#! /bin/bash
# configure script
# note: has nothing to do with GNU autoconf

exec 2> ${LOGFILE:-/dev/null} 3>&1
eval ${LOGFILE:+set -x}


shopt -s nullglob
export LC_ALL=C

CONF_DIR="${0%/*}"
CONF_OS="`uname -s`"
CONF_MACH="`uname -m`"
HAVE_GINAC=false
HAVE_MCC=false
CONF_BITS=

DEBUG=false
for arg in "$@" ; do
    case "$arg" in
        --debug)
            DEBUG=true ;;
        --prefix=*)
            CONF_PREFIX="${arg#--prefix=}" ;;
        --host=*)
            CONF_TARGET="${arg#--host=}" ;;
        --with-ginac)
            HAVE_GINAC=true ;;
        --with-mcc)
            HAVE_MCC=true ;;
        --32)
            CONF_BITS="-m32" ;;
        --64)
            CONF_BITS="-m64" ;;
        -*)
            echo "Warning: $arg is not a valid option." 1>&3 ;;
        *=*)
            eval "$arg" ;;
        *)
            echo "Warning: $arg is not a valid argument." 1>&3 ;;
    esac
done


test=test$$
trap "rm -fr $test* =." 0 1 2 3 15


## look for some programs

findprog() {
    echo -n "looking for $1... " 1>&3
    var="$2"
    set -- ${!var:+"${!var}"} "${@:3}"
    for prog in "$@" ; do
        full="`type -P "$prog"`" && {
            echo "$full" 1>&3
            printf -v "CONF_$var" "%q" "$full"
            return 0
        }
    done
    echo "no $@ in your path" 1>&3
    return 1
}
addflag() {
    eval "CONF_$1=\"\${CONF_$1} ${@:2}\""
}

gnuflags() {
    eval addflag FFLAGS -fdefault-real-8             # default double is 8 byte
    eval addflag FFLAGS -cpp                         # C pre-processor
    eval addflag FFLAGS -pedantic-errors -std=f2008  # folow f08 strictly
    eval addflag FFLAGS -J build                     # where to put mods
    eval addflag FFLAGS -Werror -Wall                # make every warning an error
    eval addflag FFLAGS -Wno-uninitialized 
}

findprog fortran FC  ifort gfortran  || exit 1



set -- `eval $CONF_FC --version -c | sed '/^$/d;s/([^)]*)//;q' 2>&1`
case "$1,$2,$3" in
    GNU,Fortran,[123].*)
        echo "Only version >= 4 are supported"
        exit
    ;;
    GNU,Fortran,4.*)
    echo "Code optimisation is *not* suported on gfortran 4"
        gnuflags
        eval addflag $CONF_BITS
        if $DEBUG ; then
            eval addflag FFLAGS -g -O0
            eval addflag FFLAGS -ffpe-trap=invalid,overflow 
            eval addflag FFLAGS -fdump-core -fbacktrace
            eval addflag FFLAGS -frange-check
            eval addflag FFLAGS -DDEBUG
        else
            eval addflag FFLAGS -DRELEASE
            eval addflag FFLAGS -march=native -mtune=native
        fi
    ;;
    GNU,Fortran,*)
        gnuflags
        eval addflag FFLAGS -Wno-maybe-uninitialized
        eval addflag $CONF_BITS
        if $DEBUG ; then
            eval addflag FFLAGS -g -O0
            eval addflag FFLAGS -ffpe-trap=invalid,overflow 
            eval addflag FFLAGS -fdump-core -fbacktrace
            eval addflag FFLAGS -fcheck=all -frange-check
            eval addflag FFLAGS -DDEBUG
        else
            eval addflag FFLAGS -DRELEASE -O3
            eval addflag FFLAGS -march=native -mtune=native
        fi
    ;;
    ifort*)
        eval addflag FFLAGS -autodouble
        eval addflag FFLAGS -module build
        eval addflag FFLAGS -fpp
        eval addflag FFLAGS -stand f03
        eval addflag $CONF_BITS
        if $DEBUG ; then
            eval addflag FFLAGS -g -O0
            eval addflag FFLAGS -DDEBUG
        else
            eval addflag FFLAGS -DRELEASE -O3
            eval addflag FFLAGS -xHost -fast
        fi
        if HAVE_GINAC ; then
            echo "Option --with-ginac is incompatible with ifort, disabling"
            HAVE_GINAC=false
        fi
        if HAVE_MCC ; then
            echo "Option --with-mcc is incompatible with ifort, disabling"
            HAVE_MCC=false
        fi
    ;;
    *)
        echo "Unknown compiler"
        exit
    ;;
esac

echo -n "extracting the Fortran libraries... " 1>&3

rm -fr $test*

tee $test.f90 << _EOF_ 1>&2
    program test
    integer i
    common /uscore/ i
    stop i
    end
_EOF_

while read line ; do
  set -- ${line//[:,()]/ }
  [[ "$1" =~ (/collect2|/ld|^ld)$ ]] && while test $# -gt 1 ; do
    shift
    case "$1" in
    *.o | -lc*)
      ;;
    -l* | -L* | *.a)
      FLDFLAGS+=" $1" ;;
    -Bstatic | -Bdynamic | *.ld)
      FLDFLAGS+=" -Wl,$1" ;;
    /*)
      FLDFLAGS+=" -L$1" ;;
    -rpath*)
      FLDFLAGS+=" -Wl,$1,$2"
      shift ;;
    -dynamic-linker)
      shift ;;
    esac
  done
done < <(eval $CONF_FC $CONF_FFLAGS -v -o $test $test.f90 2>&1)
echo "ok" 1>&3

eval addflag LFLAGS "$LDFLAGS $CONF_LDFLAGS $FLDFLAGS"



if ( $HAVE_GINAC || $HAVE_MCC ); then
    findprog gcc CC clang gcc || exit 1
    findprog g++ CXX clang++ g++ || exit 1
    eval addflag CFLAGS "-std=c99"

    ## does Fortran append underscores to symbols?

    echo -n "does $CONF_FC append underscores... " 1>&3

    tee $test-c.c << _EOF_ 1>&2
int uscore_ = 95;
int uscore = 59;
_EOF_

    for CONF_BITS in ${CONF_BITS:--m64 -m32} ; do
      eval $CONF_CC $CONF_CFLAGS $CONF_BITS -c $test-c.c 1>&2 || continue
      eval $CONF_FC $CONF_FFLAGS -o $test $test.f90 $test-c.o 1>&2 && break
    done

    ./$test
    case $? in
    95)
      echo "yes" 1>&3
      CONF_NOUNDERSCORE=0 ;;
    59)
      echo "no" 1>&3
      CONF_NOUNDERSCORE=1 ;;
    *)
      echo "error linking Fortran and C" 1>&3
      exit 1 ;;
    esac

else
    $CONF_CC=
    $CONF_CXX=
    $CONF_CFLAGS=
    $CONF_NOUNDERSCORE=
fi

#if ( $CONF_GINA || $CONF_MCC ); then
#
#fi