#!/bin/sh
#
# NGINX Amplify Agent install script
#
# Copyright (C) Nginx, Inc.
#

packages_url="https://packages.amplify.nginx.com"
package_name="nginx-amplify-agent"
public_key_url="https://nginx.org/keys/nginx_signing.key"
agent_conf_path="/etc/amplify-agent"
agent_conf_file="${agent_conf_path}/agent.conf"
amplify_hostname=""
api_url="https://receiver.amplify.nginx.com:443"
api_ping_url="${api_url}/ping/"
api_receiver_url="${api_url}/1.4"
nginx_conf_file="/etc/nginx/nginx.conf"
amplify_pid_file="/var/run/amplify-agent/amplify-agent.pid"
store_uuid="False"
python_supported=2

#
# Functions
#

# Get OS information
get_os_name () {

    centos_flavor="centos"

    # Use lsb_release if possible
    if command -V lsb_release > /dev/null 2>&1; then
        os=`lsb_release -is | tr '[:upper:]' '[:lower:]'`
        codename=`lsb_release -cs | tr '[:upper:]' '[:lower:]'`
        release=`lsb_release -rs | sed 's/\..*$//'`

        case "$os" in
            redhatenterprise|redhatenterpriseserver|oracleserver)
                os="rhel"
                centos_flavor="red hat linux"
                ;;
        esac
    # Otherwise it's getting a little bit more tricky
    else
        if ! ls /etc/*-release > /dev/null 2>&1; then
            os=`uname -s | \
                tr '[:upper:]' '[:lower:]'`
        elif cat /etc/*-release | grep '^ID="almalinux"' > /dev/null 2>&1; then
            os="centos"
            centos_flavor="almalinux"
        elif cat /etc/*-release | grep '^ID="rocky"' > /dev/null 2>&1; then
            os="centos"
            centos_flavor="rocky"
        else
            os=`cat /etc/*-release | grep '^ID=' | \
                sed 's/^ID=["]*\([a-zA-Z]*\).*$/\1/' | \
                tr '[:upper:]' '[:lower:]'`

            if [ -z "$os" ]; then
                if grep -i "oracle linux" /etc/*-release > /dev/null 2>&1 || \
                   grep -i "red hat" /etc/*-release > /dev/null 2>&1; then
                    os="rhel"
                else
                    if grep -i "centos" /etc/*-release > /dev/null 2>&1; then
                        os="centos"
                    else
                        os="linux"
                    fi
                fi
            fi
        fi

        case "$os" in
            ubuntu)
                codename=`cat /etc/*-release | grep '^DISTRIB_CODENAME' | \
                          sed 's/^[^=]*=\([^=]*\)/\1/' | \
                          tr '[:upper:]' '[:lower:]'`
                ;;
            debian)
                codename=`cat /etc/*-release | grep '^VERSION=' | \
                          sed 's/.*(\(.*\)).*/\1/' | \
                          tr '[:upper:]' '[:lower:]'`
                ;;
            centos)
                codename=`cat /etc/*-release | grep -i 'almalinux\|rocky\|centos.*(' | \
                          sed 's/.*(\(.*\)).*/\1/' | head -1 | \
                          tr '[:upper:]' '[:lower:]'`
                # For CentOS grab release
                release=`cat /etc/*-release | grep -i '^version_id=' | cut -d '"' -f 2 | cut -c 1`
                ;;
            rhel|ol)
                codename=`cat /etc/*-release | grep -i 'red hat.*(' | \
                          sed 's/.*(\(.*\)).*/\1/' | head -1 | \
                          tr '[:upper:]' '[:lower:]'`
                # For Red Hat also grab release
                release=`cat /etc/*-release | grep -i 'red hat.*[0-9]' | \
                         sed 's/^[^0-9]*\([0-9][0-9]*\).*$/\1/' | head -1`

                if [ -z "$release" ]; then
                    release=`cat /etc/*-release | grep -i '^VERSION_ID=' | \
                             sed 's/^[^0-9]*\([0-9][0-9]*\).*$/\1/' | head -1`
                fi

                os="rhel"
                centos_flavor="red hat linux"
                ;;
            amzn)
                codename="amazon-linux-ami"
                release_amzn=`cat /etc/*-release | grep -i 'amazon.*[0-9]' | \
                              sed 's/^[^0-9]*\([0-9][0-9]*\.[0-9][0-9]*\).*$/\1/' | \
                              head -1`

                amzn=`rpm --eval "%{amzn}"`
                if [ ${amzn} == 1 ]; then
                    release="latest"
                else
                    release=${amzn}
                fi

                os="amzn"
                centos_flavor="amazon linux"
                ;;
            *)
                codename=""
                release=""
                ;;
        esac
    fi
}


# Check availability of specified major Python version (default is 2)
check_python() {
    printf "\033[32m ${step}. Checking Python ...\033[0m"

    case "$1" in
        3)
            pyver=3
            python_package_deb="python3"
            python_package_rpm="python3"
            command -V python3 > /dev/null 2>&1 && python_bin='python3'
            ;;
        *)
            pyver=2
            python_package_deb="python2.7"
            python_package_rpm="python"
            command -V python > /dev/null 2>&1 && python_bin='python'
            if [ -z "$python_bin" ]; then
                command -V python2 > /dev/null 2>&1 && python_bin='python2'
            fi
            if [ -z "$python_bin" ]; then
                command -V python2.7 > /dev/null 2>&1 && python_bin='python2.7'
            fi
            ;;
    esac

    if [ -z "${python_bin}" ]; then
        printf "\033[31m python ${pyver} required, could not be found.\033[0m\n\n"
        case "$os" in
            ubuntu|debian)
                printf "\033[32m Please check and install Python package:\033[0m\n\n"
                printf "     ${sudo_cmd}apt-cache pkgnames | grep ${python_package_deb}\n"
                printf "     ${sudo_cmd}apt-get install ${python_package_deb}\n\n"
                ;;
            centos|rhel|amzn)
                printf "\033[32m Please check and install Python package:\033[0m\n\n"
                printf "     ${sudo_cmd}yum list ${python_package_rpm}\n"
                printf "     ${sudo_cmd}yum install ${python_package_rpm}\n\n"
                ;;
        esac
        exit 1
    fi

    python_version=`${python_bin} -c 'import sys; print("{0}.{1}".format(sys.version_info[0], sys.version_info[1]))'`

    if [ $? -ne 0 ]; then
        printf "\033[31m failed to detect python version.\033[0m\n\n"
        exit 1
    fi

    case $pyver in
        2)
            if [ $(echo "$python_version" | tr -d '.') -lt 27 ]; then
                printf "\033[31m python 2 older than 2.7 is not supported.\033[0m\n\n"
                exit 1
            fi
            ;;
        3)
            if [ $(echo "$python_version" | tr -d '.') -lt 36 ]; then
                printf "\033[31m python 3 older than 3.6 is not supported.\033[0m\n\n"
                exit 1
            fi
            ;;
    esac

    printf "\033[32m found python $python_version\033[0m\n"
}

# Check what downloader is available
check_downloader() {
    if command -V curl > /dev/null 2>&1; then
        downloader="curl"
        downloader_opts="-fs"
    else
        if command -V wget > /dev/null 2>&1; then
            downloader="wget"
            downloader_opts="-q -O -"
        else
            printf "\033[31m no curl or wget found, exiting.\033[0m\n\n"
            exit 1
        fi
    fi
}

# Add public key for package verification (Ubuntu/Debian)
add_public_key_deb() {
    printf "\033[32m ${step}. Adding public key ...\033[0m"

    check_downloader && \
    ${downloader} ${downloader_opts} ${public_key_url} | \
    ${sudo_cmd} apt-key add - > /dev/null 2>&1

    if [ $? -ne 0 ]; then
        printf "\033[31m failed.\033[0m\n\n"
        exit 1
    else
        printf "\033[32m done.\033[0m\n"
    fi
}

# Add public key for package verification (CentOS/Red Hat)
add_public_key_rpm() {
    printf "\033[32m ${step}. Adding public key ...\033[0m"

    if command -V rpmkeys > /dev/null 2>&1; then
        rpm_key_cmd="rpmkeys"
    else
        rpm_key_cmd="rpm"
    fi

    check_downloader && \
    ${sudo_cmd} rm -f /tmp/nginx_signing.key.$$ && \
    ${downloader} ${downloader_opts} ${public_key_url} | \
    tee /tmp/nginx_signing.key.$$ > /dev/null 2>&1 && \
    ${sudo_cmd} ${rpm_key_cmd} --import /tmp/nginx_signing.key.$$ && \
    rm -f /tmp/nginx_signing.key.$$

    if [ $? -ne 0 ]; then
        printf "\033[31m failed.\033[0m\n\n"
        exit 1
    else
        printf "\033[32m done.\033[0m\n"
    fi
}

# Add repo configuration (apt - Ubuntu/Debian)
add_repo_deb () {
    printf "\033[32m ${step}. Adding repository ...\033[0m"

    if [ $1 -eq 3 ]; then
        packages_url=${packages_url}/py3/
    fi

    test -d /etc/apt/sources.list.d && \
    ${sudo_cmd} test -w /etc/apt/sources.list.d && \
    ${sudo_cmd} rm -f /etc/apt/sources.list.d/amplify-agent.list && \
    ${sudo_cmd} rm -f /etc/apt/sources.list.d/nginx-amplify.list && \
    echo "deb ${packages_url}/${os}/ ${codename} amplify-agent" | \
    ${sudo_cmd} tee /etc/apt/sources.list.d/nginx-amplify.list > /dev/null 2>&1 && \
    ${sudo_cmd} chmod 644 /etc/apt/sources.list.d/nginx-amplify.list > /dev/null 2>&1

    if [ $? -eq 0 ]; then
        printf "\033[32m added.\033[0m\n"
    else
        printf "\033[31m failed.\033[0m\n\n"
        exit 1
    fi
}

# Add repo configuration (yum - CentOS/RHEL/Amazon/Oracle)
add_repo_rpm () {
    printf "\033[32m ${step}. Adding repository config ...\033[0m"

    if [ $1 -eq 3 ]; then
        packages_url=${packages_url}/py3
    fi

    test -d /etc/yum.repos.d && \
    ${sudo_cmd} test -w /etc/yum.repos.d && \
    ${sudo_cmd} rm -f /etc/yum.repos.d/nginx-amplify.repo && \
    printf "[nginx-amplify]\nname=nginx amplify repo\nbaseurl=${packages_url}/${os}/${release}/\$basearch\ngpgcheck=1\nenabled=1\n" | \
    ${sudo_cmd} tee /etc/yum.repos.d/nginx-amplify.repo > /dev/null 2>&1 && \
    ${sudo_cmd} chmod 644 /etc/yum.repos.d/nginx-amplify.repo > /dev/null 2>&1

    if [ $? -eq 0 ]; then
        printf "\033[32m added.\033[0m\n"
    else
        printf "\033[31m failed.\033[0m\n\n"
        exit 1
    fi
}

# Install package (either deb or rpm)
install_deb_or_rpm() {
    # Update repo
    printf "\033[32m ${step}. Updating repository ...\n\n\033[0m"

    test -n "$update_cmd" && \
    ${sudo_cmd} ${update_cmd}

    if [ $? -eq 0 ]; then
        printf "\033[32m\n ${step}. Updating repository ... done.\033[0m\n"
    else
        printf "\033[31m\n ${step}. Updating repository ... failed.\033[0m\n\n"
        printf "\033[32m Please check the list of the supported systems here https://git.io/vKkev\033[0m\n\n"
        exit 1
    fi

    incr_step

    # Install package(s)
    printf "\033[32m ${step}. Installing nginx-amplify-agent package ...\033[0m\n\n"

    test -n "$package_name" && \
    test -n "$install_cmd" && \
    ${sudo_cmd} ${install_cmd} ${package_name}

    if [ $? -eq 0 ]; then
        printf "\033[32m\n ${step}. Installing nginx-amplify-agent package ... done.\033[0m\n"
    else
        printf "\033[31m\n ${step}. Installing nginx-amplify-agent package ... failed.\033[0m\n\n"
        printf "\033[32m Please check the list of the supported systems here https://git.io/vKkev\033[0m\n\n"
        exit 1
    fi
}

# Detect the user for the agent to use
detect_amplify_user() {
    if [ -f "${agent_conf_file}" ]; then
        amplify_user=`grep -v '#' ${agent_conf_file} | \
                      grep -A 5 -i '\[.*nginx.*\]' | \
                      grep -i 'user.*=' | \
                      awk -F= '{print $2}' | \
                      sed 's/ //g' | \
                      head -1`

        nginx_conf_file=`grep -A 5 -i '\[.*nginx.*\]' ${agent_conf_file} | \
                         grep -i 'configfile.*=' | \
                         awk -F= '{print $2}' | \
                         sed 's/ //g' | \
                         head -1`
    fi

    if [ -f "${nginx_conf_file}" ]; then
        nginx_user=`grep 'user[[:space:]]' ${nginx_conf_file} | \
                    grep -v '[#].*user.*;' | \
                    grep -v '_user' | \
                    sed -n -e 's/.*\(user[[:space:]][[:space:]]*[^;]*\);.*/\1/p' | \
                    awk '{ print $2 }' | head -1`
    fi

    if [ -z "${amplify_user}" ]; then
        test -n "${nginx_user}" && \
        amplify_user=${nginx_user} || \
        amplify_user="nginx"
    fi

    amplify_group=`id -gn ${amplify_user}`
}

incr_step() {
    step=`expr $step + 1`
    if [ "${step}" -lt 10 ]; then
        step=" ${step}"
    fi
}

#
# Main
#

assume_yes=""
errors=0

for arg in "$@"; do
    case "$arg" in
        -y)
            assume_yes="-y"
            ;;
        *)
            ;;
    esac
done

step=" 1"

printf "\n --- This script will install the NGINX Amplify Agent package ---\n\n"
printf "\033[32m ${step}. Checking admin user ...\033[0m"

sudo_found="no"
sudo_cmd=""

# Check if sudo is installed
if command -V sudo > /dev/null 2>&1; then
    sudo_found="yes"
    sudo_cmd="sudo "
fi

# Detect root
if [ "`id -u`" = "0" ]; then
    printf "\033[32m root, ok.\033[0m\n"
    sudo_cmd=""
else
    if [ "$sudo_found" = "yes" ]; then
        printf "\033[33m you'll need sudo rights.\033[0m\n"
    else
        printf "\033[31m not root, sudo not found, exiting.\033[0m\n"
        exit 1
    fi
fi

incr_step

# Add API key
printf "\033[32m ${step}. Checking API key ...\033[0m"

if [ -n "$API_KEY" ]; then
    api_key=$API_KEY
fi

if [ -z "$api_key" ]; then
    printf "\033[31m What's your API key? Please check the docs and the UI.\033[0m\n\n"
    exit 1
else
    printf "\033[32m using ${api_key}\033[0m\n"
fi

incr_step

# Write generated UUIDs to config if STORE_UUID is set to True

printf "\033[32m ${step}. Checking if uuid should be stored in the config ...\033[0m"

if [ -n "${STORE_UUID}" ]; then
    store_uuid=$STORE_UUID
fi

if [ "$store_uuid" != "True" ] && [ "$store_uuid" != "False" ]; then
    printf "\033[31m STORE_UUID needs to be True or False\033[0m\n\n"
    exit 1
else
    printf "\033[32m ${store_uuid}\033[0m\n"
fi

incr_step

# Get OS name and codename
get_os_name

# Check for supported OS
printf "\033[32m ${step}. Checking OS compatibility ...\033[0m"

# Add public key, create repo config, install package
case "$os" in
    ubuntu|debian)
        printf "\033[32m ${os} detected.\033[0m\n"
        incr_step

        case "$codename" in
            buster|bullseye|bookworm|bionic|focal|jammy|noble)
                check_python 3
                python_supported=3
                ;;
            *)
                check_python 2
                ;;
        esac

        incr_step

        # Install apt-transport-https if not found
        if ! dpkg -s apt-transport-https > /dev/null 2>&1; then
            printf "\033[32m ${step}. Installing apt-transport-https ...\033[0m"

            ${sudo_cmd} apt-get update > /dev/null 2>&1 && \
            ${sudo_cmd} apt-get -y install apt-transport-https > /dev/null 2>&1

            if [ $? -eq 0 ]; then
                printf "\033[32m done.\033[0m\n"
            else
                printf "\033[31m failed.\033[0m\n\n"
                exit 1
            fi

            incr_step
        fi

        # Add public key
        add_public_key_deb

        incr_step

        # Add repository configuration
        add_repo_deb $python_supported
        incr_step

        # Install package
        update_cmd="apt-get ${assume_yes} update"
        install_cmd="apt-get ${assume_yes} install"

        # Configure package version
        if [ -n "${VERSION}" ]; then
            package_name="${package_name}=${VERSION}"
        fi

        install_deb_or_rpm
        ;;
    centos|rhel|amzn)
        printf "\033[32m ${centos_flavor} detected.\033[0m\n"

        incr_step

        case "$os$release" in
            rhel8|rhel9|centos8|centos9|amzn2)
                check_python 3
                python_supported=3
                ;;
            *)
                check_python 2
                ;;
        esac

        incr_step

        # Add public key
        add_public_key_rpm

        incr_step

        # Add repository configuration
        add_repo_rpm $python_supported

        incr_step

        # Install package
        update_cmd="yum ${assume_yes} makecache"

        # Configure package version
        if [ -n "${VERSION}" ]; then
            package_name="${package_name}-${VERSION}"
        fi

        # Check if nginx packages are excluded
        if grep 'exclude.*nginx' /etc/yum.conf | grep -v '#' >/dev/null 2>&1; then
            printf "\n"
            printf "\033[32m Packages with the 'nginx' names are excluded in /etc/yum.conf - proceed with install (y/n)? \033[0m"

            read answer
            printf "\n"

            if [ "${answer}" = "y" -o "${answer}" = "Y" ]; then
                install_cmd="yum ${assume_yes} --disableexcludes=main install"
            else
                printf "\033[31m exiting.\033[0m\n"
                exit 1
            fi
        else
            install_cmd="yum ${assume_yes} install"
        fi

        install_deb_or_rpm
        ;;
    *)
        if [ -n "$os" ] && [ "$os" != "linux" ]; then
            printf "\033[31m $os is currently unsupported, apologies!\033[0m\n\n"
        else
            printf "\033[31m failed.\033[0m\n\n"
        fi

        exit 1
esac

incr_step

# Build config file from template
printf "\033[32m ${step}. Building configuration file ...\033[0m"

if [ ! -f "${agent_conf_file}.default" ]; then
    printf "\033[31m can't find ${agent_conf_file}.default\033[0m\n\n"
    exit 1
fi

if [ -f "${agent_conf_file}" ]; then
    receiver=`cat ${agent_conf_file} | grep -i receiver | sed 's/^.*= \([^ ][^ ]*\)$/\1/'`
    ${sudo_cmd} rm -f ${agent_conf_file}.old
    ${sudo_cmd} cp -p ${agent_conf_file} ${agent_conf_file}.old
fi

if [ -n "${AMPLIFY_HOSTNAME}" ]; then
    amplify_hostname="${AMPLIFY_HOSTNAME}"
fi

if [ -n "${API_URL}" ]; then
    api_url="${API_URL}"
    api_ping_url="${api_url}/ping/"
    api_receiver_url="${api_url}/1.4"
fi

${sudo_cmd} rm -f ${agent_conf_file} && \
${sudo_cmd} sh -c "sed -e 's|api_key.*$|api_key = $api_key|' \
                       -e 's|api_url.*$|api_url = $api_receiver_url|' \
                       -e 's|hostname.*$|hostname = $amplify_hostname|' \
                       -e 's|store_uuid.*$|store_uuid = $store_uuid|' \
        ${agent_conf_file}.default > \
        ${agent_conf_file}" && \
${sudo_cmd} chmod 644 ${agent_conf_file} && \
${sudo_cmd} chown nginx ${agent_conf_file} > /dev/null 2>&1

if [ $? -eq 0 ]; then
    printf "\033[32m done.\033[0m\n"
else
    printf "\033[31m failed.\033[0m\n\n"
    exit 1
fi

incr_step

# Detect the agent's euid
detect_amplify_user

test -n "${amplify_user}" && \
amplify_euid=`id -u ${amplify_user}`

if [ $? -eq 0 ]; then
    # Check is sudo can be used for tests
    printf "\033[32m ${step}. Checking if sudo -u ${amplify_user} -g ${amplify_group} can be used for tests ...\033[0m"

    if [ "${sudo_found}" = "yes" ]; then
        sudo_output=`sudo -u ${amplify_user} /bin/sh -c "id -un" 2>/dev/null`

        if [ "${sudo_output}" = "${amplify_user}" ]; then
            printf "\033[32m done.\033[0m\n"
        else
            printf "\033[31m failed. (${sudo_output} != ${amplify_user})\033[0m\n"
            errors=`expr $errors + 1`
        fi
    else
        printf "\033[31m failed, sudo not found.\033[0m\n"
        errors=`expr $errors + 1`
    fi

    incr_step
else
    printf "\n"
    printf "\033[31m Can't detect the agent's user id, skipping some tests.\033[0m\n\n"
    errors=`expr $errors + 1`
fi

# Check agent capabilities
if [ "${errors}" -eq 0 ]; then
    # Check if the agent is able to use ps(1)
    printf "\033[32m ${step}. Checking if euid ${amplify_euid}(${amplify_user}) can find root processes ...\033[0m"

    sudo -u ${amplify_user} -g ${amplify_group} /bin/sh -c "ps xao user,pid,ppid,command" 2>&1 | grep "^root" >/dev/null 2>&1

    if [ $? -eq 0 ]; then
        printf "\033[32m ok.\033[0m\n"
    else
        printf "\033[31m agent will fail to detect nginx, ps(1) is restricted!\033[0m\n"
        errors=`expr $errors + 1`
    fi

    incr_step

    printf "\033[32m ${step}. Checking if euid ${amplify_euid}(${amplify_user}) can access I/O counters for nginx ...\033[0m"

    sudo -u ${amplify_user} -g ${amplify_group} /bin/sh -c 'cat /proc/$$/io' >/dev/null 2>&1

    if [ $? -eq 0 ]; then
        printf "\033[32m ok.\033[0m\n"
    else
        printf "\033[31m failed, /proc/<pid>/io is restricted!\033[0m\n"
        errors=`expr $errors + 1`
    fi

    incr_step
fi

# Check nginx.conf for stub_status
if [ -f "${nginx_conf_file}" ]; then
    nginx_conf_dir=`echo ${nginx_conf_file} | sed 's/^\(.*\)\/[^/]*/\1/'`

    if [ -d "${nginx_conf_dir}" ]; then
        printf "\033[32m ${step}. Checking if stub_status is configured ...\033[0m"

        if ${sudo_cmd} grep -R "stub_status" ${nginx_conf_dir}/* > /dev/null 2>&1; then
            printf "\033[32m ok.\033[0m\n"
        else
            printf "\033[31m no stub_status in nginx config, please check https://git.io/vQGs4\033[0m\n"
            errors=`expr $errors + 1`
        fi

        incr_step
    fi
fi

# Test connectivity to receiver, and system time too
if [ -n "${downloader}" ]; then
    printf "\033[32m ${step}. Checking connectivity to the receiver ...\033[0m"

    if ${downloader} ${downloader_opts} ${api_ping_url} | grep 'pong' >/dev/null 2>&1; then
        printf "\033[32m ok.\033[0m\n"

        incr_step

        # Compare server time with local time
        printf "\033[32m ${step}. Checking system time ...\033[0m"
        if [ "${downloader}" = "curl" ]; then
            downloader_opts="-fsi"
        else
            if [ "${downloader}" = "wget" ]; then
                downloader_opts="-qS"
            fi
        fi

        server_date=`${downloader} ${downloader_opts} ${api_ping_url} 2>&1 | grep '^.*Date' | sed 's/.*Date:[ ][ ]*\(.*\)/\1/'`

        if [ $? -eq 0 ]; then
            amplify_epoch=`date --date="${server_date}" "+%s"`
            agent_epoch=`date -u '+%s'`
            offset=`expr ${amplify_epoch} - ${agent_epoch} | sed 's/^-//'`

            if [ "${offset}" -le 6 ]; then
                printf "\033[32m ok.\033[0m\n"
            else
                printf "\033[31m please adjust the system clock for proper metric collection!\033[0m\n"
                errors=`expr $errors + 1`
            fi
        else
            printf "\033[31m failed!\033[0m\n"
            errors=`expr $errors + 1`
        fi

    else
        printf "\033[31m failed to connect to the receiver! (check https://git.io/vKk0I)\033[0m\n"
        errors=`expr $errors + 1`
    fi
fi

incr_step

printf "\n"

# Finalize install
if [ "$errors" -eq 0 ]; then
    printf "\033[32m OK, everything went just fine!\033[0m\n\n"
else
    printf "\033[31m A few checks have failed - please read the warnings above!\033[0m\n\n"
fi

printf "\033[32m To start and stop the Amplify Agent type:\033[0m\n\n"
printf "     \033[7m${sudo_cmd}service amplify-agent { start | stop }\033[0m\n\n"

printf "\033[32m Amplify Agent log can be found here:\033[0m\n"
printf "     /var/log/amplify-agent/agent.log\n\n"

printf "\033[32m After the agent is launched, it takes a couple of minutes for this system to appear\033[0m\n"
printf "\033[32m in the Amplify user interface.\033[0m\n\n"

printf "\033[32m PLEASE CHECK THE DOCUMENTATION HERE:\033[0m\n"
printf "     https://amplify.nginx.com/docs/\n\n"

# Check for an older version of the agent running
if [ -f "${amplify_pid_file}" ]; then
    amplify_pid=`cat ${amplify_pid_file}`

    if ps "${amplify_pid}" >/dev/null 2>&1; then
        printf "\033[32m Stopping old amplify-agent, pid ${amplify_pid}\033[0m\n"
        ${sudo_cmd} service amplify-agent stop > /dev/null 2>&1 < /dev/null
    fi
fi

# Launch agent
printf "\033[32m Launching amplify-agent ...\033[0m\n"
${sudo_cmd} service amplify-agent start > /dev/null 2>&1 < /dev/null

if [ $? -eq 0 ]; then
    printf "\033[32m All done.\033[0m\n\n"
else
    printf "\n"
    printf "\033[31m Couldn't start the agent, please check /var/log/amplify-agent/agent.log\033[0m\n\n"
    exit 1
fi

exit 0