;****************************************************************************
; Author  :  Josh Grant, COAPS
;
; Description : This program takes a divergence file which is in the format
;               previously specified for this project and grids each file. 
;
; **Warning** : Due to poor planning on my part and lack of time the bulk of
;               this program is not commented like it should be.
;****************************************************************************

PRO READFILE, filename, tempFile, data, times, ny, nx, err
command = "/usr/sbin/gunzip -c " + filename + " > " + tempFile
SPAWN, command, message

OPENR, input, filename, /GET_LUN, ERROR = err
IF ( err EQ 0 ) THEN BEGIN
    FREE_LUN, input
    OPENR, input, tempFile, /GET_LUN, ERROR = err
    print, "Reading " + filename
    line = FLTARR( 48 )
    newLine = ' '
    READF, input, ny, nx
    line = FLTARR( 48 )
    singletime = '9999999 '

    FOR pass = 0, 2 DO BEGIN
        FOR rows = 0, ny - 1 DO BEGIN
            READF, input, FORMAT = '(48F10.3)', line
            data( pass, *, rows ) = line
        ENDFOR
        READF, input, newLine
    ENDFOR
    FOR index = 0, ny - 1 DO BEGIN
        READU, input, singletime
        times( index ) = LONG(singletime)
    ENDFOR
    FREE_LUN, input

    print, "Done reading " + filename
    SPAWN, 'rm ' + tempFile
ENDIF
END

  dimensionsFile = "../others/dimensions.dat"
  base = "/Net/NSCAT/people/grant/diverg_proj/"
  swathsDirectory = base + "div2grid/data/daily_swath/"
  griddedDirectory = base + "div2grid/data/gridded/daily/"
  tempFile = "temp.div"

  miss = 99999.0
  time = LON64ARR( 18000 )
  data = FLTARR( 3, 48, 18000 )
  gridded = FLTARR( 360, 180 )
  totals = FLTARR( 360, 180 )
  ny = 0
  nx = 0

  start = 294
  endday = 366
  FOR year = 1997, 1997 DO BEGIN
    IF ( year EQ 1997 ) THEN BEGIN
      start = 139
      endday = 180
    ENDIF
    FOR number = start, endday DO BEGIN
      stringFormat = STRCOMPRESS( '(i' + STRING( 3 ) + '.' $
                    + STRING( 3 ) + ')', /REMOVE_ALL )

      file_name = swathsDirectory + STRTRIM( year, 1 ) + $
        STRING( number, format = stringFormat ) + '.div.gz'
      gridded_name = griddedDirectory + STRTRIM( year, 1 ) + $
        STRING( number, format = stringFormat ) + '.div.grid'
      READFILE, file_name, tempFile, data, time, ny, nx, error
      IF ( error EQ 0 ) THEN BEGIN

        gridded( *, * ) = miss
        totals( *, * ) = 0.0
        
        FOR col = 0, nx - 1 DO BEGIN
          FOR row = 0, ny - 1 DO BEGIN
            IF ( data( 2, col, row ) NE miss ) THEN BEGIN
              gridded_lat = FIX( data( 0, col, row ) + 90.5 )
              gridded_lon = FIX( data( 1, col, row ) + 0.5 )

              IF ( gridded_lon GT 359 ) THEN gridded_lon = 359
              IF ( gridded_lat GT 179 ) THEN gridded_lat = 179
              IF ( gridded( gridded_lon, gridded_lat ) EQ miss ) THEN BEGIN
                gridded( gridded_lon, gridded_lat ) = data( 2, col, row )
                totals( gridded_lon, gridded_lat ) = 1.0
              ENDIF ELSE BEGIN
                gridded( gridded_lon, gridded_lat ) = $
                  gridded( gridded_lon, gridded_lat ) + data( 2, col, row )
                totals( gridded_lon, gridded_lat ) = $
                  totals( gridded_lon, gridded_lat ) + 1.0
              ENDELSE
            ENDIF
          ENDFOR
        ENDFOR

        FOR lon = 0, 359 DO BEGIN
          FOR lat = 0, 179 DO BEGIN
            IF ( totals( lon, lat ) NE 0 ) THEN BEGIN
              gridded( lon, lat ) = gridded( lon, lat ) / totals( lon, lat )
            ENDIF
          ENDFOR
        ENDFOR

        OPENW, output, gridded_name, /GET_LUN
        printf, output, FORMAT = '(2I9)', time( 0 ), time( ny - 1 )
        FOR lat = 0, 179 DO BEGIN
          printf, output, FORMAT = '(360F10.3)', gridded( *, lat )
        ENDFOR
        FREE_LUN, output
      
        print, "Finished " + gridded_name
      ENDIF
    ENDFOR
  ENDFOR
END