; docformat = 'rst'
;
; NAME:
;    getCameraExten
; PURPOSE:
;    Define the FITS extension to be read
;+
; :Description:
;    Define the FITS extension to be read
;
; :Categories:
;    FITS, Camera
;
; :Returns: An integer corresponding to the FITS extension
;
; :Params:
;    head: in, required, type=string
;        A FITS header from the telescope
;    cam: in, optional, type=string
;        The ID of the camera (from getCameraID)
;
; :Uses:
;    sxpar, getCameraID
;
; :Author:
;    B.Carry (OCA)
;
; :History:
;   Change History::
;      Written in December 2014, B. Carry (IMCCE)
;      2015-Jan. - B.Carry (IMCCE) - Added iKon@OHP-120, SPHERE@VLT
;      2015 Nov. - B.Carry (OCA) - Added compile option idl2
;      2016 Aug. - B.Carry (OCA) - Added EFOSC camera
;      2022 Nov. - B.Carry (OCA) - Added EFOSC camera
;      2023 Dec.: B.Carry (OCA) - Added LBTO
;      2024 Mar.: B.Carry (OCA) - Added VLT/ERIS/NIX
;-
function getCameraExten, head, cam
;-----------------------------------------------------------------------------------------------;
;-----------------------------------------------------------------------------------------------;
;---  TAG ---    I -- Initialization And Input Verification              -----------------------;
;-----------------------------------------------------------------------------------------------;
;-----------------------------------------------------------------------------------------------;
  COMPILE_OPT hidden, idl2

 ;--I.1-- Input Syntax Verification  ----------------------------------------------------
  if N_PARAMS() lt 1 then begin
    message, /IOERROR, 'Syntax : ID = getCameraExten(HEAD, [telID, camID])'
    return, -1
  endif

 ;--I.2-- Telescope and Camera ID  ------------------------------------------------------
  if not keyword_set(cam) then cam=getCameraID(head)


;-----------------------------------------------------------------------------------------------;
;-----------------------------------------------------------------------------------------------;
;---  TAG ---   II -- Header Parsing and Pole Angle Computation          -----------------------;
;-----------------------------------------------------------------------------------------------;
;-----------------------------------------------------------------------------------------------;

  case cam of

    ;--II.1-- ESO Telescopes  ---------------------------------------------------------------
    'NACO'        : exten=0
    'SPHERE/IRDIS': exten=0
    'ERIS/NIX'    : exten=0
    'ISAAC'       : exten=0
    'FORS2'       : exten=0
    'EFOSC'       : exten=0

    ;--II.2-- Keck Observatory  -------------------------------------------------------------
    'NIRC2'  : exten=0
    'NIRSPEC': exten=0

    ;--II.3-- Gemini Observatory  -----------------------------------------------------------
    'NIRI': exten=1

    ;--II.4-- Misc.  ------------------------------------------------------------------------
    'iKon-2k': exten=0
    'PUEO'   : exten=0
    'QHY600M': exten=0
    'Hokupaa': exten=0
    'PISCES': exten=0

    ;--II.x-- Unknown  ------------------------------------------------------------------------
     else: begin
       print, 'Camera '+cam+' not known!! Contact developers'
       stop
     end
  end


 ;----- Return FITS Extension  ----------------------------------------------------------
  return, exten
end