class Primer::Deprecations

def correctable?(component_name)
  dep = registered_deprecations[component_name]
  return false if dep.nil?
  dep[:autocorrect]
end

def deprecated?(component_name)
  # if the component is registered, it is deprecated
  registered_deprecations.key?(component_name)
end

def deprecated_components
  registered_deprecations.keys.sort
end

def deprecation_message(component_name)
  return nil unless deprecated?(component_name)
  msg = ["'#{component_name}' has been deprecated."]
  # this nested structure is complex, because it has to
  # match all of the valid scenarios for a component being
  # replaceable, auto-correctable, and having a guide. for
  # more information on what is and is not valid, see the
  # documentation here: docs/contributors/deprecations.md
  if replacement?(component_name)
    msg << "Please update your code to use '#{replacement(component_name)}'."
    msg << "Use Rubocop's auto-correct, or replace it yourself." if correctable?(component_name)
    msg << "See #{guide(component_name)} for more information." if guide?(component_name)
  else # if there is no replacement, it must have a guide. this is enforced through tests
    msg << "Unfortunately, there is no direct replacement."
    msg << "See #{guide(component_name)} for more information and available options."
  end
  msg.join(" ")
end

def guide(component_name)
  dep = registered_deprecations[component_name]
  return nil if dep.nil?
  dep[:guide]
end

def guide?(component_name)
  !guide(component_name).nil?
end

def register(file_path)
  data = YAML.load_file(file_path)
  data["deprecations"].each do |dep|
    register_deprecation(dep["component"], {
                           autocorrect: dep["autocorrect"],
                           guide: dep["guide"],
                           replacement: dep["replacement"]
                         })
  end
end

def register_deprecation(component, options)
  registered_deprecations[component] = {
    autocorrect: options[:autocorrect],
    guide: options[:guide],
    replacement: options[:replacement]
  }
end

def registered_deprecations
  @registered_deprecations ||= {}
end

def replacement(component_name)
  dep = registered_deprecations[component_name]
  return nil if dep.nil?
  dep[:replacement]
end

def replacement?(component_name)
  !replacement(component_name).nil?
end