#!/usr/bin/env bash
# failed to perform conditional arithmatic when using #!/bin/sh
# Made available under (CC BY-SA 3.0) https://creativecommons.org/licenses/by-sa/3.0/
# The menu system as modified from https://askubuntu.com/a/257766/957393
# The option_picked function is by Jeremy D. Gerdes seakintruth@gmail.com April 2019
# The install_if_missing is modified from https://stackoverflow.com/a/22592801/1146659
# -------------------------------------------------------------------------------------
# Before running this script Install R and Rstudio with/from:
# sudo apt install r-base
# https://rstudio.com/products/rstudio/download/#download
# -------------------------------------------------------------------------------------
# The most recent version of this script can be called by either one of:
# bash <(curl -s https://gist.githubusercontent.com/seakintruth/95d49b6ea316c2b8a6e283e1ee1a3f3a/raw)
# bash <(wget -q -O - https://gist.githubusercontent.com/seakintruth/95d49b6ea316c2b8a6e283e1ee1a3f3a/raw)

normal=`echo "\033[00;00m"`; # normal white
msgcolor=`echo "\033[01;31m"`; # bold red
fgred=`echo "\033[31m"`; # red
prmtmsg=`echo "Perform one of the following:\n - enter a R Vesion Number (i.e. 3.6.1)\n - pick an option from the menu\n - or ${fgred}x ${normal}to exit.\n:"` ;
menu=`echo "\033[36m"`; #Blue
number=`echo "\033[33m"`; #yellow
bgred=`echo "\033[41m"`;

install_if_missing() {
  # https://stackoverflow.com/a/22592801/1146659
  local package_name=$1
  if [ $(dpkg-query -W -f='${Status}' $package_name 2>/dev/null | grep -c "ok installed") -eq 0 ];  then
    echo -n "Attempt to install package $package_name? [yes or no]: "
    read yno
    case $yno in
      [yY] | [yY][Ee][Ss] )
        printf "Missing $package_name. Setting up $package_name. \n"
        sudo apt-get --yes install $package_name
        ;;
      [nN] | [nN][oO] )
        printf "Package $package_name is required \n"
        exit 1;
        ;;
      *)
        printf "Invalid Input \n"
        exit 1;
        ;;
    esac
  fi
}

option_picked(){
    local r_ver=$1
    local set_rstudio_version="/opt/R/$r_ver/bin/R";
    # if the expected file exist then we just launch for this version
    if test -f "$set_rstudio_version"; then
      echo "$set_rstudio_version exist"
    else
      r_major=`expr substr ${r_ver} 1 1`
      if [ "$r_major" = "1" ] || [ "$r_major" = "0" ]; then
        extention="tgz"
      else
        extention="tar.gz"
      fi
      R_Opt="/opt/R"
      if [ ! -d "$R_Opt" ]; then
        sudo mkdir $R_Opt
      fi
      local r_url=`echo "https://cran.r-project.org/src/base/R-$r_major/R-$r_ver.$extention"`
      # test if the desired web page exists
      # https://stackoverflow.com/a/2924444/1146659
      install_if_missing curl;
      curl -s --head $r_url | head -n 1 | grep "HTTP/1.[01] [23].." > /dev/null
      # $? will be 0 if curl url resturns 200 or 3* status
      if [ $? -eq 0 ];then
        printf "Getting file for installation:\n\t"
        echo -n "Attempt to install R version $r_ver? [yes or no]: "
        read yno
        case $yno in
          [yY] | [yY][Ee][Ss] )
            echo "Agreed, installing $r_ver"
            # install Dependancies
            install_if_missing libx11-dev;
            install_if_missing xorg-dev;
            install_if_missing libcurl4-openssl-dev;
            curl $r_url \
              --output ~/Downloads/R-$r_ver.$extention
            printf "~/Downloads/R-$r_ver.$extention ~/Downloads/"
            cd ~/Downloads && tar -xzvf ~/Downloads/R-$r_ver.$extention
            tar -xzvf ~/Downloads/R-$r_ver.$extention ~/Downloads/;
            rm ~/Downloads/R-$r_ver.$extention;
            cd ~/Downloads/R-$r_ver && \
            sudo ./configure --prefix=/opt/R/$r_ver --enable-R-shlib && \
            sudo make && \
            sudo make install
            if test -f "$set_rstudio_version"; then
              printf "Installation complete for $set_rstudio_version"
            else
              printf "Failed to install $set_rstudio_version "
              exit 1;
            fi
            # Cleanup install folder in ~/Downloads folder
            sudo rm -r -f ~/Downloads/R-$r_ver/
            local local_desktop=~/.local/share/applications
            if [ ! -d "$local_desktop" ]; then
              sudo mkdir $local_desktop
            fi
            if test -f "$local_desktop/name.desktop"; then
              # create a shortcut to this file if desktop file doesn't exist
              printf "You may need to edit the file $local_desktop/name.desktop to add this launcher to your applications"
            else
              local launcher_path=~/.local/share/RSTUDIO_Version_Launcher.sh
              curl https://gist.githubusercontent.com/seakintruth/95d49b6ea316c2b8a6e283e1ee1a3f3a/raw \
                  --output $launcher_path
              sudo chmod +x $launcher_path
              touch $local_desktop/r.desktop
              echo "[Desktop Entry]" >> "$local_desktop/r.desktop"
              echo "Type=Application" >> "$local_desktop/r.desktop"
              echo "Terminal=true" >> "$local_desktop/r.desktop"
              echo "Name=RSTUDIO_Version_Launcher" >> "$local_desktop/r.desktop"
              echo "Icon=/usr/lib/rstudio/rstudio.png" >> "$local_desktop/r.desktop"
              echo "Exec=$launcher_path" >> "$local_desktop/r.desktop"
              printf "/n Created launcher application shortcut $local_desktop/r.desktop /n"
              cat "$local_desktop/r.desktop"
            fi
            ;;
          [nN] | [n|N][O|o] )
            printf "Not agreed, you can't launch untill you agree to attempt an install of $r_ver \n";
            exit 1;
            ;;
          *)
            printf "Invalid input \n"
            exit 1;
            ;;
        esac
      fi
    fi
    local message="Attempting to Start RStudio $r_ver from path: \n\t ${normal}$set_rstudio_version";
    printf "${msgcolor}${message}${normal}\n";
    if [ -f "$set_rstudio_version" ]; then
      printf "$set_rstudio_version \n\t";
      export RSTUDIO_WHICH_R="$set_rstudio_version";
      install_if_missing screen;
      [[ ! -d /run/screen ]] && sudo /etc/init.d/screen-cleanup start;
      screen -d -m rstudio;
    else
      printf "Unable to find $set_rstudio_version \n"
    fi
    show_menu;
}
repeat() {
  local ts=$(printf "%${2}s");
  printf %s "${ts// /$1}";
}
display_menu_item(){
  local item_number=$1
  local version_number=$2
  # get character count: https://stackoverflow.com/a/31009961/1146659
  local ver_char_len=${#version_number}
  # repeat a space n number of times: https://stackoverflow.com/a/23426605/1146659
  let white_char_len=" 16 - $ver_char_len "
  local whitespace=`repeat " " $white_char_len`
  local end_first_column=29
  local end_second_column=59
  if (( $item_number > $end_second_column )); then
    printf "${menu}** ${number}$item_number) ${menu}$version_number${normal}\n";
  elif (( $item_number > $end_first_column )); then
    printf "${menu}** ${number}$item_number) ${menu}$version_number${normal}$whitespace";
  elif (( $item_number > 9 )); then
    printf "${menu}** ${number} $item_number) ${menu}$version_number${normal}$whitespace";
  else
    printf "${menu}**  ${number} $item_number) ${menu}$version_number${normal}$whitespace";
  fi
}
show_menu(){
  printf "\n${menu}*******************************************************${normal}\n";
  printf "Built for Ubuntu, Dependancy prior to running this script is 'RStudio'. \n";
  printf "If installation is required will prompt for sudo access to build from source.";
  printf "\n${menu}*******************************************************${normal}\n";
  printf "\n${menu}****** Select the Version of R to Launch RSTUDIO ******${normal}\n";
  printf "\n${menu}*******************************************************${normal}\n";
  display_menu_item 1 3.0.0; display_menu_item 30 2.0.0; display_menu_item 60 2.13.0
  display_menu_item 2 3.0.1; display_menu_item 31 2.0.1; display_menu_item 61 2.13.1
  display_menu_item 3 3.0.2; display_menu_item 32 2.1.0; display_menu_item 62 2.13.2
  display_menu_item 4 3.0.3; display_menu_item 33 2.1.1; display_menu_item 63 2.14.0
  display_menu_item 5 3.1.0; display_menu_item 34 2.2.0; display_menu_item 64 2.14.1
  display_menu_item 6 3.1.1; display_menu_item 35 2.2.1; display_menu_item 65 2.14.2
  display_menu_item 7 3.1.2; display_menu_item 36 2.3.0; display_menu_item 66 2.15.0
  display_menu_item 8 3.1.3; display_menu_item 37 2.3.1; display_menu_item 67 2.15.1-w
  display_menu_item 9 3.2.0; display_menu_item 38 2.4.0; display_menu_item 68 2.15.1
  display_menu_item 10 3.2.1; display_menu_item 39 2.4.1; display_menu_item 69 2.15.2
  display_menu_item 11 3.2.2; display_menu_item 40 2.5.0; display_menu_item 70 2.15.3
  display_menu_item 12 3.2.3; display_menu_item 41 2.5.1; display_menu_item 71 1.0.0
  display_menu_item 13 3.2.4; display_menu_item 42 2.6.0; display_menu_item 72 1.0.1
  display_menu_item 14 3.2.4-revised; display_menu_item 43 2.6.1; display_menu_item 73 1.1.0
  display_menu_item 15 3.2.5; display_menu_item 44 2.6.2; display_menu_item 74 1.2.0
  display_menu_item 16 3.3.0; display_menu_item 45 2.7.0; display_menu_item 75 1.3.0
  display_menu_item 17 3.3.1; display_menu_item 46 2.7.1; display_menu_item 76 1.3.1
  display_menu_item 18 3.3.2; display_menu_item 47 2.7.2; display_menu_item 77 1.4.0
  display_menu_item 19 3.3.3; display_menu_item 48 2.8.0; display_menu_item 78 1.4.1
  display_menu_item 20 3.4.0; display_menu_item 49 2.8.1; display_menu_item 79 1.5.0
  display_menu_item 21 3.4.1; display_menu_item 50 2.9.0; display_menu_item 80 1.5.1
  display_menu_item 22 3.4.2; display_menu_item 51 2.9.1; display_menu_item 81 1.6.0
  display_menu_item 23 3.4.3; display_menu_item 52 2.9.2; display_menu_item 82 1.6.1
  display_menu_item 24 3.4.4; display_menu_item 53 2.10.0; display_menu_item 83 1.6.2
  display_menu_item 25 3.5.0; display_menu_item 54 2.10.1; display_menu_item 84 1.7.0
  display_menu_item 26 3.5.1; display_menu_item 55 2.11.0; display_menu_item 85 1.7.1
  display_menu_item 27 3.5.2; display_menu_item 56 2.11.1; display_menu_item 86 1.8.0
  display_menu_item 28 3.5.3; display_menu_item 57 2.12.0; display_menu_item 87 1.8.1
  display_menu_item 29 3.6.0; display_menu_item 58 2.12.1; display_menu_item 88 1.9.0
  display_menu_item 90 3.6.1; display_menu_item 59 2.12.2; display_menu_item 89 1.9.1
  display_menu_item 91 3.6.2; display_menu_item 92 3.6.3; display_menu_item 93 4.0.0
  display_menu_item 94 4.0.1; display_menu_item 95 4.0.2; display_menu_item 96 4.0.3
  display_menu_item 97 4.0.4; display_menu_item 98 4.0.5; display_menu_item 99 4.1.0
  display_menu_item 100 4.1.1; display_menu_item x "exit launcher"
  printf "${menu}*********************************************${normal}\n";
  printf "$prmtmsg";
  read opt;
  while [ "$opt" != "" ]; do
      if [ "$opt" = "x" ]; then
        exit;
      else
        case $opt in
          1) option_picked "3.0.0";;
          2) option_picked "3.0.1";;
          3) option_picked "3.0.2";;
          4) option_picked "3.0.3";;
          5) option_picked "3.1.0";;
          6) option_picked "3.1.1";;
          7) option_picked "3.1.2";;
          8) option_picked "3.1.3";;
          9) option_picked "3.2.0";;
          10) option_picked "3.2.1";;
          11) option_picked "3.2.2";;
          12) option_picked "3.2.3";;
          13) option_picked "3.2.4";;
          14) option_picked "3.2.4-revised";;
          15) option_picked "3.2.5";;
          16) option_picked "3.3.0";;
          17) option_picked "3.3.1";;
          18) option_picked "3.3.2";;
          19) option_picked "3.3.3";;
          20) option_picked "3.4.0";;
          21) option_picked "3.4.1";;
          22) option_picked "3.4.2";;
          23) option_picked "3.4.3";;
          24) option_picked "3.4.4";;
          25) option_picked "3.5.0";;
          26) option_picked "3.5.1";;
          27) option_picked "3.5.2";;
          28) option_picked "3.5.3";;
          29) option_picked "3.6.0";;
          30) option_picked "2.0.0";;
          31) option_picked "2.0.0";;
          32) option_picked "2.0.1";;
          33) option_picked "2.1.0";;
          34) option_picked "2.1.1";;
          35) option_picked "2.2.1";;
          36) option_picked "2.3.0";;
          37) option_picked "2.3.1";;
          38) option_picked "2.4.0";;
          39) option_picked "2.4.1";;
          40) option_picked "2.5.0";;
          41) option_picked "2.5.1";;
          42) option_picked "2.6.0";;
          43) option_picked "2.6.1";;
          44) option_picked "2.6.2";;
          45) option_picked "2.7.0";;
          46) option_picked "2.7.1";;
          47) option_picked "2.7.2";;
          48) option_picked "2.8.0";;
          49) option_picked "2.8.1";;
          50) option_picked "2.9.0";;
          51) option_picked "2.9.1";;
          52) option_picked "2.9.2";;
          53) option_picked "2.10.0";;
          54) option_picked "2.10.1";;
          55) option_picked "2.11.0";;
          56) option_picked "2.11.1";;
          57) option_picked "2.12.0";;
          58) option_picked "2.12.1";;
          59) option_picked "2.12.2";;
          60) option_picked "2.13.0";;
          61) option_picked "2.13.1";;
          62) option_picked "2.13.2";;
          63) option_picked "2.14.0";;
          64) option_picked "2.14.1";;
          65) option_picked "2.14.2";;
          66) option_picked "2.15.0";;
          67) option_picked "2.15.1-w";;
          68) option_picked "2.15.1";;
          69) option_picked "2.15.2";;
          70) option_picked "2.15.3";;
          71) option_picked "1.0.0";;
          72) option_picked "1.0.1";;
          73) option_picked "1.1.0";;
          74) option_picked "1.2.0";;
          75) option_picked "1.3.0";;
          76) option_picked "1.3.1";;
          77) option_picked "1.4.0";;
          78) option_picked "1.4.1";;
          79) option_picked "1.5.0";;
          80) option_picked "1.5.1";;
          81) option_picked "1.6.0";;
          82) option_picked "1.6.1";;
          83) option_picked "1.6.2";;
          84) option_picked "1.7.0";;
          85) option_picked "1.7.1";;
          86) option_picked "1.8.0";;
          87) option_picked "1.8.1";;
          88) option_picked "1.9.0";;
          89) option_picked "1.9.1";;
          90) option_picked "3.6.1";;
          91) option_picked "3.6.2";;
          92) option_picked "3.6.3";;
          93) option_picked "4.0.0";;
          94) option_picked "4.0.1";;
          95) option_picked "4.0.2";;
          96) option_picked "4.0.3";;
          97) option_picked "4.0.4";;
          98) option_picked "4.0.5";;
          99) option_picked "4.1.0";;
          100) option_picked "4.1.1";;
          [xXqQ][eE] | [eE][xX][iI][tT] | [qQ][uU][iI][tT] ) exit;;
          \n)exit;;
          *)
            # if the length of the option picked is >=3 assume a version # is passed
            if [ ${#opt} -ge 3 ]; then
              option_picked $opt;
            else
              echo "done";
            fi
            show_menu;
          ;;
        esac
      fi
  done
}
show_menu;