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

TIMESTAMP="${TIMESTAMP:-$(date +%Y%m%d_%H%M%S)}"
DRY_RUN="${DRY_RUN:-true}"
LOG_FILE="${LOG_FILE:-/tmp/gpfs_extend_${TIMESTAMP}.log}"

FILESYSTEM="${FILESYSTEM:-}"
NSD_STANZA="${NSD_STANZA:-}"
FAILURE_GROUP="${FAILURE_GROUP:-}"
STORAGE_POOL="${STORAGE_POOL:-system}"
USAGE="${USAGE:-dataAndMetadata}"

log() {
  local level="$1"
  shift
  local message="$*"

  printf '%s: %s\n' "$level" "$message" | tee -a "$LOG_FILE"
}

ok() {
  log "OK" "$@"
}

warning() {
  log "WARNING" "$@"
}

critical() {
  log "CRITICAL" "$@"
}

require_cmd() {
  local cmd="$1"

  if command -v "$cmd" >/dev/null 2>&1; then
    ok "Command available: $cmd"
    return 0
  fi

  critical "Required command not found: $cmd"
  return 1
}

validate_gpfs_command() {
  local cmd="$1"

  if command -v "$cmd" >/dev/null 2>&1; then
    return 0
  fi

  warning "GPFS command not available, skipping: $cmd"
  return 1
}

run_cmd() {
  if [[ "$#" -eq 0 ]]; then
    critical "run_cmd called without a command"
    return 2
  fi

  if [[ "$DRY_RUN" == "true" ]]; then
    log "OK" "DRY-RUN: $*"
    return 0
  fi

  log "OK" "RUN: $*"
  "$@" 2>&1 | tee -a "$LOG_FILE"
}

run_readonly() {
  if [[ "$#" -eq 0 ]]; then
    critical "run_readonly called without a command"
    return 2
  fi

  log "OK" "READ-ONLY: $*"
  "$@" 2>&1 | tee -a "$LOG_FILE"
}

confirm_execute() {
  local target="${1:-GPFS change}"

  if [[ "$DRY_RUN" == "true" ]]; then
    ok "Dry-run mode enabled. No changes will be made."
    return 0
  fi

  warning "Execution mode requested for: $target"
  warning "Coordinate this change with storage, GPFS, application, and change-management teams."
  printf 'Type EXECUTE to continue: '
  read -r confirmation

  if [[ "$confirmation" != "EXECUTE" ]]; then
    critical "Confirmation failed. Aborting."
    exit 1
  fi

  ok "Execution confirmed by operator."
}

usage_value_valid() {
  case "$1" in
    dataOnly|metadataOnly|dataAndMetadata) return 0 ;;
    *) return 1 ;;
  esac
}

section() {
  printf '\n== %s ==\n' "$1" | tee -a "$LOG_FILE"
}