Add kitty terminal support

prev/ueberzug.sh

@@ -3,5 +3,3 @@
 setup_fifo
 
 send_image "$f"
-
-exit 1

sh/clear.sh

@@ -1,3 +1,7 @@
 setup_fifo 1
 
-printf '{"action": "remove", "identifier": "preview"}\n' > "$fifo"
+if use_ueberzug; then
+	printf '{"action": "remove", "identifier": "preview"}\n' > "$fifo"
+elif use_kitty; then
+	kitty +kitten icat --clear --transfer-mode file
+fi

sh/end.sh

@@ -1,4 +1,4 @@
 setup_fifo 1
 
 # tell ctpv server to exit
-printf '\0' > "$fifo"
+use_ueberzug && printf '\0' > "$fifo"

sh/helpers.sh

@@ -2,6 +2,19 @@ echo_err() {
 	echo "$@" >&2
 }
 
+is_kitty() {
+	[ -n "$KITTY_PID" ]
+}
+
+use_ueberzug() {
+	exists ueberzug
+}
+
+use_kitty() {
+	use_ueberzug && return 1
+	is_kitty
+}
+
 fifo_open() {
 	# https://unix.stackexchange.com/a/522940/183147
 	dd oflag=nonblock conv=notrunc,nocreat count=0 of="$1" \
@@ -9,6 +22,8 @@ fifo_open() {
 }
 
 setup_fifo() {
+	use_ueberzug || return 1
+
 	exit_code="${1:-127}"
 	[ -n "$fifo" ] || exit "$exit_code"
 	[ -e "$fifo" ] || exit "$exit_code"
@@ -24,9 +39,17 @@ check_exists() {
 }
 
 send_image() {
-	path="$(printf '%s' "$1" | sed 's/\\/\\\\/g; s/"/\\"/g')"
-	printf '{ "action": "add", "identifier": "preview", "x": %d, "y": %d, "width": %d, "height": %d, "scaler": "contain", "scaling_position_x": 0.5, "scaling_position_y": 0.5, "path": "%s"}\n' "$x" "$y" "$w" "$h" "$path" > "$fifo"
-	return 1
+	if use_kitty; then
+		kitty +kitten icat --transfer-mode file --align left \
+			--place "${w}x${h}@${x}x${y}" "$1"
+		return 1
+	elif use_ueberzug; then
+		path="$(printf '%s' "$1" | sed 's/\\/\\\\/g; s/"/\\"/g')"
+		printf '{ "action": "add", "identifier": "preview", "x": %d, "y": %d, "width": %d, "height": %d, "scaler": "contain", "scaling_position_x": 0.5, "scaling_position_y": 0.5, "path": "%s"}\n' "$x" "$y" "$w" "$h" "$path" > "$fifo"
+		return 1
+	else
+		return 127
+	fi
 }
 
 convert_and_show_image() {