#!/bin/ash

backup_dir="."
overlay_dir="/overlay"

while true; do
    echo ""
    echo "请选择操作:"
    echo "1. 备份 /overlay 目录"
    echo "2. 还原 /overlay 目录"
    echo "q. 退出脚本"

    read -rp "请输入选项 (1/2/q): " choice

    case "$choice" in
        1)
            backup_file="${backup_dir}/backup_$(date +%Y-%m-%d).tar.gz"
            echo "正在备份 $overlay_dir 到 $backup_file..."
            if tar -czvf "$backup_file" "$overlay_dir"; then
                sync
                echo "✅ 备份成功: $backup_file"
            else
                echo "❌ 备份失败: 无法创建备份文件"
            fi
            ;;
        2)
            echo "扫描可用备份文件..."
            set -- "${backup_dir}"/backup_*.tar.gz
            [ -e "$1" ] || {
                echo "❌ 没有找到可用的备份文件！"
                continue
            }

            index=1
            for file in "$@"; do
                echo "$index) $(basename "$file")"
                eval "backup_$index=\"$file\""
                index=$((index+1))
            done

            read -rp "请输入要还原的备份编号: " selection
            eval "selected_file=\${backup_$selection}"

            if [ -z "$selected_file" ] || [ ! -f "$selected_file" ]; then
                echo "❌ 无效编号，返回主菜单。"
                continue
            fi

            echo "正在还原 $selected_file 到根目录..."
            if tar -xzvf "$selected_file" -C /; then
                sync
                echo "✅ 还原成功！"
            else
                echo "❌ 还原失败: 解压过程中出错"
            fi
            ;;
        q)
            echo "👋 已退出脚本。"
            break
            ;;
        *)
            echo "❌ 无效选项，请重新输入。"
            ;;
    esac
done