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

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

REPORT_FILE=""

usage() {
  printf 'Usage: %s --fs <filesystem>\n' "$(basename "$0")"
}

while [[ "$#" -gt 0 ]]; do
  case "$1" in
    --fs) FILESYSTEM="${2:-}"; shift 2 ;;
    -h|--help) usage; exit 0 ;;
    *) critical "Unknown argument: $1"; usage; exit 2 ;;
  esac
done

if [[ -z "$FILESYSTEM" ]]; then
  critical "Missing required --fs <filesystem>"
  usage
  exit 2
fi

REPORT_FILE="/tmp/gpfs_extend_report_${FILESYSTEM}_${TIMESTAMP}.txt"

append_section() {
  local title="$1"
  shift

  {
    printf '\n== %s ==\n' "$title"
    if command -v "$1" >/dev/null 2>&1; then
      "$@" 2>&1 || printf 'WARNING: command failed: %s\n' "$*"
    else
      printf 'WARNING: command not available: %s\n' "$1"
    fi
  } >> "$REPORT_FILE"
}

{
  printf 'GPFS / Spectrum Scale Filesystem Expansion Report\n'
  printf 'Hostname: %s\n' "$(hostname 2>/dev/null || printf 'unknown')"
  printf 'Date: %s\n' "$(date)"
  printf 'Target filesystem: %s\n' "$FILESYSTEM"
} > "$REPORT_FILE"

append_section "GPFS daemon state" mmgetstate -a
append_section "Cluster definition" mmlscluster
append_section "Managers and quorum" mmlsmgr
append_section "Target filesystem mount state" mmlsmount "$FILESYSTEM"
append_section "Target filesystem disks" mmlsdisk "$FILESYSTEM"
append_section "NSD inventory" mmlsnsd
append_section "Filesystem capacity" df -h

if command -v mmhealth >/dev/null 2>&1; then
  append_section "Cluster health" mmhealth cluster show
else
  printf '\n== Cluster health ==\nWARNING: mmhealth command not available\n' >> "$REPORT_FILE"
fi

if command -v journalctl >/dev/null 2>&1; then
  append_section "Recent GPFS journal entries" journalctl -u 'gpfs*' -n 50 --no-pager
fi

if command -v dmesg >/dev/null 2>&1; then
  {
    printf '\n== Recent kernel messages ==\n'
    dmesg -T 2>/dev/null | tail -50 || printf 'WARNING: dmesg query failed\n'
  } >> "$REPORT_FILE"
fi

ok "Generated report: $REPORT_FILE"