Greatly improve UX when the list does not fit in the tmux pane (which

is almost always).  We scroll the list of folders with new mail slowly
up and down once before pausing, and we pause for much less time if we
have done that (because it takes a while).

The pauses are all hard-coded as are the tput sequences... but then
nobody but me even knows this exists, so meh.

foldercheck

@@ -4,12 +4,46 @@
 # sometimes so it must conform itself to its current size to look
 # respectable.
 
-alias my=typeset
-# pirate version:
-# alias me=typeset
+ORIG_CMD="$0 $*"
 
-sleep=$1
+MBLAZE=${MBLAZE-$HOME/.mblaze}
+profile="$MBLAZE/profile"
+
+date_fmt=$(mhdr -h FolderCheckDateFmt $profile)
+[ -z "$date_fmt" ] && date_fmt="%Y-%m-%d %H:%M"
+sleep=$(mhdr -h FolderCheckSleep $profile)
 [ -z "$sleep" ] && sleep=30
+default_sleep=$sleep
+
+TEMPFILES=""
+
+if [ $# -gt 0 ]; then
+	sleep=$1
+	shift
+fi
+
+################################################
+
+remember_tempfile () {
+	local fn=$1
+	case $TEMPFILES in
+		*${fn}*) ;;
+		*) TEMPFILES="${TEMPFILES} $fn" ;;
+	esac
+}
+
+forget_tempfile () {
+	local fn=$1
+	TEMPFILES=$(echo $TEMPFILES | perl -lpe "s,${fn},,gs; s,^\s+,,; s,\s+\$,,;")
+}
+
+ts () {
+	date +"$date_fmt"
+}
+
+debug () {
+	echo "$(ts) DEBUG: $*" 1>&2
+}
 
 stty_size_field () {
 	stty -a | perl -lne '/(\d+)\s+'$1'/ && print qq|$1\n|'
@@ -24,7 +58,7 @@ tty_cols () {
 }
 
 center_msg () {
-	my x y str mid_len
+	local x y str mid_len
 	str="$*"
 	mid_len=${#str}
 	mid_len=$(expr $mid_len / 2)
@@ -40,47 +74,152 @@ center_msg () {
 	tput sgr0 civis
 }
 
+count_file_lines () {
+	wc -l $1 | awk '{print $1}'
+}
+
+# ticker-tape-style file display in a potentially small window
+# if the output of rs doesn't fit nicely in the window, we
+# scroll it slowly down and then back up.
+# note: all this tput'ery works in a small tmux pane on OpenBSD, which
+# is where I run this... YMMV
+
+had=0
+display_file () {
+	local fn=$1 cols=$(tty_cols) rows=$(tty_rows) n=0 rs nlines thee_sleep=$sleep
+	[ -z "$cols" ] && cols=$COLUMNS
+	[ -z "$rows" ] && rows=$ROWS
+	tput clear
+	nlines=$(count_file_lines $fn)
+	if [ $nlines -eq 0 ]; then
+		center_msg '~no mail~'
+		had=0
+		return 0
+	fi
+	had=1
+	rs=${fn}.rs.txt
+	rs -e -w$cols <$fn >$rs
+	remember_tempfile $rs
+	n=$(count_file_lines $rs)
+	# suss out title
+	local title="~ $nlines w/new mail ~" mid_len x
+	mid_len=${#title}
+	mid_len=$(expr $mid_len / 2)
+	x=$(expr $cols / 2)
+	x=$(expr $x - $mid_len)
+	if [ $x -gt 0 ]; then
+		x=$(expr $x - 1)
+		title=$(printf %${x}s%s " " "$title")
+	fi
+	# looks purty
+	tput bold
+	echo "$title"
+	# sgr0=cancel effects(bold), sc=save position
+	tput sgr0 sc
+	if [ $n -lt $(expr $rows - 1) ]; then
+		cat $rs
+	else
+		local rm1=$(expr $rows - 2) r=0
+		local last=$(expr $n - $rm1)
+		# scroll the list forward slowly
+		while [ $r -le $last ]; do
+			# rc=return to saved position
+			# ed=clear to end of screen
+			tput rc ed
+			if [ $r -eq 0 ]; then
+				head -$rm1 $rs
+			else
+				sed -e "1,${r}d" <$rs | head -$rm1
+			fi
+			sleep 2
+			thee_sleep=$(expr $thee_sleep - 2)
+			r=$(expr $r + 1)
+		done
+		sleep 1 # pause between
+		thee_sleep=$(expr $thee_sleep - 1)
+		r=$(expr $r - 1)
+		while [ $r -ge 0 ]; do
+			tput rc ed
+			if [ $r -eq 0 ]; then
+				head -$rm1 $rs
+			else
+				sed -e "1,${r}d" <$rs | head -$rm1
+			fi
+			sleep 2
+			thee_sleep=$(expr $thee_sleep - 2)
+			r=$(expr $r - 1)
+		done
+		case $thee_sleep in
+			-*) thee_sleep="" ;;
+			*)
+				if [ $thee_sleep -gt 5 ]; then
+					thee_sleep=2
+				fi
+				;;
+		esac
+	fi
+	forget_tempfile $rs
+	rm -f $rs
+	sleep=$thee_sleep
+}
+
 check () {
-	my cols had=0 tmpf=$1
+	local cols tmpf=$1
 	cols=$(tty_cols)
 	[ -z "$cols" ] && cols=$COLUMNS
 	[ $had -eq 0 ] && center_msg '~looking...~'
 	mnewdirs > ${tmpf}
 	if [ ! -s "$tmpf" ]; then
+		tput clear
 		center_msg '~no unread mail~'
 		had=0
+		sleep=$default_sleep
 	else
-		[ $had -eq 0 ] && tput clear
-		cat ${tmpf} | rs -e -w$cols
-		had=1
+		display_file $tmpf
 	fi
 }
 
 sleeper_pid=0
 
 shleep () {
-	sleep $1 & sleeper_pid=$!
+	local secs=$1
+	sleep $secs & sleeper_pid=$!
 	wait $sleeper_pid 2>/dev/null
 	sleeper_pid=0
 }
 
 wakeup () {
-	[ $sleeper_pid -ne 0 ] && kill $sleeper_pid && wait $sleeper_pid
+	[ $sleeper_pid -ne 0 ] && \
+		kill $sleeper_pid >/dev/null 2>&1 && \
+		wait $sleeper_pid
+	sleep=0
 }
 
-tmpf=${TMPDIR-/tmp}/foldercheck.$$
+restart () {
+	tput clear sgr0 cvvis
+	exec $ORIG_CMD
+}
 
 interrupted () {
 	wakeup
+	if [ -n "$TEMPFILES" ]; then
+		echo "$(ts) cleaning up tempfiles: $TEMPFILES"
+		rm -rf $TEMPFILES
+	fi
 	rm -f ${tmpf}
-	reset
+	tput sgr0 cvvis
+	echo ''
+	echo "$(ts) exiting ..."
 	exit 1
 }
 
-trap 'interrupted' INT TERM QUIT
-trap 'wakeup' INFO WINCH
+trap 'interrupted' INT TERM
+trap 'wakeup; restart' INFO WINCH QUIT
+
+tmpf=${TMPDIR-/tmp}/foldercheck.$$
 
 while true; do
-	check ${tmpf}
-	shleep ${sleep}
+	check $tmpf
+	[[ -n "$sleep" ]] && shleep $sleep
+	sleep=$default_sleep
 done