#!/bin/sh

# apk add blkid parted dosfstools e2fsprogs wget tar
set -eu

: "${DISK:=m1-install.img}"
: "${DISKSIZE:=528M}"

readonly SCRIPT="${0##*/}"
readonly TMPDIR="$(mktemp -dt "${SCRIPT%.*}".XXXXXX)"
readonly APK_KEY="alpine-devel@lists.alpinelinux.org-60ac2099.rsa.pub"
readonly MIRROR="http://dl-cdn.alpinelinux.org/alpine"
readonly LOOPDEV="$(losetup --find)"
readonly BOOTDEV="$LOOPDEV"p4
readonly ROOTDEV="$LOOPDEV"p5

cleanup() {
	set +e
	mountpoint -q "$TMPDIR"/boot/efi && umount "$TMPDIR"/boot/efi
	mountpoint -q "$TMPDIR" && umount "$TMPDIR"
	losetup --detach-all
	rm -rf "$TMPDIR"
}

trap cleanup EXIT INT

rm -f $DISK
truncate -s $DISKSIZE $DISK

echo "Paritioning disk"
sgdisk --clear \
  --set-alignment=2 \
  --new=4::+128MiB: --change-name=4:ESP --typecode=4:EF00 \
  --new 5::+300MiB: -c 5:root \
"${DISK}"

echo "Creating dirs and mounting"
losetup -P "$LOOPDEV" "$DISK"
mkfs.fat -F 32 -n ESP "$BOOTDEV"
mkfs.ext4 -b 4096 -qL root "$ROOTDEV"
mount -t ext4 "$ROOTDEV" "$TMPDIR"
mkdir -p "$TMPDIR"/boot
mkdir -p "$TMPDIR"/boot/efi "$TMPDIR"/etc/apk/keys
mount -t vfat "$BOOTDEV" "$TMPDIR"/boot/efi
mkdir -p "$TMPDIR"/boot/efi/m1n1

echo "Setup apk keys and repositories"
wget -qP "$TMPDIR"/etc/apk/keys https://alpinelinux.org/keys/"$APK_KEY"
printf "$MIRROR/edge/%s\n" main community testing > "$TMPDIR"/etc/apk/repositories

echo "installing base packages"
apk --allow-untrusted --root "$TMPDIR" --arch aarch64 --initdb add \
	alpine-base alpine-baselayout alpine-conf kmod openrc \
  dbus util-linux blkid chrony \
	sysfsutils ssl_client ca-certificates-bundle alpine-keys \
	ethtool e2fsprogs e2fsprogs-extra eudev sgdisk \
	iwd linux-firmware-none \
	nvme-cli agetty terminus-font openresolv tar wget btrfs-progs f2fs-tools \
	m1n1 u-boot-asahi mkinitfs \
	efibootmgr font-dejavu \
	speakersafetyd asahi-fwextract

apk --allow-untrusted --root "$TMPDIR" --arch aarch64 --no-script add grub-efi grub-mkfont
apk --allow-untrusted --root "$TMPDIR" --arch aarch64 --no-script add linux-asahi

echo "Setting up services and inittab"
for rc in boot/bootmisc boot/hostname boot/modules boot/sysctl boot/urandom boot/networking \
	sysinit/devfs sysinit/hwdrivers	sysinit/modules \
	sysinit/udev sysinit/udev-settle sysinit/udev-trigger \
	shutdown/mount-ro shutdown/killprocs \
	default/dbus default/udev-postmount default/chronyd default/local default/speakersafetyd; do
	ln -s /etc/init.d/"${rc##*/}" "$TMPDIR"/etc/runlevels/"$rc"
done

echo "preparing scripts for setup"
echo 'blacklist brcmfmac' >>  $TMPDIR/etc/modprobe.d/blacklist-brcmfmac.conf

cat > "$TMPDIR"/root/grub-setup.sh<<EOF
#!/bin/sh
mkinitfs
/usr/sbin/update-u-boot-asahi
grub-install --target=arm64-efi --efi-directory=/boot/efi --boot-directory=/boot --removable
grub-mkfont -s 24 -o /boot/grub/fonts/dejavu.pf2 usr/share/fonts/dejavu/DejaVuSansMono.ttf
grub-mkconfig  > /boot/grub/grub.cfg
exit
EOF

cat > "$TMPDIR"/etc/default/grub<<EOF
GRUB_DISTRIBUTOR="Alpine"
GRUB_TIMEOUT=10
GRUB_DISABLE_SUBMENU=y
GRUB_DISABLE_RECOVERY=true
GRUB_CMDLINE_LINUX="rootwait console=tty1"
GRUB_FONT="/boot/grub/fonts/dejavu.pf2"
EOF

chmod 0744 "$TMPDIR"/root/grub-setup.sh

echo "Settting grub boot loader"
mount -t proc none $TMPDIR/proc
mount -o bind /sys $TMPDIR/sys
mount -o bind /dev $TMPDIR/dev
chroot $TMPDIR /root/grub-setup.sh
#chroot $TMPDIR /bin/ash
umount $TMPDIR/dev
umount $TMPDIR/sys
umount $TMPDIR/proc
rm -rf alpine-installer/image
rm -rf alpine-installer/alpine-base.zip
mkdir -p alpine-installer/image
mkdir -p alpine-installer/image/esp/EFI/boot
mkdir -p alpine-installer/image/esp/m1n1

cp $TMPDIR/boot/efi/EFI/boot/BOOTAA64.EFI alpine-installer/image/esp/EFI/boot/
cp $TMPDIR/boot/efi/m1n1/boot.bin alpine-installer/image/esp/m1n1/
dd if="$ROOTDEV" of=alpine-installer/image/root.img
sed -i 's/^tty1.*/tty1::respawn:\/sbin\/agetty -L 115200 tty1 linux --login-pause --autologin root --noclear/' $TMPDIR/etc/inittab

echo "Finished, cleaning up"

cd alpine-installer/image
zip -r9 ../alpine-base.zip .