; 
; PURPOSE:  Calculate date and time that correspond to a fractional crn:Cl0
; CALLING SEQUENCE :
;  datetime_scrncl0_200905,crn,cl0,reso,year,month,day,hh,mm,ss,/plt
; IUPUT:   crn,cl0,reso
; OUTPUT:  year,month,day,hh,mm,ss,/plt
; MODIFICATION HISTORY :
;    First version: 20090531 by X. Zhao based on datetime_scrncl0.pro
;                   20060327 by X. Zhao
;
;pro date_crncrlz3,crn,crl,reso,date,crli,date0,PLT=plt
pro date_crncrlz3,crn,crl,date,crli,date0,PLT=plt

    if N_params() LT 1 then begin
       print,'date_crncrlz3,crn,crl,date,crli,date0,/plt'
       print,"crn=2081 & crl=180.50, crn=2079 & crl=150.00, 360.00"
       print,'reso=1,10,60,300,600 sec'
       return
    endif
    lim=0.0166667
  ; CASE 1 OF
  ;  reso eq 600: lim=0.166667            ; 600 sec = 10 min. = 0.166667 hr
  ;  reso eq 300: lim=0.0833333
  ;  reso eq 60:  lim=0.0166667
  ;  reso eq 50:  lim=0.0138889
  ;  reso eq 30:  lim=0.00833333
  ;  reso eq 10:  lim=0.00277778
  ;  reso eq 1:   lim=0.000277778
  ; ENDCASE
    scrncrl=STRTRIM(crn,2)+':'+STRTRIM(crl,2)
    spawn,'suninfo ct'+scrncrl+' > outd.d'
    str0=' ' 
    get_lun,unit
    openr,unit,'outd.d'
    for ii=0,6 do readf,unit,str0
    free_lun,unit
    spawn,'rm outd.d'
    ln=STRLEN(str0)
    date0=STRMID(str0,ln-26,22)
    year_sec_date,date0,year,month,day,hh,mm,ss          ; NEW
    fhr01=mm/60.+ss/3600.
    fhr0=hh+fhr01
; print,'str0,fhr0,crl:',str0,fhr0,crl
    crli_date_suninfo,date0,crn,crli                     ; NEW
    dcl=crli-crl
    if ABS(dcl) gt 100 then crli=crli+360
    dcl=crli-crl
if keyword_set(plt) then print,'date0,crli,dcl:',date0,crli,dcl
    CASE 1 OF
; Case 1
       dcl gt 0.005: begin
        lbl1:      if hh eq 23 then begin
                      day=day+1
                      fhr=fhr01
                   endif else fhr=fhr0
                   fhr=fhr+lim              ;fhr=fhr+1.
                   hh=FIX(fhr) & mm=FIX((fhr-hh)*60) & ss=FIX(((fhr-hh)*60-mm)*60)
                   date_year_sec,year,month,day,hh,mm,ss,date
                   crli_date_suninfo,date,crn,crli
                   dcl=crli-crl
                   if ABS(dcl) gt 100 then crli=crli+360
                   dcl=crli-crl
         if keyword_set(plt) then print,'C1-crli,dcl:',crli,dcl
                   if dcl gt 0.005 then goto, lbl1 else day1=day+fhr/24.
                   end
; Case 2
       dcl lt -0.005: begin
                    if hh eq 0 then begin
                       day=day-1
                       fhr0=23+fhr01
                       fhr=fhr0
                    endif else fhr=fhr0
        lbl3:       if mm eq 0 then begin
                       mm=60
                       if (hh eq 0) then begin
                          day=day-1
                          hh=24
                       endif
                       hh=hh-1
                       fhr1=mm/60.+ss/3600.
                       fhr=hh+fhr1
                    endif 
                   fhr=fhr-lim
                   hh=FIX(fhr) & mm=FIX((fhr-hh)*60) & ss=FIX(((fhr-hh)*60-mm)*60)
                   date_year_sec,year,month,day,hh,mm,ss,date
                   crli_date_suninfo,date,crn,crli
                   dcl=crli-crl
        if keyword_set(plt) then  print,'C2-date,crli,dcl:',date,crli,dcl
                   if dcl lt -0.005 then goto, lbl3 else day1=day+fhr/24.
                    end
       else: day1=day+fhr0/24.
     ENDCASE
     fhr1=(day1-day)*24.
     if hh eq 24 then begin
        day=day+1
        hh=0
     endif
     date_year_sec,year,month,day,hh,mm,ss,date1
;    if keyword_set(plt) then begin
        print,'Orig. crl and initial date:',crl,' ',date0
        print,'Last crli and date        :',crli,' ',date
;    endif

end