#!/bin/sh

set -euo pipefail
[ "$(id -u)" -eq 0 ] || { echo "This script must be run as root." >&2; exit 1; }

apk add parted btrfs-progs dhcpcd

DISK=""
SEPARATE_HOME="no"
SECURE_BOOT="no"

usage() {
    cat <<EOF
Usage: $0 -d <disk> [-H] [-s]
  -d <disk>   Target disk device (e.g. /dev/sda or /dev/nvme0n1)
  -H          Create separate /home partition
EOF
    exit 1
}

while getopts "d:Hs" opt; do
    case "$opt" in
        d) DISK="$OPTARG" ;; H) SEPARATE_HOME="yes" ;; *) usage ;;
    esac
done
[ -n "$DISK" ] || usage

dhcpcd || true
sleep 10

UEFI="no"
if [ -d /sys/firmware/efi ]; then
    UEFI="yes"
fi

echo "Installing on $DISK (UEFI: $UEFI, Separate /home: $SEPARATE_HOME, SecureBoot: $SECURE_BOOT)"

if echo "$DISK" | grep -qE "^/dev/nvme"; then
    PART1=p1; PART2=p2; PART3=p3; PART4=p4
else
    PART1=1; PART2=2; PART3=3; PART4=4
fi
EFI_PART=${DISK}${PART1}
ROOT_PART=${DISK}${PART2}
HOME_PART=${DISK}${PART3}
BIOS_PART=${DISK}${PART4}

echo "Partitioning $DISK..."
parted -s "$DISK" mklabel gpt
if [ "$UEFI" = "yes" ]; then
    parted -s "$DISK" mkpart primary fat32 1MiB 513MiB
    parted -s "$DISK" name 1 EFI
    parted -s "$DISK" set 1 esp on
    parted -s "$DISK" mkpart primary btrfs 513MiB 100%
    parted -s "$DISK" name 2 ROOT
    if [ "$SEPARATE_HOME" = "yes" ]; then
        parted -s "$DISK" mkpart primary btrfs 90% 100%
        parted -s "$DISK" name 3 HOME
    fi
else
    parted -s "$DISK" mkpart primary 1MiB 3MiB
    parted -s "$DISK" name 1 BIOS
    parted -s "$DISK" set 1 bios_grub on
    parted -s "$DISK" mkpart primary btrfs 3MiB 100%
    parted -s "$DISK" name 2 ROOT
    if [ "$SEPARATE_HOME" = "yes" ]; then
        parted -s "$DISK" mkpart primary btrfs 80% 100%
        parted -s "$DISK" name 3 HOME
    fi
fi

mkfs.vfat -F32 -n EFI "$EFI_PART" || true
mkfs.btrfs -f -L ROOT "$ROOT_PART"
if [ "$SEPARATE_HOME" = "yes" ]; then
    mkfs.btrfs -f -L HOME "$HOME_PART"
fi

TARGET=/mnt/panora
mkdir -p $TARGET
mount -t btrfs -o defaults "$ROOT_PART" $TARGET
mkdir -p $TARGET/boot
mount -t vfat "$EFI_PART" $TARGET/boot

umount $TARGET/boot; umount $TARGET
mount -t btrfs -o subvolid=5,defaults "$ROOT_PART" $TARGET
btrfs subvolume create $TARGET/@
btrfs subvolume create $TARGET/@var
[ "$SEPARATE_HOME" = "no" ] && btrfs subvolume create $TARGET/@home
umount $TARGET
mount -t btrfs -o subvol=@ "$ROOT_PART" $TARGET
mkdir -p $TARGET/var
mount -t btrfs -o subvol=@var "$ROOT_PART" $TARGET/var
mkdir -p $TARGET/home
if [ "$SEPARATE_HOME" = "no" ]; then
    mount -t btrfs -o subvol=@home "$ROOT_PART" $TARGET/home
else
    mount -t btrfs "$HOME_PART" $TARGET/home
fi
mkdir -p $TARGET/boot
mount -t vfat "$EFI_PART" $TARGET/boot

ip route
echo "-> Testing network connectivity"
ping -c 3 1.1.1.1 || { echo "ERROR: Network connection failed"; exit 1; }

setup-apkrepos -1 -c
apk update
apk add alpine-make-rootfs
alpine-make-rootfs -p alpine-base -p dhcpcd -r /etc/apk/repositories $TARGET

mount --rbind /dev $TARGET/dev
mount --rbind /sys $TARGET/sys
mount --rbind /proc $TARGET/proc
cp /etc/resolv.conf $TARGET/etc/
chroot $TARGET /bin/sh <<EOF
set -euo pipefail
setup-apkrepos -f -c
apk update
echo panora > /etc/hostname
apk add dhcpcd
rc-update add dhcpcd default
apk add btrfs-progs kmod linux-lts
echo btrfs >> /etc/modules
KERNEL_VER=\$(basename /lib/modules/*)
modprobe -S \$KERNEL_VER btrfs
ROOT_UUID=$(blkid $ROOT_PART | grep -o 'UUID="[^"]*"' | cut -d'"' -f2)
EFI_UUID=$(blkid $EFI_PART | grep -o 'UUID="[^"]*"' | cut -d'"' -f2)
echo "UUID=\$ROOT_UUID / btrfs defaults,subvol=@ 0 0" > /etc/fstab
[ "$SEPARATE_HOME" = "yes" ] && HOME_UUID=$(blkid $HOME_PART | grep -o 'UUID="[^"]*"' | cut -d'"' -f2) && echo "UUID=\$HOME_UUID /home btrfs defaults 0 2" >> /etc/fstab || echo "UUID=\$ROOT_UUID /home btrfs defaults,subvol=@home 0 0" >> /etc/fstab
echo "UUID=\$EFI_UUID /boot vfat defaults 0 2" >> /etc/fstab
echo "tmpfs /tmp tmpfs defaults,noatime 0 0" >> /etc/fstab
apk add mkinitfs
echo 'features="ata base cdrom keymap kms mmc nvme raid scsi usb virtio btrfs"' > /etc/mkinitfs/mkinitfs.conf
mkinitfs -o /boot/initramfs-lts -l \$KERNEL_VER -c /etc/mkinitfs/mkinitfs.conf -b /
rc-update add btrfs-scan boot
apk add grub-efi efibootmgr grub grub-bios
if [ "$UEFI" = "yes" ]; then
    grub-install --target=x86_64-efi --efi-directory=/boot --bootloader-id=Panora
else
    grub-install --target=i386-pc --recheck "$DISK"
fi
echo "GRUB_TIMEOUT=5
GRUB_DISTRIBUTOR="Panora"
GRUB_CMDLINE_LINUX="debug_init single"
GRUB_CMDLINE_LINUX_DEFAULT="rootfstype=btrfs"
grub-mkconfig -o /boot/grub/grub.cfg" >> /etc/default/grub

EOF

echo "Installation complete. Reboot now."