install

#!/bin/bash
#
# Usage: install 
# 1. Creates .standard_aliases directory in home directory.
# 2. Makes a symbolic link from there to standard_functions file
#    located in projects root.
# 3. Copies standard_rc from projects root to home directory as
#    .standardrc
# 4. Adds command to the end of .bashrc, that will update
#    project every time bash starts (by running make in projects
#    root) and import standard_functions and automatically 
#    generated file ~/.standard_aliases/aliases

# Stops execution if any command fails.
set -eo pipefail

createLinkSafely() {
  link="$1"
  targetDirectory=$(dirname "$link")
  file="$2"
  # Creates directory if it doesn't exist.
  if [ ! -d "$targetDirectory" ]; then
    echo "install: Creating directory $targetDirectory."
    mkdir -p "$targetDirectory"
  fi
  # Creates link if file doesn't exist.
  if [[ ! -f "$link" ]]; then
    echo "install: Creating link $link"
    ln -s $(pwd)/"$file" "$link" 
  else
    echo "install: Did not create link $link, because file with same name already exists."
  fi  
}

copyFileSafely() {
  destination="$1"
  origin="$2"
  # Copies file if file doesn't exist.
  if [[ ! -f "$destination" ]]; then
    echo "install: Copying file $origin to $destination"
    cp "$origin" "$destination" 
  else
    echo "install: Did not copy file $link, because file with same name already exists."
  fi  
}

main() {
  # Checks if make is installed.
  make --help &> /dev/null
  makeInstalled=1
  if [[ "$?" != 0 ]]; then
    makeInstalled=0
  fi
  # 1. Creates .standard_aliases directory in home directory.
  # 2. Makes a symbolic link from there to standard_functions file
  #    located in projects root.
  createLinkSafely ~/.standard_aliases/functions standard_functions
  # 3. Copies standard_rc from projects root to home directory as
  #    .standardrc (also comments out functions whose names have 
  #    already been taken by an alias (specified in .bashrc, 
  #    .profile or .bash_aliases).
  (cd scripts
  temp=$(mktemp /tmp/XXXXXXXX)
  ./remove-conflicts-from-rc.py > "$temp"
  copyFileSafely ~/.standardrc "$temp"
  )
  # Creates ~/.bashrc if it doesn't exist.
  if [[ ! -f ~/.bashrc ]]; then
    touch ~/.bashrc
  fi
  # 4. Adds command to the end of .bashrc, that will update
  #    project every time bash starts (by running make in projects
  #    root) and import standard_functions and automatically 
  #    generated file ~/.standard_aliases/aliases
  if [[ -z $(grep ". ~/.standard_aliases" ~/.bashrc) ]]; then
    cat ./scripts/resources/append-to-bashrc >> ~/.bashrc
  fi
  # Prints information on how to install Make if it is not 
  # installed, otherwise runs `bash`, so that changes take
  # effect.
  if [[ ! "$makeInstalled" ]]; then
    echo "Make command is missing, you need to install it first with:"
    echo "  sudo apt-get install make"
    echo "if you're running Debian/Ubuntu/Mint... or"
    echo "  sudo yum install make"
    echo "if you're running RedHat/Fedora/CentOS..."
    echo "After installing Make, run 'bash' for changes to take effect."
  else
    bash
  fi
}

main "$@"