import { z } from "zod"

import { getCacheClient } from "@scandic-hotels/common/dataCache"
import { createLogger } from "@scandic-hotels/common/logger/createLogger"

import * as api from "../../../api"
import { extractResponseDetails, serverErrorByStatus } from "../../../errors"
import { toApiLang } from "../../../utils"
import { locationCitySchema } from "../schemas/location/city"
import { locationHotelSchema } from "../schemas/location/hotel"

import type { Country } from "@scandic-hotels/common/constants/country"
import type { Lang } from "@scandic-hotels/common/constants/language"

const hotelUtilsLogger = createLogger("getLocationsByCountries")

type CitiesNamesByCountry = Record<
  Country | (string & {}),
  Array<{ name: string }>
> | null
type Hotel = Extract<
  z.infer<typeof locationsSchema>["data"][number],
  { type: "hotels" }
>
type City = Extract<
  z.infer<typeof locationsSchema>["data"][number],
  { type: "cities" }
>

export async function getLocationsByCountries({
  lang,
  citiesByCountry,
  serviceToken,
}: {
  lang: Lang
  citiesByCountry: CitiesNamesByCountry | null
  serviceToken: string
}) {
  const cacheClient = await getCacheClient()
  const countryKeys = Object.keys(citiesByCountry ?? {})
  let cacheKey = `${lang}:locations`

  if (countryKeys.length > 0) {
    cacheKey += `:${countryKeys.toSorted().join(",")}`
  }

  return await cacheClient.cacheOrGet(
    cacheKey.toLowerCase(),
    async () => {
      const apiResponse = await api.get(
        api.endpoints.v1.Hotel.locations,
        {
          headers: {
            Authorization: `Bearer ${serviceToken}`,
          },
        },
        {
          language: toApiLang(lang),
        }
      )

      if (!apiResponse.ok) {
        throw serverErrorByStatus(
          apiResponse.status,
          await extractResponseDetails(apiResponse),
          "getLocationsByCountries failed"
        )
      }

      const apiJson = await apiResponse.json()
      const verifiedLocations = locationsSchema.safeParse(apiJson)
      if (!verifiedLocations.success) {
        hotelUtilsLogger.error(
          `Locations Verification Failed`,
          verifiedLocations.error
        )
        throw new Error("Unable to parse api response for locations", {
          cause: verifiedLocations.error,
        })
      }

      const data = cleanData(verifiedLocations.data.data)
      const cities = data
        .filter((x) => x.type === "cities")
        .map((city) => addCountryDataToCity(city, citiesByCountry))

      const hotels = data
        .filter((x) => x.type === "hotels")
        .map((hotel) => addCityDataToHotel(hotel, cities))

      let locations: z.infer<typeof locationsSchema>["data"] = [
        ...cities,
        ...hotels,
      ]

      return locations
    },
    "1d"
  )
}

function addCityDataToHotel(hotel: Hotel, cities: City[]) {
  const city = cities.find((c) => c.id === hotel.relationships.city.id)
  if (!city) {
    hotelUtilsLogger.warn(
      `City with id ${hotel.relationships.city.id} not found for hotel ${hotel.id}`
    )
    return hotel
  }

  return {
    ...hotel,
    relationships: {
      city: {
        ...city,
        cityIdentifier: city.cityIdentifier,
        url: hotel.relationships.city.url,
        keywords: city.keyWords ?? [],
      },
    },
  } satisfies Hotel
}

function addCountryDataToCity(
  city: City,
  citiesByCountry: CitiesNamesByCountry | null
): City {
  if (!citiesByCountry) {
    return city
  }

  const country = Object.keys(citiesByCountry).find((country) =>
    citiesByCountry[country].find((loc) => loc.name === city.name)
  )
  if (!country) {
    hotelUtilsLogger.error(
      `Location cannot be found in any of the countries cities`,
      city
    )

    return city
  }

  return {
    ...city,
    country,
  }
}

function cleanData(data: z.infer<typeof locationsSchema>["data"]) {
  return data
    .filter((node) => {
      if (node?.isPublished !== true) {
        return false
      }
      if (node.type === "hotels" && !node.operaId) {
        return false
      }
      if (node.type === "cities" && !node.cityIdentifier) {
        return false
      }

      return true
    })
    .toSorted((a, b) => {
      if (a.type === b.type) {
        return a.name.localeCompare(b.name)
      } else {
        return a.type === "cities" ? -1 : 1
      }
    })
}

export const locationsSchema = z.object({
  data: z.array(
    z
      .discriminatedUnion("type", [locationCitySchema, locationHotelSchema])
      .transform((location) => {
        if (location.type === "cities") {
          return {
            ...location.attributes,
            country: location.attributes.countryName || "",
            id: location.id,
            type: location.type,
          }
        }
        return {
          ...location.attributes,
          id: location.id,
          relationships: {
            city: {
              cityIdentifier: undefined as string | undefined,
              id: extractCityId(
                location.relationships?.city?.links?.related ?? ""
              ),
              isPublished: false,
              keywords: [] as string[],
              name: undefined as string | undefined,
              type: "cities",
              url: location?.relationships?.city?.links?.related ?? "",
            },
          },
          type: location.type,
          operaId: location.attributes.operaId ?? "",
        }
      })
  ),
})

function extractCityId(cityUrl: string): string | null {
  try {
    const url = new URL(cityUrl)
    if (!url.pathname.toLowerCase().includes("/cities/")) {
      return null
    }

    const id = url.pathname.split("/").at(-1)

    return id ?? null
  } catch {
    return null
  }
}