module Beaker
  module DSL
    module Helpers
      # Convenience methods for checking links and moving web content to hosts
      module WebHelpers
        # Blocks until the port is open on the host specified, returns false
        # on failure
        def port_open_within?(host, port = 8140, seconds = 120)
          repeat_for(seconds) do
            host.port_open?(port)
          end
        end

        # Determine is a given URL is accessible
        # @param [String] link The URL to examine
        # @param [Integer] limit redirect limit, will follow redirects that many times
        # @return [Boolean] true if the ultimate URL after following redirects (301&302) has a '200' HTTP response code, false otherwise
        # @example
        #  extension = link_exists?("#{URL}.tar.gz") ? ".tar.gz" : ".tar"
        def link_exists?(link, limit = 10)
          begin
            require "net/http"
            require "net/https"
            require "open-uri"
            url = URI.parse(link)
            http = Net::HTTP.new(url.host, url.port)
            http.use_ssl = (url.scheme == 'https')
            http.verify_mode = (OpenSSL::SSL::VERIFY_NONE)
            response = http.start { |http| http.head(url.request_uri) }
            if (%w[301 302].include? response.code) && limit > 0
              logger.debug("#{__method__} following #{response.code} to #{response['location']}")
              link_exists?(response['location'], limit - 1)
            else
              response.code == "200"
            end
          rescue
            return false
          end
        end

        # Fetch file_name from the given base_url into dst_dir.
        #
        # @param [String] base_url The base url from which to recursively download
        #                          files.
        # @param [String] file_name The trailing name component of both the source url
        #                           and the destination file.
        # @param [String] dst_dir The local destination directory.
        #
        # @return [String] dst The name of the newly-created file.
        #
        # @!visibility private
        def fetch_http_file(base_url, file_name, dst_dir)
          require 'open-uri'
          FileUtils.makedirs(dst_dir)
          base_url.chomp!('/')
          src = "#{base_url}/#{file_name}"
          dst = File.join(dst_dir, file_name)
          if options[:cache_files_locally] && File.exist?(dst)
            logger.notify "Already fetched #{dst}"
          else
            logger.notify "Fetching: #{src}"
            logger.notify "  and saving to #{dst}"
            begin
              URI.open(src) do |remote|
                File.open(dst, "w") do |file|
                  FileUtils.copy_stream(remote, file)
                end
              end
            rescue OpenURI::HTTPError => e
              raise "Failed to fetch_remote_file '#{src}' (#{e.message})" if /404.*/.match?(e.message)

              raise e
            end
          end
          return dst
        end

        # Recursively fetch the contents of the given http url, ignoring
        # `index.html` and `*.gif` files.
        #
        # @param [String] url The base http url from which to recursively download
        #                     files.
        # @param [String] dst_dir The local destination directory.
        #
        # @return [String] dst The name of the newly-created subdirectory of
        #                      dst_dir.
        #
        # @!visibility private
        def fetch_http_dir(url, dst_dir)
          logger.notify "fetch_http_dir (url: #{url}, dst_dir #{dst_dir})"
          url += '/' if !url.end_with?('/')
          url = URI.parse(url)
          chunks = url.path.split('/')
          dst = File.join(dst_dir, chunks.last)
          # determine directory structure to cut
          # only want to keep the last directory, thus cut total number of dirs - 2 (hostname + last dir name)
          cut = chunks.length - 2
          wget_command = "wget -nv -P #{dst_dir} --reject \"index.html*\",\"*.gif\" --cut-dirs=#{cut} -np -nH --no-check-certificate -r #{url}"

          logger.notify "Fetching remote directory: #{url}"
          logger.notify "  and saving to #{dst}"
          logger.notify "  using command: #{wget_command}"

          stdout_and_stderr_str, status = Open3.capture2e(wget_command)
          stdout_and_stderr_str.each_line do |line|
            logger.debug(line)
          end
          raise "Failed to fetch_remote_dir '#{url}' (exit code #{$?})" unless status.success?

          dst
        end
      end
    end
  end
end