class VCR::Cassette::Migrator

def denormalize_header_key(key)
  key.split('-').               # 'user-agent' => %w(user agent)
    each { |w| w.capitalize! }. # => %w(User Agent)
    join('-')
end

def denormalize_http_header_keys(object)
  object.headers = {}.tap do |denormalized|
    object.headers.each do |k, v|
      denormalized[denormalize_header_key(k)] = v
    end if object.headers
  end
end

def initialize(dir, out = $stdout)
  @dir, @out = dir, out
  @yaml_load_errors = yaml_load_errors
end

def load_yaml(cassette)
  if ::YAML.respond_to?(:unsafe_load_file)
    ::YAML.unsafe_load_file(cassette)
  else
    ::YAML.load_file(cassette)
  end
rescue *@yaml_load_errors
  return nil
end

def migrate!
  @out.puts "Migrating VCR cassettes in #{@dir}..."
  Dir["#{@dir}/**/*.yml"].each do |cassette|
    migrate_cassette(cassette)
  end
end

def migrate_cassette(cassette)
  unless http_interactions = load_yaml(cassette)
    @out.puts "  - Ignored #{relative_casssette_name(cassette)} since it could not be parsed as YAML (does it have some ERB?)"
    return
  end
  unless valid_vcr_1_cassette?(http_interactions)
    @out.puts "  - Ignored #{relative_casssette_name(cassette)} since it does not appear to be a valid VCR 1.x cassette"
    return
  end
  http_interactions.map! do |interaction|
    interaction.response.adapter_metadata = {}
    interaction.recorded_at = File.mtime(cassette)
    remove_unnecessary_standard_port(interaction)
    denormalize_http_header_keys(interaction.request)
    denormalize_http_header_keys(interaction.response)
    normalize_body(interaction.request)
    normalize_body(interaction.response)
    interaction.to_hash
  end
  hash = {
    "http_interactions" => http_interactions,
    "recorded_with"     => "VCR #{VCR.version}"
  }
  File.open(cassette, 'w') { |f| f.write ::YAML.dump(hash) }
  @out.puts "  - Migrated #{relative_casssette_name(cassette)}"
end

def normalize_body(object)
  object.body = EMPTY_STRING if object.body.nil?
end

def relative_casssette_name(cassette)
  cassette.gsub(%r|\A#{Regexp.escape(@dir)}/?|, '')
end

def remove_unnecessary_standard_port(interaction)
  uri = VCR.configuration.uri_parser.parse(interaction.request.uri)
  if uri.scheme == 'http'  && uri.port == 80 ||
     uri.scheme == 'https' && uri.port == 443
    uri.port = nil
    interaction.request.uri = uri.to_s
  end
rescue URI::InvalidURIError
  # ignore this URI.
  # This can occur when the user uses the filter_sensitive_data option
  # to put a substitution string in their URI
end

def valid_vcr_1_cassette?(content)
  content.is_a?(Array) &&
  content.map(&:class).uniq == [HTTPInteraction]
end

def yaml_load_errors
  [ArgumentError].tap do |errors|
    errors << Psych::SyntaxError if defined?(Psych::SyntaxError)
  end
end