly what it says on the tin: It formats"
 	echo "a fediverse post (and its replies) into simple-and-embeddable HTML."
@@ -251,17 +268,35 @@ usage() {
 	echo "that images are all fetched from remote sources. It is recommended,"
 	echo "if privacy or total archival, is a concern, to use wget(1)’s --mirror"
 	echo "(or something like it) to fetch even these foreign files."
+	echo
+	echo "  -h             print this message and exit"
+	echo "  -I             display posts in reverse-chronological order"
+	echo "  -R             do not recursively display posts’ responses"
 }
 
 
+while getopts 'hRI' arg; do
+	case $arg in
+		h)
+			usage
+			exit 0
+			;;
+		I)
+			REVERSE_ORDER="1"
+			;;
+		R)
+			NO_RESPONSES="1"
+			;;
+	esac
+done
+
+shift $((OPTIND-1))
+
 URL="$1"
 
 if test -z "$URL"; then
 	usage 1>&2
 	exit 2
-elif test "$URL" = "-h" -o "$URL" = "--help"; then
-	usage
-	exit 0
 fi