#!/bin/bash

# ==================================================================================================
# Purpose: This script is used to interpolate ms2gt row and column binary 
#     files which are produced by the ll2cr program. The interpolation is done 
#     by the IDL script ``interp_colrow.pro`` that was developed by 
#     Terry Haran - tharan@colorado.edu.
# 
# Input parameters:
#     1. The scale value with what the data should be interpolated with. This 
#        must be a natural number: 1, 2, 3, ...
#     2. The prefix string with what the output file names must start with. 
#     3. The ms2gt output column binary file, generated by the program ll2cr. 
#     4. The ms2gt output row binary file, generated by the program ll2cr.
# 
# Output: 
#     Two files are given to the script, and two output files will be 
#     generated. The output files with start with the prefix string given to the 
#     script.
#     The output file name convention will be as follows:
#     <prefix string>_<cols, rows>_<nr of rows>_<number of scans>_<always zero>_<number of rows per scan>.img
#     
#     Comments about the fields:
#     
#     Field 1. The prefix string could have a '_' character.
#     Field 2. This will be either equal to "rows" or "cols".
#     Field 3. Number of rows. This will always be a five digit number.
#     Field 4. The number of scans. This will always be a five digit number.
#     Field 5. The value of this field will always be zero. This will always be 
#              a five digit number.
#     Field 6. The number of rows per scan.
#
# Author: Willem.Marais@ssec.wisc.edu
# Date: 09/13/2012 
# ==================================================================================================

# Check if the IDL interpreter is available
if [ -z $IDL_CMD ]; then
    idl_path_str=$(which idl)
    if [ $? -ne 0 ]; then
        echo "(ERROR) Set the environmental variable IDL_CMD equal to the IDL interpreter path."
        exit 1
    fi
    
    IDL_CMD=$idl_path_str
fi

if [ $# -ne 4 ]; then
    echo "Usage: "
    echo "    "$(basename $0)" <scale factor> <tag> <ms2gt col file> <ms2gt row file>"
    
    exit 1
fi

interp_factor=$1
given_tag=$2
col_filein=$3
row_filein=$4

dir_col_filein=$(dirname $col_filein)
base_col_filein=$(basename $col_filein .img)
dir_row_filein=$(dirname $row_filein)
base_row_filein=$(basename $row_filein .img)

colsin=$(echo $base_col_filein | cut -d"_" -f 3 | bc)
scans=$(echo $base_col_filein | cut -d"_" -f 4 | bc)
rowsperscanin=$(echo $base_col_filein | cut -d"_" -f 6 | bc)
colsout=$(echo "$colsin * $interp_factor" | bc)

col_filein_parts=$(echo $base_col_filein | cut -d"_" -f 1)
row_filein_parts=$(echo $base_row_filein | cut -d"_" -f 1)
tag=$given_tag"-"$col_filein_parts

cat > runidl << EOF
interp_colrow, $interp_factor, $colsin, $scans, $rowsperscanin, '$col_filein', '$row_filein', $colsout, '$tag'
exit
EOF

if [ "$SCRIPT_DEBUG" == "YES" ]; then
    cat runidl
    $IDL_CMD runidl &> idl_output.txt
    idl_rtn=$?
    cat idl_output.txt
else
    $IDL_CMD runidl &> idl_output.txt
    idl_rtn=$?
fi

grep -i "Error" idl_output.txt &> /dev/null
if [ $? -eq 0 ] || [ $idl_rtn -ne 0 ]; then
    echo "(ERROR) The following IDL script failed."
    echo "========= IDL script ========="
    cat runidl
    echo "========= IDL output ========="
    cat idl_output.txt

    exit 1
fi

rm -f runidl idl_output.txt flsave.pro