#!/bin/bash
# Description: install Shadowsocks Server
# Author: tlanyan<https://tlanyan.me>

function checkSystem()
{
    result=$(id | awk '{print $1}')
    if [ $result != "uid=0(root)" ]; then
        echo "请以root身份执行该脚本！"
        exit 1
    fi

    if [ ! -f /etc/centos-release ];then
        echo false
        return
    fi
    
    result=`cat /etc/centos-release|grep "CentOS Linux release 7"`
    if [ "$result" = "" ]; then
        echo false
    fi
    echo true
}

function installSS()
{
    yum install -y epel-release
    wget -O /etc/yum.repos.d/librehat-shadowsocks-epel-7.repo 'https://copr.fedorainfracloud.org/coprs/librehat/shadowsocks/repo/epel-7/librehat-shadowsocks-epel-7.repo'
    yum install -y shadowsocks-libev nginx
    systemctl status firewalld > /dev/null 2>&1
    if [ $? -eq 0 ];then
        firewall-cmd --permanent --add-port=${port}/tcp
        firewall-cmd --permanent --add-port=${port}/udp
        firewall-cmd --permanent --add-service=http
        firewall-cmd --reload
    fi
    if [ -s /etc/selinux/config ] && grep 'SELINUX=enforcing' /etc/selinux/config; then
        sed -i 's/SELINUX=enforcing/SELINUX=permissive/g' /etc/selinux/config >> /dev/null 2>&1
        setenforce 0
    fi
    systemctl enable shadowsocks-libev nginx
    systemctl start shadowsocks-libev nginx
}

function installBBR()
{
    result=$(lsmod | grep bbr)
    if [ "$result" != "" ]; then
        echo BBR模块已安装!
        return;
    fi

    echo 安装BBR...
    rpm --import https://www.elrepo.org/RPM-GPG-KEY-elrepo.org
    rpm -Uvh http://www.elrepo.org/elrepo-release-7.0-4.el7.elrepo.noarch.rpm
    yum --enablerepo=elrepo-kernel install kernel-ml -y
    yum remove kernel-3.* -y
    grub2-set-default 0
    echo "tcp_bbr" >> /etc/modules-load.d/modules.conf
    echo "net.core.default_qdisc=fq" >> /etc/sysctl.conf
    echo "net.ipv4.tcp_congestion_control=bbr" >> /etc/sysctl.conf
}

function showTip()
{
    echo ============================================
    echo "              安装成功！                  "
    echo ""
    echo " SS配置文件：/etc/shadowsocks-libev/config.json，请按照自己需要进行修改"
    echo ""
    echo " systemctl start shadowsocks-libev启动程序,systemctl stop shadowsocks-libev停止程序"
    echo   
    echo " 如果连接不成功，请注意查看安全组/防火墙是否已放行端口"
    echo  
    echo " 为使BBR模块生效，系统将在30秒后重启"
    echo ============================================

    sleep 30

    reboot
}

result=$(checkSystem)
if [ "$result" != "true" ]; then
    echo "本脚本仅在CentOS 7系统上测试过!"
    exit 1
fi

echo -n "系统版本:  "
cat /etc/centos-release

installBBR

installSS

showTip