class ActiveFedora::SolrService

def self.construct_query_for_pids(pid_array)
  query = ""
  pid_array.each_index do |i|
    query << "#{SOLR_DOCUMENT_ID}:#{escape_uri_for_query(pid_array[i])}"
    query << " OR " if i != pid_array.length-1
  end
  query = "id:NEVER_USE_THIS_ID" if query.empty? || query == "id:"
  return query
end

def self.escape_uri_for_query(uri)
  return uri.gsub(/(:)/, '\\:')
end

def self.instance
  raise SolrNotInitialized unless Thread.current[:solr_service]
  Thread.current[:solr_service]
end

def self.load_mappings( config_path=nil )
  if config_path.nil? 
    if defined?(RAILS_ROOT)
      config_path = File.join(RAILS_ROOT, "config", "solr_mappings.yml")
    end
    # Default to using the config file within the gem 
    if !File.exist?(config_path.to_s)
      config_path = File.join(File.dirname(__FILE__), "..", "..", "config", "solr_mappings.yml")          
    end
  end
  logger.info("FEDORA: loading SolrService mappings from #{File.expand_path(config_path)}")
  @@mappings = YAML::load(File.open(config_path))
  
  mappings["id"] = "id" unless mappings["id"]
end

def self.logger      
  @logger ||= defined?(RAILS_DEFAULT_LOGGER) ? RAILS_DEFAULT_LOGGER : Logger.new(STDOUT)
end

def self.mappings
  @@mappings
end

def self.mappings=(mappings)
  @@mappings = mappings
end    

def self.register(host=nil, args={})
  Thread.current[:solr_service]=self.new(host, args)
end

def self.reify_solr_results(solr_result)
  unless solr_result.is_a?(Solr::Response::Standard)
    raise ArgumentError.new("Only solr responses (Solr::Response::Standard) are allowed. You provided a #{solr_result.class}")
  end
  results = []
  solr_result.hits.each do |hit|
    model_value = hit["active_fedora_model_s"].first
    if model_value.include?("::")
      classname = eval(model_value)
    else
      classname = Kernel.const_get(model_value)
    end
    results << Fedora::Repository.instance.find_model(hit[SOLR_DOCUMENT_ID], classname)
  end
  return results
end

def initialize(host, args)
  host = 'http://localhost:8080/solr' unless host
  opts = {:autocommit=>:on}.merge(args)
  @conn = Solr::Connection.new(host, opts)
end