#!/bin/sh

# Original by joshk@triplehelix.org, modifications by jilles@stack.nl

# Settings
# Don't customize here, create a dgl-create-chroot.conf file instead.
# The defaults should work fine for Debian.
# path for chroot
chroot_path="/var/lib/dgamelaunch"
# uid/gid (numeric), must agree with dgamelaunch.h
shed_uid=5
shed_gid=60
# extra libraries to copy (that ldd doesn't find, such as ld-elf.so.1 on
# FreeBSD)
libs=""
# compression binary to copy (found in $PATH if unqualified)
# (leave blank to skip)
compress_bin="gzip"
# nethack binary to copy (leave blank to skip)
nethack_bin="/usr/lib/games/nethack/nethack-console"
# fixed data to copy (leave blank to skip)
playground_fixed="/usr/lib/games/nethack"
# variable data to create (leave blank to skip) (may be equal to previous)
playground_var="/var/games/nethack"
# termcap/terminfo (copied recursively) (leave blank to skip)
termdata="/usr/share/terminfo"

[ -f dgl-create-chroot.conf ] && . ./dgl-create-chroot.conf

findlibs()
{
	for i in "$@"; do
		# () to ignore errors
		( ldd "$i" 2>/dev/null | awk '{ if ($2=="=>") print $3; }' )
	done
}
findinpath()
{
	local IFS
	IFS=:
	for dir in $PATH; do
		if [ -f "$dir/$1" ]; then
			echo "$dir/$1"
			return 0
		fi
	done
	return 1
}

set -e
umask 022

echo "Setting up the chroot in: $chroot_path"

mkdir -p $chroot_path/bin $chroot_path/etc $chroot_path/var/mail

# Passwd file
echo "games:*:$shed_uid:$shed_gid:games:/nonexistent:" >$chroot_path/etc/passwd
echo "games:*:$shed_gid:" >$chroot_path/etc/group

# Time zone information, NetHack uses this
[ -f /etc/localtime ] && cp /etc/localtime $chroot_path/etc

# Dungeon directory setup
mkdir -p $chroot_path/dgldir/inprogress
mkdir -p $chroot_path/dgldir/rcfiles
mkdir -p $chroot_path/dgldir/ttyrec
chown -R $shed_uid:$shed_gid $chroot_path/dgldir
chown -R $shed_uid:$shed_gid $chroot_path/var/mail
touch $chroot_path/dgl-login
touch $chroot_path/dgl-lock

# Might want to remove these two for packaging?
cp dgl-default-rcfile $chroot_path
cp dgl-banner $chroot_path

chown $shed_uid:$shed_gid $chroot_path/dgl-*

# Needs gzip to compress
if [ -n "$compress_bin" ]; then
	case "$compress_bin" in
	/*)	: ;;
	*)	compress_bin=`findinpath $compress_bin`	;;
	esac
	# NetHack wants the compression binary in the exact directory
	mkdir -p $chroot_path`dirname $compress_bin`
	cp $compress_bin $chroot_path$compress_bin
	libs="$libs `findlibs $compress_bin`"
fi

# Copy the nethack binary over
if [ -n "$nethack_bin" ]; then
	cp $nethack_bin $chroot_path/bin/nethack
	libs="$libs `findlibs $nethack_bin`"
fi

# ...and all the data it needs
if [ -n "$playground_var" ]; then
	mkdir -p $chroot_path$playground_var/save
	touch $chroot_path$playground_var/record
	touch $chroot_path$playground_var/perm
	touch $chroot_path$playground_var/logfile
	chown -R $shed_uid:$shed_gid $chroot_path$playground_var
fi

if [ -n "$playground_fixed" ]; then
	mkdir -p $chroot_path$playground_fixed
	cp $playground_fixed/license $chroot_path$playground_fixed
	if [ -e $playground_fixed/nhdat ]; then
		cp $playground_fixed/nhdat $chroot_path$playground_fixed
	else
		(
			cd $playground_fixed
			cp *.dat cmdhelp data dungeon help hh history \
				opthelp options perm recover rumors wizhelp \
				$chroot_path$playground_fixed
		)
	fi
fi

# Curses junk
if [ -n "$termdata" ]; then
	mkdir -p $chroot_path`dirname $termdata`
	if [ -d $termdata/. ]; then
		cp -R $termdata/. $chroot_path$termdata
	else
		cp $termdata $chroot_path`dirname $termdata`
	fi
fi

# Necessary libraries
# previously libs="/lib/libc.so.6 /lib/libncurses.so.5 /lib/ld-linux.so.2"
libs=`for lib in $libs; do echo $lib; done | sort | uniq`
echo "Copying libraries:" $libs
for lib in $libs; do
	mkdir -p $chroot_path`dirname $lib`
	cp $lib $chroot_path$lib
done

echo "Finished."