#!/usr/bin/env bash
export DISK_IMAGE="$2"
export ROOT_MOUNT="$OPUS_OUTPUT/mount"

# Get the approximate size required for the image
export DISK_SIZE=$(du -sb "$1" | cut -f1)
# Add 256MB for SWAP, and 700MB for overhead
export DISK_SIZE=$(( $DISK_SIZE + ( 256 * 1000000 ) + ( 700 * 1000000 ) ))
# Add size of additional files
export DISK_SIZE=$(( $DISK_SIZE + $(du -sb "$OPUS_HOME/input/root-image" | cut -f1) ))

# Create and mount disk
fallocate -l $DISK_SIZE "$DISK_IMAGE"
export DISK_LOOP="$(losetup --show -f -P "$DISK_IMAGE")"

# Partition disk
(
echo n
echo e
echo 
echo 
echo +256M
echo t
echo swap
echo n
echo p
echo 
echo 
echo 
echo t
echo 
echo linux
echo w
echo 
echo 
) | fdisk "$DISK_LOOP"

# Format partions
mkswap "${DISK_LOOP}p1"
mkfs.ext4 "${DISK_LOOP}p2"

# Mount root
mkdir "$ROOT_MOUNT"
mount "${DISK_LOOP}p2" "$ROOT_MOUNT"

# Add files
dupe "$1/." "$ROOT_MOUNT"

# Make fstab
echo "UUID=$(blkid -o value -s UUID "${DISK_LOOP}p1") none swap sw 0 0" >"$ROOT_MOUNT/etc/fstab"
echo "UUID=$(blkid -o value -s UUID "${DISK_LOOP}p2") / ext4 errors=remount-ro 0 1" >>"$ROOT_MOUNT/etc/fstab"

# Set up GRUB and misc
fchroot "$ROOT_MOUNT" "/setupdisk"

# Clear logs
find "$ROOT_MOUNT/var/log" -type f -delete

# Unmount root
umount -l "$ROOT_MOUNT"
rmdir "$ROOT_MOUNT"
losetup -d "$DISK_LOOP"