#!/usr/bin/env bash

# reload the user profile
[ -f /etc/profile ] && . /etc/profile

export PATH="${PATH}:/sbin:/usr/sbin:/usr/local/bin:/usr/local/sbin"

# fix PKG_CHECK_MODULES error
if [ -d /usr/share/aclocal ]
then
        ACLOCAL_PATH=${ACLOCAL_PATH-/usr/share/aclocal}
        export ACLOCAL_PATH
fi

LC_ALL=C
umask 022

# you can set CFLAGS before running installer
CFLAGS="${CFLAGS--O3}"

# keep a log of this command
printf "\n# " >>netdata-installer.log
date >>netdata-installer.log
printf "CFLAGS=\"%s\" " "${CFLAGS}" >>netdata-installer.log
printf "%q " "$0" "${@}" >>netdata-installer.log
printf "\n" >>netdata-installer.log

REINSTALL_PWD="${PWD}"
REINSTALL_COMMAND="$(printf "%q " "$0" "${@}"; printf "\n")"

banner() {
    local   l1="  ^"                                                                      \
            l2="  |.-.   .-.   .-.   .-.   .-.   .-.   .-.   .-.   .-.   .-.   .-.   .-.   .-"  \
            l3="  |   '-'   '-'   '-'   '-'   '-'   '-'   '-'   '-'   '-'   '-'   '-'   '-'  "  \
            l4="  +----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+--->" \
            sp="                                                                        " \
            netdata="netdata" start end msg="${*}"

    [ ${#msg} -lt ${#netdata} ] && msg="${msg}${sp:0:$(( ${#netdata} - ${#msg}))}"
    [ ${#msg} -gt $(( ${#l2} - 20 )) ] && msg="${msg:0:$(( ${#l2} - 23 ))}..."

    start="$(( ${#l2} / 2 - 4 ))"
    [ $(( start + ${#msg} + 4 )) -gt ${#l2} ] && start=$((${#l2} - ${#msg} - 4))
    end=$(( ${start} + ${#msg} + 4 ))

    echo >&2
    echo >&2 "${l1}"
    echo >&2 "${l2:0:start}${sp:0:2}${netdata}${sp:0:$((end - start - 2 - ${#netdata}))}${l2:end:$((${#l2} - end))}"
    echo >&2 "${l3:0:start}${sp:0:2}${msg}${sp:0:2}${l3:end:$((${#l2} - end))}"
    echo >&2 "${l4}"
    echo >&2
}

service="$(which service 2>/dev/null || command -v service 2>/dev/null)"
systemctl="$(which systemctl 2>/dev/null || command -v systemctl 2>/dev/null)"
service() {
    local cmd="${1}" action="${2}"

    if [ ! -z "${service}" ]
    then
        run "${service}" "${cmd}" "${action}"
        return $?
    elif [ ! -z "${systemctl}" ]
    then
        run "${systemctl}" "${action}" "${cmd}"
        return $?
    fi
    return 1
}

ME="$0"
DONOTSTART=0
DONOTWAIT=0
NETDATA_PREFIX=
LIBS_ARE_HERE=0

usage() {
    banner "installer command line options"
    cat <<USAGE

${ME} <installer options>

Valid <installer options> are:

   --install /PATH/TO/INSTALL

        If your give: --install /opt
        netdata will be installed in /opt/netdata

   --dont-start-it

        Do not (re)start netdata.
        Just install it.

   --dont-wait

        Do not wait for the user to press ENTER.
        Start immediately building it.

   --zlib-is-really-here
   --libs-are-really-here

        If you get errors about missing zlib,
        or libuuid but you know it is available,
        you have a broken pkg-config.
        Use this option to allow it continue
        without checking pkg-config.

Netdata will by default be compiled with gcc optimization -O3
If you need to pass different CFLAGS, use something like this:

  CFLAGS="<gcc options>" ${ME} <installer options>

For the installer to complete successfully, you will need
these packages installed:

   gcc make autoconf automake pkg-config zlib1g-dev (or zlib-devel)
   uuid-dev (or libuuid-devel)

For the plugins, you will at least need:

   curl nodejs

USAGE
}

md5sum="$(which md5sum 2>/dev/null || command -v md5sum 2>/dev/null)"
get_git_config_signatures() {
    local x s file md5

    [ ! -d "conf.d" ] && echo >&2 "Wrong directory." && return 1
    [ -z "${md5sum}" -o ! -x "${md5sum}" ] && echo >&2 "No md5sum command." && return 1

    echo >configs.signatures.tmp

    for x in $(find conf.d -name \*.conf)
    do
            x="${x/conf.d\//}"
            echo "${x}"
            for c in $(git log --follow "conf.d/${x}" | grep ^commit | cut -d ' ' -f 2)
            do
                    git checkout ${c} "conf.d/${x}" || continue
                    s="$(cat "conf.d/${x}" | md5sum | cut -d ' ' -f 1)"
                    echo >>configs.signatures.tmp "${x}:${s}"
                    echo "    ${s}"
            done
            git checkout HEAD "conf.d/${x}" || break
    done

    cat configs.signatures.tmp |\
        grep -v "^$" |\
        sort -u |\
        {
            echo "declare -A configs_signatures=("
            IFS=":"
            while read file md5
            do
                echo "  ['${md5}']='${file}'"
            done
            echo ")"
        } >configs.signatures

    rm configs.signatures.tmp

    return 0
}


while [ ! -z "${1}" ]
do
    if [ "$1" = "--install" ]
        then
        NETDATA_PREFIX="${2}/netdata"
        shift 2
    elif [ "$1" = "--zlib-is-really-here" -o "$1" = "--libs-are-really-here" ]
        then
        LIBS_ARE_HERE=1
        shift 1
    elif [ "$1" = "--dont-start-it" ]
        then
        DONOTSTART=1
        shift 1
    elif [ "$1" = "--dont-wait" ]
        then
        DONOTWAIT=1
        shift 1
    elif [ "$1" = "--help" -o "$1" = "-h" ]
        then
        usage
        exit 1
    elif [ "$1" = "get_git_config_signatures" ]
        then
        get_git_config_signatures && exit 0
        exit 1
    else
        echo >&2
        echo >&2 "ERROR:"
        echo >&2 "I cannot understand option '$1'."
        usage
        exit 1
    fi
done

banner "real-time performance monitoring, done right!"
cat <<BANNER

  You are about to build and install netdata to your system.

  It will be installed at these locations:

   - the daemon    at ${NETDATA_PREFIX}/usr/sbin/netdata
   - config files  at ${NETDATA_PREFIX}/etc/netdata
   - web files     at ${NETDATA_PREFIX}/usr/share/netdata
   - plugins       at ${NETDATA_PREFIX}/usr/libexec/netdata
   - cache files   at ${NETDATA_PREFIX}/var/cache/netdata
   - db files      at ${NETDATA_PREFIX}/var/lib/netdata
   - log files     at ${NETDATA_PREFIX}/var/log/netdata
   - pid file      at ${NETDATA_PREFIX}/var/run

  This installer allows you to change the installation path.
  Press Control-C and run the same command with --help for help.

BANNER

if [ "${UID}" -ne 0 ]
    then
    if [ -z "${NETDATA_PREFIX}" ]
        then
        banner "wrong command line options!"
        cat <<NONROOTNOPREFIX

Sorry! This will fail!

You are attempting to install netdata as non-root, but you plan to install it
in system paths.

Please set an installation prefix, like this:

    $0 ${@} --install /tmp

or, run the installer as root:

    sudo $0 ${@}

We suggest to install it as root, or certain data collectors will not be able
to work. Netdata drops root privileges when running. So, if you plan to keep
it, install it as root to get the full functionality.

NONROOTNOPREFIX
        exit 1

    else
        cat <<NONROOT

IMPORTANT:
You are about to install netdata as a non-root user.
Netdata will work, but a few data collection modules that
require root access will fail.

If you installing permanently on your system, run the
installer like this:

    sudo $0 ${@}

NONROOT
    fi
fi

have_autotools=
if [ "$(type autoreconf 2> /dev/null)" ]
then
    autoconf_maj_min() {
        local maj min IFS=.-

        maj=$1
        min=$2

        set -- $(autoreconf -V | sed -ne '1s/.* \([^ ]*\)$/\1/p')
        eval $maj=\$1 $min=\$2
    }
    autoconf_maj_min AMAJ AMIN

    if [ "$AMAJ" -gt 2 ]
    then
        have_autotools=Y
    elif [ "$AMAJ" -eq 2 -a "$AMIN" -ge 60 ]
    then
        have_autotools=Y
    else
        echo "Found autotools $AMAJ.$AMIN"
    fi
else
    echo "No autotools found"
fi

if [ ! "$have_autotools" ]
then
    if [ -f configure ]
    then
        echo "Will skip autoreconf step"
    else
        banner "autotools v2.60 required"
        cat <<"EOF"

-------------------------------------------------------------------------------
autotools 2.60 or later is required

Sorry, you do not seem to have autotools 2.60 or later, which is
required to build from the git sources of netdata.

You can either install a suitable version of autotools and automake
or download a netdata package which does not have these dependencies.

Source packages where autotools have already been run are available
here:
       https://firehol.org/download/netdata/

The unsigned/master folder tracks the head of the git tree and released
packages are also available.
EOF
        exit 1
    fi
fi

if [ ${DONOTWAIT} -eq 0 ]
    then
    if [ ! -z "${NETDATA_PREFIX}" ]
        then
        read -p "Press ENTER to build and install netdata to '${NETDATA_PREFIX}' > "
    else
        read -p "Press ENTER to build and install netdata to your system > "
    fi
fi

build_error() {
    banner "sorry, it failed to build..."
    cat <<EOF

^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Sorry! netdata failed to build...

You many need to check these:

1. The package uuid-dev (or libuuid-devel) has to be installed.

   If your system cannot find libuuid, although it is installed
   run me with the option:  --libs-are-really-here

2. The package zlib1g-dev (or zlib-devel) has to be installed.

   If your system cannot find zlib, although it is installed
   run me with the option:  --libs-are-really-here

3. You need basic build tools installed, like:

   gcc make autoconf automake pkg-config

   Autoconf version 2.60 or higher is required.

If you still cannot get it to build, ask for help at github:

   https://github.com/firehol/netdata/issues


EOF
    trap - EXIT
    exit 1
}

run() {
    printf >>netdata-installer.log "# "
    printf >>netdata-installer.log "%q " "${@}"
    printf >>netdata-installer.log " ... "

    printf >&2 "\n"
    printf >&2 ":-----------------------------------------------------------------------------\n"
    printf >&2 "Running command:\n"
    printf >&2 "\n"
    printf >&2 "%q " "${@}"
    printf >&2 "\n"

    "${@}"

    local ret=$?
    if [ ${ret} -ne 0 ]
        then
        printf >>netdata-installer.log "FAILED!\n"
    else
        printf >>netdata-installer.log "OK\n"
    fi

    return ${ret}
}

if [ ${LIBS_ARE_HERE} -eq 1 ]
    then
    shift
    echo >&2 "ok, assuming libs are really installed."
    export ZLIB_CFLAGS=" "
    export ZLIB_LIBS="-lz"
    export UUID_CFLAGS=" "
    export UUID_LIBS="-luuid"
fi

trap build_error EXIT

if [ "$have_autotools" ]
then
    run ./autogen.sh || exit 1
fi

run ./configure \
    --prefix="${NETDATA_PREFIX}/usr" \
    --sysconfdir="${NETDATA_PREFIX}/etc" \
    --localstatedir="${NETDATA_PREFIX}/var" \
    --with-zlib --with-math --with-user=netdata \
    CFLAGS="${CFLAGS}" || exit 1

# remove the build_error hook
trap - EXIT

if [ -f src/netdata ]
    then
    echo >&2 "Cleaning a possibly old compilation ..."
    run make clean
fi

echo >&2 "Compiling netdata ..."
run make || exit 1

if [ "${BASH_VERSINFO[0]}" -ge "4" ]
then
    declare -A configs_signatures=()
    if [ -f "configs.signatures" ]
        then
        source "configs.signatures" || echo >&2 "ERROR: Failed to load configs.signatures !"
    fi
fi

# migrate existing configuration files
# for node.d and charts.d
if [ -d "${NETDATA_PREFIX}/etc/netdata" ]
    then
    # the configuration directory exists

    if [ ! -d "${NETDATA_PREFIX}/etc/netdata/charts.d" ]
        then
        run mkdir "${NETDATA_PREFIX}/etc/netdata/charts.d"
    fi

    # move the charts.d config files
    for x in apache ap cpu_apps cpufreq example exim hddtemp load_average mem_apps mysql nginx nut opensips phpfpm postfix sensors squid tomcat
    do
        for y in "" ".old" ".orig"
        do
            if [ -f "${NETDATA_PREFIX}/etc/netdata/${x}.conf${y}" -a ! -f "${NETDATA_PREFIX}/etc/netdata/charts.d/${x}.conf${y}" ]
                then
                run mv -f "${NETDATA_PREFIX}/etc/netdata/${x}.conf${y}" "${NETDATA_PREFIX}/etc/netdata/charts.d/${x}.conf${y}"
            fi
        done
    done

    if [ ! -d "${NETDATA_PREFIX}/etc/netdata/node.d" ]
        then
        run mkdir "${NETDATA_PREFIX}/etc/netdata/node.d"
    fi

    # move the node.d config files
    for x in named sma_webbox snmp
    do
        for y in "" ".old" ".orig"
        do
            if [ -f "${NETDATA_PREFIX}/etc/netdata/${x}.conf${y}" -a ! -f "${NETDATA_PREFIX}/etc/netdata/node.d/${x}.conf${y}" ]
                then
                run mv -f "${NETDATA_PREFIX}/etc/netdata/${x}.conf${y}" "${NETDATA_PREFIX}/etc/netdata/node.d/${x}.conf${y}"
            fi
        done
    done
fi

# backup user configurations
installer_backup_suffix="${PID}.${RANDOM}"
for x in $(find "${NETDATA_PREFIX}/etc/netdata/" -name '*.conf' -type f)
do
    if [ -f "${x}" ]
        then
        # make a backup of the configuration file
        cp -p "${x}" "${x}.old"

        if [ -z "${md5sum}" -o ! -x "${md5sum}" ]
            then
            # we don't have md5sum - keep it
            cp -p "${x}" "${x}.installer_backup.${installer_backup_suffix}"
        else
            # find it relative filename
            f="${x/*\/etc\/netdata\//}"

            # find its checksum
            md5="$(cat "${x}" | ${md5sum} | cut -d ' ' -f 1)"

            # copy the original
            if [ -f "conf.d/${f}" ]
                then
                cp "conf.d/${f}" "${x}.orig"
            fi

            if [ "${BASH_VERSINFO[0]}" -ge "4" ]
            then
                if [ "${configs_signatures[${md5}]}" = "${f}" ]
                then
                    # it is a stock version - don't keep it
                    echo >&2 "File '${x}' is stock version."
                else
                    # edited by user - keep it
                    echo >&2 "File '${x}' has been edited by user."
                    cp -p "${x}" "${x}.installer_backup.${installer_backup_suffix}"
                fi
            else
                echo >&2 "File '${x}' cannot be check for custom edits."
                cp -p "${x}" "${x}.installer_backup.${installer_backup_suffix}"
            fi
        fi

    elif [ -f "${x}.installer_backup.${installer_backup_suffix}" ]
        then
        rm -f "${x}.installer_backup.${installer_backup_suffix}"
    fi
done

echo >&2 "Installing netdata ..."
run make install || exit 1

# restore user configurations
for x in $(find "${NETDATA_PREFIX}/etc/netdata/" -name '*.conf' -type f)
do
    if [ -f "${x}.installer_backup.${installer_backup_suffix}" ]
        then
        cp -p "${x}.installer_backup.${installer_backup_suffix}" "${x}"
        rm -f "${x}.installer_backup.${installer_backup_suffix}"
    fi
done

NETDATA_ADDED_TO_DOCKER=0
if [ ${UID} -eq 0 ]
    then
    getent group netdata > /dev/null
    if [ $? -ne 0 ]
        then
        echo >&2 "Adding netdata user group ..."
        run groupadd -r netdata
    fi

    getent passwd netdata > /dev/null
    if [ $? -ne 0 ]
        then
        echo >&2 "Adding netdata user account ..."
        run useradd -r -g netdata -c netdata -s $(which nologin || echo '/bin/false') -d / netdata
    fi

    getent group docker > /dev/null
    if [ $? -eq 0 ]
        then
        # find the users in the docker group
        docker=$(getent group docker | cut -d ':' -f 4)
        if [[ ",${docker}," =~ ,netdata, ]]
            then
            # netdata is already there
            :
        else
            # netdata is not in docker group
            echo >&2 "Adding netdata user to the docker group (needed to get container names) ..."
            run usermod -a -G docker netdata
        fi
        # let the uninstall script know
        NETDATA_ADDED_TO_DOCKER=1
    fi

    if [ -d /etc/logrotate.d -a ! -f /etc/logrotate.d/netdata ]
        then
        echo >&2 "Adding netdata logrotate configuration ..."
        run cp system/netdata.logrotate /etc/logrotate.d/netdata
    fi
fi


# -----------------------------------------------------------------------------
# load options from the configuration file

# create an empty config if it does not exist
[ ! -f "${NETDATA_PREFIX}/etc/netdata/netdata.conf" ] && touch "${NETDATA_PREFIX}/etc/netdata/netdata.conf"

# function to extract values from the config file
config_option() {
    local key="${1}" value="${2}" line=

    if [ -s "${NETDATA_PREFIX}/etc/netdata/netdata.conf" ]
        then
        line="$( grep "^[[:space:]]*${key}[[:space:]]*=[[:space:]]*" "${NETDATA_PREFIX}/etc/netdata/netdata.conf" | head -n 1 )"
        [ ! -z "${line}" ] && value="$( echo "${line}" | cut -d '=' -f 2 | sed -e "s/^[[:space:]]\+//g" -e "s/[[:space:]]\+$//g" )"
    fi

    echo "${value}"
}

# user
defuser="netdata"
[ ! "${UID}" = "0" ] && defuser="${USER}"
NETDATA_USER="$( config_option "run as user" "${defuser}" )"

NETDATA_WEB_USER="$( config_option "web files owner" "${defuser}" )"
NETDATA_WEB_GROUP="$( config_option "web files group" "${NETDATA_WEB_USER}" )"

# debug flags
defdebug=0
NETDATA_DEBUG="$( config_option "debug flags" ${defdebug} )"

# port
defport=19999
NETDATA_PORT="$( config_option "default port" ${defport} )"
NETDATA_PORT2="$( config_option "port" ${defport} )"

if [ "${NETDATA_PORT}" != "${NETDATA_PORT2}" ]
then
    if [ "${NETDATA_PORT2}" != "${defport}" ]
    then
        NETDATA_PORT="${NETDATA_PORT2}"
    fi
fi

# directories
NETDATA_LIB_DIR="$( config_option "lib directory" "${NETDATA_PREFIX}/var/lib/netdata" )"
NETDATA_CACHE_DIR="$( config_option "cache directory" "${NETDATA_PREFIX}/var/cache/netdata" )"
NETDATA_WEB_DIR="$( config_option "web files directory" "${NETDATA_PREFIX}/usr/share/netdata/web" )"
NETDATA_LOG_DIR="$( config_option "log directory" "${NETDATA_PREFIX}/var/log/netdata" )"
NETDATA_CONF_DIR="$( config_option "config directory" "${NETDATA_PREFIX}/etc/netdata" )"
NETDATA_RUN_DIR="${NETDATA_PREFIX}/var/run"


# -----------------------------------------------------------------------------
# prepare the directories

# this is needed if NETDATA_PREFIX is not empty
if [ ! -d "${NETDATA_RUN_DIR}" ]
    then
    mkdir -p "${NETDATA_RUN_DIR}" || exit 1
fi

echo >&2
echo >&2 "Fixing directories (user: ${NETDATA_USER})..."
for x in "${NETDATA_WEB_DIR}" "${NETDATA_CONF_DIR}" "${NETDATA_CACHE_DIR}" "${NETDATA_LOG_DIR}" "${NETDATA_LIB_DIR}" "${NETDATA_CONF_DIR}/python.d" "${NETDATA_CONF_DIR}/charts.d" "${NETDATA_CONF_DIR}/node.d"
do
    if [ ! -d "${x}" ]
        then
        echo >&2 "Creating directory '${x}'"
        run mkdir -p "${x}" || exit 1
    fi

    if [ ${UID} -eq 0 ]
        then
        if [ "${x}" = "${NETDATA_WEB_DIR}" ]
            then
            run chown -R "${NETDATA_WEB_USER}:${NETDATA_WEB_GROUP}" "${x}" || echo >&2 "WARNING: Cannot change the ownership of the files in directory ${x} to ${NETDATA_WEB_USER}:${NETDATA_WEB_GROUP}..."
        else
            run chown -R "${NETDATA_USER}:${NETDATA_USER}" "${x}" || echo >&2 "WARNING: Cannot change the ownership of the files in directory ${x} to ${NETDATA_USER}..."
        fi
    fi

    run chmod 0755 "${x}" || echo >&2 "WARNING: Cannot change the permissions of the directory ${x} to 0755..."
done

if [ ${UID} -eq 0 ]
    then
    run chown root "${NETDATA_PREFIX}/usr/libexec/netdata/plugins.d/apps.plugin"
    run chmod 0755 "${NETDATA_PREFIX}/usr/libexec/netdata/plugins.d/apps.plugin"
    run setcap cap_dac_read_search,cap_sys_ptrace+ep "${NETDATA_PREFIX}/usr/libexec/netdata/plugins.d/apps.plugin"
    if [ $? -ne 0 ]
        then
        # fix apps.plugin to be setuid to root
        run chown root "${NETDATA_PREFIX}/usr/libexec/netdata/plugins.d/apps.plugin"
        run chmod 4755 "${NETDATA_PREFIX}/usr/libexec/netdata/plugins.d/apps.plugin"
    fi
fi

# -----------------------------------------------------------------------------
# check if we can re-start netdata

if [ ${DONOTSTART} -eq 1 ]
    then
    if [ ! -s "${NETDATA_PREFIX}/etc/netdata/netdata.conf" ]
        then
        echo >&2 "Generating empty config file in: ${NETDATA_PREFIX}/etc/netdata/netdata.conf"
        echo "# Get config from http://127.0.0.1:${NETDATA_PORT}/netdata.conf" >"${NETDATA_PREFIX}/etc/netdata/netdata.conf"

        if [ "${UID}" -eq 0 ]
            then
            chown "${NETDATA_USER}" "${NETDATA_PREFIX}/etc/netdata/netdata.conf"
        fi
        chmod 0664 "${NETDATA_PREFIX}/etc/netdata/netdata.conf"
    fi
    banner "is installed now!"
    echo >&2 "  enjoy real-time performance and health monitoring..."
    exit 0
fi

# -----------------------------------------------------------------------------
# stop a running netdata

isnetdata() {
    [ -z "$1" -o ! -f "/proc/$1/stat" ] && return 1
    [ "$(cat "/proc/$1/stat" | cut -d '(' -f 2 | cut -d ')' -f 1)" = "netdata" ] && return 0
    return 1
}

stop_netdata_on_pid() {
    local pid="$1" ret=0 count=0

    isnetdata $pid || return 0

    printf >&2 "Stopping netdata on pid $pid ..."
    while [ ! -z "$pid" -a $ret -eq 0 ]
    do
        if [ $count -gt 45 ]
            then
            echo >&2 "Cannot stop the running netdata on pid $pid."
            return 1
        fi

        count=$(( count + 1 ))

        run kill $pid 2>/dev/null
        ret=$?

        test $ret -eq 0 && printf >&2 "." && sleep 2
    done

    echo >&2
    if [ $ret -eq 0 ]
    then
        echo >&2 "SORRY! CANNOT STOP netdata ON PID $pid !"
        return 1
    fi

    echo >&2 "netdata on pid $pid stopped."
    return 0
}

stop_all_netdata() {
    local p

    echo >&2 "Stopping a (possibly) running netdata..."

    for p in $(cat "${NETDATA_RUN_DIR}/netdata.pid" 2>/dev/null) \
        $(cat /var/run/netdata.pid 2>/dev/null) \
        $(cat /var/run/netdata/netdata.pid 2>/dev/null) \
        $(pidof netdata 2>/dev/null)
    do
        stop_netdata_on_pid $p
    done
}

# -----------------------------------------------------------------------------
# check netdata for systemd

issystemd() {
    # if the directory /etc/systemd/system does not exit, it is not systemd
    [ ! -d /etc/systemd/system ] && return 1

    # if pid 1 is systemd, it is systemd
    [ "$(basename $(readlink /proc/1/exe) 2>/dev/null)" = "systemd" ] && return 0

    # if systemd is running, it is systemd
    pidof systemd >/dev/null 2>&1 && return 0

    # else, it is not systemd
    return 1
}

started=0
if [ "${UID}" -eq 0 ]
    then

    if issystemd
    then
        # systemd is running on this system

        if [ ! -f /etc/systemd/system/netdata.service ]
        then
            echo >&2 "Installing systemd service..."
            run cp system/netdata.service /etc/systemd/system/netdata.service && \
                run systemctl daemon-reload && \
                run systemctl enable netdata
        else
            service netdata stop
        fi

        stop_all_netdata
        service netdata restart && started=1
    fi

    if [ ${started} -eq 0 ]
    then
        # check if we can use the system service
        service netdata stop
        stop_all_netdata
        service netdata restart && started=1
        if [ ${started} -eq 0 ]
        then
            service netdata start && started=1
        fi
    fi
fi

if [ ${started} -eq 0 ]
then
    # still not started...

    stop_all_netdata

    echo >&2 "Starting netdata..."
    run ${NETDATA_PREFIX}/usr/sbin/netdata -P ${NETDATA_RUN_DIR}/netdata.pid "${@}"
    if [ $? -ne 0 ]
        then
        echo >&2
        echo >&2 "SORRY! FAILED TO START NETDATA!"
        exit 1
    else
        echo >&2 "OK. NetData Started!"
    fi

    echo >&2
fi

# -----------------------------------------------------------------------------
# save a config file, if it is not already there

if [ ! -s "${NETDATA_PREFIX}/etc/netdata/netdata.conf" ]
    then
    echo >&2
    echo >&2 "-------------------------------------------------------------------------------"
    echo >&2
    echo >&2 "Downloading default configuration from netdata..."
    sleep 5

    # remove a possibly obsolete download
    [ -f "${NETDATA_PREFIX}/etc/netdata/netdata.conf.new" ] && rm "${NETDATA_PREFIX}/etc/netdata/netdata.conf.new"

    # disable a proxy to get data from the local netdata
    export http_proxy=
    export https_proxy=

    # try wget
    wget 2>/dev/null -O "${NETDATA_PREFIX}/etc/netdata/netdata.conf.new" "http://localhost:${NETDATA_PORT}/netdata.conf"
    ret=$?

    # try curl
    if [ $ret -ne 0 -o ! -s "${NETDATA_PREFIX}/etc/netdata/netdata.conf.new" ]
        then
        curl -s -o "${NETDATA_PREFIX}/etc/netdata/netdata.conf.new" "http://localhost:${NETDATA_PORT}/netdata.conf"
        ret=$?
    fi

    if [ $ret -eq 0 -a -s "${NETDATA_PREFIX}/etc/netdata/netdata.conf.new" ]
        then
        mv "${NETDATA_PREFIX}/etc/netdata/netdata.conf.new" "${NETDATA_PREFIX}/etc/netdata/netdata.conf"
        echo >&2 "New configuration saved for you to edit at ${NETDATA_PREFIX}/etc/netdata/netdata.conf"

        if [ "${UID}" -eq 0 ]
            then
            chown "${NETDATA_USER}" "${NETDATA_PREFIX}/etc/netdata/netdata.conf"
        fi
        chmod 0664 "${NETDATA_PREFIX}/etc/netdata/netdata.conf"
    else
        echo >&2 "Cannnot download configuration from netdata daemon using url 'http://localhost:${NETDATA_PORT}/netdata.conf'"
        [ -f "${NETDATA_PREFIX}/etc/netdata/netdata.conf.new" ] && rm "${NETDATA_PREFIX}/etc/netdata/netdata.conf.new"
    fi
fi

# -----------------------------------------------------------------------------
# Check for KSM

ksm_is_available_but_disabled() {
    cat <<KSM1

-------------------------------------------------------------------------------
Memory de-duplication instructions

You have kernel memory de-duper (called Kernel Same-page Merging,
or KSM) available, but it is not currently enabled.

To enable it run:

echo 1 >/sys/kernel/mm/ksm/run
echo 1000 >/sys/kernel/mm/ksm/sleep_millisecs

If you enable it, you will save 40-60% of netdata memory.

KSM1
}

ksm_is_not_available() {
    cat <<KSM2

-------------------------------------------------------------------------------
Memory de-duplication not present in your kernel

It seems you do not have kernel memory de-duper (called Kernel Same-page
Merging, or KSM) available.

To enable it, you need a kernel built with CONFIG_KSM=y

If you can have it, you will save 40-60% of netdata memory.

KSM2
}

if [ -f "/sys/kernel/mm/ksm/run" ]
    then
    if [ $(cat "/sys/kernel/mm/ksm/run") != "1" ]
        then
        ksm_is_available_but_disabled
    fi
else
    ksm_is_not_available
fi

# -----------------------------------------------------------------------------
# Check for version.txt

if [ ! -s web/version.txt ]
    then
    cat <<VERMSG

-------------------------------------------------------------------------------
Version update check warning

The way you downloaded netdata, we cannot find its version. This means the
Update check on the dashboard, will not work.

If you want to have version update check, please re-install it
following the procedure in:

https://github.com/firehol/netdata/wiki/Installation

VERMSG
fi

# -----------------------------------------------------------------------------
# apps.plugin warning

if [ "${UID}" -ne 0 ]
    then
    cat <<SETUID_WARNING

-------------------------------------------------------------------------------
apps.plugin needs privileges

Since you have installed netdata as a normal user, to have apps.plugin collect
all the needed data, you have to give it the access rights it needs, by running
either of the following sets of commands:

To run apps.plugin with escalated capabilities:

    sudo chown root:${NETDATA_USER} "${NETDATA_PREFIX}/usr/libexec/netdata/plugins.d/apps.plugin"
    sudo chmod 0750 "${NETDATA_PREFIX}/usr/libexec/netdata/plugins.d/apps.plugin"
    sudo setcap cap_dac_read_search,cap_sys_ptrace+ep "${NETDATA_PREFIX}/usr/libexec/netdata/plugins.d/apps.plugin"

or, to run apps.plugin as root:

    sudo chown root "${NETDATA_PREFIX}/usr/libexec/netdata/plugins.d/apps.plugin"
    sudo chmod 4755 "${NETDATA_PREFIX}/usr/libexec/netdata/plugins.d/apps.plugin"

apps.plugin is performing a hard-coded function of data collection for all
running processes. It cannot be instructed from the netdata daemon to perform
any task, so it is pretty safe to do this.

SETUID_WARNING
fi

# -----------------------------------------------------------------------------
# Keep un-install info

cat >netdata-uninstaller.sh <<UNINSTALL
#!/usr/bin/env bash

# this script will uninstall netdata

if [ "\$1" != "--force" ]
    then
    echo >&2 "This script will REMOVE netdata from your system."
    echo >&2 "Run it again with --force to do it."
    exit 1
fi

echo >&2 "Stopping a possibly running netdata..."
for p in \$(pidof netdata); do kill \$p; done
sleep 2

deletedir() {
    if [ ! -z "\$1" -a -d "\$1" ]
        then
        echo
        echo "Deleting directory '\$1' ..."
        rm -I -R "\$1"
    fi
}

if [ ! -z "${NETDATA_PREFIX}" -a -d "${NETDATA_PREFIX}" ]
    then
    # installation prefix was given

    deletedir "${NETDATA_PREFIX}"

else
    # installation prefix was NOT given

    if [ -f "${NETDATA_PREFIX}/usr/sbin/netdata" ]
        then
        echo "Deleting ${NETDATA_PREFIX}/usr/sbin/netdata ..."
        rm -i "${NETDATA_PREFIX}/usr/sbin/netdata"
    fi

    deletedir "${NETDATA_PREFIX}/etc/netdata"
    deletedir "${NETDATA_PREFIX}/usr/share/netdata"
    deletedir "${NETDATA_PREFIX}/usr/libexec/netdata"
    deletedir "${NETDATA_PREFIX}/var/lib/netdata"
    deletedir "${NETDATA_PREFIX}/var/cache/netdata"
    deletedir "${NETDATA_PREFIX}/var/log/netdata"
fi

if [ -f /etc/logrotate.d/netdata ]
    then
    echo "Deleting /etc/logrotate.d/netdata ..."
    rm -i /etc/logrotate.d/netdata
fi

if [ -f /etc/systemd/system/netdata.service ]
    then
    echo "Deleting /etc/systemd/system/netdata.service ..."
    rm -i /etc/systemd/system/netdata.service
fi

getent passwd netdata > /dev/null
if [ $? -eq 0 ]
    then
    echo
    echo "You may also want to remove the user netdata"
    echo "by running:"
    echo "   userdel netdata"
fi

getent group netdata > /dev/null
if [ $? -eq 0 ]
    then
    echo
    echo "You may also want to remove the group netdata"
    echo "by running:"
    echo "   groupdel netdata"
fi

getent group docker > /dev/null
if [ $? -eq 0 -a "${NETDATA_ADDED_TO_DOCKER}" = "1" ]
    then
    echo
    echo "You may also want to remove the netdata user from the docker group"
    echo "by running:"
    echo "   gpasswd -d netdata docker"
fi

UNINSTALL
chmod 750 netdata-uninstaller.sh

# -----------------------------------------------------------------------------

cat <<END


-------------------------------------------------------------------------------

OK. NetData is installed and it is running.

-------------------------------------------------------------------------------

By default netdata listens on all IPs on port ${NETDATA_PORT},
so you can access it with:

http://this.machine.ip:${NETDATA_PORT}/

To stop netdata, just kill it, with:

  killall netdata

To start it, just run it:

  ${NETDATA_PREFIX}/usr/sbin/netdata


END
echo >&2 "Uninstall script generated: ./netdata-uninstaller.sh"

if [ -d .git ]
    then
    cat >netdata-updater.sh.new <<REINSTALL
#!/usr/bin/env bash

force=0
[ "\${1}" = "-f" ] && force=1

export PATH="\${PATH}:${PATH}"
export CFLAGS="${CFLAGS}"

INSTALL_UID="${UID}"
if [ "\${INSTALL_UID}" != "\${UID}" ]
    then
    echo >&2 "This script should be run as user with uid \${INSTALL_UID} but it now runs with uid \${UID}"
    exit 1
fi

# make sure we cd to the working directory
cd "${REINSTALL_PWD}" || exit 1

# make sure there is .git here
[ \${force} -eq 0 -a ! -d .git ] && echo >&2 "No git structures found at: ${REINSTALL_PWD} (use -f for force re-install)" && exit 1

# signal netdata to start saving its database
# this is handy if your database is big
pids=\$(pidof netdata)
[ ! -z "\${pids}" ] && kill -USR1 \${pids}

tmp=
if [ -t 2 ]
    then
    # we are running on a terminal
    # open fd 3 and send it to stderr
    exec 3>&2
else
    # we are headless
    # create a temporary file for the log
    tmp=\$(mktemp /tmp/netdata-updater-log-XXXXXX.log)
    # open fd 3 and send it to tmp
    exec 3>\${tmp}
fi

info() {
    echo >&3 "\$(date) : INFO: " "\${@}"
}

emptyline() {
    echo >&3
}

error() {
    echo >&3 "\$(date) : ERROR: " "\${@}"
}

# this is what we will do if it fails (head-less only)
failed() {
    error "FAILED TO UPDATE NETDATA : \${1}"

    if [ ! -z "\${tmp}" ]
    then
        cat >&2 "\${tmp}"
        rm "\${tmp}"
    fi
    exit 1
}

get_latest_commit_id() {
    git log -1           2>&3 |\\
        grep ^commit     2>&3 |\\
        head -n 1        2>&3 |\\
        cut -d ' ' -f 2  2>&3
}

update() {
    [ -z "\${tmp}" ] && info "Running on a terminal - (this script also supports running headless from crontab)"

    emptyline

    if [ -d .git ]
        then
        info "Updating netdata source from github..."

        last_commit="\$(get_latest_commit_id)"
        [ \${force} -eq 0 -a -z "\${last_commit}" ] && failed "CANNOT GET LAST COMMIT ID (use -f for force re-install)"

        git pull >&3 2>&3 || failed "CANNOT FETCH LATEST SOURCE (use -f for force re-install)"

        new_commit="\$(get_latest_commit_id)"
        if [ \${force} -eq 0 ]
            then
            [ -z "\${new_commit}" ] && failed "CANNOT GET NEW LAST COMMIT ID (use -f for force re-install)"
            [ "\${new_commit}" = "\${last_commit}" ] && info "Nothing to be done! (use -f to force re-install)" && exit 0
        fi
    elif [ \${force} -eq 0 ]
        then
        failed "CANNOT FIND GIT STRUCTURES IN \$(pwd) (use -f for force re-install)"
    fi

    emptyline
    info "Re-installing netdata..."
    ${REINSTALL_COMMAND// --dont-wait/} --dont-wait >&3 2>&3 || failed "FAILED TO COMPILE/INSTALL NETDATA"

    [ ! -z "\${tmp}" ] && rm "\${tmp}" && tmp=
    return 0
}

# the installer updates this script - so we run and exit in a single line
update && exit 0
###############################################################################
###############################################################################
REINSTALL
    chmod 755 netdata-updater.sh.new
    mv -f netdata-updater.sh.new netdata-updater.sh
    echo >&2 "Update script generated   : ./netdata-updater.sh"
elif [ -f "netdata-updater.sh" ]
    then
    rm "netdata-updater.sh"
fi

banner "is installed and running now!"
echo >&2 "  enjoy real-time performance and health monitoring..."
echo >&2 
exit 0