module Sunbro
  class DynamicHTTP

    attr_reader :session

    def initialize(opts = {})
      @opts = opts
      Retryable.retryable { new_session }
    end

    def close
      @session.driver.quit
    rescue IOError
      nil
    end

    def new_session
      Capybara.register_driver :poltergeist do |app|
        Capybara::Poltergeist::Driver.new(
          app,
          timeout: 10,
          js_errors: false,
          phantomjs_options: phantomjs_options,
        )
      end
      Capybara.default_driver = :poltergeist
      Capybara.javascript_driver = :poltergeist
      Capybara.run_server = false
      @session = Capybara::Session.new(:poltergeist)
      @session.driver.headers = {
        'User-Agent' => user_agent
      }
      @session
    end

    def phantomjs_options
      @phantomjs_options ||= begin
        opts = [ '--load-images=no', '--ignore-ssl-errors=yes' ]
        if Sunbro::Settings.proxy_host
          if Sunbro::Settings.proxy_port
            opts << "--proxy=#{Sunbro::Settings.proxy_host}:#{Sunbro::Settings.proxy_port}"
          else
            opts << "--proxy=#{Sunbro::Settings.proxy_host}"
          end
        end
        opts
      end
    end

    def user_agent
      @opts[:agent] || Settings.phantomjs_user_agent
    end

    def restart_session
      close
      Retryable.retryable { new_session }
    end

    #
    # Create new Pages from the response of an HTTP request to *url*,
    # including redirects
    #
    def fetch_page(url, opts={})
      begin
        tries ||= 5
        get_page(url, opts)
      rescue IOError, Capybara::Poltergeist::DeadClient, Errno::EPIPE, NoMethodError, Capybara::Poltergeist::BrowserError => e
        restart_session
        retry unless (tries -= 1).zero?
        close
        raise e
      end
    end

    def get_page(url, opts)
      reset = opts.fetch(:reset) rescue true
      session.visit(url.to_s)
      page = create_page_from_session(url, session, opts)
      session.reset! if reset
      page
    rescue Capybara::Poltergeist::TimeoutError => e
      restart_session
      return Page.new(url, :error => e)
    end

    private

    def create_page_from_session(url, session, opts)
      url = url.to_s
      if url == session.current_url
        Page.new(
            session.current_url,
            :body => session.html.dup,
            :code => session.status_code,
            :headers => session.response_headers,
            :force_format => (opts[:force_format] || default_page_format)
        )
      else
        Page.new(
            session.current_url,
            :body => session.html.dup,
            :code => 301,
            :redirect_from => url,
            :headers => session.response_headers,
            :force_format => (opts[:force_format] || default_page_format)
        )
      end
    end

    def default_page_format
      # Don't force the page format if the default format is set to :any
      return unless [:xml, :html].include? Settings.page_format
      Settings.page_format
    end

  end
end