#!/bin/sh
set -e

nightwatch_config_dir='/etc/fastcomet/nightwatch.d/'

echoerr() { echo "$@" 1>&2; }

_fake_curl() {
	_input_url=$1
	PERL_LWP_SSL_VERIFY_HOSTNAME=0 perl -MLWP::UserAgent -e '$ua=LWP::UserAgent->new(); print $ua->get("$ARGV[0]")->decoded_content;' "$1"
	return 0
}

_check_apache_url() {
	_apache_url=$1
	_fake_curl "$_apache_url" | grep -q 'Scoreboard:'
	return $?
}

_check_nginx_url() {
	_nginx_url=$1
	_fake_curl "$_nginx_url" | grep -q 'server accepts handled requests'
	return $?
}

_write_option(){
	_write_file=$1
	_checked_directive=$2
	_value=$3
	if egrep "^\s*$_checked_directive[[:space:]]+\S+" $_write_file >/dev/null; then
		sed -i "s|^\s*$_checked_directive.*|$_checked_directive $_value|g" $_write_file
	else
		if ! tail -c1 $_write_file | grep '^$' >/dev/null; then
			echo "" >> $_write_file
		fi
		echo "$_checked_directive $_value" >> $_write_file
	fi
}

apache_install() {
	apache_config_filename=${nightwatch_config_dir}Apache.conf

	db_get Nightwatch/apache-location
	location="$RET"

	if [ ! -z "$location" ]; then
		_write_option $apache_config_filename location "$location"
		apache_url="$location"
	else
		apache_url='http://127.0.0.1/server-status?auto'
	fi

	db_fset Nightwatch/apache-try-configure seen "false"
	db_get Nightwatch/apache-try-configure
	if [ "$RET" != "true" ]; then
		return 0
	fi
	db_set Nightwatch/apache-try-configure "false"

	# check for mod_status
	if [ ! -e /etc/apache2/mods-enabled/status.conf ]; then
		if ! a2enmod status;  then
			echoerr "Unable to enable mod_status for Apache. Please see https://library.linode.com/nightwatch/nightwatch-for-apache#sph_manual-configuration-all-distributions for instructions on configuring Apache to work with Nightwatch"
			return 1
		fi
	else
		pre_existing_status="true"
	fi

	cat >> /etc/apache2/mods-enabled/status.conf <<END
<IfModule mod_status.c>
ExtendedStatus On
<Location /server-status>
	SetHandler server-status
	Order deny,allow
	Deny from all
	Allow from 127.0.0.1
</Location>
</IfModule>
END

	apache_url_https=`echo $apache_url | sed 's/^http/https/'`
	if /etc/init.d/apache2 reload; then
		if _check_apache_url $apache_url; then
			_write_option $apache_config_filename location "$apache_url"
			echoerr "Apache mod_status enabled"
			return 0
		elif _check_apache_url $apache_url_https; then
			_write_option $apache_config_filename location "$apache_url_https"
			return 0;
		fi
	fi

	echoerr "Enabling mod_status for Apache failed. Rolling back changes"
	if [ -z "$pre_existing_status" ]; then
		a2dismod status
	fi
	head -n -9 /etc/apache2/mods-available/status.conf | tee /etc/apache2/mods-available/status.conf > /dev/null
	/etc/init.d/apache2 reload
	echoerr "Please see https://library.linode.com/nightwatch/nightwatch-for-apache#sph_manual-configuration-all-distributions for instructions on configuring Apache to work with Nightwatch. Auto-configuration failed"
}

nginx_install() {
	nginx_config_filename=${nightwatch_config_dir}Nginx.conf

	db_get Nightwatch/nginx-location
	location="$RET"

	if [ ! -z "$location" ]; then
		_write_option $nginx_config_filename location "$location"
		return 0
	fi

	db_fset Nightwatch/nginx-try-configure seen "false"
	db_get Nightwatch/nginx-try-configure
	if [ "$RET" != "true" ]; then
		return 0
	fi
	db_set Nightwatch/nginx-try-configure "false"

	cat >> /etc/nginx/sites-available/nightwatch <<END
server {
	listen 127.0.0.2:80;
	server_name 127.0.0.2;

	location /nginx_status {
		stub_status on;
		allow 127.0.0.1;
		deny all;
	}
}
END

	ln -s /etc/nginx/sites-available/nightwatch /etc/nginx/sites-enabled/
	if [ -h /etc/nginx/sites-enabled/nightwatch ]; then
		if /etc/init.d/nginx restart; then
			if _check_nginx_url http://127.0.0.2/nginx_status; then
				echoerr "Finished configuring nginx, writing new configuration to $nginx_config_filename"
				_write_option $nginx_config_filename location "http://127.0.0.2/nginx_status"
				return 0
			fi
		fi
	fi
	echoerr "Enabling stub_status failed. Rolling back changes"
	rm /etc/nginx/sites-enabled/nightwatch /etc/nginx/sites-available/nightwatch
	/etc/init.d/nginx restart
	echoerr "Please see https://library.linode.com/nightwatch/nightwatch-for-nginx#sph_manual-configuration-all-distributions for instructions on configuring nginx to work with Nightwatch. Auto-configuration failed"
}

mysql_install() {
	mysql_config_filename=${nightwatch_config_dir}MySQL.conf

	db_get Nightwatch/mysql-overwrite-creds
	overwrite="$RET"
	db_fset Nightwatch/mysql-create-creds seen "false"
	db_set Nightwatch/mysql-overwrite-creds "false"
	if [ "$overwrite" = "true" ]; then
		sed -i 's/^\s*\(username.*\)/#\1/g' $mysql_config_filename
		sed -i 's/^\s*\(password.*\)/#\1/g' $mysql_config_filename
		return 0
	fi

	db_get Nightwatch/mysql-password
	pass="$RET"

	if [ ! -z "$pass" ]; then
		_write_option $mysql_config_filename username "fastcomet-nightwatch"
		_write_option $mysql_config_filename password "$pass"
		db_set Nightwatch/mysql-password ""
		return 0
	fi
}

. /usr/share/debconf/confmodule
if [ ! -e /etc/fastcomet/nightwatch.key ]; then
	db_get Nightwatch/APIKey
	echo "$RET" > /etc/fastcomet/nightwatch.key
fi

apache_install
nginx_install
mysql_install
chmod -R o-rwx $nightwatch_config_dir
db_stop

if invoke-rc.d nightwatch status 1>/dev/null 2>&1; then
	invoke-rc.d nightwatch restart || true
else
	invoke-rc.d nightwatch start || true
fi

update-rc.d nightwatch defaults