install_gems

#!/usr/bin/env ruby
def parse_missing_required(input)
  matches = input.match(/Missing these required gems:([\s\S]*)You're running:/)
  matches[1].strip.split("\n").map do |line|
    m = line.match(/^\s*(\S+)\s+(\S+\s+[0-9.]+)/)
    p line if m.nil?
    {:name => m[1], :version => m[2]}
  end
end

def parse_missing_rake(input)
  matches = input.scan(/\s+-\s+\[ \]\s+(\S+)\s+(\S+\s+[0-9.]+)/)
  matches.map do |match|
    {:name => match[0], :version => match[1]}
  end
end

def get_requirements
  puts ">>> rake gems"
  result = `rake gems 2>&1`
  if result =~ /Missing these required gems:/
    parse_missing_required result
  else
    parse_missing_rake result
  end
end

$installed_gems = []

def install_gem!(gemspec)
  raise "Already installed #{gemspec[:name]} once. Make sure that GEM_HOME and GEM_PATH are set correctly." $installed_gems.include? gemspec[:name]
  $installed_gems << gemspec[:name]
  puts ">>> gem install #{gemspec[:name]} --version '#{gemspec[:version]}'"
  puts `gem install #{gemspec[:name]} --version '#{gemspec[:version]}'`
end

def install_all!
  puts "[Checking for missing requirements]"
  requirements = get_requirements
  if requirements.any?
    puts "[Installing missing requirements]"
    if `whoami`.strip != 'root'
      puts "Must be run as root"
      exit -1
    end
    requirements.each do |gemspec|
      install_gem! gemspec
    end
    install_all!
  end
end

install_all!