#!/usr/bin/env bash

# Bash Strict Mode
set -euo pipefail
IFS='
'
cd -P "$(dirname "$0")"
PS4='-\D{%F %T} '

export DEBIAN_FRONTEND=noninteractive
export DEBIAN_PRIORITY=critical

# Fix Debian 10 bug (https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=905409)
PATH=/sbin:/usr/sbin:$PATH

function sysConfig() {
  echo "Enter the server FQDN $(tput setaf 2)[System: $(hostname)]$(tput sgr0):"
  read serverFQDN
  hostnamectl set-hostname $serverFQDN

  echo "Enter the server Time Zone $(tput setaf 2)[System: $(cat /etc/timezone)]$(tput sgr0): "
  read serverTZ
  timedatectl set-timezone $serverTZ

  # Navigate to tmp
  cd /tmp

  # Debian stable OS
  apt-get update
  apt-get -y -o "Dpkg::Options::=--force-confdef" -o "Dpkg::Options::=--force-confold" upgrade
  apt-get -y dist-upgrade

  # Disable OpenStack SSH malware
  mv /home/debian/.ssh/authorized_keys /root/.ssh/authorized_keys || :
  sed -i '/Generated-by-Nova/d' /root/.ssh/authorized_keys || :
  chown root:root /root/.ssh/authorized_keys || :

  # Terminal goodies
  touch .hushlogin

  cat <<'EOF' >>/root/.bashrc
export LS_OPTIONS="--color=auto"
eval "`dircolors`"

alias ctop="docker run --rm -it --name=ctop -v /var/run/docker.sock:/var/run/docker.sock:ro quay.io/vektorlab/ctop"
alias df="df --si"
alias du="du -cs --si"
alias free="free -h --si"
alias l="ls $LS_OPTIONS -al --si --group-directories-first"
alias less="less -i"
alias nano="nano -clDOST4"
alias pstree="pstree -palU"

export HISTCONTROL=ignoreboth
export HISTFILESIZE=
export HISTSIZE=
export HISTTIMEFORMAT="%F %T "
export DOCKER_BUILDKIT=1 COMPOSE_DOCKER_CLI_BUILD=1
EOF

  cat <<'EOF' >>/etc/inputrc
set completion-ignore-case
set show-all-if-ambiguous On
set show-all-if-unmodified On
EOF

  cat <<'EOF' >>/etc/bash.bashrc
if ! shopt -oq posix; then
  if [ -f /usr/share/bash-completion/bash_completion ]; then
    . /usr/share/bash-completion/bash_completion
  elif [ -f /etc/bash_completion ]; then
    . /etc/bash_completion
  fi
fi
EOF

  # Basic packages
  apt-get -y install man bash-completion git ufw jq curl build-essential netcat wget psmisc lz4 file net-tools brotli unzip zip moreutils dnsutils fail2ban xauth sysfsutils rsync iperf pv tree mc screen ssh iotop htop awscli whois sudo

  # Enable time synchronization
  timedatectl set-ntp true

  # Configure screen
  cat <<'EOF' >>/etc/screenrc
startup_message off
shell -$SHELL
defscrollback 100000
bind l eval clear "scrollback 0" "scrollback 100000"
EOF

  # Configure SSH
  cat <<'EOF' >>/etc/ssh/sshd_config
Port 521
PasswordAuthentication no
AllowUsers root
X11UseLocalhost no
EOF
  systemctl restart ssh

  touch /root/.Xauthority

  # Firewall
  ufw allow in 80/tcp
  ufw allow in 443/tcp
  ufw allow in 521/tcp
  ufw allow in 8080/tcp
  ufw allow in 8082/tcp
  ufw logging off
  ufw --force enable
  ufw --force delete 6
  ufw --force delete 6
  ufw --force delete 6
  ufw --force delete 6
  ufw --force delete 6

  # Optimize
  systemctl disable unattended-upgrades.service apt-daily.timer apt-daily-upgrade.timer console-setup.service keyboard-setup.service remote-fs.target man-db.timer systemd-timesyncd.service
  sed -i 's/MODULES=most/MODULES=dep/g' /etc/initramfs-tools/initramfs.conf
  sed -i 's/COMPRESS=gzip/COMPRESS=lz4/g' /etc/initramfs-tools/initramfs.conf
  echo 'RESUME=none' >>/etc/initramfs-tools/conf.d/resume
  update-initramfs -u
  echo 'GRUB_TIMEOUT=0' >>/etc/default/grub
  update-grub
  apt-get -y purge apparmor exim\*

  for i in $(seq 0 "$(nproc --ignore 1)"); do
    echo "devices/system/cpu/cpu${i}/cpufreq/scaling_governor = performance" >>/etc/sysfs.conf
  done

  # Disable sleep when closing laptop screen
  echo HandleLidSwitch=ignore >>/etc/systemd/logind.conf

  # noatime
  sed -i 's| / ext4 | / ext4 noatime,|g' /etc/fstab

  # Disable swap
  swapoff -a
  sed -i '/swap/d' /etc/fstab

  # Docker
  apt-get -y install apt-transport-https ca-certificates curl gnupg2 software-properties-common
  curl -fsSL https://download.docker.com/linux/debian/gpg | apt-key add -
  add-apt-repository "deb [arch=amd64] https://download.docker.com/linux/debian $(lsb_release -cs) stable"
  apt-get update
  apt-get -y install docker-ce docker-ce-cli containerd.io

  # Docker compose
  curl -L "https://github.com/docker/compose/releases/download/1.29.1/docker-compose-$(uname -s)-$(uname -m)" -o /usr/local/bin/docker-compose
  chmod +x /usr/local/bin/docker-compose
  curl -L https://raw.githubusercontent.com/docker/compose/1.29.1/contrib/completion/bash/docker-compose -o /etc/bash_completion.d/docker-compose

  # NodeJS
  curl -fsSL https://deb.nodesource.com/setup_18.x | bash && apt-get install -y nodejs

  # Git
  echo deb http://deb.debian.org/debian buster-backports main | tee /etc/apt/sources.list.d/buster-backports.list
  apt-get update && apt-get -y install -t buster-backports git

  # Generate SSH key
  ssh-keygen -ted25519 -f ~/.ssh/id_ed25519 -N ''

  # Use Cloudflare DNS server
  echo 'supersede domain-name-servers 1.1.1.1;' >>/etc/dhcp/dhclient.conf

  # Cleanup
  sed -i '/^deb-src/d' /etc/apt/sources.list
  apt-get update
  apt-get -y purge unattended-upgrades
  apt-get -y autoremove --purge
  apt-get clean

  # SSH Keys Infra Team
  curl https://github.com/{harryvasanth,frenchris,kigiri}.keys >>~/.ssh/authorized_keys

  # Create Core directories
  mkdir -p /root/core/scripts/misc

}

# Check Config
function checkConfig() {
  test "$(command -v "${1:-}")" && echo -n ✅ || echo -n ❌
  echo " $@"
}

# Check configs in the List
function checkList() {
  checkConfig docker-compose
  checkConfig docker
  checkConfig node
  checkConfig git
  checkConfig man
  checkConfig ufw
  checkConfig jq
  checkConfig curl
  checkConfig netcat
  checkConfig wget
  checkConfig lz4
  checkConfig file
  checkConfig brotli
  checkConfig unzip
  checkConfig zip
  checkConfig fail2ban-server
  checkConfig xauth
  checkConfig rsync
  checkConfig iperf
  checkConfig pv
  checkConfig tree
  checkConfig mc
  checkConfig screen
  checkConfig ssh
  checkConfig iotop
  checkConfig htop
  checkConfig aws
  checkConfig whois
  checkConfig sudo

  test "$(ls ~/.ssh/*.pub 2>/dev/null)" && echo -n ✅ || echo -n ❌
  echo " SSH private/public key pair generated"
}

function runHTTPS() {
  echo -e "Deploying HTTPS service: \n"
  echo "Enter the server FQDN $(tput setaf 2)[System: $(hostname)]$(tput sgr0):"
  read httpsFQDN
  # Check if the FQDN is valid
  if ping -c1 -W1 $httpsFQDN 2>/dev/null; then
    cd /root/core/https
    DOMAIN=$httpsFQDN ./run.sh
    echo -e "HTTPS service is up! \n"
  else
    echo "$(tput setaf 1)$(tput bold)The FQDN: $httpsFQDN is not reachable$(tput sgr0)"
    echo "$(tput setaf 1)Please check your DNS configuration$(tput sgr0)"
    runHTTPS
  fi
}

# Deploy core repositories
function deployCore() {
  # Check for the presence of configurations
  test "$(ls ~/.ssh/*.pub 2>/dev/null)" && echo -n "$(tput setaf 2)$(tput bold)Config check passed!$(tput sgr0)" || exit 1
  echo -e "$(tput setaf 6)$(tput bold)\nThe core components will be deployed to the server: $(tput sgr0)\n"

  # Clone core repositories
  git clone git@github.com:01-edu/runner.git /root/core/runner
  git clone git@github.com:01-edu/https.git /root/core/https

  # Docker login
  echo -e "Enter the docker username: "
  read dockerUsername
  echo -e "Enter the docker password: "
  read dockerPassword
  docker login docker.01-edu.org -u $dockerUsername -p $dockerPassword

  # Deploy HTTPS
  runHTTPS

  # Deploy Runner
  echo -e "Deploying Runner service: \n "
  cd /root/core/runner
  echo -e "Enter the runner Registry password: "
  read registryPassword
  REGISTRY_PASSWORD=$registryPassword ./run.sh
  echo -e "Runner service is up! \n"
}

function deployPlatform() {
  # Check for the presence of configurations
  test "$(ls ~/.ssh/*.pub 2>/dev/null)" && echo -n "$(tput setaf 2)$(tput bold)Config check passed!$(tput sgr0)" || exit 1
  echo -e "$(tput setaf 6)$(tput bold)\nThe platform components will be deployed to the server: $(tput sgr0)\n"

  # Clone platform repository
  echo "Enter the server FQDN $(tput setaf 2)[System: $(hostname)]$(tput sgr0):"
  read serverFQDN
  git clone git@github.com:01-edu/all.git /root/$serverFQDN
  cd /root/$serverFQDN
  # Generate platform environment file automatically
  ./generate_env.sh --auto
  docker-compose up --build --detach
  ./redeploy.sh --latest
}

function clonePlatform() {
  # Check for the presence of configurations
  test "$(ls ~/.ssh/*.pub 2>/dev/null)" && echo -n "$(tput setaf 2)$(tput bold)Config check passed!$(tput sgr0)" || exit 1
  echo -e "$(tput setaf 6)$(tput bold)\nThe platform components will be deployed to the server: $(tput sgr0)\n"

  # Clone platform repository
  echo "Enter the target directory for the platform $(tput setaf 2)[System: $(pwd)/$(hostname)]$(tput sgr0):"
  read serverDir
  git clone git@github.com:01-edu/all.git $serverDir
  cd $serverDir
  # Generate platform environment file automatically
  ./generate_env.sh --gen
}

if [[ ! -n ${1:-} ]] || [[ "--check" = $1 ]]; then
  echo -e "$(tput setaf 2)$(tput bold)Commencing configuration check: $(tput sgr0)"
  checkList
  echo -e "$(tput setaf 2)\nSystem configuration check complete! $(tput sgr0)\n"
  exit 0
elif [[ "--help" = $1 ]]; then
  echo "$(tput setaf 2) --check : to check the current configuration. $(tput sgr0)"
  echo "$(tput setaf 3) --run : to configure the system. $(tput sgr0)"
  echo "$(tput setaf 1) --reboot : to configure the system and reboot. $(tput sgr0)"
  echo "$(tput setaf 6) --deploy : to deploy and spin-up platform components. $(tput sgr0)"
  echo "$(tput setaf 5) --platform : to clone platform. $(tput sgr0)"
  echo "$(tput setaf 7) --help : to display this message. $(tput sgr0)"
elif [[ "--reboot" = $1 ]]; then
  echo -e "$(tput setaf 1)$(tput bold)\nSystem will be configured and rebooted. $(tput sgr0)"
  sysConfig
  echo -e "$(tput setaf 1)\nSystem configuration complete. Rebooting now... $(tput sgr0)"
  reboot
elif [[ "--run" = $1 ]]; then
  echo -e "$(tput setaf 3)$(tput bold)\nSystem will be configured without rebooting. $(tput sgr0)"
  sysConfig
  echo -e "$(tput setaf 3)\nSystem configuration complete! $(tput sgr0)"
  exit 0
elif [[ "--deploy" = $1 ]]; then
  deployCore
  deployPlatform
  echo -e "$(tput setaf 6)\nRepositories cloned  and platform has been deployed successfully! $(tput sgr0)"
  exit 0
elif [[ "--platform" = $1 ]]; then
  clonePlatform
  echo -e "$(tput setaf 5)\nPlatform has been cloned successfully! $(tput sgr0)"
  exit 0
else
  echo "$(tput setaf 1)$(tput bold) Unknown configuration option: $1 $(tput sgr0)"
  echo "$(tput setaf 1)Please use --help for all available options. $(tput sgr0)"
  echo "$(tput setaf 1)No changes are made $(tput sgr0)"
  exit 0
fi