# -*- encoding: utf-8 -*-

# Namespace for failover related URI classes.
module OnStomp::Failover::URI
  # A URI class for representing URIs with a 'failover' scheme.
  # We don't need to worry about hooking into Ruby's URI parsing jazz since
  # we have full control over when failover URIs will be created.
  class FAILOVER < OnStomp::Components::URI::STOMP
    # Matches a failover URI string, grouping the list of real URIs and
    # any query parameters for the failover URI.
    FAILOVER_REG = /^failover:(?:\/\/)?\(?([^\)]+)\)?(?:\?(.*))?/
    
    attr_reader :failover_uris
    def initialize uris, query
      @failover_uris = uris.map do |u|
        u.is_a?(::URI) ? u : ::URI.parse(u.strip)
      end
      super 'failover', nil, nil, nil, nil, '', "(#{uris.join(',')})", query, nil
    end
    
    # Converts a failover URI into a string. Ruby's Generic URIs don't seem
    # to allow mixing opaques and queries.
    # @return [String]
    def to_s
      base = "#{scheme}:#{opaque}"
      query.nil? || query.empty? ? base : "#{base}?#{query}"
    end
    
    class << self
      # Parses a failover URI string or an array of URIs into a
      # {OnStomp::Failover::URI::FAILOVER} object. Ruby's URI parser works
      # fine with +failover:(uri1,uri2,..)?params=..+ style URIs, but chokes
      # on +failover://uri1,uri2,..+ forms. This method gives us a bit more
      # flexibility.
      # @note If you are using the +open-uri+ extension with `failover`, you
      #   MUST use the +failover:(uri1,uri2,..)+ form because +open-uri+
      #   relies on +URI.parse+ to convert strings into `URI` objects.
      # @overload parse(str)
      #   @param [String] str
      #   @return [FAILOVER]
      # @overload parse(uri_arr)
      #   @param [Array<String or URI>] uri_arr
      #   @return [FAILOVER]
      def parse uri_str
        if uri_str.is_a? Array
          self.new uri_str, nil
        elsif uri_str =~ FAILOVER_REG
          self.new $1.split(','), $2
        else
          raise OnStomp::Failover::InvalidFailoverURIError, uri_str
        end
      end
    end
  end
end

module ::URI
  @@schemes['FAILOVER'] = OnStomp::Failover::URI::FAILOVER
end