#!/bin/bash

netdata=$(which netdata)

if [ -z "${netdata}" -o ! -f src/netdata ]
then
        echo >&2 "Running ./autogen.sh ..."
        ./autogen.sh || exit 1

        echo >&2 "Running ./configure ..."
        ./configure --prefix=/usr --sysconfdir=/etc --localstatedir=/var --with-zlib --with-math --with-user=netdata CFLAGS="-march=native -O3 -Wall -Wextra" || exit 1

        echo >&2 "Cleaning a possibly old compilation ..."
        make clean || exit 1

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

if [ -z "${netdata}" -o src/netdata -nt "${netdata}" ]
then
        echo >&2 "Installing netdata ..."
        make install

        echo >&2 "Adding netdata group ..."
        getent group netdata > /dev/null || groupadd -r netdata

        echo >&2 "Adding netdata user ..."
        getent passwd netdata > /dev/null || useradd -r -g netdata -c netdata -s /sbin/nologin -d / netdata
fi

netdata=$(which netdata)

base="`dirname "$0"`"

if [ ! -d "${base}" ]
then
	echo >&2 "Cannot find my home directory '${base}'."
	exit 1
fi
cd "${base}" || exit 1


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

# create an empty config if it does not exist
[ ! -f conf.d/netdata.conf ] && touch conf.d/netdata.conf

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

	if [ -s "/etc/netdata/netdata.conf" ]
		then
		line="$( grep "^[[:space:]]*${key}[[:space:]]*=[[:space:]]*" "conf.d/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}" )"

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

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

# directories
NETDATA_CACHE_DIR="$( config_option "database directory" "/var/cache/netdata" )"
NETDATA_WEB_DIR="$( config_option "web files directory" "/usr/share/netdata/web" )"
NETDATA_LOG_DIR="log"
NETDATA_CONF_DIR="conf.d"


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

echo >&2 "Fixing directory permissions for user ${NETDATA_USER}..."
for x in "${NETDATA_WEB_DIR}" "${NETDATA_CONF_DIR}" "${NETDATA_CACHE_DIR}" "${NETDATA_LOG_DIR}"
do
	if [ ! -d "${x}" ]
		then
		mkdir "${x}" || exit 1
	fi
	chown -R "${NETDATA_USER}" "${x}" || echo >&2 "WARNING: Cannot change the ownership of the files in directory ${x} to ${NETDATA_USER}..."
	chmod 0775 "${x}" "${x}" || echo >&2 "WARNING: Cannot change the permissions of the directory ${x} to 0755..."
done

# fix apps.plugin to be setuid to root
chown root '/usr/libexec/netdata/plugins.d/apps.plugin' && chmod 4755 '/usr/libexec/netdata/plugins.d/apps.plugin'


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

printf >&2 "Stopping a (possibly) running netdata..."
ret=0
count=0
while [ $ret -eq 0 ]
do
	if [ $count -gt 15 ]
		then
		echo >&2 "Cannot stop the running netdata."
		exit 1
	fi

	count=$((count + 1))
	killall netdata 2>/dev/null
	ret=$?
	test $ret -eq 0 && printf >&2 "." && sleep 2
done
echo >&2


# -----------------------------------------------------------------------------
# run netdata

# avoid extended stat(/etc/localtime)
# http://stackoverflow.com/questions/4554271/how-to-avoid-excessive-stat-etc-localtime-calls-in-strftime-on-linux
export TZ=":/etc/localtime"

echo >&2 "Starting netdata..."
netdata "${@}"

if [ $? -ne 0 ]
	then
	echo >&2
	echo >&2 "SORRY! FAILED TO START NETDATA!"
	exit 1
else
	echo >&2 "OK. NetData Started!"
fi


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

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

	# remove a possibly obsolete download
	[ -f /etc/netdata/netdata.conf.new ] && rm /etc/netdata/netdata.conf.new

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

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

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

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

echo >&2
echo >&2 "Hit http://localhost:${NETDATA_PORT}/ from your browser."
echo >&2
echo >&2 "Enjoy..."
echo >&2