#!/bin/bash

seqDir="$( cd "$( dirname "${BASH_SOURCE[0]}" )" >>/dev/null 2>&1 && pwd )"
toolName="snmpd"
toolConfigLoc="/etc/snmp"
toolConfig="${toolConfigLoc}/snmpd.conf"


step_1_info() { echo "Install packages for $toolName"; }
step_1_alias() { ALIAS="install"; }
step_1() {
  exe apt update
  if [ $QUIET != 0 ]; then
    exe apt-get -qq install $toolName
  else
    exe apt install $toolName
  fi
  endReturn -o $? "$toolName installation failed"
}

step_2_info() { echo "Setup snmp v3 access"; }
step_2() {
  #
  ## Create authentication entry
  exep "cat \"$v3AuthLoc\" | grep -e '^\s*usmUser'"
  if [ "$?" == "0" ]; then
    echo

    exe read -p "User entry found. Continue: y/n(default)? " answer
    case $answer in
      [yY])
        echo
        echo Continuing installation...
        ;;
      *)
        echo
        echo Installation aborted
        return 1; 
        ;;
    esac 
  fi

  read -p "SNMPv3 Username: " v3User
  read -s -p "SNMPv3 Password: " v3Pass
  echo

  exe service snmpd stop

  # this line will be replaced on start of snmpd with a line starting with:
  # usmUser
  v3AuthEntry="createUser ${v3User} SHA \"${v3Pass}\" DES" 
  addConf -a "$v3AuthEntry" "$v3AuthLoc"

  #
  ## Add custom base configuration
  addConf -c "" "${toolConfig}"
  exe cp "${seqDir}/snmpd.conf" "${toolConfig}"

  #
  ## Add username as rouser
  exe sed -i "s/authOnlyUser/${v3User}/" "$toolConfig"

  #
  ## Write syslocation
  exe read -p "sysLocation: " v3Location
  exe read -p "sysContact (name <webmaster@example.com>): " v3Contact

  exe sed -i "s/\(sysLocation\s*\).*/\1${v3Location}/" "$toolConfig"
  exe sed -i "s/\(sysContact\s*\).*/\1${v3Contact}/" "$toolConfig"

  exe service snmpd start
}
v3AuthLoc="/var/lib/snmp/snmpd.conf"

step_20_info() { echo "Extend $toolName for Raspberry Pi"; }
step_20_alias() { ALIAS="raspberry"; }
step_20() {
  checkExtend raspberry
  if [ "$?" != "0" ]; then
    return 1
  fi

  exe wget https://raw.githubusercontent.com/librenms/librenms-agent/master/snmp/raspberry.sh -O "${rpiExtendLoc}"
  endReturn -o $? "Download failed"
  exe chmod +x "$rpiExtendLoc"

  addConf -a "extend raspberry /etc/snmp/raspberry.sh" "$toolConfig"
  addConf -c "$rpiSudoersContent" "$rpiSudoersLoc"

  exe service snmpd restart
}

rpiExtendLoc="${toolConfigLoc}/raspberry.sh"
rpiSudoersLoc="/etc/sudoers.d/snmprpi"
rpiSudoersContent="
Debian-snmp ALL=(ALL) NOPASSWD: /etc/snmp/raspberry.sh, /usr/bin/vcgencmd*"

step_22_info() { echo "Extend $toolName with OS update availablity"; }
step_22_alias() { ALIAS="osupdate"; }
step_22() {
  checkExtend osupdate 
  if [ "$?" != "0" ]; then
    return 1
  fi
  
  exe wget https://raw.githubusercontent.com/librenms/librenms-agent/master/snmp/osupdate -O "${osUpdateExtendLoc}"
  endReturn -o $? "Download failed"
  exe chmod +x "$osUpdateExtendLoc"
  addConf -a "extend osupdate $osUpdateExtendLoc" "$toolConfig"

  exe service snmpd restart
}
osUpdateExtendLoc="${toolConfigLoc}/osupdate"

step_23_info() { echo "Create cron job for periodical (every 8 hours) apt-get update"; }
step_23() {
  addConf -s "$osUpdateCronContent" "$osUpdateCron"
}
osUpdateCron="/etc/cron.d/aptUpdate"
osUpdateCronContent="22 */6 * * * root /usr/bin/apt-get -qq update"

step_25_info() { echo "Prepare nginx to provide php-fpm status to $toolName"; }
step_25_alias() { ALIAS="phpfpm"; }
step_25() {
  echo -e "\n [!] Please add the following to your default server:\n"
  echo "$phpFpmStatusNginx"
  echo
  if [ $QUIET -ne 0 ] ; then
    answer=n
  else
    exe read -p "Open new shell to configure y/[n]? " answer
  fi
  case $answer in
    [yY])
      echo " [I] Opening interactive shell. Type \"exit\" to return to this script."
      exe bash -i
      echo " [I] Interactive shell ended. Continuing with $0."
      exe nginx -t
      endReturn -o $? "Nginx configuration error"

      exe service nginx restart
      ;;
    *)
      ;;
  esac
}
phpVersionStr="$(php -r 'echo PHP_MAJOR_VERSION.".".PHP_MINOR_VERSION;')"
phpFpmStatusNginx="# Provide php-fpm status
location ~ ^/(status|ping)\$ {
access_log off;
allow 127.0.0.1;
allow ::1;
deny all;
include fastcgi_params;
fastcgi_param SCRIPT_FILENAME \$document_root\$fastcgi_script_name;
#fastcgi_pass 127.0.0.1:9000;
fastcgi_pass   unix:/var/run/php/php${phpVersionStr}-fpm.sock;
}"

step_26_info() { echo "Prepare php config for php-fpm status"; }
step_26_alias() { ALIAS="phpfpm_config"; }
step_26() {
  exe sed -i "s/^;\(pm\.status_path\)/\1/" "$phpPoolConfigLoc"
  exe php-fpm${phpVersionStr} -t
  endReturn -o $? "Invalid php configuration"

  service php${phpVersionStr}-fpm restart
}
phpConfigDir="/etc/php/${phpVersionStr}"
phpPoolConfigLoc="${phpConfigDir}/fpm/pool.d/www.conf"

step_27_info() { echo "Extend $toolName with parsing of php-fpm status"; }
step_27_alias() { ALIAS="phpfpm_extend"; }
step_27() {
  checkExtend phpfpmsp
  if [ "$?" != "0" ]; then
    return 1
  fi

  exe wget https://github.com/librenms/librenms-agent/raw/master/snmp/phpfpmsp -O "${phpfpmExtendLoc}"
  endReturn -o $? "Download failed"
  exe chmod +x "$phpfpmExtendLoc"

  addConf -a "extend phpfpmsp ${phpfpmExtendLoc}" "$toolConfig"

  exe service snmpd restart
}
phpfpmExtendLoc="${toolConfigLoc}/phpfpmsp"

step_29_info() { echo "Prepare nginx to provide status to $toolName"; }
step_29_alias() { ALIAS="nginx"; }
step_29() {
  echo -e "\n [!] Please add the following to your default server:\n"
  echo "$nginxStatus"
  echo
  if [ $QUIET -ne 0 ] ; then
    answer=n
  else
    exe read -p "Open new shell to configure y/[n]? " answer
  fi
  case $answer in
    [yY])
      echo " [I] Opening interactive shell. Type \"exit\" to return to this script."
      exe bash -i
      echo " [I] Interactive shell ended. Continuing with $0."
      exe nginx -t
      endReturn -o $? "Nginx configuration error"

      exe service nginx restart
      ;;
    *)
      ;;
  esac
}
nginxStatus="# Provide nginx status
location /nginx-status {
stub_status on;
access_log   off;
allow 127.0.0.1;
allow ::1;
deny all;
}
"
step_30_info() { echo "Extend $toolName with parsing of nginx status"; }
step_30_alias() { ALIAS="nginx_extend"; }
step_30() {
  checkExtend nginx
  if [ "$?" != "0" ]; then
    return 1
  fi

  exe wget https://raw.githubusercontent.com/librenms/librenms-agent/master/snmp/nginx -O "${nginxExtendLoc}"
  endReturn -o $? "Download failed"
  exe chmod +x "$nginxExtendLoc"

  addConf -a "extend nginx ${nginxExtendLoc}" "$toolConfig"

  exe service snmpd restart
}
nginxExtendLoc="${toolConfigLoc}/nginx"

#fail2ban
#exe wget https://github.com/librenms/librenms-agent/raw/master/snmp/fail2ban -O "${toolConfig}/fail2ban"

checkExtend() {
  # adding dry run output for clarification
  if [ "$DRY" != "0" ] ; then
    echo " [I] check if \"extend ${1}\" exists..dry-run"
  fi

  exep "cat \"$toolConfig\" | grep -e '^\s*extend\s\+${1}' >>/dev/null 2>&1"
  # Only warn if entry exists and dry-run is not seleted
  if [ "$?" == "0" ] && [ "$DRY" == "0" ] ; then  
    echoerr " [W] Extend for ${1} exists"
    return 1
  fi 
  
  return 0
}

VERSION_SEQREV=8
. sequencer.sh