#!/bin/bash

# FTP备份脚本
# 用法: ./ftp_backup.sh -p密码 目录1 目录2 目录3 文件1

set -e  # 遇到错误立即退出

# 配置信息（请根据实际情况修改）
FTP_SERVER="ftp.example.com"
FTP_PORT="21"
FTP_USER="username"
BACKUP_PREFIX="backup"
REMOTE_PATH="/backups"

# 颜色输出
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
NC='\033[0m' # No Color

log() {
    echo -e "${GREEN}[$(date +'%Y-%m-%d %H:%M:%S')] $1${NC}"
}

warn() {
    echo -e "${YELLOW}[$(date +'%Y-%m-%d %H:%M:%S')] 警告: $1${NC}"
}

error() {
    echo -e "${RED}[$(date +'%Y-%m-%d %H:%M:%S')] 错误: $1${NC}" >&2
    exit 1
}

# 显示用法信息
usage() {
    echo "用法: $0 -p密码 目录1 目录2 目录3 文件1"
    echo "选项:"
    echo "  -p密码     FTP密码（包含特殊字符时请直接跟在-p后面）"
    echo "示例: $0 -pMy@Complex#Password123 /home/user /etc /var/log /important/file.txt"
    exit 1
}

# 检测系统类型并安装FTP客户端
install_ftp_client() {
    local ftp_client=""
    
    # 检测系统类型
    if command -v apt-get >/dev/null 2>&1; then
        log "检测到 Debian/Ubuntu 系统"
        ftp_client="ftp"
        apt-get update && apt-get install -y $ftp_client
    elif command -v yum >/dev/null 2>&1; then
        log "检测到 RHEL/CentOS 系统"
        ftp_client="ftp"
        yum install -y $ftp_client
    elif command -v dnf >/dev/null 2>&1; then
        log "检测到 Fedora/RHEL 8+ 系统"
        ftp_client="ftp"
        dnf install -y $ftp_client
    elif command -v apk >/dev/null 2>&1; then
        log "检测到 Alpine 系统"
        ftp_client="lftp"
        apk add --no-cache $ftp_client
    elif command -v zypper >/dev/null 2>&1; then
        log "检测到 openSUSE 系统"
        ftp_client="ftp"
        zypper install -y $ftp_client
    else
        error "无法检测系统类型或不受支持的系统"
    fi
    
    # 验证安装是否成功
    if command -v ftp >/dev/null 2>&1 || command -v lftp >/dev/null 2>&1; then
        log "FTP客户端安装/验证成功"
    else
        error "FTP客户端安装失败"
    fi
}

# 检查FTP客户端是否已安装
check_ftp_client() {
    if command -v ftp >/dev/null 2>&1; then
        FTP_CMD="ftp"
        log "找到 ftp 命令"
    elif command -v lftp >/dev/null 2>&1; then
        FTP_CMD="lftp"
        log "找到 lftp 命令"
    else
        warn "未找到FTP客户端，尝试安装..."
        install_ftp_client
        # 重新检查
        if command -v ftp >/dev/null 2>&1; then
            FTP_CMD="ftp"
        elif command -v lftp >/dev/null 2>&1; then
            FTP_CMD="lftp"
        else
            error "FTP客户端安装后仍然不可用"
        fi
    fi
}

# 解析命令行参数
parse_arguments() {
    local password_provided=0
    
    if [ $# -eq 0 ]; then
        usage
    fi

    # 解析-p参数
    while getopts "p:" opt; do
        case $opt in
            p)
                FTP_PASS="$OPTARG"
                password_provided=1
                ;;
            \?)
                usage
                ;;
        esac
    done
    shift $((OPTIND -1))

    # 检查密码是否提供
    if [ $password_provided -eq 0 ]; then
        error "必须通过 -p参数 提供FTP密码"
    fi

    # 检查是否有备份目标
    if [ $# -eq 0 ]; then
        error "必须指定至少一个目录或文件进行备份"
    fi

    # 存储要备份的路径
    BACKUP_PATHS=("$@")
    
    log "密码参数已接收"
    log "备份目标: ${BACKUP_PATHS[*]}"
}

# 验证备份路径是否存在
validate_paths() {
    local invalid_paths=()
    
    for path in "${BACKUP_PATHS[@]}"; do
        if [ ! -e "$path" ]; then
            warn "路径不存在: $path"
            invalid_paths+=("$path")
        fi
    done
    
    if [ ${#invalid_paths[@]} -eq ${#BACKUP_PATHS[@]} ]; then
        error "所有指定的备份路径都不存在"
    elif [ ${#invalid_paths[@]} -gt 0 ]; then
        warn "以下路径将被忽略: ${invalid_paths[*]}"
        # 移除无效路径
        local valid_paths=()
        for path in "${BACKUP_PATHS[@]}"; do
            if [ -e "$path" ]; then
                valid_paths+=("$path")
            fi
        done
        BACKUP_PATHS=("${valid_paths[@]}")
    fi
}

# 创建备份文件
create_backup() {
    local timestamp=$(date +'%Y%m%d_%H%M%S')
    BACKUP_FILE="${BACKUP_PREFIX}_${timestamp}.tar.gz"
    
    log "开始创建备份文件: $BACKUP_FILE"
    
    # 创建临时目录
    local temp_dir=$(mktemp -d)
    trap 'rm -rf "$temp_dir"' EXIT
    
    # 复制要备份的文件和目录到临时位置，保持相对路径结构
    for path in "${BACKUP_PATHS[@]}"; do
        if [ -e "$path" ]; then
            local parent_dir=$(dirname "$path")
            local base_name=$(basename "$path")
            
            if [ "$parent_dir" = "/" ]; then
                # 处理根目录下的文件/目录
                cp -r "$path" "$temp_dir/root_$base_name"
            else
                # 创建父目录结构并复制
                mkdir -p "$temp_dir/$parent_dir"
                cp -r "$path" "$temp_dir/$parent_dir/"
            fi
        fi
    done
    
    # 创建tar.gz压缩包
    if tar -czf "$BACKUP_FILE" -C "$temp_dir" . 2>/dev/null; then
        log "备份文件创建成功: $BACKUP_FILE ($(du -h "$BACKUP_FILE" | cut -f1))"
    else
        error "创建备份文件失败"
    fi
}

# 使用ftp命令上传
upload_with_ftp() {
    log "使用ftp上传文件..."
    
    # 创建ftp命令脚本
    local ftp_script=$(mktemp)
    cat > "$ftp_script" << EOF
open $FTP_SERVER $FTP_PORT
user $FTP_USER $FTP_PASS
binary
mkdir $REMOTE_PATH
cd $REMOTE_PATH
put $BACKUP_FILE
quit
EOF

    if ftp -n < "$ftp_script" > /tmp/ftp_upload.log 2>&1; then
        log "FTP上传成功"
        rm -f "$ftp_script" "/tmp/ftp_upload.log"
        return 0
    else
        error "FTP上传失败，查看 /tmp/ftp_upload.log 获取详细信息"
    fi
}

# 使用lftp命令上传（Alpine Linux）
upload_with_lftp() {
    log "使用lftp上传文件..."
    
    if lftp -e "set ftp:ssl-allow no; open $FTP_SERVER; user $FTP_USER '$FTP_PASS'; mkdir -p $REMOTE_PATH; cd $REMOTE_PATH; put $BACKUP_FILE; quit" > /tmp/lftp_upload.log 2>&1; then
        log "LFTP上传成功"
        rm -f "/tmp/lftp_upload.log"
        return 0
    else
        error "LFTP上传失败，查看 /tmp/lftp_upload.log 获取详细信息"
    fi
}

# 上传备份文件
upload_backup() {
    log "开始上传备份文件到 $FTP_SERVER:$REMOTE_PATH"
    
    case $FTP_CMD in
        "ftp")
            upload_with_ftp
            ;;
        "lftp")
            upload_with_lftp
            ;;
        *)
            error "不支持的FTP命令: $FTP_CMD"
            ;;
    esac
}

# 清理临时文件
cleanup() {
    if [ -f "$BACKUP_FILE" ]; then
        rm -f "$BACKUP_FILE"
        log "已清理本地备份文件: $BACKUP_FILE"
    fi
}

# 主函数
main() {
    log "FTP备份脚本开始执行"
    
    # 解析参数
    parse_arguments "$@"
    
    # 验证路径
    validate_paths
    
    # 检查FTP客户端
    check_ftp_client
    
    # 创建备份
    create_backup
    
    # 上传备份
    upload_backup
    
    # 清理
    cleanup
    
    log "FTP备份完成!"
}

# 脚本入口点
main "$@"