#!/bin/sh
set -eu

cd "$(dirname "$0")/.."

if ! command -v docker >/dev/null 2>&1; then
  echo "Docker Engine is required" >&2
  exit 2
fi

IMAGE="${IDS_MIGRATION_IMAGE:-routeros-suricata-tzsp:local}"
TARGET_VOLUME="${IDS_DATA_VOLUME:-routeros-suricata-data}"

docker volume create "$TARGET_VOLUME" >/dev/null

target_is_empty() {
  subpath="$1"
  docker run --rm --entrypoint /bin/sh \
    -v "${TARGET_VOLUME}:/target" \
    "$IMAGE" \
    -c "test ! -d '/target/${subpath}' || test -z \"\$(find '/target/${subpath}' -mindepth 1 -maxdepth 1 -print -quit 2>/dev/null)\""
}

copy_host_dir() {
  source_dir="$1"
  target_subpath="$2"
  label="$3"

  if [ ! -d "$source_dir" ] || [ -z "$(find "$source_dir" -mindepth 1 -maxdepth 1 -print -quit 2>/dev/null)" ]; then
    echo "[volume-migration] no legacy ${label} data in ${source_dir}; skipping"
    return 0
  fi
  if ! target_is_empty "$target_subpath"; then
    echo "[volume-migration] /data/${target_subpath} is not empty; leaving it unchanged"
    return 0
  fi

  source_abs="$(cd "$source_dir" && pwd)"
  docker run --rm --entrypoint /bin/sh \
    -v "${source_abs}:/legacy:ro" \
    -v "${TARGET_VOLUME}:/target" \
    "$IMAGE" \
    -c "set -eu; mkdir -p '/target/${target_subpath}'; cp -a /legacy/. '/target/${target_subpath}/'"
  echo "[volume-migration] migrated ${label}: ${source_dir} -> ${TARGET_VOLUME}:/${target_subpath}"
}

copy_named_volume() {
  source_volume="$1"
  target_subpath="$2"
  label="$3"

  if ! docker volume inspect "$source_volume" >/dev/null 2>&1; then
    return 0
  fi
  if ! target_is_empty "$target_subpath"; then
    echo "[volume-migration] /data/${target_subpath} is not empty; leaving legacy ${source_volume} unchanged"
    return 0
  fi

  docker run --rm --entrypoint /bin/sh \
    -v "${source_volume}:/legacy:ro" \
    -v "${TARGET_VOLUME}:/target" \
    "$IMAGE" \
    -c "set -eu; if [ -n \"\$(find /legacy -mindepth 1 -maxdepth 1 -print -quit 2>/dev/null)\" ]; then mkdir -p '/target/${target_subpath}'; cp -a /legacy/. '/target/${target_subpath}/'; fi"
  echo "[volume-migration] merged ${label}: ${source_volume} -> ${TARGET_VOLUME}:/${target_subpath}"
}

# <=0.6.1 host bind directories. Application data stays at /data root to
# preserve ids.db and redis paths; logs/rules are folded into subdirectories.
if target_is_empty ""; then
  copy_host_dir "data" "" "SQLite/Redis/application"
else
  echo "[volume-migration] ${TARGET_VOLUME} already contains application data; keeping it"
fi
copy_host_dir "logs" "logs/suricata" "Suricata logs"
copy_host_dir "data/vendor-rules" "lib/suricata" "vendor rules"

# 0.7.0 used three named volumes. Merge the two auxiliary volumes into the
# single data volume without overwriting newer files.
copy_named_volume "routeros-suricata-logs" "logs/suricata" "Suricata logs"
copy_named_volume "routeros-suricata-rules" "lib/suricata" "Suricata rule state"