#!/bin/ash

LOG_FILE="/tmp/pre-mount-fixinst.log"
# Initialize log
rm -f "$LOG_FILE" >/dev/null 2>&1
touch "$LOG_FILE"
# Redirect all output (stdout and stderr) to the log file
exec >>"$LOG_FILE" 2>&1

mount_factory() {
    # Redirect all output (stdout and stderr) to the log file
    exec >>"$LOG_FILE" 2>&1
    
    # Check if /real_rootfs exists
    if [ ! -d "/real_rootfs" ]; then
        echo "Error: /real_rootfs does not exist. Cannot proceed with stop." >> "$LOG_FILE"
        return 1
    fi

    # Determine firmware version based on mounts
    if [ -d "/usrdata" ] && [ -d "/systemrw" ]; then
        echo "New firmware scenario detected (with /usrdata and /systemrw)." >> "$LOG_FILE"
        stop_handle_new_firmware
    else
        echo "Old firmware scenario detected (without /usrdata and /systemrw)." >> "$LOG_FILE"
        stop_handle_old_firmware
    fi
}

stop_handle_new_firmware() {
    # Redirect all output (stdout and stderr) to the log file
    exec >>"$LOG_FILE" 2>&1
    /bin/echo "Stopping and reverting overlay and pivot_root"
    service init-overlay-watchdog stop
    service init-overlay-watchdog disable
    # Unmount /etc/rc.d bind
    /bin/umount -lf /etc/rc.d
    # Remount the original root filesystem as read-write
    /bin/mount -o remount,rw /real_rootfs

    # Move the mounted filesystems back to the original locations
    /bin/mount --move /sys /real_rootfs/sys
    /bin/mount --move /proc /real_rootfs/proc
    /bin/mount --move /tmp /real_rootfs/tmp
    /bin/mount --move /dev /real_rootfs/dev
    /bin/mount --move /firmware /real_rootfs/firmware
    /bin/mount --move /usrdata /real_rootfs/usrdata
    /bin/mount --move /data /real_rootfs/data
    /bin/mount --move /cache /real_rootfs/cache
    /bin/mount --move /systemrw /real_rootfs/systemrw
    /bin/mount --move /persist /real_rootfs/persist

    # Pivot root back to the original root
    /sbin/pivot_root /real_rootfs /real_rootfs/rootfs

    /bin/echo "Reverted pivot_root"
	
	# Unmount /rootfs overlay
	/bin/umount -lf /rootfs >/dev/null 2>&1
    service init-overlay-watchdog disable
	
	# Mount layer 2 /etc back
    /bin/mount --bind /usrdata/etc /etc
    service init-overlay-watchdog disable

    # Mount layer 3 /etc back
    /bin/mount -t overlay overlay -o lowerdir=/etc,upperdir=/usrdata/overlay-work/etc-upper,workdir=/usrdata/overlay-work/.etc-work /etc
    service init-overlay-watchdog disable
	df -h
	echo -e "\e[31m / is read-write right now. Be careful\e[0m"
	echo -e "\e[31m Reboot or run mount -o remount,ro / \e[0m"
}

stop_handle_old_firmware() {
    # Redirect all output (stdout and stderr) to the log file
    exec >>"$LOG_FILE" 2>&1
    /bin/echo "Stopping and reverting overlay and pivot_root" 
    service init-overlay-watchdog stop
    service init-overlay-watchdog disable
    # Unmount /etc/rc.d bind
    /bin/umount -lf /etc/rc.d

    # Remount the original root filesystem as read-write
    /bin/mount -o remount,rw /real_rootfs

    # Move the mounted filesystems back to the original locations
    /bin/mount --move /sys /real_rootfs/sys 
    /bin/mount --move /proc /real_rootfs/proc 
    /bin/mount --move /tmp /real_rootfs/tmp 
    /bin/mount --move /dev /real_rootfs/dev 
    /bin/mount --move /firmware /real_rootfs/firmware 
    /bin/mount --move /persist /real_rootfs/persist 
    /bin/mount --move /cache /real_rootfs/cache 
    /bin/mount --move /data /real_rootfs/data 

    # Pivot root back to the original root
    /sbin/pivot_root /real_rootfs /real_rootfs/rootfs 

    /bin/echo "Reverted pivot_root"
	
	# Unmount /rootfs overlay
	/bin/umount -lf /rootfs >/dev/null 2>&1
	
	# Mount the location of etc-upper back
	mount -t ubifs /dev/ubi0_3 /overlay
	
	# Mount the old overlay filesystem back for etc
    /bin/mount -t overlay overlay -o lowerdir=/etc,upperdir=/overlay/etc-upper,workdir=/overlay/.etc-work /etc 
	
	echo -e "\e[31m / is read-write right now. Be careful\e[0m"
	echo -e "\e[31m Reboot or run mount -o remount,ro / \e[0m"
}


if grep -qs '/real_rootfs' /proc/mounts; then
    echo "Upgrade scenario detected."
    mount_factory
    service mount-fix disable
    echo "Filesystem structure returned to Quectel Stock"
    echo "Backup exists at /usrdata/rootfs or /data/rootfs"
fi

# Remount original rootfs as read-write 
echo "Mounting / as read-write"
mount -o remount,rw /

# Check if /etc is mounted
if grep -qs '/etc' /proc/mounts; then
    echo "Unmounting /etc..."
    umount -lf /etc
fi

# Check if /usrdata is mounted
if grep -qs '/usrdata' /proc/mounts; then
    echo "/usrdata is mounted. Unmounting /etc again to access rootfs /etc..."
    umount -lf /etc
fi

echo "Preinst complete...."
echo "View Results here:..."
mount

exit 0