# Module to apply QAQC checks to a model
module OpenstudioStandards
  module QAQC
    # @!group Service Water Heating

    # Checks the hot water use in a model for typical values
    #
    # @param category [String] category to bin this check into
    # @param target_standard [String] standard template, e.g. '90.1-2013'
    # @param min_pass_pct [Double] threshold for throwing an error for percent difference
    # @param max_pass_pct [Double] threshold for throwing an error for percent difference
    # @param name_only [Boolean] If true, only return the name of this check
    # @return [OpenStudio::Attribute] OpenStudio Attribute object containing check results
    def self.check_service_hot_water(category, target_standard, min_pass_pct: 0.25, max_pass_pct: 0.25, name_only: false)
      # @todo could expose meal turnover and people per unit for res and hotel into arguments

      # summary of the check
      check_elems = OpenStudio::AttributeVector.new
      check_elems << OpenStudio::Attribute.new('name', 'Domestic Hot Water')
      check_elems << OpenStudio::Attribute.new('category', category)
      if target_standard == 'ICC IECC 2015'
        check_elems << OpenStudio::Attribute.new('description', 'Check service water heating consumption against Table R405.5.2(1) in ICC IECC 2015 Residential Provisions.')
      else
        check_elems << OpenStudio::Attribute.new('description', 'Check against the 2011 ASHRAE Handbook - HVAC Applications, Table 7 section 50.14.')
      end

      # stop here if only name is requested this is used to populate display name for arguments
      if name_only == true
        results = []
        check_elems.each do |elem|
          results << elem.valueAsString
        end
        return results
      end

      std = Standard.build(target_standard)

      begin
        # loop through water_use_equipment
        service_water_consumption_daily_avg_gal = 0.0
        @model.getWaterUseEquipments.each do |water_use_equipment|
          # get peak flow rate from def
          peak_flow_rate_si = water_use_equipment.waterUseEquipmentDefinition.peakFlowRate
          source_units = 'm^3/s'
          target_units = 'gal/min'
          peak_flow_rate_ip = OpenStudio.convert(peak_flow_rate_si, source_units, target_units).get

          # get value from flow rate schedule
          if water_use_equipment.flowRateFractionSchedule.is_initialized
            # get annual equiv for model schedule
            schedule_inst = water_use_equipment.flowRateFractionSchedule.get
            annual_equiv_flow_rate = OpenstudioStandards::Schedules.schedule_get_equivalent_full_load_hours(schedule_inst)
            if annual_equiv_flow_rate.nil?
              check_elems << OpenStudio::Attribute.new('flag', "#{schedule_inst.name} isn't a Ruleset or Constant schedule. Can't calculate annual equivalent full load hours.")
              next
            end
          else
            # issue flag
            check_elems << OpenStudio::Attribute.new('flag', "#{water_use_equipment.name} doesn't have a schedule. Can't identify hot water consumption.")
            next
          end

          # add to global service water consumpiton value
          service_water_consumption_daily_avg_gal += 60.0 * peak_flow_rate_ip * annual_equiv_flow_rate / 365.0
        end

        if target_standard == 'ICC IECC 2015'

          num_people = 0.0
          @model.getSpaceTypes.each do |space_type|
            next if !space_type.standardsSpaceType.is_initialized
            next if space_type.standardsSpaceType.get != 'Apartment' # currently only supports midrise apt space type

            space_type_floor_area = space_type.floorArea
            space_type_num_people = space_type.getNumberOfPeople(space_type_floor_area)
            num_people += space_type_num_people
          end

          # lookup target gal/day for the building
          bedrooms_per_unit = 2.0 # assumption
          num_units = num_people / 2.5 # Avg 2.5 units per person.
          target_consumption = std.model_find_icc_iecc_2015_hot_water_demand(@model, num_units, bedrooms_per_unit)
        else
          # only other path for now is 90.1-2013

          # get building type
          building_type = ''
          if @model.getBuilding.standardsBuildingType.is_initialized
            building_type = @model.getBuilding.standardsBuildingType.get
          end

          # lookup data from standards
          ashrae_hot_water_demand = std.model_find_ashrae_hot_water_demand(@model)

          # building type specific logic for water consumption
          # todo - update test to exercise various building types
          if !ashrae_hot_water_demand.empty?

            if building_type == 'FullServiceRestaurant'
              num_people_hours = 0.0
              @model.getSpaceTypes.each do |space_type|
                next if !space_type.standardsSpaceType.is_initialized
                next if space_type.standardsSpaceType.get != 'Dining'

                space_type_floor_area = space_type.floorArea

                space_type_num_people_hours = 0.0
                # loop through peole instances
                space_type.peoples.each do |inst|
                  inst_num_people = inst.getNumberOfPeople(space_type_floor_area)
                  inst_schedule = inst.numberofPeopleSchedule.get # sim will fail prior to this if doesn't have it
                  annual_equivalent_people = OpenstudioStandards::Schedules.schedule_get_equivalent_full_load_hours(inst_schedule)
                  if annual_equivalent_people.nil?
                    check_elems << OpenStudio::Attribute.new('flag', "#{inst_schedule.name} isn't a Ruleset or Constant schedule. Can't calculate annual equivalent full load hours.")
                    annual_equivalent_people = 0.0
                  end
                  inst_num_people_hours = annual_equivalent_people * inst_num_people
                  space_type_num_people_hours += inst_num_people_hours
                end

                num_people_hours += space_type_num_people_hours
              end
              num_meals = num_people_hours / 365.0 * 1.5 # 90 minute meal
              target_consumption = num_meals * ashrae_hot_water_demand.first[:avg_day_unit]

            elsif ['LargeHotel', 'SmallHotel'].include? building_type
              num_people = 0.0
              @model.getSpaceTypes.each do |space_type|
                next if !space_type.standardsSpaceType.is_initialized
                next if space_type.standardsSpaceType.get != 'GuestRoom'

                space_type_floor_area = space_type.floorArea
                space_type_num_people = space_type.getNumberOfPeople(space_type_floor_area)
                num_people += space_type_num_people
              end

              # find best fit from returned results
              num_units = num_people / 2.0 # 2 people per room design load, not typical occupancy
              avg_day_unit = nil
              fit = nil
              ashrae_hot_water_demand.each do |block|
                if fit.nil?
                  avg_day_unit = block[:avg_day_unit]
                  fit = (avg_day_unit - block[:block]).abs
                elsif (avg_day_unit - block[:block]).abs - fit
                  avg_day_unit = block[:avg_day_unit]
                  fit = (avg_day_unit - block[:block]).abs
                end
              end
              target_consumption = num_units * avg_day_unit

            elsif building_type == 'MidriseApartment'
              num_people = 0.0
              @model.getSpaceTypes.each do |space_type|
                next if !space_type.standardsSpaceType.is_initialized
                next if space_type.standardsSpaceType.get != 'Apartment'

                space_type_floor_area = space_type.floorArea
                space_type_num_people = space_type.getNumberOfPeople(space_type_floor_area)
                num_people += space_type_num_people
              end

              # find best fit from returned results
              num_units = num_people / 2.5 # Avg 2.5 units per person.
              avg_day_unit = nil
              fit = nil
              ashrae_hot_water_demand.each do |block|
                if fit.nil?
                  avg_day_unit = block[:avg_day_unit]
                  fit = (avg_day_unit - block[:block]).abs
                elsif (avg_day_unit - block[:block]).abs - fit
                  avg_day_unit = block[:avg_day_unit]
                  fit = (avg_day_unit - block[:block]).abs
                end
              end
              target_consumption = num_units * avg_day_unit

            elsif ['Office', 'LargeOffice', 'MediumOffice', 'SmallOffice'].include? building_type
              num_people = @model.getBuilding.numberOfPeople
              target_consumption = num_people * ashrae_hot_water_demand.first[:avg_day_unit]
            elsif building_type == 'PrimarySchool'
              num_people = 0.0
              @model.getSpaceTypes.each do |space_type|
                next if !space_type.standardsSpaceType.is_initialized
                next if space_type.standardsSpaceType.get != 'Classroom'

                space_type_floor_area = space_type.floorArea
                space_type_num_people = space_type.getNumberOfPeople(space_type_floor_area)
                num_people += space_type_num_people
              end
              target_consumption = num_people * ashrae_hot_water_demand.first[:avg_day_unit]
            elsif building_type == 'QuickServiceRestaurant'
              num_people_hours = 0.0
              @model.getSpaceTypes.each do |space_type|
                next if !space_type.standardsSpaceType.is_initialized
                next if space_type.standardsSpaceType.get != 'Dining'

                space_type_floor_area = space_type.floorArea

                space_type_num_people_hours = 0.0
                # loop through peole instances
                space_type.peoples.each do |inst|
                  inst_num_people = inst.getNumberOfPeople(space_type_floor_area)
                  inst_schedule = inst.numberofPeopleSchedule.get # sim will fail prior to this if doesn't have it
                  annual_equivalent_people = OpenstudioStandards::Schedules.schedule_get_equivalent_full_load_hours(inst_schedule)
                  if annual_equivalent_people.nil?
                    check_elems << OpenStudio::Attribute.new('flag', "#{inst_schedule.name} isn't a Ruleset or Constant schedule. Can't calculate annual equivalent full load hours.")
                    annual_equivalent_people = 0.0
                  end
                  inst_num_people_hours = annual_equivalent_people * inst_num_people
                  space_type_num_people_hours += inst_num_people_hours
                end

                num_people_hours += space_type_num_people_hours
              end
              num_meals = num_people_hours / 365.0 * 0.5 # 30 minute leal
              # todo - add logic to address drive through traffic
              target_consumption = num_meals * ashrae_hot_water_demand.first[:avg_day_unit]

            elsif building_type == 'SecondarySchool'
              num_people = 0.0
              @model.getSpaceTypes.each do |space_type|
                next if !space_type.standardsSpaceType.is_initialized
                next if space_type.standardsSpaceType.get != 'Classroom'

                space_type_floor_area = space_type.floorArea
                space_type_num_people = space_type.getNumberOfPeople(space_type_floor_area)
                num_people += space_type_num_people
              end
              target_consumption = num_people * ashrae_hot_water_demand.first[:avg_day_unit]
            else
              check_elems << OpenStudio::Attribute.new('flag', "No rule of thumb values exist for  #{building_type}. Hot water consumption was not checked.")
            end

          else
            check_elems << OpenStudio::Attribute.new('flag', "No rule of thumb values exist for  #{building_type}. Hot water consumption was not checked.")
          end
        end

        # check actual against target
        if service_water_consumption_daily_avg_gal < target_consumption * (1.0 - min_pass_pct)
          check_elems <<  OpenStudio::Attribute.new('flag', "Annual average of #{service_water_consumption_daily_avg_gal.round} gallons per day of hot water is more than #{min_pass_pct * 100} % below the expected value of #{target_consumption.round} gallons per day.")
        elsif service_water_consumption_daily_avg_gal > target_consumption * (1.0 + max_pass_pct)
          check_elems <<  OpenStudio::Attribute.new('flag', "Annual average of #{service_water_consumption_daily_avg_gal.round} gallons per day of hot water is more than #{max_pass_pct * 100} % above the expected value of #{target_consumption.round} gallons per day.")
        end
      rescue StandardError => e
        # brief description of ruby error
        check_elems << OpenStudio::Attribute.new('flag', "Error prevented QAQC check from running (#{e}).")

        # backtrace of ruby error for diagnostic use
        if @error_backtrace then check_elems << OpenStudio::Attribute.new('flag', e.backtrace.join("\n").to_s) end
      end

      # add check_elms to new attribute
      check_elem = OpenStudio::Attribute.new('check', check_elems)

      return check_elem
    end
  end
end