From 0565fb8877ed206ae6a3e149072c1cbbb2fd9543 Mon Sep 17 00:00:00 2001
From: Case Duckworth
Date: Sun, 5 Mar 2023 10:58:09 -0600
Subject: Initial commit

twerk.first is the first writing, for posterity.
---
 twerk       | 237 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 twerk.first | 122 +++++++++++++++++++++++++++++++
 2 files changed, 359 insertions(+)
 create mode 100755 twerk
 create mode 100755 twerk.first

diff --git a/twerk b/twerk
new file mode 100755
index 0000000..2b0dfd7
--- /dev/null
+++ b/twerk
@@ -0,0 +1,237 @@
+#!/bin/sh
+## twerk: a twtxt client
+# by Case Duckworth
+
+### Entry point
+
+usage() {
+	cat >&2 <<EOF
+TWERK: a twtxt client
+usage: twerk [options] [file]
+
+twerk can be fed a list of URLs from standard input or from a FILE.
+Each line is expected to contain a URL of a twtxt feed and (optionally) the
+display name to use for that feed.
+
+options (default):
+ -h          Show this help and exit.
+ -t          Include the time in each post date.
+ -f          Force redownload of twt data.
+ -n LIMIT    Only show LIMIT posts (25).  0 means no limit.
+ -w WIDTH    Limit the output's width to WIDTH characters (72).
+ -W WIDTH    Limit the username's width to WIDTH characters (12).
+ -i INDENT   Use INDENT spaces as a hanging indent for too-long lines
+             ([calculated]).
+ -p COMMAND  Use COMMAND to post twts ([not set]).
+             This command will be fed a twtxt-formatted string via stdin.
+             Recommended: \`ssh <host> tee -a <file>\`.
+
+parameters:
+ FILE        List of twtxt feeds to fetch, one feed per line.
+             Optionally, a string after the feed URL will be its
+             display name.
+EOF
+	exit "${1:-0}"
+}
+
+configure() {
+	# defaults
+	TWERK_WIDTH="${TWERK_WIDTH:-72}"
+	TWERK_LIMIT="${TWERK_LIMIT:-25}"
+	TWERK_INCLUDE_TIME="${TWERK_INCLUDE_TIME:-0}"
+	TWERK_USER_WIDTH="${TWERK_USER_WIDTH:-12}"
+	TWERK_HANG="${TWERK_HANG:-}" # empty to calculate off other variables
+	TWERK_FORCE="${TWERK_FORCE:-false}"
+	TWERK_POST_COMMAND="${TWERK_POST_COMMAND:-:}" # no-op
+
+	while getopts htfn:w:W:i:p:c: opt
+	do
+		case "$opt" in
+			h) usage ;;
+			t) TWERK_INCLUDE_TIME=1 ;;
+			f) TWERK_FORCE=true ;;
+			n) TWERK_LIMIT="$OPTARG" ;;
+			w) TWERK_WIDTH="$OPTARG" ;;
+			W) TWERK_USER_WIDTH="$OPTARG" ;;
+			i) TWERK_HANG="$OPTARG" ;;
+			p) TWERK_POST_COMMAND="$OPTARG" ;;
+			c) TWERK_FEEDS="$OPTARG" ;;
+			*) usage 1 ;;
+		esac
+	done
+
+	if test -z "$TWERK_HANG"
+	then
+		TWERK_HANG=$((TWERK_USER_WIDTH+(TWERK_INCLUDE_TIME*6)+10+3))
+		echo >&2 "$TWERK_HANG"
+	fi
+}
+
+main() {
+	TWERK_CACHE="${XDG_CACHE_HOME:-$HOME/.cache}/twerk"
+	mkdir -p "$TWERK_CACHE"
+	TWERK_FILE="$TWERK_CACHE/:file:"
+
+	TWERK_LESSKEY="$TWERK_CACHE/:lesskey:"
+	lesskey_setup
+
+	if "$_TWERK_INITIAL"
+	then
+		configure "$@"
+		shift "$((OPTIND - 1))"
+		TWERK_FEEDS="$1"
+	fi
+
+	cat "$TWERK_FEEDS" |
+		fetch_posts |
+		sort_posts |
+		limit_posts "$TWERK_LIMIT" |
+		format_posts > "$TWERK_FILE"
+
+	read_posts "$TWERK_FILE"
+}
+
+### Library
+
+fetch_posts() {
+	while read -r url name
+	do
+		if test -z "$name"
+		then
+			file="$TWERK_CACHE/$(url_normalize "$name")"
+		else
+			file="$TWERK_CACHE/$name"
+		fi
+
+		if "$TWERK_FORCE" || test -z "$(find "$file" -prune -mtime -1 2>/dev/null)"
+		then
+			printf >&2 'Downloading %s...\n' "$url"
+			curl -sf "$url" |
+				filter_lines |
+				while read -r date post
+				do
+					printf '%s\t%s\t%s\t%s\n' \
+					       "$date" "$name" "$url" "$post"
+				done |
+				tee "$file"
+		else
+			cat "$file"
+		fi
+	done
+}
+
+url_normalize() {
+	printf '%s\n' "$1" | tr -d ':/~'
+}
+
+filter_lines() {
+	while read -r line
+	do
+		case "$line" in
+			\#*) ;;
+			'') ;;
+			*) printf '%s\n' "$line" ;;
+		esac
+	done
+}
+
+limit_posts() {
+	ln=0
+	while read -r line
+	do
+		if test "$1" -ne 0 && test "$ln" -gt "$1"
+		then
+			break
+		fi
+		printf '%s\n' "$line"
+		ln=$((ln+1))
+	done
+}
+
+sort_posts() {
+	sort -r
+}
+
+format_posts() {
+	while IFS='	' read -r date name url post
+	do
+		if test 0 -eq "$TWERK_INCLUDE_TIME"
+		then
+			TWERK_DATE_WIDTH=10
+			date="${date%T*}"
+		else
+			TWERK_DATE_WIDTH=16
+		fi
+
+		printf "%${TWERK_DATE_WIDTH}s | %${TWERK_USER_WIDTH}s | " \
+		       "$(echo "$date" | head -c$TWERK_DATE_WIDTH)" \
+		       "$(echo "$name" | head -c$TWERK_USER_WIDTH)"
+
+		export url name date post TWERK_WIDTH TWERK_HANG
+		export linewidth="$TWERK_HANG"
+
+		printf '%s\n' "$post" |
+			tr ' ' '\n' |
+			while IFS= read word
+			do
+				if test $(( linewidth + ${#word} )) -ge "$TWERK_WIDTH"
+				then
+					echo
+					linewidth=0
+					printf "%${TWERK_HANG}s \` " ""
+					linewidth=$((linewidth+TWERK_HANG+2))
+				fi
+				printf '%s ' "$word"
+				linewidth=$((linewidth + ${#word}))
+			done
+		echo
+	done
+}
+
+
+lesskey_setup() {
+	# t will exit with code 48
+	if ! test -r "$TWERK_LESSKEY"
+	then
+		lesskey -o "$TWERK_LESSKEY" - <<EOF
+#command
+t quit 0
+g quit 1
+#line-edit
+#env
+EOF
+	fi
+}
+
+read_posts() {
+	less \
+		-k "$TWERK_LESSKEY" \
+		-Pm'twerk! t\: twt, g\: refresh' -m \
+		"$1"
+
+	case "$?" in
+		0) exit ;;
+		48) post ;;
+		49) refresh ;;
+	esac
+}
+
+post() {
+	printf 'Twt: ' >&2
+	read -r post
+	echo >&2
+
+	post="$(printf '%s\t%s\n' "$(date +'%FT%T%z')" "$post")"
+
+	eval "printf '%s\n' \"\$post\" | $TWERK_POST_COMMAND"
+	_TWERK_INITIAL=false main "$TWERK_FEEDS"
+}
+
+refresh() {
+	TWERK_FORCE=true main "$TWERK_FEEDS"
+}
+
+###################################
+_TWERK_INITIAL=true
+test -z "$DEBUG" || set -x
+test -z "$SOURCE" && main "$@"
diff --git a/twerk.first b/twerk.first
new file mode 100755
index 0000000..9b43e3e
--- /dev/null
+++ b/twerk.first
@@ -0,0 +1,122 @@
+#!/bin/sh
+## twerk: a twtxt client in sh
+# by Case Duckworth
+
+### Entry point
+
+usage() {
+	cat >&2 <<EOF
+TWERK: a twtxt client
+usage: twerk [options] [file]
+
+options:
+ -h        show this help and quit
+ -t        include time in post date
+ -T        don't include time in post date (default)
+ -n NUMBER limit posts to NUMBER (100)
+ -w WIDTH  limit the width of the display (72)
+ -H WIDTH  define the hanging indent of twts
+ -u WIDTH  limit the width of the user display (12)
+EOF
+	exit "${1:-0}"
+}
+
+configure() {
+	TWERK_INCLUDE_TIME=0
+	TWERK_WIDTH="${COLUMNS:-72}"
+	TWERK_USER_WIDTH=12
+	while getopts hn:w:H:t opt; do
+		case "$opt" in
+			h) usage ;;
+			n) TWERK_N="$OPTARG" ;;
+			w) TWERK_WIDTH="$OPTARG" ;;
+			H) TWERK_HANG="$OPTARG" ;;
+			u) TWERK_USER_WIDTH="$OPTARG" ;;
+			t) TWERK_INCLUDE_TIME=1 ;;
+			T) TWERK_INCLUDE_TIME=0 ;;
+			*) usage 1 ;;
+		esac
+	done
+	if test -z "$TWERK_HANG"; then
+		TWERK_HANG=$((TWERK_USER_WIDTH+(TWERK_INCLUDE_TIME*6)+10+3))
+	fi
+
+}
+
+main() {
+	configure "$@"; shift "$((OPTIND - 1))"
+	cat "${@:--}" |
+		curl_from_file
+}
+
+### Library
+
+curl_from_file() {
+	while read -r url name; do
+		curl -sf "$url" |
+			filter_posts |
+			awk -v url="$url" -v name="$name" \
+			    '{ printf "%s\t%s\t%s\n", name, url, $0; }'
+	done |
+		sort_posts |
+		format_posts
+}
+
+filter_posts() {
+	filter_comments | limit_posts "${TWERK_N:-100}"
+}
+
+filter_comments() {
+	awk '/^[ \t]*#/{next;}/^$/{next;}{print;}'
+}
+
+limit_posts() {
+	head -n "$1"
+}
+
+
+sort_posts() {
+	sort -r
+}
+
+format_posts() {
+	awk \
+	    -v UW="$TWERK_USER_WIDTH" \
+	    -v IT="$TWERK_INCLUDE_TIME" \
+	    -v WIDTH="$TWERK_WIDTH" \
+	    -v HANG="$TWERK_HANG" \
+	    'BEGIN {FS="\t";}
+!IT { sub(/T.*$/, "", $3); }
+IT {
+    sub(/+.*$/, "", $3);
+    sub(/T/, " ", $3);
+    sub(/:..$/,"",$3);
+}
+
+{ printf("%s | %" UW "s | ", $3, substr($1,1,UW-1)); }
+
+# wrap lines
+{
+    w = HANG # width
+    ls = 0 # lines
+    split($2, words, /[ \t]/)
+    for (i=1; i<=length(words); i++) {
+	if (w+length(words[i]) >= WIDTH) {
+	    print ""
+	    w = 0
+	    if (++ls) {
+	        printf "%" HANG "s ` ", ""
+		w += HANG + 2
+	    }
+	}
+	printf "%s ", words[i]
+	w += length(words[i])
+    }
+    print ""
+}
+'
+}
+
+###
+test -z "$DEBUG" || set -x
+test -z "$SOURCE" && main "$@"
-- 
cgit 1.4.1-21-gabe81