#!/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"

    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'
                ;;
            *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'
                            ;;
                        *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*)
                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
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