class Excon::Connection

def setup_proxy
  if @data[:disable_proxy]
    if @data[:proxy]
      raise ArgumentError, "`:disable_proxy` parameter and `:proxy` parameter cannot both be set at the same time."
    end
    return
  end
  return if @data[:scheme] == UNIX
  proxy_from_env
  case @data[:proxy]
  when nil
    @data.delete(:proxy)
  when ''
    @data.delete(:proxy)
  when Hash
    # no processing needed
  when String, URI
    uri = @data[:proxy].is_a?(String) ? URI.parse(@data[:proxy]) : @data[:proxy]
    @data[:proxy] = {
      :host       => uri.host,
      :hostname   => uri.hostname,
      # path is only sensible for a Unix socket proxy
      :path       => uri.scheme == UNIX ? uri.path : nil,
      :port       => uri.port,
      :scheme     => uri.scheme,
    }
    if uri.password
      @data[:proxy][:password] = uri.password
    end
    if uri.user
      @data[:proxy][:user] = uri.user
    end
    if @data[:ssl_proxy_headers] && !@data[:ssl_uri_schemes].include?(@data[:scheme])
      raise ArgumentError, "The `:ssl_proxy_headers` parameter should only be used with HTTPS requests."
    end
    if @data[:proxy][:scheme] == UNIX
      if @data[:proxy][:host]
        raise ArgumentError, "The `:host` parameter should not be set for `unix://` proxies.\n" +
                             "When supplying a `unix://` URI, it should start with `unix:/` or `unix:///`."
      end
    else
      unless uri.host && uri.port && uri.scheme
        raise Excon::Errors::ProxyParse, "Proxy is invalid"
      end
    end
  else
    raise Excon::Errors::ProxyParse, "Proxy is invalid"
  end
  if @data.has_key?(:proxy) && @data[:scheme] == 'http'
    @data[:headers]['Proxy-Connection'] ||= 'Keep-Alive'
    # https credentials happen in handshake
    if @data[:proxy].has_key?(:user) || @data[:proxy].has_key?(:password)
      user, pass = Utils.unescape_form(@data[:proxy][:user].to_s), Utils.unescape_form(@data[:proxy][:password].to_s)
      auth = ["#{user}:#{pass}"].pack('m').delete(Excon::CR_NL)
      @data[:headers]['Proxy-Authorization'] = 'Basic ' + auth
    end
  end
end