1 files changed, 128 insertions, 0 deletions
diff --git a/src/remembering.in b/src/remembering.in
new file mode 100755
index 0000000..c89beef
--- /dev/null
+++ b/src/remembering.in
@@ -0,0 +1,128 @@
+#!/bin/sh
+set -eu
+
+usage() {
+	printf 'Usage:	%s -p PROFILE -c "COMMAND"\n' "$0"
+}
+
+help() {
+	echo '
+Options:
+ -p      profile to be used for gathering and storing data
+ -c      command to be run, reading from STDIN, writing to STDOUT
+ -h      show this help
+ -V      print program version
+
+See manpages for more information.'
+}
+
+missing() {
+	printf 'Missing option: %s\n' "$1" >&2
+}
+
+# shellcheck disable=2068
+for flag in $@; do
+	if [ "$flag" = '--help' ]; then
+		usage
+		help
+		exit 0
+	fi
+done
+
+COMMANDFLAG=
+PROFILEFLAG=
+while getopts 'hc:p:V' name; do
+	case "$name" in
+		c)
+			COMMANDFLAG="$OPTARG"
+			;;
+		p)
+			PROFILEFLAG="$OPTARG"
+			;;
+		h)
+			usage
+			help
+			exit
+			;;
+		V)
+			echo 'remembering-@VERSION@ @DATE@'
+			exit
+			;;
+		*)
+			echo "Ignoring unrecognized flag '$name'" >&2
+			;;
+	esac
+done
+
+if [ -z "$COMMANDFLAG" ]; then
+	missing '-c "COMMAND"'
+	usage >&2
+	exit 2
+fi
+
+if [ -z "$PROFILEFLAG" ]; then
+	missing '-p PROFILE'
+	usage >&2
+	exit 2
+fi
+
+COMMAND="$COMMANDFLAG"
+PROFILE="${XDG_DATA_HOME:-$HOME/.local/share/remembering}/$PROFILEFLAG"
+
+if [ ! -e "$PROFILE" ]; then
+	mkdir -p "$(dirname "$PROFILE")"
+	touch "$PROFILE"
+fi
+
+MERGED="$(mktemp)"
+FILTERED="$(mktemp)"
+SORTED_STDIN="$(mktemp)"
+cat - > "$SORTED_STDIN"
+
+# sed line to reverse lines, replacing GNU/Linux's tac
+# Taken from:
+# https://unix.stackexchange.com/questions/280685/reverse-sequence-of-a-file-with-posix-tools/280686#comment601716_280686
+xargs -I{} printf '0:%s\n' "{}" < "$SORTED_STDIN" | \
+	sort -t: -k2,2 -m - "$PROFILE" | \
+	sed '1!x;H;1h;$!d;g' | \
+	sort -t: -k2,2 -u > "$MERGED"
+
+xargs -I{} printf 'filter_marker:%s\n' "{}" < "$SORTED_STDIN" | \
+	cat - "$PROFILE" | \
+	sort -t: -k2,2 | \
+	awk '{
+		split($0, l, ":")
+		rank = l[1]
+		entry = substr($0, length(rank) + 2)
+		if (rank != "filter_marker") {
+			prev_rank = rank
+			prev_entry = entry
+		} else {
+			if (prev_entry == entry) {
+				print prev_rank ":" entry
+			} else {
+				print "0:" entry
+			}
+		}
+	}' > "$FILTERED"
+
+CHOICE="$(sort -t: -k1nr,1 -k2,2 < "$FILTERED" | \
+	cut -d: -f2- | \
+	sh -c "$COMMAND")"
+
+if [ -n "$CHOICE" ]; then
+	NEW_PROFILE="$(mktemp)"
+	awk -v choice="$CHOICE" '{
+		split($0, l, ":")
+		rank = l[1]
+		entry = substr($0, length(rank) + 2)
+		if (entry == choice) {
+			# Naively increment ranking by one
+			print rank + 1 ":" entry
+		} else {
+			print rank ":" entry
+		}
+	}' "$MERGED" > "$NEW_PROFILE"
+	mv "$NEW_PROFILE" "$PROFILE"
+	echo "$CHOICE"
+fi