#!/bin/csh -f
#+
# fcsmov -- move a feature to a given position on the DEIMOS FCS image
#
# Purpose:
#	Given the starting pixel coordinates of an object on a
#	DEIMOS FCS image, and destination coordinates, 
#	compute and apply the required motor move to reposition
#	the object as desired.
#
# Usage:
#	fcsmov [-n] x1 y1 x2 y2
# 
# Arguments:
#	-n = no move, only print the required shift
#	x1 = starting column location of object [pixels]
#	y1 = starting row location of object [pixels]
#	x2 = ending column location of object [pixels]
#	y2 = ending row location of object [pixels]
# 
# Output:
# 
# Exit values:
#	0 = normal completion
#	1 = wrong number of arguments
#	2 = arguments not valid floating-point numbers
#
# Example:
#	1) Move a feature at guider pixel (100,200) to pixel (300,400):
#		fcsmov 100 200 300 400
#
#	2) Display the motor moves required to shift a target at
#	pixel (100,200) to the pixel (300,400) without moving the telecope:
#		fcsmov -n 100 200 300 400
#-
# Modification history:
#	2007-Jun-13	GDW	Original version
#       2007-Jun-15      MK     Added CCD switch to account for 
#                               different coordinate systems
#	2012-Jan-24	GDW	Added check for fcsmode
#-----------------------------------------------------------------------

set cmd = `basename $0`

#define constants
#midx defines the midpt between CCD1 and CCD2
set midx = 1200

# check for no-move flag...
if ( "$1" == "-n" ) then
  set string = "Required shift is"
  set move = 0
  shift
else
  set string = "Moving"
  set move = 1
endif

# check args...
if (${#argv} != 4) then  
  echo "Usage: fcsmov [-n] x1 y1 x2 y2"
  exit 1
endif

# verify floating-point values...
is_float $* > /dev/null
if ( $status ) then
  echo "ERROR: Arguments must be valid floating-point numbers"
  exit 2
endif

# verify FCS is Off...
set undesired = "Track"
set fcsmode = `show -s deifcs -terse fcsmode`
if ( $move && "$fcsmode" == "$undesired" ) then
    printf "[$cmd] ERROR: FCSMODE is currently set to '$fcsmode'.\n\tPlease stop FCS and try again.\n"
    exit 1
endif

#determine the appropirate offset for the Y direction (dy)
#If CCD1 is used (x1 <= midx) then the ydiff is a positive move
#If CCD2 is used (x1 > midx) then the ydiff is a negative move

if ($1 <= $midx) then
 set dy = `calc "$4 - $2"`
 set CCD = "CCD1"
else
 set dy = `calc "$2 - $4"`
 set CCD = "CCD2"
endif

# used as an explaination to observers
set dyout = `calc "$4 - $2"`


#determine the appropriate offset for the x direction (dx)
set dx = `calc "$3 - $1"`

echo "$string $dx $dyout"

if ( $move) then
  echo "Because x1 y1 are from $CCD"
  echo "Actual command issued is"
  echo "   fcsxy $dx $dy"
  fcsmove $dx $dy
endif