pryrails [-h] [-v] 

This program adds the gem 'pry-rails' to a file  in the current directory
The default  is 'Gemfile', which will usually exist in the root directory of a Ruby-on-Rails application. 
The gem 'pry' must be pre-installed in your system, or be present in 

        (1) If a development group does not exist, the gem is added to a new development group
        (2) If a development group exists and is in 'do-end' format, the gem is added to that group
        (3) If a development group exists and is NOT in 'do-end' format, the program exits
        (4) If the gem is already present, the program exits 

        -h: get help
        -v: verbose mode. Gives more information on the changes made 

    REQUIREMENTS
        (1) A file called  in the current directory.
            (the default  is 'Gemfile') 
        (2) The 'pry' gem must be installed on your system, or be present in 


    EXAMPLE USAGE
      pryrails
      pryrails -v
      pryrails  Gemfile_alt
      pryrails -v Gemfile_alt
      pryrails -h

#!/bin/bash

 declare myverbose=0

 # functions
 is_pry_gem_installed_on_system () {
     echo "$(gem list | grep -c  'pry[^\-]')"
 }

 is_pry_gem_present_in_file () {
     echo "$(grep -v '#' Gemfile | grep 'gem' |  grep -c  'pry[^\-]')"
 }
 is_gem_present () {
     echo "$(grep -nv '#' "${1}" | grep -c ${2-'pry-rails'})"
 }

 does_development_group_with_do_keyword_exist (){
     echo "$(grep -v  '#'  "${1}" | grep -v 'test'|  grep -c  '[[:space:]]\{0,3\}group[[:space:]]\{0,3\}:development[[:space:]]\{0,3\}do')"
 }

 does_any_development_group_exist (){
     echo "$(grep -v '#' "${1}"| grep -v 'test' |  grep -c '[[:space:]]\{0,3\}group[:]*[[:space:]]\{0,3\}:development')"
 }

 print_match () {
     echo "$(sed -n '/:development[[:space:]]\{1,3\}do/,/end/p' ${myfile})"
 }

 add_gem_to_group () {
     sed -i "/[[:space:]]\{0,3\}group[[:space:]]\{0,3\}:development[[:space:]]\{0,3\}do/a \ \ \ \ gem 'pry-rails'" "${1}"
 }

 add_group_and_gem () {

     if [[ $(wc -l < ${myfile}) -ge 10 ]];then 
         sed -i "10i gem 'pry-rails', group: :development" "${1}"
     else
         echo "gem 'pry-rails', group: :development" >> "${1}"
     fi
 }

 verbose_mode () {
     echo "The total group count is ${total_development_group_count}"
     echo "the count-do count is ${development_group_with_do_count}"
     echo "the var verbose is ${myverbose}"
 }

 does_gemfile_exist () {
     echo "$(ls | grep -c "${1}")"
 }

 user_choice () {

     read -p  "Do you wish to continue[Y/n]?" userchoice

     if [[ $userchoice == "Y" ||  $userchoice == "Yes" ]]; then
         echo "OK, done"
     else
         echo "Exiting at user request"
         exit 1
     fi
 }

 line_number_of_added_pattern () {
    echo "$(grep -vn '#' ${myfile} | grep 'pry-rails' |cut -f1 -d:| tr -t '\n' ','|sed '$s/,$//')"
 }

 line_number_of_development_groups () {
     echo "$(grep -nv '#' ${myfile} | grep -v 'test'| grep ':development'| cut -f1 -d:| tr -t '\n' ','|sed '$s/,$//')"
 }
 usage () {
 cat <

 This program adds the gem 'pry-rails' to a file  in the current directory
 The default  is 'Gemfile', which will usually exist in the root directory of a Ruby-on-Rails application. 
 The gem 'pry' must be pre-installed in your system, or be present in 

         (1) If a development group does not exist, the gem is added to a new development group
         (2) If a development group exists and is in 'do-end' format, the gem is added to that group
         (3) If a development group exists and is NOT in 'do-end' format, the program exits
         (4) If the gem is already present, the program exits 

         -h: get help
         -v: verbose mode. Gives more information on the changes made 

     REQUIREMENTS
         (1) A file called  in the current directory.
             (the default  is 'Gemfile') 
         (2) The 'pry' gem must be installed on your system, or be present in 


     EXAMPLE USAGE
       pryrails
       pryrails -v
       pryrails  Gemfile_alt
       pryrails -v Gemfile_alt
       pryrails -h
 END
 }

 ## Set options
 while getopts ":vh" opt; do
     case $opt in
         v)
             myverbose=1
             ;;
         h)
             usage | less
             exit 1
             ;;
     esac
 done

 shift $(( ${OPTIND} - 1 ))

 declare myfile=${1-'Gemfile'}

 if [[ $(does_gemfile_exist "${myfile}") -eq 0 ]];then
     echo "${myfile} does not exit"
     echo "Exiting"
     exit 1
 fi

 declare pry_gem_on_system_count="$(is_pry_gem_installed_on_system)"
 declare pry_gem_in_file_count="$(is_pry_gem_present_in_file "${myfile}")"
 declare pry_rails_count="$(is_gem_present "${myfile}")"
 declare total_development_group_count="$(does_any_development_group_exist ${myfile})"
 declare development_group_with_do_count="$(does_development_group_with_do_keyword_exist ${myfile})"

 if [[ ${pry_gem_on_system_count}  -eq 0 && ${pry_gem_in_file_count} -eq 0 ]];then
     echo "oooooops"
     exit 1
 fi

 if [[ ${pry_rails_count}  -ne 0 ]];then
     echo "You appear to already have pry-rails installed"
     echo "Check ${myfile}, LINE $(line_number_of_added_pattern). Exiting"
     exit 1
 fi

 if [[ ${total_development_group_count} -gt 1 ]];then
     echo "You appear to have more than one development group"
     echo "Check lines $(line_number_of_development_groups) of ${myfile}"
     echo "Exiting ..."
     exit 1
 fi

 if [[ ${total_development_group_count} -eq 1 && ${development_group_with_do_count} -eq 0 ]];then

     echo "Production group is not of the right syntax. Cannot help"
     echo "Check line $(line_number_of_development_groups) of ${myfile}. Exiting"
     exit 1
 fi

 if [[ ${total_development_group_count} -eq 1 && ${development_group_with_do_count} -eq 1 ]];then

     echo "gem 'pry-rails' will be added to the the following group (Line $(line_number_of_development_groups))"
     print_match 
     user_choice
     add_gem_to_group ${myfile}

     if [[ ${myverbose} -eq 1 ]];then
         echo "* The following change has been made (Line $(line_number_of_added_pattern))"
         print_match
         exit 0
     fi
     exit 0
 fi

 if [[ ${total_development_group_count} -eq 0 ]];then

     echo "The following line will be added to ${myfile}"
     echo "    gem 'pry-rails', group: :development"

     user_choice
     add_group_and_gem ${myfile}

     if [[ ${myverbose} -eq 1 ]];then
         echo "Requested change made on line $(line_number_of_added_pattern)"
         exit 0
     fi
     exit 0
 fi