#!/bin/sh

## Note: The Makefile automatically invokes this script if necessary.

## This configure script does two things at the moment:
##
##   1. Checks that GHC is available (should also check for version >=5)
##
##   2. Picks a make tool. Humake is preferred if available
##      (except under Darwin), ghc --make is used otherwise.
##
## The result is recorded as links to scripts in the script/ subdirectory.
## Various Makefiles refer to these scripts.

### Auxiliary functions ########################################################
giveup() {
  echo "$@"
  echo "Giving up."
  exit 1
}

qwhich() {
  which "$@" 2>/dev/null
}

### Check that GHC is available ################################################
GHC=${GHC-ghc}
ghc=`${GHC} --numeric-version`

[ -n "$ghc" ] || giveup "${GHC} doesn't seem to work."
# Check that the version number is >=5...

echo "Using GHC version $ghc (the command is ${GHC})"

### Check which make tools are available #######################################

ghcxmake=`qwhich ghcxmake`

if [ "${USE_HUMAKE-yes}" != "yes" ] ; then
  echo "Not using Humake"
elif [ `uname` = Darwin ]; then
  echo "Humake is broken under Darwin (Mac OS X), skipping test."
else
  humake=`qwhich humake`
fi
[ -n "$humake" ] && ghumake=`qwhich ghumake`
[ -n "$ghumake" ] && ghuxmake=`qwhich ghuxmake`


### Pick make scripts ##########################################################

echo -n "Compiling plain Haskell programs with: "
if [ -n "$ghumake" ] ; then
  hsmake=myghumake
  echo "ghumake (Humake)"
else
  hsmake=myghc--make
  echo "ghc --make"
fi

echo -n "Compiling Haskell programs that use Fudgets with: "

if [ -n "$ghuxmake" ] ; then
  hsfudmake=myghuxmake
  echo "ghuxmake (Humake)"
elif [ -n "$ghcxmake" ] ; then
  hsfudmake=myghcxmake
  echo "ghcxmake (ghc --make)"
else
  echo "found no suitable tool!"
  #giveup ...
fi

### Checking for InternetLib ###################################################

I=InternetLib
B=pfe/Browser
L=/usr/local/lib
P=package.conf
[ -r "$B/$I/$P" ] || {
  if [ -r "$L/$I/$P" ] ; then
    echo "Using InternetLib found in $L"
    ln -s $L/$I $B/$I
  else
    echo "Didn't find InternetLib (in $L)."
    echo "Manually install it (in $L) or create a link to it in $B"
  fi
}

### Creating links to scripts ##################################################
cd scripts

rm -f hsmake.sh
ln -s "$hsmake" hsmake.sh

[ -n "$hsfudmake" ] && {
  rm -f hsfudmake.sh
  ln -s "$hsfudmake" hsfudmake.sh
}
### Done! ######################################################################