;$Author: nikos $
;$Date: 2021-02-21 18:49:50 -0800 (Sun, 21 Feb 2021) $
;$Header: /home/cdaweb/dev/control/RCS/hsave_struct.pro,v 1.3 2013/09/06 17:17:44 johnson Exp kovalick $
;$Locker: kovalick $
;$Revision: 29691 $
;
;Copyright 1996-2013 United States Government as represented by the 
;Administrator of the National Aeronautics and Space Administration. 
;All Rights Reserved.
;
;------------------------------------------------------------------
; Utilize IDL's SAVE procedure to save the structure a into the given filename.
;If data is stored in handles, make .dat structure tags and extract
;the data from the handles and put into the .dat tags, then wipe out
;the .handle tags.
FUNCTION hsave_struct,a,fname, debug=debug, nosave=nosave

if (tagindex('HANDLE',tag_names(a.(0))) eq -1) then begin
  if (not(keyword_set(nosave)))then begin ;save the buffer to the save file
    ; data is stored directly in the structure
    SAVE,a,FILENAME=fname
    endif else begin ;return the structure as is, since the data is already in the .dat tags
      return, a
    endelse

endif else begin
  ; data is stored in handles.  Retrieve the data from the handles,
  ; create .dat and re-create the structure, then SAVE to file.
  tn = tag_names(a) & nt = n_elements(tn) & cmd = 'SAVE,'

  for i=0,nt-1 do begin ; retrieve each handle value
    order = 'handle_value,a.(i).HANDLE,data'
     status = EXECUTE(order)
    ;delete each handle and also call handle_free otherwise
    ;memory wasn't being freed (added 5/7/2014)
;     a.(0).handle = 0
     HANDLE_FREE, a.(i).handle
     a.(i).handle = 0
     tmp = create_struct(a.(i),'dat',data)
     if (i eq 0) then data_buf = create_struct(a.(i).varname, tmp) else $
     data_buf = create_struct(data_buf, a.(i).varname, tmp)
   endfor

  if (not(keyword_set(nosave)))then begin ;save the buffer to the save file
    ; Add the filename keyword to save command
    cmd = cmd+"data_buf,FILENAME='"+fname+"'"
    if keyword_set(debug) then print, 'Saving data contents to ',fname
    status = execute(cmd) ; execute the save command
  endif else begin ;otherwise return the buffer to the calling program
    return, data_buf
  endelse

endelse
end