#!/bin/bash

#set -x
GMX_VERSION=2018.8

WORKDIR=$PWD
CMAKE_PARAMETERS="-DCMAKE_INSTALL_PREFIX=/usr/local/gromacs-${GMX_VERSION} -DGMX_HWLOC=off"

if [ -f /var/lib/install_gromacs-${GMX_VERSION} ]; then
	CMAKE_PARAMTERS_OLD=$(</var/lib/install_gromacs-${GMX_VERSION})
	if [ "$CMAKE_PARAMETERS" == "$CMAKE_PARAMTERS_OLD" ]; then
		NO_CHANGE=true
		echo "No change detected"
	else
		NO_CHANGE=false
		echo "Change detected"
	fi
else
	NO_CHANGE=false
	echo "Change detected, /var/lib/install_gromacs-${GMX_VERSION} not found"
fi


# if the former cmake parameters are the same
if [ -d /usr/local/gromacs-${GMX_VERSION} -a $NO_CHANGE = true ]; then
	echo "Assume $GMX_VERSION is installed"
	exit 0
else
	cd /tmp
	curl --fail https://ftp.gromacs.org/gromacs/gromacs-${GMX_VERSION}.tar.gz \
		--output gromacs-${GMX_VERSION}.tar.gz \
		--silent || echo "Version not found: gromacs-${GMX_VERSION}"
	tar xfz gromacs-${GMX_VERSION}.tar.gz
	rm gromacs-${GMX_VERSION}.tar.gz
	mkdir -p gromacs-${GMX_VERSION}/build
	# this patch is need because 2018.8 is *really* old by now
	if [ $GMX_VERSION==2018.8 ]; then
     	    pushd gromacs-${GMX_VERSION}
	    patch --verbose -p1 < $WORKDIR/compile_gromacs_2018.8_bookworm.patch
	fi
	popd
	pushd gromacs-${GMX_VERSION}/build
	cmake .. $CMAKE_PARAMETERS
	make -j $(nproc)
	make install -j $(nproc)
	popd
	rm -rf gromacs-${GMX_VERSION}
	# save parameters of installation
	echo $CMAKE_PARAMETERS > /var/lib/install_gromacs-${GMX_VERSION}
fi
echo "Run the following command to set the LD_LIBRARY_PATH in order to compile pygmx:"
echo "source /usr/local/gromacs-${GMX_VERSION}/bin/GMXRC"