class Sentry::ReleaseDetector

def detect_release(project_root:, running_on_heroku:)
  detect_release_from_env ||
  detect_release_from_git ||
  detect_release_from_capistrano(project_root) ||
  detect_release_from_heroku(running_on_heroku)
end

def detect_release_from_capistrano(project_root)
  revision_file = File.join(project_root, 'REVISION')
  revision_log = File.join(project_root, '..', 'revisions.log')
  if File.exist?(revision_file)
    File.read(revision_file).strip
  elsif File.exist?(revision_log)
    File.open(revision_log).to_a.last.strip.sub(/.*as release ([0-9]+).*/, '\1')
  end
end

def detect_release_from_env
  ENV['SENTRY_RELEASE']
end

def detect_release_from_git
  Sentry.sys_command("git rev-parse --short HEAD") if File.directory?(".git")
end

def detect_release_from_heroku(running_on_heroku)
  return unless running_on_heroku
  ENV['HEROKU_SLUG_COMMIT']
end