#!/bin/csh -f
#+
# goi_wffcs_loop -- exposure loop with fcs tracking
#
# Purpose:
#       Wait for FCS to begin tracking, then acquire several exposures 
#	as specified by the default or the input parameter. For short 
#	exposures 30s or less, FCS will sometimes not have enough time 
#	between images to take data. So to ensure that FCS tracks consistently,
#	this script will loop over a specified number of exposures and then 
#	allow FCS to track before starting another exposure sequence. The 
#	script was developed for programs with long series (100 images) 
#	with relatively short exposures 30s. 
#
# Usage:
#       goi_wffcs_loop [interval [nexp]]
# 
# Arguments:
#       internval = number of exposures between wffcs [default=10]
#	nexp      = total number of science exposures to acquire [default=inf]
#
# Output:
#       None
# 
# Restrictions:
#	Note that this runs in an infinite loop. So to stop, you must
#	control C the script.
#
# Example:
#	1) Acquire exposures in infinite loop with a pause after every 10
#	exposures to allows FCS to track.
#		goi_wffcs_loop
#
#	2) Acquire 100 exposures with a pause after every 5
#	exposures to allows FCS to track.
#		goi_wffcs_loop 5 100
#
#-
# Modification history:
#	2013-Dec-13	MK/GDW	Original version
#-----------------------------------------------------------------------

set cmd = `basename $0`
set usage = "Usage: $cmd [interval [nexp]]\nDefault is to run 'wffcs; goi 10' with the current exposure parameters\n"
@ interval = 10
@ nexp = -1

# verify args...
if ( $#argv > 2 ) then
    printf "$usage\a"
    exit 1
endif

# parse args...
if ( $#argv >= 1 ) then 
    @ interval = $1 
    shift
endif

# parse args...
if ( $#argv >= 1 ) then 
    @ nexp = $1 
    shift
endif

# start loop...
@ count = 0
while ( 1 )
 
    # pause if image in progress...
    wfi -nowait

    # open the shutter to allow FCS to track...
    printf "Opening shutter..."
    modify -s deiccd cshutter=1 silent

    # wait for fcs exposure to complete...
    printf "wait for FCS readout..."
    wfifcs -silent

    # wait for tracking...
    printf "wait for FCS tracking..."
    wffcs
    printf "OK\n"

    # acquire science exposures...
    goi $interval

    # increment exposure count...
    @ count += $interval

    # check for quit...
    if ( $nexp > 0 ) then
	if ( $count < $nexp ) then
	    printf "Completed $count of $nexp exposure sequence.\n"
	else
	    printf "Completed $nexp exposure sequence.\n"
	    beep 3
	    break
	endif
    endif
end