# Get list of feature_selection algorithms
#
# @return [text/uri-list] URIs of feature_selection algorithms
get '/feature_selection/?' do
  list = [ url_for('/feature_selection/rfe', :full) ].join("\n") + "\n"
  case request.env['HTTP_ACCEPT']
  when /text\/html/
    content_type "text/html"
    OpenTox.text_to_html list
  else
    content_type 'text/uri-list'
    list
  end
end

# Get RDF/XML representation of feature_selection rfe algorithm
# @return [application/rdf+xml] OWL-DL representation of feature_selection rfe algorithm
get "/feature_selection/rfe/?" do
  algorithm = OpenTox::Algorithm::Generic.new(url_for('/feature_selection/rfe',:full))
  algorithm.metadata = {
    DC.title => 'recursive feature elimination',
    DC.creator => "andreas@maunz.de, helma@in-silico.ch",
    DC.contributor => "vorgrimmlerdavid@gmx.de",
    BO.instanceOf => "http://opentox.org/ontology/ist-algorithms.owl#feature_selection_rfe",
    RDF.type => [OT.Algorithm,OTA.PatternMiningSupervised],
    OT.parameters => [
      { DC.description => "Dataset URI", OT.paramScope => "mandatory", DC.title => "dataset_uri" },
      { DC.description => "Prediction Feature URI", OT.paramScope => "mandatory", DC.title => "prediction_feature_uri" },
      { DC.description => "Feature Dataset URI", OT.paramScope => "mandatory", DC.title => "feature_dataset_uri" },
      { DC.description => "Delete Instances with missing values", OT.paramScope => "optional", DC.title => "del_missing" }
  ]
  }
  case request.env['HTTP_ACCEPT']
  when /text\/html/
    content_type "text/html"
    OpenTox.text_to_html algorithm.to_yaml
  when /application\/x-yaml/
    content_type "application/x-yaml"
    algorithm.to_yaml
  else
    response['Content-Type'] = 'application/rdf+xml'  
    algorithm.to_rdfxml
  end
end

# Run rfe algorithm on dataset
#
# @param [String] dataset_uri URI of the training dataset
# @param [String] feature_dataset_uri URI of the feature dataset
# @return [text/uri-list] Task URI
post '/feature_selection/rfe/?' do 

  raise OpenTox::NotFoundError.new "Please submit a dataset_uri." unless params[:dataset_uri]
  raise OpenTox::NotFoundError.new "Please submit a prediction_feature_uri." unless params[:prediction_feature_uri]
  raise OpenTox::NotFoundError.new "Please submit a feature_dataset_uri." unless params[:feature_dataset_uri]

  ds_csv=OpenTox::RestClientWrapper.get( params[:dataset_uri], {:accept => "text/csv"} )
  tf_ds=Tempfile.open(['rfe_', '.csv'])
  tf_ds.puts(ds_csv)
  tf_ds.flush()

  prediction_feature = URI.escape(params[:prediction_feature_uri].split('/').last) # get col name
  
  fds_csv=OpenTox::RestClientWrapper.get( params[:feature_dataset_uri], {:accept => "text/csv"})
  tf_fds=Tempfile.open(['rfe_', '.csv'])
  tf_fds.puts(fds_csv)
  tf_fds.flush()

  del_missing = params[:del_missing] == "true" ? true : false

  task = OpenTox::Task.create("Recursive Feature Elimination", url_for('/feature_selection',:full)) do |task|
    r_result_file = OpenTox::Algorithm::FeatureSelection.rfe( { :ds_csv_file => tf_ds.path, :prediction_feature => prediction_feature, :fds_csv_file => tf_fds.path, :del_missing => del_missing } )
    r_result_uri = OpenTox::Dataset.create_from_csv_file(r_result_file).uri
    begin
      tf_ds.close!; tf_fds.close! 
      File.unlink(r_result_file)
    rescue
    end
    r_result_uri
  end
  response['Content-Type'] = 'text/uri-list'
  raise OpenTox::ServiceUnavailableError.newtask.uri+"\n" if task.status == "Cancelled"
  halt 202,task.uri.to_s+"\n"
end