#!/usr/bin/env bash
set -euo pipefail

SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
# shellcheck source=00_env.sh
source "$SCRIPT_DIR/00_env.sh"

parse_common_args "$@"
require_inputs dg vol mount size

missing=0
for cmd in vxdg vxprint vxassist df findmnt; do
  require_cmd "$cmd" || missing=1
done

if (( missing != 0 )); then
  exit 2
fi

if [[ ! "$SIZE" =~ ^\+[0-9]+[KkMmGgTtPp]?$ ]]; then
  critical "invalid --size '$SIZE'; use a grow-by value such as +10G"
  exit 2
fi

status=0
vxdg list "$DISKGROUP" >/dev/null 2>&1 || { critical "diskgroup not found: $DISKGROUP"; status=1; }
vxprint -g "$DISKGROUP" "$VOLUME" >/dev/null 2>&1 || { critical "volume not found: $VOLUME"; status=1; }
findmnt --target "$MOUNTPOINT" >/dev/null 2>&1 || { critical "mountpoint is not mounted: $MOUNTPOINT"; status=1; }

if (( status != 0 )); then
  exit 1
fi

fs_type="$(findmnt --noheadings --output FSTYPE --target "$MOUNTPOINT" | awk 'NR == 1 {print $1}')"
device="$(findmnt --noheadings --output SOURCE --target "$MOUNTPOINT" | awk 'NR == 1 {print $1}')"
ok "filesystem type: ${fs_type:-unknown}"
ok "mounted device: ${device:-unknown}"

capture_cmd "Filesystem usage before expansion" df -h "$MOUNTPOINT"
capture_cmd "VxVM layout before volume expansion" vxprint -g "$DISKGROUP" -ht

confirm_execute "This will grow VxVM volume '$VOLUME' in diskgroup '$DISKGROUP' by '$SIZE'."
run_cmd "Grow VxVM volume by requested size" vxassist -g "$DISKGROUP" growby "$VOLUME" "$SIZE"

case "$fs_type" in
  vxfs)
    warning "VxFS fsadm syntax can vary by Veritas release and site standard"
    warning "manual filesystem resize recommended after volume growth; review a command such as: fsadm -F vxfs -b <new_size_or_supported_option> $MOUNTPOINT"
    ;;
  xfs)
    if has_cmd xfs_growfs; then
      run_cmd "Resize XFS filesystem online" xfs_growfs "$MOUNTPOINT"
    else
      critical "xfs_growfs not found; cannot resize XFS safely"
      exit 1
    fi
    ;;
  ext3|ext4)
    if has_cmd resize2fs; then
      if [[ -n "$device" ]]; then
        run_cmd "Resize ext filesystem" resize2fs "$device"
      else
        critical "unable to detect mounted device for resize2fs"
        exit 1
      fi
    else
      critical "resize2fs not found; cannot resize ext filesystem safely"
      exit 1
    fi
    ;;
  *)
    warning "unsupported or unknown filesystem type '$fs_type'; volume growth command was handled according to dry-run/execute mode"
    warning "manual filesystem resize required after confirming platform-specific procedure"
    ;;
esac

capture_cmd "Filesystem usage after expansion attempt" df -h "$MOUNTPOINT"
capture_cmd "VxVM layout after volume expansion attempt" vxprint -g "$DISKGROUP" -ht
ok "volume and filesystem expansion step completed"