ece517-p3/expertiza

# these 4 helpers consist of the list of plot options that are available for the graph type
module LineGraphHelper
  # development note
  # 1)method for generate the data packet has already been - completed: helpers/chart_helper.rb
  # 2)javascript for rendering the chart - partially completed
  #   currently value x axis can not be independently set
  # 3)data mining method for gathering data - partially completed
  #   there's always more to add
end

module BarChartHelper
end

module PieChartHelper
  # only for single object compaireson meaning
  # 1)method for generate the data packet has already been - completed: helpers/chart_helper.rb
  # 2)javascript for rendering the chart - completed

  # good for showing grade distributions
  # methods needed to convert the data gathered to useful way of displaying
end

module ScatterPlotHelper
  # 1)method for generate the data packet has already been - completed: helpers/chart_helper.rb
  # 2)javascript for rendering the chart - completed
end

module AnalyticHelper
  include ChartHelper
  #====== generic method to generate chart data (chart_type decides which chart to render) ================#
  def get_chart_data(chart_type, object_type, object_id_list, data_type_list)
    data_point = []
    object_model = Object.const_get(object_type.capitalize)
    object_id_list.each do |object_id|
      object = object_model.find(object_id)
      object_data = {}
      object_data[:name] = object.name
      object_data[:data] = gather_data(object, data_type_list)
      data_point << object_data
    end
    # Formatting the optional parameters field ( pie charts do not support optional parameters )
    if chart_type != "pie"
      option = {}
      option[:x_axis_categories] = data_type_list
    else
      option = nil
    end
    Chart.new(chart_type.to_sym, data_point, option).data
  end

  def gather_data(object, data_type_array)
    data_array = []
    data_type_array.each do |data_method|
      data_array << object.send(data_method)
    end
    data_array
  end

  #======== sorting ============#
  def sort_by_name(array_of_arrays)
    array_of_arrays.sort_by {|a| a[0] }
  end

  #======= helper data formatting =====#
  # TODO: implementing normalize for bar chart
  def normalize(array)
    normalized_array = []
    max = array.max
    array.each do |element|
      normalized_array << element.to_f / max
    end
    normalized_array
  end

  def distribution(array, num_intervals, x_min = array.min)
    distribution = []
    interval_size = ((array.max - x_min).to_f / num_intervals).ceil
    intervals = (1..num_intervals).to_a.collect {|val| val * interval_size }
    intervals.each do |interval_max|
      distribution << array.select {|a| a < interval_max }.count
      array.reject! {|a| a < interval_max }
    end
    distribution
  end

  def distribution_categories(array, num_intervals, x_min = array.min)
    categories = []
    interval_size = ((array.max - x_min).to_f / num_intervals).ceil
    intervals = (1..num_intervals).to_a.collect {|val| val * interval_size }
    interval_min = 0
    intervals.each do |interval_max|
      categories << (interval_min..interval_max).to_s
      interval_min = interval_max
    end
    categories
  end
end