#!/bin/sh

echo
echo "OCaml and thus also MetaOCaml are not binary compatible from version to version."
echo "You (may) need to rebuild all installed packages with dependencies on dev-lang/ocaml."
echo

if [[ $1 == "-h" ]] || [[ $1 == "-help" ]] || [[ $1 == "--help" ]] 
then
    echo
    echo "Usage: ocaml-rebuild.sh [OPTIONS] [emerge_options]"
    echo
    echo "-h, --help       Display this help and exit."
    echo
    echo "-f, --force      Actually uninstall and reinstall all dependant packages."
    echo "                 If not given, just show the list."
    echo
    echo "    --byname     Run emerge based on package names, not exact versions."
    echo "                 This might upgrade (or downgrade) packages."
    echo "                 This won't fail, if the installed version's ebuild vanished from the tree."
    echo
    exit
fi

echo "Please wait..."
echo
 

if [ -x /usr/bin/equery ] 
then
    deps=$( (equery depends dev-lang/ocaml ; equery depends dev-ml/findlib) )
else
    echo "ATTENTION: You don't have gentoolkit installed on your system."
    echo "If you want me to build a propper list of all packages to be re-emerged," 
    echo "please emerge gentoolkit and re-run this script."
    echo
    for dep in `find /var/db/pkg -name DEPEND -exec grep -l 'dev-lang/ocaml\\|dev-ml/findlib' {} \;`
    do
        dir=`dirname $dep`
        pkg=`basename $dir`
        category=`cat $dir/CATEGORY`
        deps=$( echo -e "$deps\n$category/$pkg" )
    done
fi

if [[ $1 == "-byname" ]] || [[ $1 == "--byname" ]]
then
  deps=$( echo "$deps" | sed 's/-[1234567890][^\/]\+$//g' )
else
  echo "If emerge complains about some package being 'not a valid package atom'"
  echo "please consider using --byname as an option to this script (see --help)."
  echo
fi

if [[ $1 == "-f" ]] || [[ $1 == "-force" ]] || [[ $1 == "--force" ]] 
then
    echo "Please find the list of removed packages at /tmp/ocaml-rebuild.txt for later reference."
    echo "${deps}" > /tmp/ocaml-rebuild.txt
    echo
    echo "Removing packages..."
    echo
    emerge -C ${deps}
    echo
    echo "Rebuilding packages..."
    echo
    emerge ${deps}
    echo
    echo "done."
else
    echo "Here is a list of all packages to be rebuilt:"
    echo
    echo "${deps}" | while read next ; do echo "    $next" ; done
    echo

    echo "If you agree, just run the following command or use this script with '-f' option."
    echo
    echo "    $ emerge -C "${deps}
    echo
    echo "    $ emerge "${deps}
    echo
fi