module Gersion

# File lib/gersion.rb, line 7
def self.current_version
  the_current_tag || the_current_sha
end

# File lib/gersion.rb, line 11
def self.version_of gem
  find_the_gem_in_the_git_repos_section(gem) || find_the_gem_in_the_rubygems_section(gem)
end

# File lib/gersion.rb, line 28
def find_gem_version_in_content gem, content
  regex = Regexp.new("  #{gem} \\(([01234567890\.]*)\\)")
  find_the_match_between content, regex
rescue
  nil
end

# File lib/gersion.rb, line 18
def find_the_gem_in_the_git_repos_section gem
  if git_match = gemlock_content.split('GEM')[0].split('GIT').select { |c| find_gem_version_in_content(gem, c) }.first
    find_the_match_between(git_match, /tag: (.*)/) || find_the_match_between(git_match, /revision: (.*)/)
  end
end

# File lib/gersion.rb, line 24
def find_the_gem_in_the_rubygems_section gem
  find_gem_version_in_content gem, gemlock_content
end

# File lib/gersion.rb, line 39
def find_the_match_between content, regex
  content.scan(regex)[0][0]
rescue
  nil
end

# File lib/gersion.rb, line 35
def gemlock_content
  @gemlock_content ||= Gersion::File.read('Gemfile.lock')
end

# File lib/gersion.rb, line 49
def the_current_sha
  Gersion::Bash.run('git rev-list -1 HEAD').split("\n")[0]
end

# File lib/gersion.rb, line 45
def the_current_tag
  Gersion::Bash.run('git tag --points-at HEAD').split("\n")[0]
end