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/*
 *! (C) Copyright 2005-2015 ECMWF.
 *!
 *! This software is licensed under the terms of the Apache Licence Version 2.0
! * which can be obtained at http://www.apache.org/licenses/LICENSE-2.0.
 *!
! * In applying this licence, ECMWF does not waive the privileges and immunities granted to it by
! * virtue of its status as an intergovernmental organisation nor does it submit to any jurisdiction.
 */!
!
/*
! *FORTRAN C90 Implementation: bufr_read_temp
 *!
! * Description: how to read temperature significant levels from TEMP BUFR messages.
 *
 */

#include "eccodes.h"


int main(int argc,char* argv[])
{
  FILE* in = NULL;

  /* message handle. Required in all the eccodes calls acting on a message.*/
  codes_handle* h=NULL;

  char* units= NULL;
  char* unitsPercent= NULL;
  double *sigt_pres=NULL, *sigt_geo=NULL, *sigt_t=NULL;
  double *sigt_td=NULL;
  long longVal;
  double doubleVal;
  size_t sigt_len=0, desc_len=0, len=0;
  int i, err=0;
  int cnt=0;
  char* infile = "../../data/bufr/temp_101.bufr";
  char key_name[128];

  in=fopen(infile,"r");
  if (!in) {
    printf("ERROR: unable to open file %s\n", infile);
    return 1;
  }

  /* loop over the messages in the bufr file */
  while ((h = codes_handle_new_from_file(NULL,in,PRODUCT_BUFR,&err)) != NULL || err != CODES_SUCCESS)
  {
    if (h == NULL) {
      printf("Error: unable to create handle for message %d\n",cnt);
      cnt++;
      continue;
    }

    printf("message: %d\n",cnt);

    /* we need to instruct ecCodes to expand the descriptors 
     i.e. unpack the data values */
    CODES_CHECK(codes_set_long(h,"unpack",1),0);

    /* In what follows we rely on the fact that for 
     temperature significant levels the value of key 
     verticalSoundingSignificance is 4 (see flag table 8001 for details).
       
     We also make use of the fact that in our BUFR message
     verticalSoundingSignificance is always followed by geopotential, 
     airTemperature, dewpointTemperature,
     windDirection, windSpeed and pressure. */

    /* Get the number of the temperature significant levels.*/

    /* We find out the number of temperature significant levels by 
     counting how many pressure values we have on these levels. */
         
    sprintf(key_name,"/verticalSoundingSignificance=4/pressure");
    CODES_CHECK(codes_get_size(h,key_name,&sigt_len),0);

    printf("Number of T significant levels: %ld\n",sigt_len);

    /* Allocate memory for the values to be read. Each 
     parameter must have the same number of values. */
    sigt_pres = malloc(sigt_len*sizeof(double));
    sigt_geo = malloc(sigt_len*sizeof(double));
    sigt_t = malloc(sigt_len*sizeof(double));
    sigt_td = malloc(sigt_len*sizeof(double));
   
    /* Get pressure */
    
    sprintf(key_name,"/verticalSoundingSignificance=4/pressure");
   
    /* get the values */
    len=sigt_len;
    CODES_CHECK(codes_get_double_array(h,key_name,sigt_pres,&len),0);

    /* Get gepotential */

    sprintf(key_name,"/verticalSoundingSignificance=4/geopotential");

    /* check the size*/
    CODES_CHECK(codes_get_size(h,key_name,&len),0);
    if(len != sigt_len)
    {
      printf("inconsistent number of geopotential values found!\n");
      return 1;
    }    

    /* get the values */
    CODES_CHECK(codes_get_double_array(h,key_name,sigt_geo,&len),0);

    /* Get temperature */

    sprintf(key_name,"/verticalSoundingSignificance=4/airTemperature");

    /* check the size*/
    if(len != sigt_len)
    {
      printf("inconsistent number of temperature values found!\n");
      return 1;
    }    

    /* get the values */
    CODES_CHECK(codes_get_double_array(h,key_name,sigt_t,&len),0);

    /* Get dew point */

    sprintf(key_name,"/verticalSoundingSignificance=4/dewpointTemperature");

    /* check the size*/
    if(len != sigt_len)
    {
      printf("inconsistent number of dewpoint temperature values found!\n");
      return 1;
    }    

    /* get the values */
    CODES_CHECK(codes_get_double_array(h,key_name,sigt_td,&len),0);

    /* Print the values */
    
    printf("lev  pres    geo    t    td\n");
    printf("-------------------------------\n");
    
    for(i=0; i < sigt_len; i++)
    {
        printf("%3d %6.0f %6.0f %.1f %.1f\n",
           i+1,sigt_pres[i],sigt_geo[i],sigt_t[i],sigt_td[i]);
    }

    /* delete handle */
    codes_handle_delete(h);

    /*Release memory*/
    free(sigt_pres);
    free(sigt_geo);
    free(sigt_t);
    free(sigt_td);

    cnt++;
  }

  fclose(in);
  return 0;
}

!
! Please note that TEMP reports can be encoded in various ways in BUFR. Therefore the code
! below might not work directly for other types of TEMP messages than the one used in the
! example. It is advised to use bufr_dump first to understand the structure of these messages.
!
program bufr_read_temp
  use eccodes
  implicit none
  integer            :: ifile
  integer            :: iret
  integer            :: ibufr
  integer            :: i, count=0
  integer(kind=4),dimension(:), allocatable  :: timePeriod,extendedVerticalSoundingSignificance
  integer(kind=4)  :: blockNumber,stationNumber
  real(kind=8),dimension(:), allocatable :: pressure,airTemperature,dewpointTemperature
  real(kind=8),dimension(:), allocatable :: geopotentialHeight,latitudeDisplacement,longitudeDisplacement
  real(kind=8),dimension(:), allocatable :: windDirection,windSpeed

  call codes_open_file(ifile,'../../data/bufr/PraticaTemp.bufr','r')

  ! The first bufr message is loaded from file,
  ! ibufr is the bufr id to be used in subsequent calls
  call codes_bufr_new_from_file(ifile,ibufr,iret)
  do while (iret/=CODES_END_OF_FILE)
    write(*,*) 'message: ',count
    call codes_set(ibufr,'unpack',1)
    call codes_get(ibufr,'timePeriod',timePeriod)
    call codes_get(ibufr,'pressure',pressure)
    call codes_get(ibufr,'extendedVerticalSoundingSignificance',extendedVerticalSoundingSignificance)
    call codes_get(ibufr,'nonCoordinateGeopotentialHeight',geopotentialHeight)
    call codes_get(ibufr,'latitudeDisplacement',latitudeDisplacement)
    call codes_get(ibufr,'longitudeDisplacement',longitudeDisplacement)
    call codes_get(ibufr,'airTemperature',airTemperature)
    call codes_get(ibufr,'dewpointTemperature',dewpointTemperature)
    call codes_get(ibufr,'windDirection',windDirection)
    call codes_get(ibufr,'windSpeed',windSpeed)
    call codes_get(ibufr,'blockNumber',blockNumber)
    call codes_get(ibufr,'stationNumber',stationNumber)
    print *,'station',blockNumber,stationNumber
    print *,'timePeriod pressure geopotentialHeight latitudeDisplacement &
          &longitudeDisplacement airTemperature windDirection windSpeed significance'
    do i=1,size(windSpeed)
      write(*,'(I5,6X,F9.1,2X,F9.2,10X,F8.2,14X,F8.2,16X,F8.2,6X,F8.2,4X,F8.2,4X,I0)') timePeriod(i),pressure(i),&
          &geopotentialHeight(i),latitudeDisplacement(i),&
          &longitudeDisplacement(i),airTemperature(i),windDirection(i),windSpeed(i),extendedVerticalSoundingSignificance(i)
    enddo
    ! Free arrays
    deallocate(timePeriod)
    deallocate(pressure)
    deallocate(geopotentialHeight)
    deallocate(latitudeDisplacement)
    deallocate(longitudeDisplacement)
    deallocate(airTemperature)
    deallocate(dewpointTemperature)
    deallocate(windDirection)
    deallocate(windSpeed)
    deallocate(extendedVerticalSoundingSignificance)
    ! Release the bufr message
    call codes_release(ibufr)
    ! Load the next bufr message
    call codes_bufr_new_from_file(ifile,ibufr,iret)
    count=count+1
  end do
  ! Close file
  call codes_close_file(ifile)

end program bufr_read_temp