module HTTP::Chainable

def accept(type)
  with :accept => MimeType.normalize(type)
end

def auth(*args)
  value = case args.count
          when 1 then args.first
          when 2 then AuthorizationHeader.build(*args)
          else fail ArgumentError, "wrong number of arguments (#{args.count} for 1..2)"
          end
  with :authorization => value.to_s
end

def branch(options)
  HTTP::Client.new(options)
end

def connect(uri, options = {})
  request :connect, uri, options
end

def default_callbacks
  default_options.callbacks
end

def default_callbacks=(callbacks)
  @default_options = default_options.dup do |opts|
    opts.callbacks = callbacks
  end
end

def default_headers
  default_options.headers
end

def default_headers=(headers)
  @default_options = default_options.dup do |opts|
    opts.headers = headers
  end
end

def default_options
  @default_options ||= HTTP::Options.new
end

def default_options=(opts)
  @default_options = HTTP::Options.new(opts)
end

def delete(uri, options = {})
  request :delete, uri, options
end

def get(uri, options = {})
  request :get, uri, options
end

def head(uri, options = {})
  request :head, uri, options
end

def options(uri, options = {})
  request :options, uri, options
end

def patch(uri, options = {})
  request :patch, uri, options
end

def post(uri, options = {})
  request :post, uri, options
end

def put(uri, options = {})
  request :put, uri, options
end

def request(verb, uri, options = {})
  branch(options).request verb, uri
end

def stream
  with_response(:object)
end

def trace(uri, options = {})
  request :trace, uri, options
end

def via(*proxy)
  proxy_hash = {}
  proxy_hash[:proxy_address]  = proxy[0] if proxy[0].is_a?(String)
  proxy_hash[:proxy_port]     = proxy[1] if proxy[1].is_a?(Integer)
  proxy_hash[:proxy_username] = proxy[2] if proxy[2].is_a?(String)
  proxy_hash[:proxy_password] = proxy[3] if proxy[3].is_a?(String)
  if [2, 4].include?(proxy_hash.keys.size)
    branch default_options.with_proxy(proxy_hash)
  else
    fail(RequestError, "invalid HTTP proxy: #{proxy_hash}")
  end
end

def with_follow(follow)
  branch default_options.with_follow(follow)
end

def with_headers(headers)
  branch default_options.with_headers(headers)
end