#!/bin/bash

# This script will install IPFS software and establish initial settings.
# This must be executed with root privileges or with sudo.

if [[ $(id -u) -ne 0 ]] ; then echo "Please run as root, or prefix with 'sudo'" ; exit 1 ; fi

# Calculate disk space available for IPFS
FREE=`df --output=avail -B 1 / | tail -n 1` # Free space in bytes on root partition
MAX=`expr $FREE / 1320000000`      # Approximately 75% of free space (in GB)
printf -v STORAGE_MAX %dG $MAX     # The default StorageMax parameter value

AUTO=0                             # Default autostart method 0 == systemd, 1 == cron @reboot
WAIT=0                             # Default value for single step / debug mode (no wait)
DISTUP=0                           # Default value for dist-upgrade (don't do it!)
RPI_UFW=0                          # Default value to install firewall on RPi (no)
GOVER=NoGo                         # Default Go language version (Don't use go version)
DEFGO=1.10.1                       # Default version to use (tho now -g requires version)

CONFIG=/home/ipfs/.ipfs/config     # IPFS configuration file

usage() {
  echo "$0 [-a] [-d] [-g <version> ] [-m <int> ] [-w] [-h | --help]"
  echo "-a == autostart method. Use cron @reboot instead of systemd unit"
  echo "-d == distribution upgrade. Specify -d to do a dist-upgrade"
  echo "-f == firewall on Raspberry Pi. Default is no. Use -f to enable on the RPi"
  echo "-g == go version. -g requires a version"
  echo "-m == max storage space. Default is 75% of disk. Option value integer in gigabytes"
  echo "-w == Wait after each step / debug mode. Default is no waiting"
  echo "-h == print this usage info and exit. Also for --help"
}

# Determine OpSys (Raspbian or Debian)
OS=`lsb_release -is`
if [[ $OS != "Raspbian" && $OS != "Debian" ]]; then
   echo "$OS Linux detected! This script is for Raspbian or Debian only for now."
   exit 1
fi
if [ $OS == "Raspbian" ]; then
  ARCH=armv6l;
else
  ARCH=amd64;                      # No support for 32 bit systems; should we?
fi

# Make sure we have enhanced getopt -- probably not required for most Linux distros
getopt --test
if [ $? -ne 4 ]; then echo "Ouch! getopt not available on this system - Bye!"; exit 1; fi

# Process command line options
# NOTE: double colons after g option (should be optional param for -g) swallows -m !!!
# getopt from util-linux 2.29.2 on Raspbian Stretch Lite OS, 4/8/2019 release
OPTS=`getopt -o adfg:m:wh --long help -n "$0" -- "$@"`
eval set -- "$OPTS"

# extract options and their arguments and set appropriate variables.
while true; do
    case "$1" in
        -a) AUTO=1;    shift ;;
        -d) DISTUP=1;  shift ;;
        -f) RPI_UFW=1; shift ;;
        -g) if [ "$2" != "" ]; then
              GOVER=$2
              echo "Will use golang version $GOVER"
            else
              GOVER=$DEFGO
            fi
            shift 2
            ;;
        -m) if ! [ -z "${2//[0-9]}" ]; then          # Positive number?
              echo "-m requires a positive integer (gigabytes)"
              exit 1
            fi
            STORAGE_MAX="$2G";
            shift 2
            ;;
        -h|--help) usage; exit 0 ;;
        -w) WAIT=1; shift ;;
        --) shift;  break ;;
        *) echo "No such option: $1" >&2; exit 1 ;;
    esac
done

# Show options parsed for this installation
echo "OS=$OS, ARCH=$ARCH, AUTO=$AUTO, DISTUP=$DISTUP, RPI_UFW=$RPI_UFW, GOVER=$GOVER, STORAGE_MAX=$STORAGE_MAX, WAIT=$WAIT"
echo ""
if [ $WAIT == 1 ]; then read -n 1 -p "Press ^C to exit, any other key to proceed..." key; fi

if [ ! -f ready4ipfs ]; then
  ping -q -w 1 -c 1 storage.googleapis.com > /dev/null 2>&1
  if [ $? -ne 0 ]; then
    if [ $OS == "Raspbian" ]; then
      # Make sure the system is configured for network access
      echo ""
      echo "The system must be configured, at least to setup networking."
      echo "REBOOT if raspi-config asks, then run this again when rebooted."
      echo "You can just exit raspi-config the second time, don't reboot."
      read -n 1 -p "Press any key to launch the raspi-config utility..." key
      raspi-config
    else
      echo ""
      echo "It doesn't appear the system is online. Make sure networking"
      echo "is operational, then try again. Bye for now!"
      exit -1
    fi
  fi
  echo "Updating the OS (Operating System)..."
  apt-get -y update
  apt-get -y upgrade
  touch ready4ipfs
  if [ $DISTUP == 1 ]; then
    echo ""
    echo "Performing a distribution upgrade, which may bump OS / kernel version..."
    apt-get -y dist-upgrade
    echo ""
    echo "Need to reboot. Afterwards, rerun this script to finish IPFS installation."
    read -n 1 -p "Press ^C to abort, or any other key to reboot..." key
    reboot
  fi
fi

if [ ! -d /home/ipfs ]; then
  echo "Preparing the ipfs user account..."
  if [ ! -d /home/ipfs ]; then useradd -m -s /bin/bash ipfs; fi
  if [ ! -d /home/ipfs/.ipfs ]; then mkdir /home/ipfs/.ipfs; fi
  if [ $GOVER != "NoGo" ]; then
    mkdir /home/ipfs/go
    echo "source /usr/local/bin/goInit" >> /home/ipfs/.profile  # Sets PATH and GOPATH
  fi
  chown -R ipfs.ipfs /home/ipfs
  echo ""
  if [ $WAIT == 1 ]; then read -n 1 -p "Press ^C to exit, any other key to proceed..." key; fi
fi

if [ "$GOVER" == "NoGo" ]; then
  if [ ! -e /etc/apt/sources.list.d/siderus.list ]; then
    echo "Installing credentials for siderus software repository..."
    apt install -y apt-transport-https curl
    curl https://get.siderus.io/key.public.asc | apt-key add -
    echo "deb https://get.siderus.io/ apt/" | tee -a /etc/apt/sources.list.d/siderus.list
    IPFS=/usr/bin/ipfs
    apt update
  fi
else  # Install requested go language version if not already installed
  if [ ! -e "/usr/local/bin/go$GOVER.linux-$ARCH.tar.gz" ]; then
    pushd /usr/local/bin
    echo "Installing binary golang version $GOVER from googleapis. Please be patient..."
    wget https://storage.googleapis.com/golang/go$GOVER.linux-$ARCH.tar.gz
    tar -C /usr/local -xzf go$GOVER.linux-$ARCH.tar.gz
    popd
  fi

  # Create a bit of code to set env vars for all to source in their .profile
  echo 'export GOPATH=/home/$USER/go' > /usr/local/bin/goInit
  echo 'export PATH=$PATH:/usr/local/go/bin:$GOPATH/bin' >> /usr/local/bin/goInit

  # Don't add to .profile if it's already there
  if ! grep -Fq goInit ~/.profile; then
    echo "source /usr/local/bin/goInit" >> ~/.profile
  fi
  source ~/.profile # We need those vars now to proceed

  VER=`go version`  # Verify Installation
  if [[ ! "$VER" =~ $GOVER ]]; then
    echo "Bummer - failed to install go version $GOVER, Bye!"
    exit -1
  else
    echo "$VER is installed"
    if [ ! -d /root/go ]; then mkdir /root/go; fi
  fi
fi
echo ""
if [ $WAIT == 1 ]; then read -n 1 -p "Press ^C to exit, any other key to proceed..." key; fi

echo "Installing IPFS and supporting packages. Please be patient..."
apt-get -y install git tmux
if [[ $OS != "Raspbian" || $RPI_UFW == 1 ]]; then apt-get -y install ufw; fi
if [ $GOVER == "NoGo" ]; then
  apt-get -y install ipfs
else
  IPFS=/home/ipfs/go/bin/ipfs              # This is used for systemD unit
  if [ ! -e "/usr/local/bin/ipfs-update" ]; then
    echo "Installing ipfs-update..."
#   runuser -l ipfs -c 'go get -u github.com/ipfs/ipfs-update' # No worky anymore!
    curl https://dist.ipfs.io/ipfs-update/v1.5.2/ipfs-update_v1.5.2_linux-arm.tar.gz > ipfsUpdate.tgz
    tar -xzf ipfsUpdate.tgz
    mv ipfs-update/ipfs-update /usr/local/bin/.  # Copy binary into place
    if [ "`which ipfs-update`" != "/usr/local/bin/ipfs-update" ]; then
      echo "Ouch - failed to install ipfs-update, Bye!"
      exit -1
    else
      rm -rf ipfs-update  # Remove the folder
    fi
  fi
  if [ "`which ipfs`" != "/usr/local/bin/ipfs" ]; then
    echo "Installing latest version of ipfs..."
    runuser -l ipfs -c 'ipfs-update install latest'
#    runuser -l ipfs -c 'ipfs-update --verbose install --no-check latest'
    if [ "`which ipfs`" != "/usr/local/bin/ipfs" ]; then
      echo "ipfs-update failed to install ipfs, Bye!"
      exit -1
    fi
  fi
fi

# Initialize IPFS and log output
runuser -l ipfs -c 'ipfs init --profile server > ~/.ipfs/init.log 2>&1'
apt -y autoremove
echo ""
if [ $WAIT == 1 ]; then read -n 1 -p "Press ^C to exit, any other key to proceed..." key; fi

if [[ $OS != "Raspbian" || $RPI_UFW == 1 ]]; then
  echo "Opening required firewall ports..."
  ufw allow 4001/tcp
  ufw allow 22/tcp
  echo ""
  if [ $WAIT == 1 ]; then read -n 1 -p "Press ^C to exit, any other key to proceed..." key; fi
fi

echo "Setting maximum IPFS storage to $STORAGE_MAX in config file..."
sed -i "s/^\s*\"StorageMax.*$/    ~StorageMax~: ~$STORAGE_MAX~,/g" $CONFIG
sed -i "s/~/\"/g" $CONFIG
echo ""
if [ $WAIT == 1 ]; then read -n 1 -p "Press ^C to exit, any other key to proceed..." key; fi

if [ $AUTO == 0 ]; then  # For some unknown reason this doesn't always work on debian minimal server
  echo "Creating SystemD unit to start IPFS on reboot..."
  (
  cat <<SYSD_UNIT
[Unit]
Description=IPFS daemon
After=network.target
[Service]
User=ipfs
LimitNOFILE=65536
Environment="IPFS_FD_MAX=4096"
Environment="IPFS_PATH=/home/ipfs/.ipfs"
ExecStart=$IPFS daemon --enable-namesys-pubsub
Restart=on-failure
[Install]
WantedBy=multi-user.target
SYSD_UNIT
) > /etc/systemd/system/ipfs.service

  systemctl enable ipfs
  systemctl start ipfs

else # Use this alternate way to start service on system start
  echo "#!/bin/bash" > /home/ipfs/autostart.bash
  echo ". /usr/local/bin/goInit" >> /home/ipfs/autostart.bash
  echo "export LimitNOFILE=65536" >> /home/ipfs/autostart.bash   # Might not work as env
  echo "export IPFS_FD_MAX=4096" >> /home/ipfs/autostart.bash
  echo "export IPFS_PATH=/home/ipfs/.ipfs" >> /home/ipfs/autostart.bash
  echo "/home/ipfs/go/bin/ipfs daemon --enable-namesys-pubsub" >> /home/ipfs/autostart.bash
  echo "@reboot ipfs /bin/bash /home/ipfs/autostart.bash" > /etc/cron.d/autoStart
  chmod 755 /etc/cron.d/autoStart
fi

cat /home/ipfs/.ipfs/init.log
echo "IPFS is now installed on this system."
echo ""
echo "Now set a password for the ipfs account. Press ^C and abort this now"
echo "unless you are certain you have setup your system with appropriate"
echo "locale, keyboard etc. Otherwise you may not be able to login."
passwd ipfs