#!/bin/bash

# declare the variables required for this script
function declareVars() {

  # this group will be created for docker
  group_to_add=docker

  # this is the url for the blockchain archive
  blockchain_7zip_url="https://archive.metervalidatorbot.com/archive"

  # if this flag is true we will download  the chain to bootstrap the node installation
  download_chain_flag='false'

  # regenerate the public
  regenerate_public_key='false'

  # if this flag is true we will force remove any related containers that the end user may have attempted to install
  # themselves
  force_removal_flag='false'

  # if this flag is true we will download and install the watchtower container
  watchtower_install_flag='false'

  # force Y response to all messages
  assume_yes='false'

  # yes and no options accepted at keyboard prompts
  yes_option="y"
  no_option="n"

  install_directory="$HOME/meter_main_data"

  # mega installer package - blank by default
  mega_installer_package=''

  # by default we will remove the mega application after the script has finished executing
  remove_mega_after_archive_download='true'

}

# outputAscii outputs the ascii text
function outputAscii() {

    echo "MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMWMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
0000000000000000|0xffbeddcaa68dc953ee4f3d040ab83cb0ac65498b|000000000000000
MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMWMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
MMMMMMMMMMMMMMMMMMMMMMMMMWNXKOkxdoollllooddxO0XNWMMMMMMMMMMMMMMMMMMMMMMMMMM
MMMMMMMMMMMMMMMMMMMMMWXOdl:,'.................,;cox0XWMMMMMMMMMMMMMMMMMMMMM
MMMMMMMMMMMMMMMMMWN0dc,.............................,cx0NMMMMMMMMMMMMMMMMMM
MMMMMMMMMMMMMMMN0d:'.......';:lodxxkkkkkxxdol:,'.......':d0NMMMMMMMMMMMMMMM
MMMMMMMMMMMMWNkc'......':ok0XWWMMMMMMMMMMMMMWWX0xo:'......'ckXMMMMMMMMMMMMM
MMMMMMMMMMMNk:......,lxKNWMMMMMMMMMMMMMMMMMMMMMMMWN0xc'......:kNMMMMMMMMMMM
MMMMMMMMMW0c......:xKWMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMN0o;.....'c0WMMMMMMMMM
MMMMMMMMXd,.....:kXMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMWXx;.....,xNMMMMMMMM
MMMMMMMKl.....,dXMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMWXd,....'oXMMMMMMM
MMMMMMKc.....c0WMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMWO:.....lXMMMMMM
MMMMMXl.....lKMMMMMMMMMMMMMMMMNKXMMMMMMMMMMMMMMMWXKNMMMMMMMMWKc....;xNMMMMM
MMMMNd'....lXMMMMMMMMMMMMMMWKx:c0MMMMMMMMMMMWN0xl,c0MMMMMMMMMWXxdxOKNWMMWWW
MMMWO,....:0MMMMMMMMMMMMMNOo,..cKMMMMMMMMWXOo:'...lXMMMMMMMMMMMMMWWXKOO0KNW
MMMXl....'xWMMMMMMMMMMWXxc'....oNMMMWWN0xc,.......oNMMMMMMMWNX0kdolodkKNWMM
MMM0;....cKMMMMMMMMMN0o;......'kWNKkoc;'.........'xWMWNKOxol:,',cdOXWMWWMMM
MMWk,....oNMMMMMMWXkc'........'ldc,........'.....'ldoc;'...';okKWMWX0do0MMM
MMWx'....xWMMMMN0o;....................':dkl'...........;lx0NWMMW0l;'.'xWMM
MMWx'..'lKMMWXkc'.....,:;..........;loxKNWKc........,:dOXWMMMMMMNo....'xWMM
MMMk;;d0WMWKd;....,cdOXKc......':oOXWMMMMWx'....';okKNMMMMMMMMMMXl....'kMMM
MMMX0XWWNOl,..,cdOXWMMM0;...,cx0NWMMMMMMMKc..,cx0NWMMMMMMMMMMMMMK:....;0MMM
MMMMMWKx:,;cdOXWMMMMMMWx;;okXWMMMMMMMMMMWOodOXWMMMMMMMMMMMMMMMMWk'....oNMMM
MMMNOdcldOXWMMMMMMMMMMWK0NWMMMMMMMMMMMMMWNWMMMMMMMMMMMMMMMMMMMM0:....,OWMMM
WN0kkOXWMWNKNMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMKc.....oNMMMM
NXXWMMWKxl;,lXMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMKl.....cKMMMMM
MMMMMMXo.....c0WMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMW0c.....cKMMMMMM
MMMMMMWKl.....,dXWMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMXx;.....lKMMMMMMM
MMMMMMMMXd,.....:kNMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMNk:.....,dXMMMMMMMM
MMMMMMMMMW0c......:xXWMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMWKx:......cOWMMMMMMMMM
MMMMMMMMMMMNk:......,okXWMMMMMMMMMMMMMMMMMMMMMMMMMWXkl,......:kNMMMMMMMMMMM
MMMMMMMMMMMMMNkc'......,cdkKNWMMMMMMMMMMMMMMMWNKOdc,......'ckXWMMMMMMMMMMMM
MMMMMMMMMMMMMMMN0o;........';codxkkOOOOOOkxdoc;'........;o0NMMMMMMMMMMMMMMM
MMMMMMMMMMMMMMMMMWXOd:'.............................,cdOXWMMMMMMMMMMMMMMMMM
MMMMMMMMMMMMMMMMMMMMMNKkdc;,..................',:ldOXWMMMMMMMMMMMMMMMMMMMMM
MMMMMMMMMMMMMMMMMMMMMMMMMWNK0Oxdooolooolooodxk0XNWMMMMMMMMMMMMMMMMMMMMMMMMM
MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
0000000000000000|0xffbeddcaa68dc953ee4f3d040ab83cb0ac65498b|000000000000000"

}


# this function will return true if the application passed into it exists on the system
function isInstalled()
{
  command -v "$1" >/dev/null 2>&1
}


# this function outputs the help text / manual for the -h output
function outputHelpText() {

  echo "Below are the possible options to use this tool."
  echo "-d will download the chain before your node boots. It speeds up the process considerably."
  echo "-f will force remove any existing docker images if you have attempted to install/run them before."
  echo "-w will download and install watchtower."
  echo "-h will show this prompt."
  echo -e "\nPlease note that the options can be chained ie -dfw will chain the above options."

  exit

}

# outputs the exit message
function exitMessage() {

  outputAscii

  echo "~~~~~ Don't forget to open your ports!!"
  if [ "$watchtower_install_flag" == 'false' ]; then
      echo "~~~~~ You opted not to install Watchtower. Please note this means that you must install updates yourself. Watchtower is advised."
  fi
  echo "~~~~~ Please consider making a MTR/MTRG donation if this script helped you [ 0xffbeddcaa68dc953ee4f3d040ab83cb0ac65498b ]. It would really help with the hosting costs. Thanks!"
}

installMegaIfRequired() {

  if isInstalled mega-version; then

    # we dont want to remove mega if it already existed before executing this script
    remove_mega_after_archive_download='false'

    return 1

  elif test -r "/etc/os-release"; then

    # source the os-release file
	  . /etc/os-release

		# todo - allow the end user to pass in a defined debian package URL to use

    if [ "$VERSION_CODENAME" == "bionic" ]; then
      # 18.04
      deb="https://mega.nz/linux/MEGAsync/xUbuntu_18.04/amd64/megacmd_1.5.1-1.1_amd64.deb"
    elif [ "$VERSION_CODENAME" == "focal" ]; then
      # 20.04
      deb="https://mega.nz/linux/MEGAsync/xUbuntu_20.04/amd64/megacmd_1.5.1-1.1_amd64.deb"
    elif [ "$VERSION_CODENAME" == "bullseye" ]; then
      deb="https://mega.nz/linux/MEGAsync/Debian_11/amd64/megacmd_1.5.1-1.1_amd64.deb"
    elif [ "$VERSION_CODENAME" == "buster" ]; then
      deb="https://mega.nz/linux/MEGAsync/Debian_10.0/amd64/megacmd_1.5.1-1.1_amd64.deb"
    else
      return 0
    fi

	else
	  return 0
	fi

  # download the package
	wget -O ~/mega_debian_package.deb $deb

	# attempt to install the package
	# DEBIAN_FRONTEND=noninteractive will accept the defaults for any menu prompts
	sudo DEBIAN_FRONTEND=noninteractive apt install ~/mega_debian_package.deb -y

	# remove the installer
	rm ~/mega_debian_package.deb

	# required for Mega to start correctly
	sudo ldconfig

}

# downloads the 7z archive that contains the blockchain data
function bootstrapChain() {

  echo "~~~~~Give the container a minute to boot up... Please wait for 60 seconds"
  sleep 1m

  echo "Lets see if the folders have been created"
  paths=($(find . -name "instance-*"))

  printf "%s\n" "${paths[@]}"
  node_dir=$paths

  cd $node_dir

  echo "~~~~~Changed directory to $PWD"

  # get the container id
  docker_container_id="$(< /tmp/meter_node_cont_id.txt)"

  echo "~~~~~Now we will stop the container id:"
  docker kill $docker_container_id

  echo "~~~~~While the blockchain is downloading, you could spend the time opening ports following point 2(e) of this guide here:  https://paolo-g.medium.com/step-by-step-guide-to-creating-a-node-in-meter-mainnet-4cdde1085fbb"

  echo "~~~~~Lets download the blockchain data to bootstrap the syncing process"

  # assume we won't use mega for the download
  use_mega_link_for_download='false'

  # install the Mega application - it will be removed if not already installed on the system after the archive is downloaded
  installMegaIfRequired

  # check if Mega is usable
  if isInstalled mega-version; then

    # get the url for the latest archive
    megaLink=$(wget -q -O - https://archive.metervalidatorbot.com/archive-mega-link)

    # make sure we got a response value
    if [ megaLink ]; then

      echo "Mega Link fetched successfully: [$megaLink]"
      echo "We will use Mega to download the mirror - which is much faster"
      use_mega_link_for_download='true'
    fi
  fi

  # check if the we can use Mega (if any of the vars below are empty)
  if [[ -z $use_mega_link_for_download || -z $megaLink ]]; then

    echo "Issue occurred trying to use Mega. Falling back to server mirror for download:"

    # fall back to the slower mirror
    downloadStatus=$(downloadArchiveViaWget)

    if [ "$downloadStatus" -ne 0 ]; then
      echo "Failed to download the archive. Please try again."
      exit
    fi

  else

    echo "Mega application may take a second to start before the download starts...."
    echo "Please wait..."

    # trigger the download
    sudo mega-get $megaLink instance.7z

    # remove the mega application if it was installed by the script
    # we do this here instead of above the isInstalled check because the installation may have been attempted, but failed.
    if $remove_mega_after_archive_download; then
      echo "Removing the Mega application now that the archive is downloaded..."
      sudo apt remove -f -y megacmd
    fi

  fi


  echo "~~~~~Please wait - now unpacking the data"

  sudo 7z x instance.7z -aoa

  echo "~~~~~Deleting the 7z archive now that is is unpacked"

  sudo rm instance.7z

  docker start meter_main

  rm /tmp/meter_node_cont_id.txt
}

# function to download the archive via wget and handle any timeouts
function downloadArchiveViaWget() {

  local attempt=0
  local max_attempts=100
  local archive_download_complete=false

  while [[ $archive_download_complete == false && "$attempt" -le "$max_attempts" ]]
  do
    attempt=$(( $attempt + 1 ))
    sudo wget --continue --tries=0 -O instance.7z $blockchain_7zip_url -q --show-progress
    if [ $? -eq 0 ]; then
      archive_download_complete=true
    elif [ "$attempt" -lt "$max_attempts" ]; then
      echo -e "~~~~~Intermittent issue occurred whilst downloading archive... please wait..." >&2
      sleep 30s
    fi
  done

  # return a value based on the above status
  if [ $archive_download_complete == true ]; then
    echo 0
  else
    echo 1
  fi

}

# the main function
function main() {
  local flag

  # output the ASCII art
  outputAscii

  declareVars

  # this string contains the text that will output to the end user before they confirm their choices (if y is not set)
  message_for_output=""
  while getopts 'dfwhpyi:m:' flag; do
    case "${flag}" in
      h)
        outputHelpText
        ;;

      d)
        # lets make sure that the mirror is actually available before setting the flag
        if wget --spider $blockchain_7zip_url 2>/dev/null; then
          # it looks like the mirror is UP
          message_for_output="${message_for_output} ~opted to download the blockchain directly to speed up the syncing process\n"
          download_chain_flag='true'
        else
          # looks like like the mirror is DOWN
          message_for_output="${message_for_output} ~IMPORTANT:: You opted to download the blockchain directly, but sadly it appears the mirror is down. The script will still setup your node for you but it will have to sync as normal.\n"
          download_chain_flag='false'
        fi
        ;;

      f)
        message_for_output="${message_for_output} ~opted to force remove any container that has already been installed with the name meter_main\n"
        force_removal_flag='true'
      ;;

      p)
        message_for_output="${message_for_output} ~opted to regenerate the public key\n"
        regenerate_public_key='true'
      ;;

      y)
        message_for_output="${message_for_output} ~opted to accept all messages automatically\n"
        assume_yes='true'
      ;;

      w) message_for_output="${message_for_output} ~opted to install watchtower that will manage updates for you\n"
        watchtower_install_flag='true'
      ;;

      i)
        install_directory=${OPTARG}
      ;;

      m)
        message_for_output="${message_for_output} ~requested to use ${OPTARG} as the mega installer package\n"
        mega_installer_package=${OPTARG}
      ;;
    esac
  done

  echo "@This script is provided as is without any warranty."
  echo "@You are welcome to view the source of this script before executing."
  echo "@Feel free to contribute"
  echo "@If you have any interest in providing a mirror, please get in touch"
  echo "@Twitter - https://twitter.com/DaveDeWire "

  echo "@You may need to enter your sudo password during execution."
  echo "@Please reach out in the Meter Validators Telegram group if you have any issues"
  echo "https://t.me/Meter_IO"

  echo "@Please confirm; you have:"

  echo -e "${message_for_output}"

  if [ "$assume_yes" == 'false' ]; then
    mainmenuinput=""
    echo Enter Y to continue:
    while [[ ( $(echo ${mainmenuinput,,} | xargs) != ${yes_option} && $(echo ${mainmenuinput,,} | xargs) != ${no_option} ) ]]; do
      read -n 1 mainmenuinput
    done

    if [ ${mainmenuinput,,} = ${yes_option} ]; then
        echo -e "\n~BEGINNING"
    else
      echo -e "\nDid not confirm. Exiting"
      exit
    fi
  fi

  #groups
  if grep -q $group_to_add /etc/group
  then
    echo "~~~~~group exists already. Not creating"
  else
    echo "~~~~~Group does not exist. Creating Now."
    sudo groupadd $group_to_add
    echo "~~~~~Group $group_to_add created"
  fi

  if groups $USER | grep -q $group_to_add
  then
    echo "~~~~~{$USER} is in group already. No need to re-add"
  else
    echo "~~~~~{$USER} Not in group yet adding now"
    sudo usermod -aG $group_to_add $USER
    echo "~~~~~{$USER} added to group {$group_to_add}"
    echo "~When a user is added to a new group, the user must logout and log back in"
    echo "~Because this script is designed to be run directly from GitHub, the safest"
    echo "~way to do that is to restart the machine. When the machine reboots simply rerun the same command."
    echo "~Are you happy to restart now??"

    if [ "$assume_yes" == 'false' ]; then
      restartconfirmation=""
      echo Enter Y to continue:
      while [[ ( $(echo ${restartconfirmation,,} | xargs) != ${yes_option} && $(echo ${restartconfirmation,,} | xargs) != ${no_option} ) ]]; do
        read -n 1 restartconfirmation
      done
    else
      restartconfirmation="y"
    fi

    if [ ${restartconfirmation,,} = ${yes_option} ]; then
      echo -e "\n~~~~~Restarting now"
      sudo reboot now
      exit
    else
      echo -e "\n~~~~~Did not confirm. You will get unexpected results if you re-run without reloading your groups correctly! Exiting"
      exit
    fi

  fi

  echo "~~~~~Creating the install folder (if required)"
  mkdir -p "$install_directory"

  cd "$install_directory"

  echo "~~~~~Setting the METER_MAIN_DATA_PATH variable in ~/.bashrc"

  #unset in case it has been set previously
  unset METER_MAIN_DATA_PATH

  #set METER_MAIN_DATA_PATH variable
  source <(grep -m 1 "METER_MAIN_DATA_PATH" ~/.bashrc )

  #check if variable exists
  if [ ! -d "$install_directory" ]; then
    echo -e "~~~~~ERROR~~~~~"
    echo -e "~~~~~The path provided $install_directory is not valid or could not be created"
    echo -e "~~~~~Please check permissions or choose a different directory"
    exit
  elif [ -z "$METER_MAIN_DATA_PATH" ]; then
    echo "$METER_MAIN_DATA_PATH Variable doesnt exist, setting in bashrc"
    echo export "METER_MAIN_DATA_PATH=$PWD" >> ~/.bashrc
    source <(grep -m 1 "METER_MAIN_DATA_PATH" ~/.bashrc )
  elif [ "$METER_MAIN_DATA_PATH" != "$PWD" ]; then

    echo -e "~~~~~ERROR~~~~~"
    echo -e "$PWD"
    echo -e "~~~~~The METER_MAIN_DATA_PATH variable already exists in ~/.bashrc - but contains the wrong value"
    echo -e "~~~~~This variable is used to store the location of the data that is required to run a node so that it can be filtered through to docker."
    echo -e "~~~~~Please edit ~/.bashrc with a text editor and remove the line:"
    echo -e "export METER_MAIN_DATA_PATH=$METER_MAIN_DATA_PATH"
    unset METER_MAIN_DATA_PATH
    exit
  fi


  echo "~~~~~Path variable set to:"
  echo $METER_MAIN_DATA_PATH

  echo "~~~~~Lets install docker.io and 7zip"
  sudo apt update -y
  sudo apt install sudo docker.io p7zip-full -y

  # if -f is passed in, we will force remove
  if [ "$force_removal_flag" == 'true' ]; then
    # remove container id file if exists
    if [ -f "/tmp/meter_node_cont_id.txt" ]; then
      echo "~~~~~removing container id file";
      rm /tmp/meter_node_cont_id.txt
    fi

    if [ "$watchtower_install_flag" == 'true' ]; then
      echo "~~~~~Attempting to remove any previous references to Watchtower"
      docker container rm watchtower -f
    fi

    # remove the container
    docker container rm meter_main -f
  fi

  if [ "$download_chain_flag" == 'true' ]; then
    docker run --cidfile /tmp/meter_node_cont_id.txt --network host --name meter_main --restart always -e NETWORK="main" -v $METER_MAIN_DATA_PATH:/pos -d meterio/mainnet:latest
    bootstrapChain
  else
    echo -e "~~~~~Starting meter_main docker container"
    docker run --network host --name meter_main --restart always -e NETWORK="main" -v $METER_MAIN_DATA_PATH:/pos -d meterio/mainnet:latest
  fi

  # delete the public key if requested - it will be regenerated on boot
  if [ "$regenerate_public_key" == 'true' ]; then
    rm -f "$install_directory"/public.key
    echo -e "~~~~~Restarting meter_main after deleting old public key..."
    docker container restart meter_main
  fi

  if [ "$watchtower_install_flag" == 'true' ]; then
    echo -e "~~~~~Installing Watchtower"
    docker run -d --name watchtower --restart always -v /var/run/docker.sock:/var/run/docker.sock containrrr/watchtower --include-stopped --revive-stopped --enable-lifecycle-hooks --interval 10 --cleanup meter_main
  fi

  #output the private key if we can see it
  if [ -f "$PWD/public.key" ]; then
    echo "~~~~~Here is your public key. You can copy it from here, but make sure when you are setting up the node in the
    wallet that you do not have any whitespaces between the strings - it should all be on one line."
    cat public.key
  fi

  exitMessage
}

# trigger the main function
main "$@"