#!/bin/sh

split() {
    set -f
    old_ifs=$IFS
    IFS=$2
    set -- $1
    printf '%s ' "$@"
    IFS=$old_ifs
    set +f
}

hostos="$(uname -s | sed 's/\-.*//')"

#
# 1. Not specified
#   1.1 Automatically detect, then check compiler
#   1.2 If no fortran compiler is detected, gfortran is default with NOFORTRAN definition
# 2. Specified
#   2.1 If path is correct, check compiler
#   2.2 If path is not correct, but still valid compiler name, force setting
#     2.2.2 Path is not correct, invalid compiler name, then gfortran is default with NOFORTRAN definition
#

makefile="$1"
config="$2"

nofortran=0

shift 2
compiler="$*"
compiler_bin="$1"

# f77 is too ambiguous
[ "$compiler" = "f77" ] && compiler=''

path=`split "$PATH" ':'`

if [ -z "$compiler" ]; then

    lists="gfortran g95 frt fort openf90 openf95
	      sunf77 sunf90 sunf95
              xlf95 xlf90 xlf
              ppuf77 ppuf95 ppuf90 ppuxlf
	      pathf90 pathf95
	      pgf95 pgf90 pgf77 pgfortran nvfortran
	      flang egfortran
              ifort nagfor ifx ftn crayftn"

    for list in $lists; do
        for p in $path; do
            if [ -x "$p/$list" ]; then
                compiler=$list
                compiler_bin=$list
                break 2
            fi
        done
    done
fi

if [ -z "$compiler" ]; then

    nofortran=1
    compiler=gfortran
    vendor=GFORTRAN
    bu="_"

else
    {
        data="$(command -v "$compiler_bin" >/dev/null 2>&1)"
        vendor=""
    } && {
    	data=`$compiler -O2 -S ftest.f > /dev/null 2>&1 && cat ftest.s && rm -f ftest.s`
    	if [ -z "$data" ]; then
    		data=`$compiler -O2 -S ftest.f > /dev/null 2>&1 && cat ftest.c && rm -f ftest.c`
    	fi

        case "$data" in *zhoge_*) bu=_ ;; esac

        case "$data" in
            *Fujitsu*)
                vendor=FUJITSU
                openmp='-Kopenmp'
                ;;
	    *Cray*)
		vendor=CRAY
		openmp='-fopenmp'
		;;
            *GNU*|*GCC*)

                v="${data#*GCC: *\) }"
                v="${v%%\"*}"

                major="${v%%.*}"

                if [ "$major" -ge 4 ]; then
                    vendor=GFORTRAN
                    openmp='-fopenmp'
                else
                    case "$compiler" in
                        *flang*)
                            vendor=FLANG
                            openmp='-fopenmp'
                            ;;
                        *ifx*)
                            vendor=INTEL
                            openmp='-fopenmp'
                            ;;
                        *pgf*|*nvf*)
                            vendor=PGI
                            openmp='-mp'
                            ;;
                        *)
                            vendor=G77
                            openmp=''
                            ;;
                    esac
                fi
                ;;
            *g95*)
                vendor=G95
                openmp=''
                ;;
            *Intel*)
                vendor=INTEL
                openmp='-fopenmp'
                ;;
            *'Sun Fortran'*)
                vendor=SUN
                openmp='-xopenmp=parallel'
                ;;
            *PathScale*)
                vendor=PATHSCALE
                openmp='-openmp'
                ;;
            *Open64*)
                vendor=OPEN64
                openmp='-mp'
                ;;
            *PGF*|*NVF*)
                vendor=PGI
                openmp='-mp'
                ;;
            *'IBM XL'*)
                vendor=IBM
                openmp='-openmp'
                ;;
            *NAG*)
                vendor=NAG
                openmp='-openmp'
                ;;
        esac

    	# for embedded underscore name, e.g. zho_ge, it may append 2 underscores.
    	data=`$compiler -O2 -S ftest3.f >/dev/null 2>&1 && cat ftest3.s && rm -f ftest3.s`

    	[ -z "$data" ] && {
    		data=`$compiler -O2 -S ftest3.f >/dev/null 2>&1 && cat ftest3.c && rm -f ftest3.c`
    	}

    	case "$data" in *' zho_ge__'*) need2bu=1 ;; esac
    	case "$vendor" in *G95*) [ "$NO_LAPACKE" != 1 ] && need2bu='' ;; esac
	}

    if [ -z "$vendor" ]; then
        case "$compiler" in
            *g77*)
                vendor=G77
                bu=_
                openmp=''
                ;;
            *g95*)
                vendor=G95
                bu=_
                openmp=''
                ;;
            *gfortran*)
                vendor=GFORTRAN
                bu=_
                openmp='-fopenmp'
                ;;
            *ifort*|*ifx*)
                vendor=INTEL
                bu=_
                openmp='-fopenmp'
                ;;
            *pathf*)
            	vendor=PATHSCALE
            	bu=_
            	openmp='-mp'
            	;;
            *pgf*|*nvf*)
                vendor=PGI
                bu=_
                openmp='-mp'
                ;;
            *ftn*)
            	vendor=PGI
            	bu=_
            	openmp=-openmp
            	;;
            *frt*)
                vendor=FUJITSU
                bu=_
                openmp='-openmp'
                ;;
            *sunf77*|*sunf90*|*sunf95*)
                vendor=SUN
                bu=_
                openmp='-xopenmp=parallel'
                ;;
            *ppuf*|*xlf*)
                vendor=IBM
                openmp='-openmp'
                ;;
            *open64*)
                vendor=OPEN64
                openmp='-mp'
                ;;
            *flang*)
                vendor=FLANG
                bu=_
                openmp='-fopenmp'
                ;;
            *nagfor*)
                vendor=NAG
                bu=_
                openmp='-openmp'
                ;;
        esac

    	if [ -z "$vendor" ]; then
    	    nofortran=1
    	    compiler="gfortran"
    	    vendor=GFORTRAN
    	    bu=_
    	    openmp=''
    	fi
    fi
fi

{
    data=`command -v $compiler_bin >/dev/null 2>&1`
} && {

    binary=$BINARY

    [ "$USE_OPENMP" != 1 ] && openmp=''

    case "$binary" in
        32)
            {
                link=`$compiler $openmp -m32 -v ftest2.f 2>&1 && rm -f a.out a.exe`
            } || {
                link=`$compiler $openmp -q32 -v ftest2.f 2>&1 && rm -f a.out a.exe`
            } || {
                # for AIX
                link=`$compiler $openmp -maix32 -v ftest2.f 2>&1 && rm -f a.out a.exe`
            } || {
                # for gfortran MIPS
                mips_data=`$compiler_bin -E -dM - < /dev/null`
                case "$mips_data" in
                    *_MIPS_ISA_MIPS64*)
                        link=`$compiler $openmp -mabi=n32 -v ftest2.f 2>&1 && rm -f a.out a.exe`
                        ;;
                    *)
                        link=`$compiler $openmp -mabi=32 -v ftest2.f 2>&1 && rm -f a.out a.exe`
                        ;;
                esac
            } || {
                binary=''
            }
            ;;
        64)
            {
                link=`$compiler $openmp -m64 -v ftest2.f 2>&1 && rm -f a.out a.exe`
            } || {
                link=`$compiler $openmp -q64 -v ftest2.f 2>&1 && rm -f a.out a.exe`
            } || {
                # for AIX
                link=`$compiler $openmp -maix64 -v ftest2.f 2>&1 && rm -f a.out a.exe`
            } || {
                # for gfortran MIPS
                link=`$compiler $openmp -mabi=64 -v ftest2.f 2>&1 && rm -f a.out a.exe`
            } || {
                # for nagfor
                link=`$compiler $openmp -dryrun ftest2.f 2>&1 && rm -f a.out a.exe`
            } || {
                binary=''
            }
            ;;
    esac

    if [ -z "$binary" ]; then
        link=`$compiler $openmp -v ftest2.f 2>&1 && rm -f a.out a.exe`
    fi
}

if [ "$vendor" = "NAG" ]; then
    link=`$compiler $openmp -dryrun ftest2.f 2>&1 && rm -f a.out a.exe`
fi
if [ "$vendor" = "CRAY" ]; then
    link=`$compiler $openmp -hnopattern ftest2.f 2>&1 && rm -f a.out a.exe`
fi
linker_L=""
linker_l=""
linker_a=""

if [ -n "$link" ]; then

    link=`echo "$link" | sed 's/\-Y[[:space:]]P\,/\-Y/g'`

    link=`echo "$link" | sed 's/\-R[[:space:]]*/\-rpath\%/g'`

    link=`echo "$link" | sed 's/\-rpath[[:space:]]+/\-rpath\%/g'`

    link=`echo "$link" | sed 's/\-rpath-link[[:space:]]+/\-rpath-link\%/g'`

    flags=`echo "$link" | tr "',\n" " "`
    # remove leading and trailing quotes from each flag.
    #@flags = map {s/^['"]|['"]$//g; $_} @flags;

    for flag in $flags; do
        case "$flag" in -L*)
            case "$flag" in
                -LIST:*|-LANG:*) ;;
                *) linker_L="$linker_L $flag" ;;
            esac
        esac

    	case "$flag" in -Y*)
    	    [ "$hostos" = "SunOS" ] && continue
    	    linker_L="$linker_L -Wl,$flag"
    	    ;;
        esac

    	case "$flag" in --exclude-libs*)
            linker_L="$linker_L -Wl,$flag"
            flag=""
            ;;
        esac

    	case "$flag" in -rpath%*)
    	    flag=`echo "$flag" | sed 's/\%/\,/g'`
    	    linker_L="$linker_L -Wl,$flag"
        esac

    	case "$flag" in -rpath-link%*)
    	    flag=`echo "$flag" | sed 's/\%/\,/g'`
    	    linker_L="$linker_L -Wl,$flag"
    	    ;;
    	esac

    	case "$flag" in *-lgomp*)
    	    case "$CC" in *clang*)
    	        flag="-lomp"
    	        ;;
    	    esac
    	esac

        case "$flag" in -l*)
            case "$flag" in
                *ibrary*|*gfortranbegin*|*flangmain*|*frtbegin*|*pathfstart*|\
                    *crt[0-9]*|*gcc*|*user32*|*kernel32*|*advapi32*|*shell32*|\
                    -l) ;;
                *omp*)
                    case "$vendor" in
                        *PGI*|*FUJITSU*) ;;
                        *) linker_l="$linker_l $flag" ;;
                    esac
                    ;;
                *[0-9]*)
                    if [ "$vendor" = "FUJITSU" ]; then
                        case "$flag" in
                            -lfj90*) linker_l="$linker_l $flag" ;;
                            *) ;;
                        esac
                    fi
                    ;;
                *) linker_l="$linker_l $flag" ;;
            esac
    	esac

        case "$flag" in *quickfit.o*)
            [ "$vendor" = "NAG" ] && linker_l="$linker_l $flag" ;;
        esac

        case "$flag" in *safefit.o*)
            [ "$vendor" = "NAG" ] && linker_l="$linker_l $flag" ;;
        esac

        case "$flag" in *thsafe.o*)
            [ "$vendor" = "NAG" ] && linker_l="$linker_l $flag" ;;
        esac

    	case "$flag" in *.a) linker_a="$linker_a $flag" ;; esac
    done
fi

if [ "$vendor" = "FLANG" ]; then
    linker_a="$linker_a -lflang"
fi

printf "F_COMPILER=%s\n" "$vendor"               >> "$makefile"
printf "FC=%s\n" "$compiler"                     >> "$makefile"
[ -n "$bu" ] && printf 'BU=%s\n' "$bu"           >> "$makefile"
[ "$nofortran" -eq 1 ] && printf 'NOFORTRAN=1\n' >> "$makefile"

[ -n "$bu" ] && printf '#define BUNDERSCORE\t%s\n' "$bu"    >> "$config"
[ -n "$bu" ] && printf '#define NEEDBUNDERSCORE\t1\n'       >> "$config"
[ -n "$need2bu" ] && printf "#define NEED2UNDERSCORES\t1\n" >> "$config"

[ -n "$need2bu" ] && printf "#define NEED2UNDERSCORES=1\n"  >> "$config"

if [ -n "$linker_l" ] || [ -n "$linker_a" ]; then
    printf "FEXTRALIB=%s %s %s\n" "$linker_L" "$linker_l" "$linker_a" >> "$makefile"
fi