#!/usr/bin/env etsh
:
: etsh - " Force sh(1), csh(1), and other shells to exit w/ error! " <'' ;;;
:
: "  @(#)$Id: 2e0cf35531ac2f19d9222ba1ad54785135d5b8c7 $  "
:
: "  The author of this file, J.A. Neitzel <jan (at) etsh (dot) io>,  "
: "  hereby grants it to the public domain.                           "
:

:
: "  Cause the user's terminal to act as an alarm clock by repeatedly  "
: "  ringing the terminal bell at the specified time until the user    "
: "  snoozes it or turns it off.                                       "
:
: "  usage: ( alarm CCYYMMDDhhmm & )     "
: "     or:                              "
: "  usage: alarm CCYYMMDDhhmm &         "
: "     or:                              "
: "  usage: alarm [help | off | snooze]  "
:

umask	0077
setenv	TZ	EST5EDT ; : " Choose your time zone. "
if ! -e $h/.alarm -a ! -h $h/.alarm if ! { mkdir $h/.alarm } if { exit } false
if ! -d $h/.alarm -o   -h $h/.alarm if   { exit } perror $0 $h/.alarm'": Not a directory"'
chdir ; chdir .alarm

:
: " Check for correct usage. "
:
: >>$0'' <'' ; : >>$1'' <'' ; killer $0 alarm
if  $# = 0		goto Status
if X$1 = Xhelp		goto Usage
if X$1 = Xoff		goto Off
if X$1 = Xsnooze	goto Snooze
if ! { \
expr \
 //$1 : \
'//[0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9]*' = 14 \
     \& \
 //$1 : \
'//[0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9]*' = \
 //$1 : '//.*' \
} goto Usage >/dev/null
goto Continue

: Usage
fd2 -e -- head -5 ; false ; exit
usage: ( alarm CCYYMMDDhhmm & )
   or:
usage: alarm CCYYMMDDhhmm &
   or:
usage: alarm [help | off | snooze]

: Continue
if -e alarm if { exit } perror $0 '"Already running."'
if X$t != X goto Usage

:
: " Set everything up as needed... "
:
trap : 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22

( : " Fail if this process does not have a controlling terminal. " ) >/dev/tty

rm -f off snooze status timer alarm

if ! { touch -t $1 alarm } if { exit } false
date '+%Y%m%d%H%M%S' >timer

if timer -nt alarm rm -f alarm
if ! -e alarm if { exit } perror $0 '"Cannot ring alarm in the past."'

:
: " Create the status script for this alarm process. "
:
( \
  echo "echo "$$" | sed 's,^0*\(.*\),ps -p\1,' | etsh - | \
	sed 1d    | wc -c | tr -d ' \t' | grep '^0$' >/dev/null" ; \
  echo 'if $? = 0 if { exit } false' ; \
  echo "echo "$$" | sed 's,^0*\(.*\),ps -p\1,' | etsh - ; :" ; \
) >status

: Timer
	if ! \( -t 1 -a -t 2 \) goto Off
	sleep 60 ; date '+%Y%m%d%H%M%S' >timer
	if timer -ot alarm goto Timer
	if -e off goto Off
	rm -f snooze
	: fallthrough

: Alarm
	if ! \( -t 1 -a -t 2 \) goto Off
	bell 5 0.2 ; sleep 1
	if -e snooze if { sleep 600 } rm -f snooze
	if ! -e off goto Alarm
	: fallthrough

: Off
	rm -f snooze status timer alarm ; date '+%Y%m%d%H%M%S' >off ; exit

: Snooze
	if   -e snooze if { exit } perror $0 '"Already snoozing."'
	if ! -e status if { exit } perror $0 '"Not running."'
	if ! { etsh status >/dev/null } if { exit } perror $0 '"Not running."'
	if timer -ot alarm \
		if { exit } perror $0 '"Cannot snooze until alarm rings."'
	date '+%Y%m%d%H%M%S' >snooze
	exit

: Status
	if ! -e status if { exit } perror $0 '"Not running."'
	if ! { etsh status } if { exit } perror $0 '"Not running."'
	: zero status