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

# Dify docker backup script
# 备份内容：
#   1) Postgres 数据库 dify
#   2) 整个 volumes/ 目录（包括插件、向量库等数据）

SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
cd "$SCRIPT_DIR"

BACKUP_DIR="$SCRIPT_DIR/backups"
TIMESTAMP="$(date +%Y%m%d_%H%M%S)"
DB_FILE="$BACKUP_DIR/dify_db_${TIMESTAMP}.sql"
VOL_FILE="$BACKUP_DIR/dify_volumes_${TIMESTAMP}.tar.gz"

mkdir -p "$BACKUP_DIR"

DB_USER="${POSTGRES_USER:-postgres}"
DB_NAME="${POSTGRES_DB:-dify}"

# 自动检测 db_postgres 容器名，匹配形如 "<project>-db_postgres-1"
DB_CONTAINER="${DB_CONTAINER:-}"
if [ -z "$DB_CONTAINER" ]; then
  DB_CONTAINER="$(docker ps --format '{{.Names}}' | grep 'db_postgres-1$' | head -n1 || true)"
fi

if [ -z "$DB_CONTAINER" ]; then
  echo "错误：未找到名称类似 '*-db_postgres-1' 的运行中容器，请确认 db_postgres 服务已启动。" >&2
  exit 1
fi

echo "[1/2] 导出 Postgres 数据库 ${DB_NAME} (容器: ${DB_CONTAINER}) ..."

docker exec -t "${DB_CONTAINER}" \
  pg_dump -U "${DB_USER}" -d "${DB_NAME}" > "${DB_FILE}"

echo "数据库已备份到: ${DB_FILE}"

echo "[2/2] 打包 volumes/ 目录 ..."
if [ ! -d "volumes" ]; then
  echo "警告：当前目录下不存在 volumes/ 目录，跳过卷备份。" >&2
else
  tar czf "${VOL_FILE}" volumes/
  echo "卷数据已打包到: ${VOL_FILE}"
fi

echo "备份完成。"