planned_simulation.rb

  def self.generate_planned_simulation(model_package_id, start_date, finish_date, increment)
    start_date = Date.strptime(start_date,'%B %d, %Y')
    finish_date = Date.strptime(finish_date, '%B %d, %Y')

    dates = get_dates_with_interval(start_date, finish_date, increment)
    activities = Activity.all(
      :conditions => [
        '(start_date <= :finish_date OR finish_date <= :finish_date) AND model_package_id = :model_package_id',
        { :finish_date => finish_date, :model_package_id => model_package_id }
      ],
      :include => [:equipment_items, :work_status]
    )

    simulation_data = Array.new

    last_date = activities.map{|a| [a.start_date, a.finish_date] }.flatten.compact.uniq.sort.first || Date.parse("1970-01-01")

    dates.each do |d|
      date_data = Hash.new
      cad_ids_collection = []

      interval_dates = ((last_date + 1)..d).to_a.reverse

      interval_dates.each do |date|

        segmented_activities = activities.find_all{|a| (a.start_date == date) or (a.finish_date == date) }

        segmented_activities.each do |a|
          equipment_item_ids = a.equipment_items.map{|ei| 
            ei.cad_id unless cad_ids_collection.include?(ei.cad_id)
          }.compact
          cad_ids_collection += equipment_item_ids

          if a.finish_date == date
            suffix = "_finish"
          else
            suffix = "_start"
          end

          name = a.work_status.id.to_s + suffix
          date_data[name] ||= []
          date_data[name] += equipment_item_ids.to_a
        end
      end

      unless date_data.size == 0
        date_data.delete_if{|key, value| value.blank? }
        simulation_data << {:date => d, :materials => date_data}
      end

      last_date = d
    end
    simulation_data.delete_if{|e| e[:materials].blank? }

    return simulation_data
  end