#!/bin/bash

## Windows
# Command to run for PSK ID and PSK with powershell
# PSK ID: (1..16 | %{ '{0:x}' -f (Get-Random -Max 16) }) -join ''
# PSK: (1..64 | %{ '{0:x}' -f (Get-Random -Max 16) }) -join ''


# installs the zabbix agent and configures it

# make sure we are running as sudo
if [ "$EUID" -ne 0 ]; then
  echo "Please run as root"
  exit
fi

# get OS ditro and version
OS=$(hostnamectl | awk '/Operating System/ {print $3}')
VM=$(hostnamectl | awk '/Virtualization/ {print $2}')
if [ ${OS} == 'Ubuntu' ]; then
	OS_VERSION=$(hostnamectl | awk '/Operating System/ {print $4}')
else
	OS_VERSION=$(hostnamectl | awk '/Operating System/ {print $5}')
fi

if [ "${VM}" == "vmware" ] || [ "${VM}" == "kvm" ] ; then
	VM="true"
else
	VM="false"
fi

# zabbix server
ZABBIX_SERVER="10.0.10.16"

if [ ${OS} == 'Debian' ]; then
	# Install the repository configuration package. This package contains apt (software package manager) configuration files.
    if [[ ${OS_VERSION} =~ ^9.* ]]; then
    	wget -P /tmp/ https://repo.zabbix.com/zabbix/6.0/debian/pool/main/z/zabbix-release/zabbix-release_6.0-4+debian9_all.deb
        dpkg -i /tmp/zabbix-release_6.0-4+debian9_all.deb
    fi
	if [[ ${OS_VERSION} =~ ^10.* ]]; then
    	wget -P /tmp/ https://repo.zabbix.com/zabbix/6.0/debian/pool/main/z/zabbix-release/zabbix-release_6.0-4+debian10_all.deb
        dpkg -i /tmp/zabbix-release_6.0-4+debian10_all.deb
    fi
    if [[ ${OS_VERSION} =~ ^11.* ]]; then
    	wget -P /tmp/ https://repo.zabbix.com/zabbix/6.0/debian/pool/main/z/zabbix-release/zabbix-release_6.0-4+debian11_all.deb
        dpkg -i /tmp/zabbix-release_6.0-4+debian11_all.deb
    fi
    if [[ ${OS_VERSION} =~ ^12.* ]]; then
    	wget -P /tmp/ https://repo.zabbix.com/zabbix/6.0/debian/pool/main/z/zabbix-release/zabbix-release_6.0-5+debian12_all.deb
        dpkg -i /tmp/zabbix-release_6.0-5+debian12_all.deb
    fi
    # create missing directory
    mkdir /etc/zabbix/zabbix_agentd.conf.d
    # update the cache
    apt update
    # install the agent
    apt install -y zabbix-agent
    # make a dir
    mkdir /etc/zabbix/zabbix_agentd.d

    
elif [ ${OS} == 'Ubuntu' ]; then
	# Install the repository configuration package. This package contains apt (software package manager) configuration files.
    if [[ ${OS_VERSION} =~ 20.04 ]]; then
    	wget -P /tmp/ https://repo.zabbix.com/zabbix/6.0/ubuntu/pool/main/z/zabbix-release/zabbix-release_6.0-4+ubuntu20.04_all.deb
        dpkg -i /tmp/zabbix-release_6.0-4+ubuntu20.04_all.deb
    fi
    if [[ ${OS_VERSION} =~ 22.04 ]]; then
    	wget -P /tmp/ https://repo.zabbix.com/zabbix/6.0/ubuntu/pool/main/z/zabbix-release/zabbix-release_6.0-4+ubuntu22.04_all.deb
        dpkg -i /tmp/zabbix-release_6.0-4+ubuntu22.04_all.deb
    fi
    # update the cache
    apt update
    # install the agent
    apt install -y zabbix-agent
    
elif [ ${OS} == 'CentOS' ] || [ "${OS}" == "Rocky" ]; then
    # Install the repository configuration package. This package contains yum (software package manager) configuration files.
   	if [ ${OS_VERSION} == 7 ]; then 
   		rpm -Uvh https://repo.zabbix.com/zabbix/6.0/rhel/7/x86_64/zabbix-release-6.0-4.el7.noarch.rpm
        yum clean all
        yum install -y zabbix-agent
    fi
    if [ ${OS_VERSION} == 8 ]; then 
   		rpm -Uvh https://repo.zabbix.com/zabbix/6.0/rhel/8/x86_64/zabbix-release-6.0-4.el8.noarch.rpm
        dnf clean all
        dnf install -y zabbix-agent
    fi 
    if [ "${OS_VERSION}" == "9.0" ]; then 
        # zabbix is also supplied via the EPEL Repo, we need to exlude it from there
        if [ $(grep -c "^excludepkgs=" /etc/yum.repos.d/epel.repo) -eq 1 ]; then
            sed --in-place '/^excludepkgs=/ s/$/ zabbix*/' /etc/yum.repos.d/epel.repo
        else
            sed --in-place '/^enabled=1/ s/$/\nexcludepkgs=zabbix*/' /etc/yum.repos.d/epel.repo
        fi
   		rpm -Uvh https://repo.zabbix.com/zabbix/6.0/rhel/9/x86_64/zabbix-release-6.0-4.el9.noarch.rpm
        dnf clean all
        dnf install -y zabbix-agent
    fi 
    cat << EOF >> /etc/firewalld/services/zabbix-agent.xml
<?xml version="1.0" encoding="utf-8"?>
    <service>
        <short>zabbix agent</short>
        <description>zabbix agent</description>
        <port protocol="tcp" port="10050"/>
    </service>
EOF
    sleep 5
    firewall-cmd --add-service=zabbix-agent --permanent
    firewall-cmd --reload
    
else
    echo "You are running an unsupported OS"
    echo "Support OSes: Debian 9/10/11, Ubuntu 20.04/22.04, CentOS 7/8, Rocky 9 with EPEL"
    echo "Your OS: ${OS} ${OS_VERSION}"
    exit
fi

# test if not a VM and if so, install the smartctl stuff
if [ "${VM}" == "false" ]; then
    # download the sudo file
    wget -O /etc/sudoers.d/sudoers_zabbix_smartctl https://raw.githubusercontent.com/v-zhuravlev/zbx-smartctl/master/sudoers_zabbix_smartctl
    chmod 440 /etc/sudoers.d/sudoers_zabbix_smartctl
    # make the directories
    mkdir /etc/zabbix/zabbix_agentd.d /etc/zabbix/scripts
    # download the conf and discovery scripts
    wget -O /etc/zabbix/zabbix_agentd.d/zabbix_smartctl.conf https://raw.githubusercontent.com/v-zhuravlev/zbx-smartctl/master/zabbix_smartctl.conf
    wget -O /etc/zabbix/scripts/smartctl-disks-discovery.pl https://raw.githubusercontent.com/v-zhuravlev/zbx-smartctl/master/discovery-scripts/nix/smartctl-disks-discovery.pl
    chown zabbix:zabbix /etc/zabbix/scripts/smartctl-disks-discovery.pl
    chmod u+x /etc/zabbix/scripts/smartctl-disks-discovery.pl
fi


#cheeck before running this as it adds lines to keep comments
if [ $(grep -c "^Server=127.0.0.1" /etc/zabbix/zabbix_agentd.conf) -eq 1 ]; then
    # ask for the hostname
    read -e -p "Enter Hostname: " -i "$(cat /etc/hostname)" hostname

    # set the include to add the smartctl config directory
    # sed --in-place $'s/^# Hostname=/# Hostname=\\\nHostname='${hostname}'/' /etc/zabbix/zabbix_agentd.conf
    sed --in-place $'s/^Include=\/etc\/zabbix\/zabbix_agentd.conf.d\/\*.conf/Include=\/etc\/zabbix\/zabbix_agentd.conf.d\/\*.conf\\\nInclude=\/etc\/zabbix\/zabbix_agentd.d\/\*.conf/' /etc/zabbix/zabbix_agentd.conf

    # configure the hostname, check for older config and newer config
    if [ $(grep -c "^Hostname=Zabbix" /etc/zabbix/zabbix_agentd.conf) -eq 1 ]; then 
        sed --in-place 's/^Hostname=Zabbix\ server/Hostname='${hostname}'/' /etc/zabbix/zabbix_agentd.conf
    else
        sed --in-place $'s/^# Hostname=/# Hostname=\\\nHostname='${hostname}'/' /etc/zabbix/zabbix_agentd.conf
    fi
    # configure the zabbix server
    sed --in-place 's/^Server=127.0.0.1/Server='"${ZABBIX_SERVER}"'/' /etc/zabbix/zabbix_agentd.conf
    # configure the zabbix server
    sed --in-place 's/^ServerActive=127.0.0.1/ServerActive='"${ZABBIX_SERVER}"'/' /etc/zabbix/zabbix_agentd.conf
    # configure the encryption
    sed --in-place $'s/^# TLSAccept=unencrypted/# TLSAccept=unencrypted\\\nTLSAccept=psk/' /etc/zabbix/zabbix_agentd.conf
    sed --in-place $'s/^# TLSConnect=unencrypted/# TLSConnect=unencrypted\\\nTLSConnect=psk/' /etc/zabbix/zabbix_agentd.conf
    # generate random PSK ID
    PSKID=$(openssl rand -hex 8)
    sed --in-place $'s/^# TLSPSKIdentity=/# TLSPSKIdentity=\\\nTLSPSKIdentity='${PSKID}'/' /etc/zabbix/zabbix_agentd.conf
    # generate psk
    TLSPSK=$(openssl rand -hex 32 | tee /etc/zabbix/zabbix_agentd.psk)
    sed --in-place $'s/^# TLSPSKFile=/# TLSPSKFile=\\\nTLSPSKFile=\/etc\/zabbix\/zabbix_agentd.psk/' /etc/zabbix/zabbix_agentd.conf

    echo "############################################################"
    echo "##                 Encryption Details                     ##"
    echo "## Please enter the PSK ID and PSK into the Zabbix Server ##"
    echo "############################################################"
    echo "PSK Identity = ${PSKID}"
    echo "PSK = ${TLSPSK}"

fi

systemctl restart zabbix-agent 

systemctl enable zabbix-agent