configure

#!/bin/bash


############################## variables ##############################

description="Description: This script auto-generates a make.inc file for make compilation\n"
usage="Usage: ./configure [-h, --help] || [options]\n"
options="Options: \n\
    [-h, --help]            print help menu\n\
    [-m, --mpidir] mpidir   path to mpi (e.g. '~/.openmpi' or '/usr')\n\
    [-f, --fftdir] fftdir   path to fft (e.g. '/usr/local' or '~/.fftw-3.3.8')\n\
    [-c, --mpicom] mpicom   mpi executable used to compile code (e.g. 'mpifort')\n\
    [-e, --empty]           create empty 'make.inc' file for manual editing (overrides other options)\n"
mpicommands="mpifort mpiifort mpif90 mpif77"
lfftdir=false
indent="    "
fftwfile="fftw3.f03"
scriptdir=$(dirname $0)


############################## funcitons ##############################

function checkArguments(){
    # handles command line arguments
    lempty=false
    while [ ! -z "$1" ]; do
        if [ "$1" == "-h" ] || [ "$1" == "--help" ]; then
            printf "$description\n$usage\n$options"
            exit 0
        elif [ "$1" == "-e" ] || [ "$1" == "--empty" ]; then
            lempty=true
            break
        elif [ "$1" == "-m" ] || [ "$1" == "--mpidir" ]; then
            if [ -d "$2" ]; then
                mpidir=$(realpath $2)
                shift ; shift
            else
                echo "Error: Directory '$2' does not exist"
                exit 1
            fi
        elif [ "$1" == "-f" ] || [ "$1" == "--fftdir" ]; then
            if [ -d "$2" ]; then
                fftdir=$(realpath $2)
                shift ; shift
            else
                echo "Error: Directory '$2' does not exist"
                exit 1
            fi
        elif [ "$1" == "-c" ] || [ "$1" == "--mpicom" ]; then
            mpicom=$2
            shift ; shift
        else
            echo "Error: Command line option '$1' is not recognized"
            exit 1
        fi
    done
}


function findMPI_command(){
    # find mpi command
    if [ -z "$mpicom" ]; then
        lmpicom=false
        echo "${indent}Mpi compiler executable specified ... no"
        for mpicom in $mpicommands; do
            if type ${1}$mpicom > /dev/null 2>&1 ; then
                echo "${indent}Found mpi compiler ... $mpicom"
                lmpicom=true
                break
            fi
        done
        if ! $lmpicom ; then
            printf "Error: No fortran mpi compiler found. \n\
            Please use option [-c] to specify compiler name.\n"
            exit 1
        fi
    else
        lmpicom=true
        echo "${indent}Mpi compiler executable specified ... $mpicom"
    fi
}


function findMPI(){
    # find mpi directory and make call to findMPI_command
    if [ -z "$mpidir" ]; then
        echo "${indent}Mpi compiler path specified ... no"
        findMPI_command
        mpidir=$(dirname $(which $mpicom))
        fixMPIdir
        if [ ! -d "$mpidir" ]; then
            printf "Error: Could not resolve location of mpi compiler '$mpicom'. \n\
            Please use option [-m] to specify path to mpi compiler.\n"
            exit 1
        fi
        echo "${indent}Found mpi compiler path ... $mpidir"
    else
        echo "${indent}Mpi compiler path specified ... $mpidir"
        findMPI_command "$mpidir/bin/"
    fi
    if type $mpidir/bin/$mpicom > /dev/null 2>&1 ; then
        echo "${indent}Confirmed mpi command '$mpidir/bin/$mpicom' exists ... yes"
    else
        echo "Error: Command '$mpidir/bin/$mpicom' does not exist or is not executable."
        exit 1
    fi
}


function checkUserFFTW(){
    # check user provided fftw
    echo "${indent}Checking user pvodided FFTW ... $fftdir"
    if [ -d "$fftdir/include" ] && [ -f "$fftdir/include/$fftwfile" ] && [ -d "$fftdir/lib" ]; then
        lfftdir=true
    fi
    if $lfftdir; then
        echo "${indent}FFTW provided is valid ... yes"
    else
        echo "${indent}FFTW provided is valid ... no"
        echo "Error: Invalid fftw directory provided."
        exit 1
    fi
}


function fixMPIdir(){
    # remove '/bin' from path name 
    if [ $(echo $mpidir | rev | cut -d '/' -f1 | rev) == "bin" ]; then
        mpidir=$(echo $mpidir | rev | cut -d '/' -f2- | rev)
    fi
}


function locateFFTW(){
    # check user provided fftw
    for fftdir in $(for d in $(locate fftw | grep include | grep "$fftwfile"); do dirname $d; done); do 
        fftdir=$(realpath $fftdir | rev | sed -e 's/edulcni\///' | rev)
        if [ -d "$fftdir/lib" ]; then
            lfftdir=true
            break
        fi
    done
    if $lfftdir; then
        echo "${indent}FFTW found ... $fftdir"
    else
        echo "${indent}FFTW not found or version is not supported."
    fi
}


function createMakeInc(){
    # create make.inc
    make_inc="make.inc"
    cat > $make_inc << EOF
# Auto-generated make.inc file from configure

FC = ${mpidir}/bin/${mpicom}

flags = \\
    -ffree-line-length-none \\
    -pthread \\
    -fopenmp \\
    -lfftw3 \\
    -I${mpidir}/include \\
    -L${mpidir}/lib \\
EOF
    if [ "$fftdir" != "$mpidir" ]; then
        echo "${indent}-I${fftdir}/include \\" >> $make_inc
        echo "${indent}-L${fftdir}/lib \\" >> $make_inc
    fi
    echo >> $make_inc
}

############################### program ###############################

if [ "$PWD" != "$scriptdir" ]; then
    cd $scriptdir
fi

checkArguments $@
echo "Configuration to be written in 'make.inc'"
if $lempty ; then
    echo "${indent}Creating 'empty' make.inc for manual creation"
    mpidir=""
    mpicom=""
else
    echo "${indent}Collecting variables for creating make.inc"
    findMPI
    if [ ! -z $fftdir ]; then
        checkUserFFTW
    else
        locateFFTW
    fi
fi
createMakeInc
echo "Done! :)"