#!/bin/bash

# 一键网络检测脚本
# 功能：自动安装依赖 + 多方案检测 + 详细报告

set -e

# 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'

# 日志函数
log() {
    echo -e "${BLUE}[$(date '+%H:%M:%S')]${NC} $1"
}

success() {
    echo -e "${GREEN}✓${NC} $1"
}

warning() {
    echo -e "${YELLOW}⚠${NC} $1"
}

error() {
    echo -e "${RED}✗${NC} $1"
}

info() {
    echo -e "${CYAN}ℹ${NC} $1"
}

# 检查系统类型
detect_os() {
    if [ -f /etc/os-release ]; then
        . /etc/os-release
        OS=$ID
    else
        OS=$(uname -s)
    fi
    log "检测到系统: $OS"
}

# 安装依赖工具
install_dependencies() {
    log "检查并安装必要的网络工具..."
    
    local tools=("curl" "wget" "netcat" "telnet" "nmap" "traceroute")
    local to_install=()
    
    # 检查缺失的工具
    for tool in "${tools[@]}"; do
        if ! command -v "$tool" &> /dev/null; then
            to_install+=("$tool")
        fi
    done
    
    if [ ${#to_install[@]} -eq 0 ]; then
        success "所有必要工具已安装"
        return 0
    fi
    
    info "需要安装的工具: ${to_install[*]}"
    
    case $OS in
        ubuntu|debian)
            apt update
            apt install -y "${to_install[@]}"
            ;;
        centos|rhel|fedora)
            if command -v dnf &> /dev/null; then
                dnf install -y "${to_install[@]}"
            else
                yum install -y "${to_install[@]}"
            fi
            ;;
        alpine)
            apk add "${to_install[@]}"
            ;;
        *)
            warning "未知系统，请手动安装以下工具: ${to_install[*]}"
            return 1
            ;;
    esac
    
    success "工具安装完成"
}

# 基础网络检测
basic_network_check() {
    log "执行基础网络检测..."
    
    # 检测DNS
    if nslookup google.com &> /dev/null; then
        success "DNS解析正常"
    else
        error "DNS解析失败"
    fi
    
    # 检测网关
    if ip route show default &> /dev/null; then
        local gateway=$(ip route show default | awk '/default/ {print $3}')
        success "默认网关: $gateway"
        
        # ping网关
        if ping -c 2 -W 1 "$gateway" &> /dev/null; then
            success "网关连通性正常"
        else
            error "网关无法连通"
        fi
    fi
    
    # 检测外网
    if ping -c 2 -W 3 8.8.8.8 &> /dev/null; then
        success "外网连通性正常"
    else
        error "外网无法连通"
    fi
}

# 端口检测函数
check_port() {
    local host=$1
    local port=$2
    local timeout=$3
    
    log "检测 $host:$port ..."
    
    # 方法1: nc
    if command -v nc &> /dev/null; then
        if timeout "$timeout" nc -z -w "$timeout" "$host" "$port" &> /dev/null; then
            success "nc检测: 端口 $port 开放"
            return 0
        fi
    fi
    
    # 方法2: telnet
    if command -v telnet &> /dev/null; then
        if echo "quit" | timeout "$timeout" telnet "$host" "$port" 2>&1 | grep -q "Connected\|Escape character"; then
            success "telnet检测: 端口 $port 开放"
            return 0
        fi
    fi
    
    # 方法3: /dev/tcp
    if timeout "$timeout" bash -c "echo > /dev/tcp/$host/$port" &> /dev/null; then
        success "bash检测: 端口 $port 开放"
        return 0
    fi
    
    # 方法4: nmap
    if command -v nmap &> /dev/null; then
        if nmap -p "$port" "$host" 2>&1 | grep -q "$port/tcp open"; then
            success "nmap检测: 端口 $port 开放"
            return 0
        fi
    fi
    
    error "所有方法检测: 端口 $port 关闭"
    return 1
}

# HTTP服务检测
check_http_service() {
    local host=$1
    local port=$2
    
    log "检测HTTP服务..."
    
    # 尝试HTTP
    if curl -s -I --connect-timeout 5 "http://$host:$port/" &> /dev/null; then
        success "HTTP服务正常 (http://$host:$port)"
        return 0
    fi
    
    # 尝试HTTPS
    if curl -s -I --connect-timeout 5 "https://$host:$port/" &> /dev/null; then
        success "HTTPS服务正常 (https://$host:$port)"
        return 0
    fi
    
    error "HTTP/HTTPS服务无法访问"
    return 1
}

# 路由跟踪
trace_route() {
    local host=$1
    
    log "执行路由跟踪..."
    
    if command -v traceroute &> /dev/null; then
        traceroute -w 1 -q 1 -m 15 "$host" | head -20
    elif command -v tracepath &> /dev/null; then
        tracepath "$host" | head -10
    else
        warning "未找到路由跟踪工具"
    fi
}

# 批量端口扫描
scan_common_ports() {
    local host=$1
    
    log "扫描常用端口..."
    local common_ports=(21 22 23 25 53 80 110 143 443 465 587 993 995 1433 1521 3306 3389 5432 5900 6379 27017)
    
    for port in "${common_ports[@]}"; do
        if timeout 2 bash -c "echo > /dev/tcp/$host/$port" 2>/dev/null; then
            success "端口 $port 开放"
        fi
    done
}

# 显示网络信息
show_network_info() {
    log "系统网络信息:"
    
    echo "=== IP地址 ==="
    ip addr show | grep -E "inet |inet6 " | grep -v "127.0.0.1" || true
    
    echo "=== 路由表 ==="
    ip route show | head -10
    
    echo "=== 监听端口 ==="
    ss -tulpn | head -20
}

# 主函数
main() {
    echo -e "${PURPLE}"
    echo "=========================================="
    echo "          一键网络检测脚本"
    echo "=========================================="
    echo -e "${NC}"
    
    # 参数处理
    local target_host=""
    local target_port=""
    
    if [ $# -ge 1 ]; then
        target_host=$1
    fi
    
    if [ $# -ge 2 ]; then
        target_port=$2
    fi
    
    # 如果没有指定目标，使用交互式输入
    if [ -z "$target_host" ]; then
        info "请输入要检测的目标地址:"
        read -r target_host
    fi
    
    # 系统检测和依赖安装
    detect_os
    install_dependencies
    
    echo
    log "开始网络检测..."
    echo
    
    # 显示本地网络信息
    show_network_info
    echo
    
    # 基础网络检测
    basic_network_check
    echo
    
    # 如果指定了目标主机
    if [ -n "$target_host" ]; then
        # 路由跟踪
        trace_route "$target_host"
        echo
        
        # 批量端口扫描
        scan_common_ports "$target_host"
        echo
        
        # 如果指定了端口
        if [ -n "$target_port" ]; then
            check_port "$target_host" "$target_port" 5
            echo
            check_http_service "$target_host" "$target_port"
            echo
        fi
        
        # 交互式端口检测
        info "是否进行自定义端口检测? (y/n)"
        read -r choice
        if [ "$choice" = "y" ] || [ "$choice" = "Y" ]; then
            while true; do
                info "请输入要检测的端口 (输入 'q' 退出):"
                read -r custom_port
                if [ "$custom_port" = "q" ]; then
                    break
                fi
                if [[ "$custom_port" =~ ^[0-9]+$ ]]; then
                    check_port "$target_host" "$custom_port" 5
                    echo
                else
                    error "端口号必须是数字"
                fi
            done
        fi
    fi
    
    echo
    success "网络检测完成!"
    info "检测报告已生成，请查看上方结果"
}

# 脚本帮助
show_help() {
    echo "用法: $0 [目标地址] [端口]"
    echo
    echo "示例:"
    echo "  $0                          # 交互式检测"
    echo "  $0 google.com               # 检测指定域名"
    echo "  $0 192.168.1.1 80           # 检测指定IP和端口"
    echo "  $0 example.com 443          # 检测HTTPS服务"
    echo
    echo "功能:"
    echo "  - 自动安装网络检测工具"
    echo "  - 基础网络连通性检测"
    echo "  - 端口扫描和服务检测"
    echo "  - 路由跟踪和网络诊断"
}

# 参数处理
case "${1:-}" in
    -h|--help|help)
        show_help
        exit 0
        ;;
    *)
        main "$@"
        ;;
esac