#!/usr/bin/env bash
# Copyright (c) 2013-2106 All Right Reserved  Alec Clews
#
# author: Alec Clews
# alecclews@gmail.com
#
#    This program is free software; you can redistribute it and/or modify
#    it under the terms of the GNU General Public License as published by
#    the Free Software Foundation; either version 2 of the License, or
#    (at your option) any later version.
#
#    This program is distributed in the hope that it will be useful,
#    but WITHOUT ANY WARRANTY; without even the implied warranty of
#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#    GNU General Public License for more details.
#
#    You should have received a copy of the GNU General Public License along
#    with this program; if not, write to the Free Software Foundation, Inc.,
#    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
#
#
# NB These Scripts support Pi Raspian (Debian)


export UPDATE_LABEL="Updated_$(date +%F)"

setConfigOption() {
  CONFIG_FILE=/boot/config.txt
  if grep "$1=" $CONFIG_FILE ; then
    sudo sed --in-place -re "s/^#?$1=.+$/$1=$2 #$UPDATE_LABEL/" $CONFIG_FILE
  else
    echo $1=$2'  #'$UPDATE_LABEL| sudo tee -a $CONFIG_FILE
  fi
}

export -f setConfigOption


ask() {
  read -p "$1" -r < /dev/tty
  echo $REPLY
}

# Get updated package list
sudo apt-get update

# Make sure we using the lastest version of config script
sudo apt-get install -y raspi-config

echo
echo I suggest removing the Wolframe engine as it\'s of limited use in IoT
echo projects. It will save about 1/2G of disk space and a *lot* of time
echo during upgrades


if [[ $(ask "Do you wish to remove Wolframe engine? [y/N] ") =~ ^[Yy]$ ]]
then
#save 1/2G of space
        sudo apt-get -y purge wolfram-engine
fi

echo
echo
echo 'About to start the Raspbery Pi config program (raspi-config).'
echo When you are happy with the configuration exit the program and
echo we will continue with the rest of the setup.
echo At a miniumum you should configure locale, keyboard and timezone.
echo Also consider setting up memory GPU split and CPU clocking
echo Depending on your project you may also want to set up camera, i2c etc.
echo
echo
echo NOTE: If you are prompted to reboot when running this program answer NO.
echo If you make a mistake and say \"yes\" to reboot, don\'t worry. Just run this process again.
echo

read -p "Press enter when ready" < /dev/tty

sudo raspi-config


oldhostname=$(cat /etc/hostname)
echo
echo It is highly recommended that the hostname is changed to something unique on the network.
echo If you can\'t think of anything I suggest something like \<yourName\>pi\<n\> where
echo n is some single digit number. The current hostname is \"$oldhostname\"
echo

if [[ $(ask "Do you wish to change the hostname?[y/N]  ") =~ ^[Yy]$ ]]
then

  read -p  "Please enter the hostname (lowercase letters, \"-\" and numbers only) " -r < /dev/tty

  echo $REPLY | sudo tee /etc/hostname > /dev/null

  sudo sed -ie 's/^\(..*\)'$oldhostname'\(.*\)$/\1'$REPLY'\2/' /etc/hosts

else
  echo
fi


# Rename the pi user account
echo
echo "You will now be offered to the chance to change the user name of the current user account"
echo "from $USER to something of your own choosing"
echo
echo "N.B. If this process fails you will probably have to re-image your SD card"
echo

if [[ $(ask "Do you wish to rename the $USER user account?[y/N] ") =~ ^[Yy]$ ]]
then

    read -p  "Please enter the new user name " -r < /dev/tty

cat <<'EOF' | sudo bash -s $USER $REPLY $HOME
     for i in /etc/group /etc/passwd /etc/sudoers /etc/shadow ; do
          sed -rie '/\b'$1'\b/s/\b'$1'\b/'$2'/g' $i
     done
     mv $3 /home/$2
EOF

    USER=$REPLY

    echo "User name changed to $USER"
else
  echo
fi

echo If all has gone well you will be able to access this device using ssh $USER@$(cat /etc/hostname).local
echo assuming you have Bonjour support on your ssh terminal workstation

echo "System will now reboot. Afterwards please login as $USER and the setup process will continue"
read -p "Press any key to continue " -n 1 -r < /dev/tty