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

# Move large legacy folders from local disk to NAS with verification-friendly flow.
# Default mode is DRY-RUN.
#
# Examples:
#   scripts/ops/netgescon-move-to-nas.sh \
#     --nas-root /mnt/nas_netgescon/migrazioni-locali \
#     --source /home/michele/backup-completo \
#     --source /var/www/netgescon_OLD
#
#   scripts/ops/netgescon-move-to-nas.sh \
#     --nas-root /mnt/nas_netgescon/migrazioni-locali \
#     --source /home/michele/backup-completo \
#     --apply --purge-source

NAS_ROOT="/mnt/nas_netgescon/migrazioni-locali"
APPLY="no"
PURGE_SOURCE="no"
TS="$(date +%Y%m%d-%H%M%S)"
LOG_DIR="/tmp/netgescon-nas-move-${TS}"
declare -a SOURCES=()

die() {
  echo "Error: $*" >&2
  exit 1
}

usage() {
  cat <<'EOF'
Usage:
  netgescon-move-to-nas.sh --source <path> [--source <path> ...] [options]

Options:
  --source <path>       Source directory to move/copy (can be used multiple times)
  --nas-root <path>     NAS base destination (default: /mnt/nas_netgescon/migrazioni-locali)
  --apply               Execute real copy (default: dry-run)
  --purge-source        Remove source after successful copy (only with --apply)
  -h, --help            Show this help
EOF
}

while [[ $# -gt 0 ]]; do
  case "$1" in
    --source)
      SOURCES+=("$2")
      shift 2
      ;;
    --nas-root)
      NAS_ROOT="$2"
      shift 2
      ;;
    --apply)
      APPLY="yes"
      shift
      ;;
    --purge-source)
      PURGE_SOURCE="yes"
      shift
      ;;
    -h|--help)
      usage
      exit 0
      ;;
    *)
      usage
      die "Unknown option: $1"
      ;;
  esac
done

[[ ${#SOURCES[@]} -gt 0 ]] || { usage; die "At least one --source is required"; }
[[ -d "$NAS_ROOT" ]] || die "NAS root not found/mounted: $NAS_ROOT"

if [[ "$PURGE_SOURCE" == "yes" && "$APPLY" != "yes" ]]; then
  die "--purge-source requires --apply"
fi

mkdir -p "$LOG_DIR"

echo "== NetGescon NAS Move =="
echo "Mode: $( [[ "$APPLY" == "yes" ]] && echo "APPLY" || echo "DRY-RUN" )"
echo "Purge source after copy: $PURGE_SOURCE"
echo "NAS root: $NAS_ROOT"
echo "Log dir: $LOG_DIR"
echo

run_rsync() {
  local src="$1"
  local dst="$2"

  local -a args=(
    -a
    --human-readable
    --info=stats2,name0
    --no-owner
    --no-group
  )

  if [[ "$APPLY" != "yes" ]]; then
    args+=(--dry-run)
  fi

  rsync "${args[@]}" "$src/" "$dst/"
}

for src in "${SOURCES[@]}"; do
  [[ -d "$src" ]] || { echo "Skip missing source: $src"; continue; }

  src_abs="$(readlink -f "$src")"
  src_name="$(basename "$src_abs")"
  src_parent_name="$(basename "$(dirname "$src_abs")")"
  dst="$NAS_ROOT/${src_parent_name}/${src_name}"
  mkdir -p "$dst"

  echo "------------------------------------------------------------"
  echo "Source: $src_abs"
  echo "Dest:   $dst"

  echo "[1/3] Size source"
  du -sh "$src_abs" || true

  echo "[2/3] Rsync"
  run_rsync "$src_abs" "$dst" | tee "$LOG_DIR/${src_name}.log"

  if [[ "$APPLY" == "yes" ]]; then
    echo "[3/3] Verify destination size"
    du -sh "$dst" || true

    if [[ "$PURGE_SOURCE" == "yes" ]]; then
      echo "[PURGE] Removing source: $src_abs"
      rm -rf "$src_abs"
    fi
  fi

  echo "Done: $src_abs"
  echo

done

echo "All tasks completed."
echo "Logs: $LOG_DIR"