#!/usr/bin/env sh
set -eu
image="${1:?Usage: restore.sh IMAGE VOLUME BACKUP_FILE}"
volume="${2:?VOLUME required}"
backup="${3:?BACKUP_FILE required}"
[ -f "$backup" ] || { echo 'Backup file missing' >&2; exit 1; }
backup="$(cd "$(dirname "$backup")" && pwd)/$(basename "$backup")"
# Named volumes only. All users must remain stopped for the whole operation.
docker volume inspect "$volume" >/dev/null
active="$(docker ps -q --filter "volume=$volume")"
[ -z "$active" ] || { echo 'Stop every container using the volume before restore' >&2; exit 1; }
helper="evofw-restore-$(date +%s)-$$"
cleanup() {
  result=$?
  trap - EXIT HUP INT TERM
  # -v removes anonymous helper volumes only, never the target named volume.
  docker rm -fv "$helper" >/dev/null 2>&1 || true
  exit "$result"
}
trap cleanup EXIT
trap 'exit 129' HUP
trap 'exit 130' INT
trap 'exit 143' TERM
# Transfer input through the Docker API, including when its daemon is remote.
docker create --name "$helper" --network none --cap-drop ALL \
  --security-opt no-new-privileges:true --mount "type=volume,src=$volume,dst=/data" \
  --entrypoint node "$image" tools/sqlite-backup.mjs restore /tmp/evofw-restore-input.db /data/app.db --offline >/dev/null
docker cp "$backup" "$helper:/tmp/evofw-restore-input.db"
active="$(docker ps -q --filter "volume=$volume")"
[ -z "$active" ] || { echo 'Target volume became active before restore; helper was not started' >&2; exit 1; }
docker start --attach "$helper"
result="$(docker wait "$helper")"
case "$result" in ''|*[!0-9]*) echo 'Invalid restore container exit status' >&2; exit 1;; esac
[ "$result" -le 255 ] || { echo 'Invalid restore container exit status' >&2; exit 1; }
exit "$result"