#!/bin/sh
#
# Enable local models to link to GSL.
#
# Please run this script from BUILD_DIR, after ./configure,
# but before make.
#
# For linux.

echo "Enabling local models to link to GSL."
echo "Adding -lgsl -lgslcblas to HD_CXXLIBS"

file=../Xspec/src/main/Makefile
if [ -f $file ]; then
    echo " in file " $file

    # check if this script has been run already:
    if [ ! `grep -qs gsl $file` ]; then
	echo "Detected previously modified Makefile template:"
	echo $file
	echo "Refusing to modify again."
	exit 1
    fi
    
# This sed command finds the block beginning with HD_CXXFLAGS and 
# ending with a blank line. It then looks for lines in that block that
# do not contain a backslash (\) and that are not blank (blank lines are
# represented by ^$ ). There should be only one such line - the last. 
# The first command (s/$/ \\/) appends a space followed by a backslash 
# to the end of the line. The second command (// a\ etc.)
# appends the flag to include the header path on a new line.


    sed -e '/HD_CXXLIBS/,/^$/ {
    /\\/ !{
    /^$/ !{
    s/$/ \\/
    // a\
    \                      -lgsl -lgslcblas
    }
    }
    }
    ' $file > Makefile.temp

    echo "If this worked correctly, you should see it appended:" 

    sed -n -e '/HD_CXXLIBS/,/^$/ p' -e '/HD_SHLIB_LIBS/,/^$/ p' Makefile.temp
    mv Makefile.temp $file

fi
echo "Done!"