#!/bin/bash
# tver DB復元確認（Synology ds923pで手動実行）
#
# 配置先: /volume1/docker/tver-db/restore-test.sh
# 実行コマンド: bash /volume1/docker/tver-db/restore-test.sh
# 最新のバックアップを同じPostgreSQLコンテナ内の一時DBへ復元し、主要4表の
# 行数を本番DBと比較する。本番DBにはSELECTだけを実行する。

set -euo pipefail

BACKUP_DIR="${BACKUP_DIR:-/volume1/backups/tver}"
LOG_FILE="${LOG_FILE:-${BACKUP_DIR}/restore-test.log}"
CONTAINER="${CONTAINER:-tver-postgres}"
DB_USER="${DB_USER:-tver}"
DB_NAME="${DB_NAME:-tver}"
RESTORE_DB="${RESTORE_DB:-tver_restore_test}"
DOCKER="${DOCKER:-$(command -v docker || printf '/usr/local/bin/docker')}"
TABLES=(download_jobs subscriptions known_episodes schema_migrations)

mkdir -p "$BACKUP_DIR"
touch "$LOG_FILE"
chmod 600 "$LOG_FILE"
exec > >(tee -a "$LOG_FILE") 2>&1

if [[ "$RESTORE_DB" == "$DB_NAME" ]]; then
  echo "ERROR: RESTORE_DB must differ from DB_NAME" >&2
  exit 1
fi

# 終了状態にかかわらず、一時DBの削除を最後に試みる。
cleanup() {
  status=$?
  trap - EXIT
  set +e
  "$DOCKER" exec "$CONTAINER" dropdb --force --if-exists -U "$DB_USER" "$RESTORE_DB"
  cleanup_status=$?
  if ((status != 0)); then
    echo "復元確認に失敗"
    exit "$status"
  fi
  exit "$cleanup_status"
}
trap cleanup EXIT

LATEST="$(find "$BACKUP_DIR" -name 'tver_*.sql.gz' -type f -print | sort | tail -n 1)"
if [[ -z "$LATEST" ]]; then
  echo "ERROR: backup dump was not found in $BACKUP_DIR" >&2
  exit 1
fi

echo "復元確認を開始: $LATEST"
"$DOCKER" exec "$CONTAINER" dropdb --force --if-exists -U "$DB_USER" "$RESTORE_DB"
"$DOCKER" exec "$CONTAINER" createdb -U "$DB_USER" "$RESTORE_DB"

gzip -dc "$LATEST" \
  | "$DOCKER" exec -i "$CONTAINER" psql -q -o /dev/null -v ON_ERROR_STOP=1 -U "$DB_USER" -d "$RESTORE_DB"

for table in "${TABLES[@]}"; do
  query="SELECT count(*) FROM public.${table};"
  production_count="$("$DOCKER" exec "$CONTAINER" psql -A -t -q -U "$DB_USER" -d "$DB_NAME" -c "$query" | tr -d '[:space:]')"
  restored_count="$("$DOCKER" exec "$CONTAINER" psql -A -t -q -U "$DB_USER" -d "$RESTORE_DB" -c "$query" | tr -d '[:space:]')"
  if [[ ! "$production_count" =~ ^[0-9]+$ || ! "$restored_count" =~ ^[0-9]+$ ]]; then
    echo "ERROR: $table の行数を取得できませんでした: production=$production_count restore=$restored_count" >&2
    exit 1
  fi
  if [[ "$production_count" != "$restored_count" ]]; then
    echo "ERROR: $table の行数が一致しません: production=$production_count restore=$restored_count" >&2
    exit 1
  fi
  echo "OK: $table production=$production_count restore=$restored_count"
done

echo "復元確認に成功: $LATEST"