class RuboCop::Formatter::HTMLFormatter

def file_finished(file, offenses)
  output_hash[:files] << hash_for_file(file, offenses)
  output_hash[:summary][:offense_count] += offenses.count
end

def finished(inspected_files)
  output_hash[:summary][:inspected_file_count] = inspected_files.count
  template = File.read(File
    .expand_path('../../../../assets/output.html.erb', __FILE__))
  erb = ERB.new(template)
  html_content = erb.result(binding)
  output.write html_content
end

def hash_for_file(file, offenses)
  {
    path:     relative_path(file),
    offenses: offenses.map { |o| hash_for_offense(o) }
  }
end

def hash_for_location(offense)
  {
    line:   offense.line,
    column: offense.real_column,
    length: offense.location.length,
    source_line: offense.location.source_line,
    highlight: highlight_line(offense.location)
  }
end

def hash_for_offense(offense)
  {
    severity: offense.severity.name,
    message:  offense.message,
    cop_name: offense.cop_name,
    corrected: offense.corrected?,
    location: hash_for_location(offense)
  }
end

def highlight_line(location)
  column_length = if location.begin.line == location.end.line
                    location.column_range.count
                  else
                    location.source_line.length - location.column
                  end
  ' ' * location.column + '^' * column_length
end

def initialize(output)
  super
  @output_hash = {
    metadata: metadata_hash,
    files:    [],
    summary:  { offense_count: 0 }
  }
end

def metadata_hash
  {
    rubocop_version: RuboCop::Version::STRING,
    ruby_engine:     RUBY_ENGINE,
    ruby_version:    RUBY_VERSION,
    ruby_patchlevel: RUBY_PATCHLEVEL.to_s,
    ruby_platform:   RUBY_PLATFORM
  }
end

def started(target_files)
  output_hash[:summary][:target_file_count] = target_files.count
end