#!/bin/bash

# Script to format /dev/sdb by removing LVM and creating a new filesystem.
# WARNING: This script will DELETE ALL DATA on /dev/sdb.

DEVICE="/dev/sdb"
PARTITION="${DEVICE}1"

# Function to check and ensure the script is run as root.
check_root() {
  if [[ $EUID -ne 0 ]]; then
    echo "This script must be run as root." >&2
    exit 1
  fi
}

# Confirm with the user before proceeding.
confirm_action() {
  read -p "WARNING: This will erase all data on $DEVICE. Are you sure? (yes/no): " CONFIRM
  if [[ "$CONFIRM" != "yes" ]]; then
    echo "Aborted."
    exit 0
  fi
}

# Deactivate logical volumes
deactivate_lvs() {
  echo "Deactivating logical volumes..."
  lvchange -an "$DEVICE"* 2>/dev/null
}

# Remove logical volumes
remove_lvs() {
  echo "Removing logical volumes..."
  lvremove -f "$(lvdisplay | grep 'LV Path' | awk '{print $3}')" 2>/dev/null || echo "No logical volumes found."
}

# Remove volume groups
remove_vgs() {
  echo "Removing volume groups..."
  vgremove -f "$(vgdisplay | grep 'VG Name' | awk '{print $3}')" 2>/dev/null || echo "No volume groups found."
}

# Remove physical volumes
remove_pvs() {
  echo "Removing physical volumes..."
  pvremove -ff "$DEVICE" 2>/dev/null || echo "No physical volumes found on $DEVICE."
}

# Wipe the partition
wipe_partition() {
  echo "Wiping $DEVICE..."
  wipefs -a "$DEVICE"
  dd if=/dev/zero of="$DEVICE" bs=1M status=progress count=100
}

# Create a new partition and format
create_partition() {
  echo "Creating a new partition table..."
  parted "$DEVICE" mklabel gpt --script
  parted "$DEVICE" mkpart primary ext4 0% 100% --script

  echo "Formatting the new partition with ext4..."
  mkfs.ext4 "$PARTITION"
}

# Main execution
main() {
  check_root
  confirm_action
  deactivate_lvs
  remove_lvs
  remove_vgs
  remove_pvs
  wipe_partition
  ##create_partition

  echo "Operation completed. $PARTITION is now formatted and ready for use."
}

# Run the main function
main