#!/bin/bash
set -e

mode_subst () {
    $fn >$bfn.new
}

mode_diff () {
    diff -u $dot $bfn.new || test $? = 1
}

mode_install () {
    mv -f $bfn.new $dot
}

mode=$1
case "$mode" in
subst|diff|install) ;;
*) echo >&2 'bad mode'; exit 1;
esac
shift

for fn in templates/*.in; do
    bfn=${fn%.in}
    dot=$HOME/.${bfn#*/}
    mode_$mode
done