#!/bin/sh

msg() {
	echo "==>" $@
}

die() {
	echo $@
	exit 1
}

APKS=tmp/apks

image=$PWD/image
dest=$PWD/test.gz
init=init


kernel=$1
# if no kernel specified, then guess...
if [ -z "$kernel" ]; then
	kernel=$(ls /lib/modules 2>/dev/null | tail -n 1)
fi

if [ ! -d /lib/modules/$kernel ]; then
	die "modules dir /lib/modules/$kernel was not found"
fi
msg "Using kernel $kernel"

# create empty image dir

rm -rf "$image"
mkdir -p "$image"

# unpack busybox and deps
tar -C $image -zxf $APKS/uclibc-[0-9]*.apk
tar -C $image -zxf $APKS/busybox-[0-9]*.apk
tar -C $image -zxf $APKS/alpine-baselayout-[0-9]*.apk
tar -C $image -zxf $APKS/apk-tools-[0-9]*.apk
rm -f $image/.PKGINFO
cp $init $image

# copy kernel modules
kmods=$image/lib/modules/$kernel
mkdir -p $kmods/kernel/drivers

for i in ata block ide ieee1394 scsi cdrom usb message; do
	cp -LpR /lib/modules/$kernel/kernel/drivers/$i $kmods/kernel/drivers/
done

for i in fs lib; do
	cp -LpR /lib/modules/$kernel/kernel/$i $kmods/kernel/
done

depmod $kernel -b $image
	

# generate the image
cd $image
find . | cpio -o -H newc | gzip -9 > $dest