#!/bin/bash

# 颜色定义
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
BLUE='\033[0;34m'
PURPLE='\033[0;35m'
CYAN='\033[0;36m'
NC='\033[0m' # No Color

# 显示标题
echo -e "${CYAN}"
echo "================================================"
echo "           网络连接诊断工具 v2.0"
echo "================================================"
echo -e "${NC}"

# 函数：显示帮助信息
show_help() {
    echo -e "${YELLOW}使用说明：${NC}"
    echo "1. 本工具用于测试网络连接和端口状态"
    echo "2. 支持IP地址和域名测试"
    echo "3. 可以测试多个端口"
    echo "4. 包含详细的连接状态分析"
    echo ""
}

# 函数：输入IP/域名
input_target() {
    while true; do
        echo -e "${BLUE}请输入要测试的目标IP地址或域名：${NC}"
        read -p "目标地址: " TARGET
        
        if [ -z "$TARGET" ]; then
            echo -e "${RED}错误：目标地址不能为空！${NC}"
            continue
        fi
        
        # 简单验证格式
        if [[ "$TARGET" =~ ^[0-9]+\.[0-9]+\.[0-9]+\.[0-9]+$ ]] || [[ "$TARGET" =~ ^[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}$ ]]; then
            break
        else
            echo -e "${RED}错误：请输入有效的IP地址或域名！${NC}"
        fi
    done
}

# 函数：输入端口
input_ports() {
    echo -e "${BLUE}请输入要测试的端口（多个端口用空格分隔）：${NC}"
    read -p "端口: " PORTS_INPUT
    
    if [ -z "$PORTS_INPUT" ]; then
        echo -e "${YELLOW}警告：未输入端口，使用默认端口 25555${NC}"
        PORTS=("25555")
    else
        # 将输入的端口转换为数组
        PORTS=($PORTS_INPUT)
    fi
}

# 函数：Ping测试
ping_test() {
    echo -e "\n${PURPLE}=== Ping 连通性测试 ===${NC}"
    echo -e "目标: ${YELLOW}$TARGET${NC}"
    
    if ping -c 4 -W 2 "$TARGET" &> /dev/null; then
        echo -e "${GREEN}✓ Ping 测试成功 - 网络连通正常${NC}"
        PING_RESULT=$(ping -c 4 -W 2 "$TARGET" | grep -E "packets transmitted|min/avg/max")
        echo "$PING_RESULT"
    else
        echo -e "${RED}✗ Ping 测试失败 - 网络不通${NC}"
        return 1
    fi
}

# 函数：端口扫描测试
port_scan_test() {
    local port=$1
    echo -e "\n${PURPLE}=== 端口 $port 测试 ===${NC}"
    
    # 测试1: nc 命令
    echo -e "${CYAN}[测试1] NC 端口扫描...${NC}"
    if command -v nc &> /dev/null; then
        if nc -zv -w 3 "$TARGET" "$port" &> /dev/null; then
            echo -e "${GREEN}✓ NC 测试 - 端口 $port 开放${NC}"
        else
            echo -e "${RED}✗ NC 测试 - 端口 $port 关闭或无法连接${NC}"
        fi
    else
        echo -e "${YELLOW}⚠ NC 命令未安装，跳过此测试${NC}"
    fi
    
    # 测试2: TCP 连接测试
    echo -e "${CYAN}[测试2] TCP 连接测试...${NC}"
    if timeout 3 bash -c "echo > /dev/tcp/$TARGET/$port" 2>/dev/null; then
        echo -e "${GREEN}✓ TCP 测试 - 端口 $port 可连接${NC}"
    else
        echo -e "${RED}✗ TCP 测试 - 端口 $port 无法连接${NC}"
    fi
    
    # 测试3: telnet 测试（如果可用）
    echo -e "${CYAN}[测试3] Telnet 测试...${NC}"
    if command -v telnet &> /dev/null; then
        if timeout 3 telnet "$TARGET" "$port" 2>&1 | grep -q "Connected"; then
            echo -e "${GREEN}✓ Telnet 测试 - 端口 $port 可连接${NC}"
        else
            echo -e "${RED}✗ Telnet 测试 - 端口 $port 无法连接${NC}"
        fi
    else
        echo -e "${YELLOW}⚠ Telnet 命令未安装，跳过此测试${NC}"
    fi
}

# 函数：DNS解析测试
dns_test() {
    echo -e "\n${PURPLE}=== DNS 解析测试 ===${NC}"
    if [[ "$TARGET" =~ ^[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}$ ]]; then
        echo -e "${CYAN}检测到域名，进行DNS解析...${NC}"
        if nslookup "$TARGET" &> /dev/null; then
            echo -e "${GREEN}✓ DNS 解析成功${NC}"
            nslookup "$TARGET" | grep -A 10 "Name:"
        else
            echo -e "${RED}✗ DNS 解析失败${NC}"
        fi
    else
        echo -e "${CYAN}检测到IP地址，跳过DNS解析测试${NC}"
    fi
}

# 函数：路由跟踪
trace_route() {
    echo -e "\n${PURPLE}=== 路由跟踪测试 ===${NC}"
    echo -e "${YELLOW}是否进行路由跟踪？(y/n, 可能需要较长时间)${NC}"
    read -p "选择: " DO_TRACE
    
    if [[ "$DO_TRACE" == "y" || "$DO_TRACE" == "Y" ]]; then
        if command -v traceroute &> /dev/null; then
            echo -e "${CYAN}开始路由跟踪...${NC}"
            traceroute -m 15 "$TARGET"
        elif command -v tracepath &> /dev/null; then
            echo -e "${CYAN}开始路由跟踪 (使用 tracepath)...${NC}"
            tracepath "$TARGET"
        else
            echo -e "${YELLOW}⚠ 路由跟踪命令未安装${NC}"
        fi
    fi
}

# 函数：生成测试报告
generate_report() {
    echo -e "\n${PURPLE}=== 测试报告 ===${NC}"
    echo -e "测试时间: $(date)"
    echo -e "目标地址: ${YELLOW}$TARGET${NC}"
    echo -e "测试端口: ${YELLOW}${PORTS[*]}${NC}"
    
    # 汇总结果
    echo -e "\n${CYAN}汇总结果:${NC}"
    if ping -c 1 -W 2 "$TARGET" &> /dev/null; then
        echo -e "${GREEN}● 网络连通性: 正常${NC}"
    else
        echo -e "${RED}● 网络连通性: 异常${NC}"
    fi
    
    echo -e "● 端口状态:"
    for port in "${PORTS[@]}"; do
        if timeout 2 bash -c "echo > /dev/tcp/$TARGET/$port" 2>/dev/null; then
            echo -e "  端口 $port: ${GREEN}开放${NC}"
        else
            echo -e "  端口 $port: ${RED}关闭${NC}"
        fi
    done
}

# 主函数
main() {
    # 显示帮助信息
    show_help
    
    # 获取用户输入
    input_target
    input_ports
    
    echo -e "\n${GREEN}开始网络诊断测试...${NC}"
    echo -e "目标: ${YELLOW}$TARGET${NC}"
    echo -e "端口: ${YELLOW}${PORTS[*]}${NC}"
    echo ""
    
    # 执行各项测试
    dns_test
    ping_test
    ping_result=$?
    
    # 如果ping不通，询问是否继续
    if [ $ping_result -ne 0 ]; then
        echo -e "\n${YELLOW}警告: Ping 测试失败，目标可能无法访问${NC}"
        echo -e "${YELLOW}是否继续端口测试？(y/n)${NC}"
        read -p "选择: " CONTINUE
        if [[ "$CONTINUE" != "y" && "$CONTINUE" != "Y" ]]; then
            echo -e "${RED}测试终止${NC}"
            exit 1
        fi
    fi
    
    # 端口测试
    for port in "${PORTS[@]}"; do
        port_scan_test "$port"
    done
    
    # 路由跟踪
    trace_route
    
    # 生成报告
    generate_report
    
    echo -e "\n${GREEN}网络诊断完成！${NC}"
}

# 检查必要命令
check_requirements() {
    local missing=()
    
    for cmd in ping nc timeout; do
        if ! command -v "$cmd" &> /dev/null; then
            missing+=("$cmd")
        fi
    done
    
    if [ ${#missing[@]} -gt 0 ]; then
        echo -e "${RED}错误: 缺少必要的命令: ${missing[*]}${NC}"
        echo -e "${YELLOW}请安装缺少的命令后重新运行脚本${NC}"
        exit 1
    fi
}

# 脚本入口
if [ "$1" = "-h" ] || [ "$1" = "--help" ]; then
    show_help
    exit 0
fi

# 检查系统要求
check_requirements

# 运行主程序
main