#!/bin/sh

# install the gitolite software *system wide*.  Not too robust, fancy, etc.,
# but does have a usage message and catches simple problems.

usage() { echo "
    Usage:
        $0 [shared-bin-dir shared-conf-dir shared-hooks-dir]

    Installs the gitolite software (just the software, not keys or repos)
    within \$HOME when invoked by a user, or system-wide when invoked by root.

    Takes 0 or 3 absolute paths.  The first one must be part of \$PATH.

    Examples:
        # as root
        $0

        # this defaults to:
        $0 /usr/local/bin /var/gitolite/conf /var/gitolite/hooks

        # as a normal user
        $0

        # this defaults to:
        $0 \$HOME/bin \$HOME/share/gitolite/conf \$HOME/share/gitolite/hooks

    [RPM packagers: you can supply a 4th argument to specify a 'buildroot'
    directory.  DEB folks would call this a 'DESTDIR', I believe.  In this
    usage the first 3 arguments are NOT optional]
"
    exit 1;
}

die() { echo >&2; echo "$@" >&2; echo >&2; echo Run "$0 -h" for a detailed usage message. >&2; exit 1; }

[ "$1" = "-h" ] && usage

validate_dir() {
    echo $1 | grep '^/' >/dev/null || die "$1 should be an absolute path"
    [ -d $1 ] || mkdir -p $1 || die "$1 does not exist and could not be created"
}

# if we have a buildroot, set that up first
buildroot=$4;
[ -n "$buildroot" ] && validate_dir $buildroot
[ -n "$buildroot" ] && buildroot=$buildroot/

# either all 3 args must be supplied or none at all
[ -n "$1" ] && [ -z "$3" ] && die "I need all 3 directories or none at all"
# supply default values to args 1, 2, and 3 if not provided
[ -z "$1" ] && {
    euid=`perl -e 'print $>'`
    if [ "$euid" = "0" ]
    then
        set /usr/local/bin /var/gitolite/conf /var/gitolite/hooks
    else
        set $HOME/bin $HOME/share/gitolite/conf $HOME/share/gitolite/hooks
    fi
    echo "using default values for EUID=$euid:" >&2
    echo "$@" >&2
}

gl_bin_dir=$1; validate_dir $buildroot$gl_bin_dir
gl_conf_dir=$2; validate_dir $buildroot$gl_conf_dir
gl_hooks_dir=$3; validate_dir $buildroot$gl_hooks_dir

bindir=`echo $0 | perl -lpe 's/^/$ENV{PWD}\// unless /^\//; s/\/[^\/]+$//;'`
cd $bindir/..       # we assume the standard gitolite source tree is here!

cp src/* $buildroot$gl_bin_dir || die "cp src/* to $buildroot$gl_bin_dir failed"
perl -lpi -e "s(^GL_PACKAGE_CONF=.*)(GL_PACKAGE_CONF=$gl_conf_dir)" $buildroot$gl_bin_dir/gl-setup

# record which version is being sent across; we assume it's HEAD
if git rev-parse --is-inside-work-tree >/dev/null 2>&1
then
    git describe --tags --long --dirty=-dt 2>/dev/null > conf/VERSION || die "git describe failed -- your git is probably too old"
else
    [ -f conf/VERSION ] || echo '(unknown)' > conf/VERSION
fi

cp -R conf/* $buildroot$gl_conf_dir || die "cp conf/* to $buildroot$gl_conf_dir failed"
perl -lpi \
    -e "s(^#\s*\\\$GL_PACKAGE_CONF\s*=.*)(\\\$GL_PACKAGE_CONF = '$gl_conf_dir';)" \
        $buildroot$gl_conf_dir/example.gitolite.rc
perl -lpi \
    -e "s(^#\s*\\\$GL_PACKAGE_HOOKS\s*=.*)(\\\$GL_PACKAGE_HOOKS = '$gl_hooks_dir';)" \
        $buildroot$gl_conf_dir/example.gitolite.rc

cp -R hooks/* $buildroot$gl_hooks_dir || die "cp hooks/* to $buildroot$gl_hooks_dir failed"

# ----

# check if $gl_bin_dir is in $PATH and advise the user if needed
which=`which gl-setup 2>/dev/null`

path_advice="
Since gl-setup MUST be run from the PATH (and not as src/gl-setup or such),
you must fix this before running gl-setup.  The simplest way is to add

    PATH=$gl_bin_dir:\$PATH

to the end of your bashrc or similar file.  You can even simply run that
command manually each time you log in and want to run a gitolite command."

[ -z "$which" ] && die "                ***** WARNING *****
gl-setup is not in your \$PATH.
$path_advice"

which=`dirname $which`
[ "$which" != "$gl_bin_dir" ] && die "                ***** WARNING *****
$which precedes $gl_bin_dir in your \$PATH,
and it *also* contains gl-setup.  This is almost certainly going to confuse
you or me later.
$path_advice"