#!/bin/bash

# ============================================
# 远程挂载管理脚本
# 功能：挂载远程CIFS/NFS共享到本地目录
# 支持挂载共享的任意子目录
# ============================================

# 配置部分
readonly SCRIPT_NAME="$(basename "${BASH_SOURCE[0]}")"
readonly SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
readonly REMOTE_IP="192.168.187.109"
readonly BASE_DIR="$HOME/workspace"
readonly CREDENTIALS="Administrator%tomypyxh"

# 颜色定义
readonly COLOR_CYAN="\033[1;36m"
readonly COLOR_RESET="\033[0m"

# ============================================
# 函数定义
# ============================================

show_help() {
    echo -e "${COLOR_CYAN}用法:${COLOR_RESET}"
    echo -e "${COLOR_CYAN}  $SCRIPT_NAME <-cifs|-nfs>${COLOR_RESET}"
    echo -e "${COLOR_CYAN}  $SCRIPT_NAME <-cifs|-nfs> sharename${COLOR_RESET}"
    echo -e "${COLOR_CYAN}  $SCRIPT_NAME <-cifs|-nfs> sharename[/子目录]${COLOR_RESET}"
    echo -e "${COLOR_CYAN}  $SCRIPT_NAME <-cifs|-nfs> sharename[/子目录] 本地目录${COLOR_RESET}"
    echo
    
    # 暂不处理未指定协议
    #echo -e "${COLOR_CYAN}  $SCRIPT_NAME sharename${COLOR_RESET}"
    #echo -e "${COLOR_CYAN}  $SCRIPT_NAME sharename[/子目录]${COLOR_RESET}"
    #echo -e "${COLOR_CYAN}  $SCRIPT_NAME sharename[/子目录] 本地目录${COLOR_RESET}"
    #echo
    
    echo "参数说明:"
    echo "  -cifs: 使用CIFS协议挂载Windows共享"
    echo "  -nfs:  使用NFS协议挂载Linux共享"
    echo "  sharename: 远程共享名称"
    echo "  [/子目录]: 可选，要挂载的共享子目录路径"
    echo "  本地目录: 可选，本地挂载点路径"
    echo
    echo "示例:"
    echo "  $SCRIPT_NAME -cifs sharename"
    echo "  $SCRIPT_NAME -cifs sharename/subdir"
    echo "  $SCRIPT_NAME -cifs sharename/subdir/deeper"
    echo "  $SCRIPT_NAME -cifs sharename/subdir ~/myproject"
    #echo "  $SCRIPT_NAME myshare/subdir"
}

# 检查命令是否存在
check_command() {
    if ! command -v "$1" >/dev/null 2>&1; then
        echo "错误: 找不到命令 '$1'，请先安装"
        exit 1
    fi
}

# 检查是否已挂载
is_already_mounted() {
    local remote_path="$1"
    local local_dir="$2"
    
    # 使用mapfile读取挂载信息
    mapfile -t mount_info < <(sudo mount 2>/dev/null)
    
    for line in "${mount_info[@]}"; do
        if [[ "$line" == *"$remote_path"* && "$line" == *"$local_dir"* ]]; then
            return 0
        fi
    done
    return 1
}

# 获取远程共享列表
get_remote_shares() {
    local protocol="$1"
    
    case "$protocol" in
        cifs)
            check_command "smbclient"
            # 匹配以可选空白开头，后跟一个标识符（单词），再跟一个或多个空白，最后是 "Disk" 的行
            # 获取共享列表，过滤掉系统共享(以$结尾的),删除所有空行
            #sudo smbclient -U "$CREDENTIALS" -L "$REMOTE_IP" 2>/dev/null | \
            #    grep -E '^[[:space:]]*[A-Za-z0-9_]+[[:space:]]+Disk' | \
            #    awk '{print $1}' | sed '/\$$/d' | grep -v '^$'
            
            # 获取共享列表，保留系统共享(以$结尾的),删除所有空行
            #sudo smbclient -U "$CREDENTIALS" -L "$REMOTE_IP" 2>/dev/null | \
            #    grep -E '^[[:space:]]*[A-Za-z0-9_\$]+[[:space:]]+Disk' | \
            #    awk '{print $1}' | sed '/\$$/d' | grep -v '^$'
            
            # 保留 C$、D$等    
            sudo smbclient -U "$CREDENTIALS" -L "$REMOTE_IP" 2>/dev/null | \
                grep -E '^[[:space:]]*[A-Za-z0-9_\$]+[[:space:]]+Disk' | \
                awk '{print $1}' | grep -v '^$'
            ;;
        nfs)
            check_command "showmount"
            sudo showmount -e "$REMOTE_IP" 2>/dev/null | \
                sed "1d" | awk '{print $1}' | cut -d'/' -f2
            ;;
        *)
            echo "未知协议: $protocol"
            return 1
            ;;
    esac
}

# 验证共享是否存在（只验证共享根目录）
validate_share() {
    local protocol="$1"
    local share_name="$2"
    
    # 提取共享根目录名称（第一个/之前的部分）
    local base_share="${share_name%%/*}"
    
    local shares
    mapfile -t shares < <(get_remote_shares "$protocol")
    
    for share in "${shares[@]}"; do
        if [[ "$share" == "$base_share" ]]; then
            return 0
        fi
    done
    
    return 1
}

# 解析共享名和子目录
parse_share_with_subdir() {
    local input="$1"
    local -n ref_share_name="$2"
    local -n ref_subdir_path="$3"
    
    # 如果包含子目录路径
    if [[ "$input" == */* ]]; then
        ref_share_name="${input%%/*}" # 从末尾开始匹配，删除最长匹配的部分
        ref_subdir_path="${input#*/}" # 从开头开始匹配，删除最短匹配的部分
        
        # 确保共享名不为空
        if [[ -z "$ref_share_name" ]]; then
            echo "错误: 共享名不能为空"
            return 1
        fi
    else
        ref_share_name="$input"
        ref_subdir_path=""
    fi
    
    return 0
}

# 确定本地目录
get_local_dir() {
    local share_name="$1"
    local subdir_path="$2"
    local user_arg="$3"
    
    if [[ -n "$user_arg" ]]; then
        # 用户指定了本地目录
        if [[ "${user_arg:0:1}" == "/" ]]; then
            # 绝对路径
            echo "$user_arg"
        else
            # 相对路径，基于 BASE_DIR
            echo "$BASE_DIR/$user_arg"
        fi
    elif [[ -n "$subdir_path" ]]; then
        # 如果有子目录，使用共享名+子目录名作为本地目录名，避免使用斜杠创建多层目录
        # local safe_subdir="${subdir_path//\//_}"
        # echo "$BASE_DIR/${share_name}_${safe_subdir}"
        
        # 如果有子目录，取最后一个子目录
        local array=(${subdir_path//\// })
        local alen=${#array[@]}
        local pos=$(( pos = alen - 1 ))
        local tailv=${array[$pos]}
        echo "$BASE_DIR/${tailv}"
    else
        # 默认路径
        echo "$BASE_DIR/$share_name"
    fi
}

# 构建远程路径
get_remote_path() {
    local protocol="$1"
    local share_name="$2"
    local subdir_path="$3"
    
    local remote_path=""
    
    if [[ "$protocol" == "cifs" ]]; then
        remote_path="//$REMOTE_IP/$share_name"
        if [[ -n "$subdir_path" ]]; then
            remote_path="$remote_path/$subdir_path"
        fi
    else
        remote_path="$REMOTE_IP:/$share_name"
        if [[ -n "$subdir_path" ]]; then
            remote_path="$remote_path/$subdir_path"
        fi
    fi
    
    echo "$remote_path"
}

# 获取挂载选项
get_mount_options() {
    local protocol="$1"
    
    case "$protocol" in
        cifs)
            # 获取当前用户的uid和gid
            local uid=$(id -u)
            local gid=$(id -g)
            
            local array=(${CREDENTIALS/\%/ })
            local susername=${array[0]}
            local spassword=${array[1]}
            
            # CIFS挂载选项
            local opt
            opt="username=$susername,password=$spassword"
            opt="$opt,vers=2.0,dir_mode=0755,file_mode=0666,uid=$uid,gid=$gid,nounix,noserverino"
            echo "$opt"
            
            ;;
        nfs)
            # NFS挂载选项
            echo "rw,bg,retry=1"
            ;;
        *)
            echo ""
            ;;
    esac
}

# 执行挂载
mount_share() {
    local protocol="$1"
    local remote_dir="$2"
    local local_dir="$3"
    
    # 检查本地目录是否存在
    if [[ ! -d "$local_dir" ]]; then
        #echo "创建目录: $local_dir"    
        mkdir -p "$local_dir" || {
            echo "错误: 无法创建目录 $local_dir"
            return 1
        }
    fi
    
    # 获取挂载选项
    local options="$(get_mount_options "$protocol")"
    
    # 执行挂载
    #echo "正在挂载: $remote_dir -> $local_dir"
    #echo "挂载选项: $options"
    
    if sudo mount -t "$protocol" -o "$options" "$remote_dir" "$local_dir"; then
        #echo "挂载成功"
        echo "挂载成功: $remote_dir -> $local_dir"
        return 0
    else
        #echo "错误: 挂载失败"
        #echo "提示: 确保远程路径 $remote_dir 存在且可访问"
        echo "挂载失败: $remote_dir -> $local_dir"
        return 1
    fi
}

# ============================================
# 主程序
# ============================================

main() {
    # 参数检查
    if [[ "$#" -eq 0 || "$1" == "-h" || "$1" == "--help" ]]; then
        show_help
        exit 0
    fi
    
    # 变量初始化
    local protocol=""
    local share_name=""
    local subdir_path=""
    local local_dir=""
    local remote_dir=""
    
    #echo "pwd  : $(pwd)"
    
    # 处理 -cifs/-nfs 参数
    if [[ "$1" == "-cifs" || "$1" == "-nfs" ]]; then
        protocol="${1#-}"  # 去掉开头的'-'
        
        # 参数个数检查
        if [[ "$#" -gt 3 ]]; then
            echo "错误: 参数过多"
            show_help
            exit 1
        fi
        
        if [[ "$#" -eq 1 ]]; then
            # 仅列出共享
            echo -e "${COLOR_CYAN}可用的${protocol}共享:${COLOR_RESET}"
            # read -r中的-r选项的作用：原始读取，禁止反斜杠转义
            get_remote_shares "$protocol" | while read -r share; do
                echo "  $share"
            done
            #echo
            #echo "提示: 要挂载共享的子目录，使用: $SCRIPT_NAME -$protocol 共享名/子目录路径"
            exit 0
        fi
        
        # 解析共享名和子目录路径
        if ! parse_share_with_subdir "$2" share_name subdir_path; then
            exit 1
        fi
        
        # 验证共享根目录是否存在
        if ! validate_share "$protocol" "$share_name"; then
            echo "错误: ${protocol}共享 '$share_name' 不存在"
            echo "可用的共享有:"
            get_remote_shares "$protocol" | while read -r share; do
                echo "  $share"
            done
            exit 1
        fi
	
        # 确定本地目录
        # ${3:-}: 如果第3个参数未设置或为空，则替换为空字符串
        local_dir=$(get_local_dir "$share_name" "$subdir_path" "${3:-}")
        
        # 构建远程路径
        remote_dir=$(get_remote_path "$protocol" "$share_name" "$subdir_path")
        
    else
        # 自动检测模式
        if [[ "$#" -gt 2 ]]; then
            echo "错误: 参数过多"
            show_help
            exit 1
        fi
        
        # 解析共享名和子目录路径
        if ! parse_share_with_subdir "$1" share_name subdir_path; then
            exit 1
        fi
        
        # 确定本地目录
        local_dir="$(get_local_dir "$share_name" "$subdir_path" "${2:-}")"
        
        # 检测共享类型
        local found_cifs=false
        local found_nfs=false
        
        if validate_share "cifs" "$share_name"; then
            found_cifs=true
        fi
        
        if validate_share "nfs" "$share_name"; then
            found_nfs=true
        fi
        
        if [[ "$found_cifs" == false && "$found_nfs" == false ]]; then
            echo "错误: 未找到共享 '$share_name'"
            exit 1
        elif [[ "$found_cifs" == true && "$found_nfs" == true ]]; then
            echo "错误: 共享 '$share_name' 同时存在于CIFS和NFS中, 请明确指定协议"
            exit 1
        fi
        
        # 确定协议和远程路径
        if [[ "$found_cifs" == true ]]; then
            protocol="cifs"
        else
            protocol="nfs"
        fi
        
        # 构建远程路径
        remote_dir=$(get_remote_path "$protocol" "$share_name" "$subdir_path")
    fi
    
    # 检查是否已挂载
    if is_already_mounted "$remote_dir" "$local_dir"; then
        echo "信息: 共享已挂载到 $local_dir"
        exit 0
    fi
    
    # 显示挂载信息
    #echo "挂载信息:"
    #echo "  协议: $protocol"
    #echo "  共享: $share_name"
    #[[ -n "$subdir_path" ]] && echo "  子目录: $subdir_path"
    #echo "  远程路径: $remote_dir"
    #echo "  本地目录: $local_dir"
    #echo
    #exit 0
    
    # 执行挂载
    mount_share "$protocol" "$remote_dir" "$local_dir"
}

# 异常处理
trap 'echo "脚本被中断"; exit 1' INT TERM

# 运行主程序
main "$@"