/* DISCLAIMER 
 * ==========
 *
 * The University of Wisconsin-Madison Space Science and Engineering Center
 * (SSEC) makes no warranty of any kind with regard to the update_fy3_l1b_calb
 * software or any accompanying documentation, including but not limited to
 * the implied warranties of merchantability and fitness for a particular
 * purpose. SSEC does not indemnify any infringement of copyright, patent, or
 * trademark through the use or modification of this software.
 * 
 * There is no expressed or implied warranty made to anyone as to the
 * suitability of this software for any purpose. All risk of use is assumed by
 * the user.  Users agree not to hold SSEC, the University of
 * Wisconsin-Madison, or any of its employees or assigns liable for any
 * consequences resulting from the use of the update_fy3_l1b_calb software.
 */

#include <stdio.h>
#include <stdlib.h>
/* Use old version of HDF5: Version 1.6 */
#define H5_USE_16_API 1
#include <hdf5.h>

#define NR_QKM_DS 4 /* Number of QKM datasets */
#define NR_1KM_DS 15 /* Number of 1km datasets */

/* ======================= */
/* String global variables */
/* ======================= */
/* HDF5 data set names */
char qkm_refl_DS_name_str_pp [NR_QKM_DS][20] = {"EV_250_RefSB_b1",
                                                "EV_250_RefSB_b2",
                                                "EV_250_RefSB_b3",
                                                "EV_250_RefSB_b4"};
char km_refl_DS_name_str_pp [2][25] = {"EV_250_Aggr.1KM_RefSB", 
                                       "EV_1KM_RefSB"};
int  km_refl_DS_nr_attr_p [2] = {4, 15};
char cal_coeff_DS_name_str_p [20] = {"VIR_Cal_Coeff"};

/* New attribute names */
char ref_attr_str_p [3][3] = {"k0", "k1", "k2"};

/* Help message string */
char *help_str = "<FY L1B 250m file> <FY L1B 1000m file>";

/* ============= */
/* Main function */
/* ============= */
int main (int argc, char **argv) {
    int n_cal_coeff_int, n_km_attr_int, index, r_attr_index;
    double *attr_arr = NULL, *k0_attr_arr = NULL, *k1_attr_arr = NULL, *k2_attr_arr = NULL;
    /* These variables will be used accross multiple data sets */
    hid_t file_id, attr_type, lc_data_type;
    /* The following variables are only used when a dataset is opened */
    hid_t attr_id, attr_space, data_set;
    char *l1b_qkm_file_str_p, *l1b_1km_file_str_p;
    
    if (argc != 3) {
        fprintf (stderr, "[ERROR] Invalid number of input arguments.\n");
        fprintf (stderr, "\tUsage: %s %s\n", argv [0], help_str);

        return 1;
    }
    l1b_qkm_file_str_p = argv [1];
    l1b_1km_file_str_p = argv [2];

    /* ------------------------------------- */
    /* Update the data sets in the 250m file */
    /* ------------------------------------- */
    /* ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ */
    /* Load VIR_Cal_Coeff in a local array */
    /* ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ */
    file_id = H5Fopen (l1b_qkm_file_str_p, H5F_ACC_RDWR, H5P_DEFAULT);
    /* Get the calibration coefficients */
    attr_id = H5Aopen_name (file_id, cal_coeff_DS_name_str_p);
    /* Get data type of attribute */
    attr_type = H5Aget_type (attr_id);
    lc_data_type = H5Tcopy (H5T_NATIVE_DOUBLE);
    
    attr_space = H5Aget_space (attr_id);
    n_cal_coeff_int = (int) H5Sget_simple_extent_npoints (attr_space);
    attr_arr = (double *)malloc (sizeof (double) * n_cal_coeff_int);
    H5Aread (attr_id, lc_data_type, attr_arr);
    
    /* ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^*/
    /* Release attribute resources of 250m file */
    /* ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ */
    H5Sclose (attr_space);
    H5Aclose (attr_id);
    
    /* Scale the attribute values */
    for (index = 0; index < n_cal_coeff_int; ++index) {
        attr_arr [index] = attr_arr [index];
    }

    /* Create new attributes for each 250m reflectance dataset */
    for (index = 0; index < NR_QKM_DS; ++index) {
        /* Open the dataset */
        data_set = H5Dopen (file_id, qkm_refl_DS_name_str_pp [index]);
        /* Create data space for attribute */
        attr_space = H5Screate (H5S_SIMPLE);
        /* Set the charaterstics of the data space of the attribute */
        {
            hsize_t attr_space_size [1] = {1};
            H5Sset_extent_simple (attr_space, 1, attr_space_size, NULL);
        }

        /* Create the k0 attribute */
        /*attr_id = H5Acreate (data_set, ref_k0_attr_str_p, attr_type, attr_space, H5P_DEFAULT);*/
        /* Every third element in the VIR_Cal_Coeff array has the intercept value */
        /*H5Awrite (attr_id, lc_data_type, &(attr_arr [index * 3]));
        H5Aclose (attr_id);*/
        
        /* Create the k1 attribute */
        /*attr_id = H5Acreate (data_set, ref_k1_attr_str_p, attr_type, attr_space, H5P_DEFAULT);*/
        /* Every third element in the VIR_Cal_Coeff array has the slope value */
        /*H5Awrite (attr_id, lc_data_type, &(attr_arr [(index * 3) + 1]));
        H5Aclose (attr_id);*/

        for (r_attr_index = 0; r_attr_index < 3; ++r_attr_index) {
            attr_id = H5Acreate (data_set, ref_attr_str_p [r_attr_index], attr_type, attr_space, H5P_DEFAULT);
            H5Awrite (attr_id, lc_data_type, &(attr_arr [(index * 3) + r_attr_index]));
        }

        H5Sclose (attr_space);
        H5Dclose (data_set);
    }
    
    /* ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ */
    /* Release resources for 250m file */
    /* ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ */
    H5Tclose (attr_type);
    H5Tclose (lc_data_type);
    if (attr_arr != NULL) {
        free (attr_arr);
        attr_arr = NULL;
    }

    /* -------------------------------------- */
    /* Update the data sets in the 1000m file */
    /* -------------------------------------- */
    /* ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ */
    /* Load VIR_Cal_Coeff in a local array */
    /* ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ */
    file_id = H5Fopen (l1b_1km_file_str_p, H5F_ACC_RDWR, H5P_DEFAULT);
    /* Get the calibration coefficients */
    attr_id = H5Aopen_name (file_id, cal_coeff_DS_name_str_p);
    /* Get data type of attribute */
    attr_type = H5Aget_type (attr_id);
    lc_data_type = H5Tcopy (H5T_NATIVE_DOUBLE);
    
    attr_space = H5Aget_space (attr_id);
    n_cal_coeff_int = (int) H5Sget_simple_extent_npoints (attr_space);
    attr_arr = (double *)malloc (sizeof (double) * n_cal_coeff_int);
    H5Aread (attr_id, lc_data_type, attr_arr);
    
    n_km_attr_int = (n_cal_coeff_int / 3);
    /* Seperate the intercept and close values */
    k0_attr_arr = (double *)malloc (sizeof (double) * n_km_attr_int);
    k1_attr_arr = (double *)malloc (sizeof (double) * n_km_attr_int);
    k2_attr_arr = (double *)malloc (sizeof (double) * n_km_attr_int);
    for (index = 0; index < n_km_attr_int; ++index) {
        k0_attr_arr [index] = attr_arr [ index * 3];
        k1_attr_arr [index] = attr_arr [(index * 3) + 1];
        k2_attr_arr [index] = attr_arr [(index * 3) + 2];
    }
    
    for (index = 0; index < 2; ++index) {
        /* Open 1km data set */
        data_set = H5Dopen (file_id, km_refl_DS_name_str_pp [index]);
        /* Create data space for the attributes */
        attr_space = H5Screate (H5S_SIMPLE);
        /* Set charaterstics of the data space of the attribute */
        {
            hsize_t attr_space_size [1] = {km_refl_DS_nr_attr_p [index]};
            H5Sset_extent_simple (attr_space, 1, attr_space_size, NULL);
        }

        /* Create the k0 attribute */
        attr_id = H5Acreate (data_set, ref_attr_str_p [0], attr_type, attr_space, H5P_DEFAULT);
        H5Awrite (attr_id, lc_data_type, &(k0_attr_arr [index * 4]));
        H5Aclose (attr_id);

        /* Create the k1 attribute */
        attr_id = H5Acreate (data_set, ref_attr_str_p [1], attr_type, attr_space, H5P_DEFAULT);
        H5Awrite (attr_id, lc_data_type, &(k1_attr_arr [index * 4]));
        H5Aclose (attr_id);

        /* Create the k2 attribute */
        attr_id = H5Acreate (data_set, ref_attr_str_p [2], attr_type, attr_space, H5P_DEFAULT);
        H5Awrite (attr_id, lc_data_type, &(k2_attr_arr [index * 4]));
        H5Aclose (attr_id);
        
        H5Sclose (attr_space);
        H5Dclose (data_set);
    }

    /* ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ */
    /* Release resources for 1000m file */
    /* ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ */
    H5Tclose (attr_type);
    H5Tclose (lc_data_type);
    if (attr_arr != NULL) {
        free (attr_arr);
    }
    
    if (k0_attr_arr != NULL) {
        free (k0_attr_arr);
    }
    
    if (k1_attr_arr != NULL) {
        free (k1_attr_arr);
    }
    
    if (k2_attr_arr != NULL) {
        free (k2_attr_arr);
    }

    /* -------------------------- */
    /* Release resources for file */
    /* -------------------------- */
    H5Fclose (file_id);
        
    return 0;
}