web/stores/select-rate/helper.ts

import { AvailabilityEnum } from "@/types/components/hotelReservation/selectHotel/selectHotel"
import {
  RoomPackageCodeEnum,
  type RoomPackages,
} from "@/types/components/hotelReservation/selectRate/roomFilter"
import type {
  Rate,
  RateCode,
} from "@/types/components/hotelReservation/selectRate/selectRate"
import type { RoomConfiguration } from "@/types/trpc/routers/hotel/roomAvailability"

interface CalculateRoomSummaryParams {
  availablePackages: RoomPackages
  getFilteredRooms: (roomIndex: number) => RoomConfiguration[]
  roomCategories: Array<{ name: string; roomTypes: Array<{ code: string }> }>
  selectedPackagesByRoom: Record<number, RoomPackageCodeEnum[]>
  selectedRate: RateCode
  roomIndex: number
}

export function calculateRoomSummary({
  selectedRate,
  roomIndex,
  getFilteredRooms,
  availablePackages,
  roomCategories,
  selectedPackagesByRoom,
}: CalculateRoomSummaryParams): Rate | null {
  const filteredRooms = getFilteredRooms(roomIndex)
  const selectedPackages = selectedPackagesByRoom[roomIndex] || []

  const room = filteredRooms.find(
    (room) => room.roomTypeCode === selectedRate.roomTypeCode
  )
  if (!room) return null

  const product = room.products.find(
    (product) =>
      product.productType.public.rateCode === selectedRate.publicRateCode
  )
  if (!product) return null

  const petRoomPackage = selectedPackages.includes(RoomPackageCodeEnum.PET_ROOM)
    ? availablePackages.find((pkg) => pkg.code === RoomPackageCodeEnum.PET_ROOM)
    : undefined

  const features = filteredRooms.find((room) =>
    room.features.some(
      (feature) => feature.code === RoomPackageCodeEnum.PET_ROOM
    )
  )?.features

  const roomType = roomCategories.find((roomCategory) =>
    roomCategory.roomTypes.some((type) => type.code === room.roomTypeCode)
  )

  return {
    features: petRoomPackage && features ? features : [],
    priceName: selectedRate.name,
    priceTerm: selectedRate.paymentTerm,
    public: product.productType.public,
    member: product.productType.member,
    roomType: roomType?.name ?? room.roomType,
    roomTypeCode: room.roomTypeCode,
  }
}

/**
 * Get the lowest priced room for each room type that appears more than once.
 */

export function filterDuplicateRoomTypesByLowestPrice(
  roomConfigurations: RoomConfiguration[]
): RoomConfiguration[] {
  const roomTypeCount = roomConfigurations.reduce<Record<string, number>>(
    (roomTypeTally, currentRoom) => {
      const currentRoomType = currentRoom.roomType
      const currentCount = roomTypeTally[currentRoomType] || 0

      return {
        ...roomTypeTally,
        [currentRoomType]: currentCount + 1,
      }
    },
    {}
  )

  const duplicateRoomTypes = new Set(
    Object.keys(roomTypeCount).filter((roomType) => roomTypeCount[roomType] > 1)
  )

  const roomMap = new Map()

  roomConfigurations.forEach((room) => {
    const { roomType, products, status } = room

    if (!duplicateRoomTypes.has(roomType)) {
      roomMap.set(roomType, room)
      return
    }

    const previousRoom = roomMap.get(roomType)

    // Prioritize 'Available' status
    if (
      status === AvailabilityEnum.Available &&
      previousRoom?.status === AvailabilityEnum.NotAvailable
    ) {
      roomMap.set(roomType, room)
      return
    }

    if (
      status === AvailabilityEnum.NotAvailable &&
      previousRoom?.status === AvailabilityEnum.Available
    ) {
      return
    }

    if (previousRoom) {
      products.forEach((product) => {
        const { productType } = product
        const publicProduct = productType.public || {
          requestedPrice: null,
          localPrice: null,
        }
        const memberProduct = productType.member || {
          requestedPrice: null,
          localPrice: null,
        }

        const {
          requestedPrice: publicRequestedPrice,
          localPrice: publicLocalPrice,
        } = publicProduct
        const {
          requestedPrice: memberRequestedPrice,
          localPrice: memberLocalPrice,
        } = memberProduct

        const previousLowest = roomMap.get(roomType)

        const currentRequestedPrice = Math.min(
          Number(publicRequestedPrice?.pricePerNight) ?? Infinity,
          Number(memberRequestedPrice?.pricePerNight) ?? Infinity
        )
        const currentLocalPrice = Math.min(
          Number(publicLocalPrice?.pricePerNight) ?? Infinity,
          Number(memberLocalPrice?.pricePerNight) ?? Infinity
        )

        if (
          !previousLowest ||
          currentRequestedPrice <
            Math.min(
              Number(
                previousLowest.products[0].productType.public.requestedPrice
                  ?.pricePerNight
              ) ?? Infinity,
              Number(
                previousLowest.products[0].productType.member?.requestedPrice
                  ?.pricePerNight
              ) ?? Infinity
            ) ||
          (currentRequestedPrice ===
            Math.min(
              Number(
                previousLowest.products[0].productType.public.requestedPrice
                  ?.pricePerNight
              ) ?? Infinity,
              Number(
                previousLowest.products[0].productType.member?.requestedPrice
                  ?.pricePerNight
              ) ?? Infinity
            ) &&
            currentLocalPrice <
              Math.min(
                Number(
                  previousLowest.products[0].productType.public.localPrice
                    ?.pricePerNight
                ) ?? Infinity,
                Number(
                  previousLowest.products[0].productType.member?.localPrice
                    ?.pricePerNight
                ) ?? Infinity
              ))
        ) {
          roomMap.set(roomType, room)
        }
      })
    } else {
      roomMap.set(roomType, room)
    }
  })

  return Array.from(roomMap.values())
}