import deepmerge from "deepmerge"
import { unstable_cache } from "next/cache"

import { Lang } from "@/constants/languages"
import { env } from "@/env/server"
import * as api from "@/lib/api"
import { toApiLang } from "@/server/utils"

import { getHotelPageUrls } from "../contentstack/hotelPage/utils"
import { metrics } from "./metrics"
import {
  citiesByCountrySchema,
  citiesSchema,
  countriesSchema,
  getHotelIdsSchema,
  locationsSchema,
} from "./output"
import { getHotel } from "./query"

import { PointOfInterestGroupEnum } from "@/types/enums/pointOfInterest"
import type { RequestOptionsWithOutBody } from "@/types/fetch"
import type { HotelDataWithUrl } from "@/types/hotel"
import type {
  CitiesGroupedByCountry,
  CityLocation,
  HotelLocation,
} from "@/types/trpc/routers/hotel/locations"
import type { Endpoint } from "@/lib/api/endpoints"

export function getPoiGroupByCategoryName(category: string | undefined) {
  if (!category) return PointOfInterestGroupEnum.LOCATION
  switch (category) {
    case "Airport":
    case "Bus terminal":
    case "Transportations":
      return PointOfInterestGroupEnum.PUBLIC_TRANSPORT
    case "Amusement park":
    case "Museum":
    case "Sports":
    case "Theatre":
    case "Tourist":
    case "Zoo":
      return PointOfInterestGroupEnum.ATTRACTIONS
    case "Nearby companies":
    case "Fair":
      return PointOfInterestGroupEnum.BUSINESS
    case "Parking / Garage":
      return PointOfInterestGroupEnum.PARKING
    case "Shopping":
    case "Restaurant":
      return PointOfInterestGroupEnum.SHOPPING_DINING
    case "Hospital":
    default:
      return PointOfInterestGroupEnum.LOCATION
  }
}

export const locationsAffix = "locations"

export const TWENTYFOUR_HOURS = 60 * 60 * 24
export async function getCity(
  cityUrl: string,
  options: RequestOptionsWithOutBody,
  lang: Lang,
  relationshipCity: HotelLocation["relationships"]["city"]
) {
  return unstable_cache(
    async function (locationCityUrl: string) {
      const url = new URL(locationCityUrl)
      const cityResponse = await api.get(
        url.pathname as Endpoint,
        options,
        url.searchParams
      )

      if (!cityResponse.ok) {
        return null
      }

      const cityJson = await cityResponse.json()
      const city = citiesSchema.safeParse(cityJson)
      if (!city.success) {
        console.info(`Validation of city failed`)
        console.info(`cityUrl: ${locationCityUrl}`)
        console.error(city.error)
        return null
      }

      return city.data
    },
    [cityUrl, `${lang}:${relationshipCity}`],
    { revalidate: TWENTYFOUR_HOURS }
  )(cityUrl)
}

export async function getCountries(
  options: RequestOptionsWithOutBody,
  params: URLSearchParams,
  lang: Lang
) {
  return unstable_cache(
    async function (searchParams) {
      const countryResponse = await api.get(
        api.endpoints.v1.Hotel.countries,
        options,
        searchParams
      )

      if (!countryResponse.ok) {
        return null
      }

      const countriesJson = await countryResponse.json()
      const countries = countriesSchema.safeParse(countriesJson)
      if (!countries.success) {
        console.info(`Validation for countries failed`)
        console.error(countries.error)
        return null
      }

      return countries.data
    },
    [`${lang}:${locationsAffix}:countries`, params.toString()],
    { revalidate: TWENTYFOUR_HOURS }
  )(params)
}

export async function getCitiesByCountry(
  countries: string[],
  options: RequestOptionsWithOutBody,
  params: URLSearchParams,
  lang: Lang,
  onlyPublished = false, // false by default as it might be used in other places
  affix: string = locationsAffix
) {
  return unstable_cache(
    async function (
      searchParams: URLSearchParams,
      searchedCountries: string[]
    ) {
      const citiesGroupedByCountry: CitiesGroupedByCountry = {}

      await Promise.all(
        searchedCountries.map(async (country) => {
          const countryResponse = await api.get(
            api.endpoints.v1.Hotel.Cities.country(country),
            options,
            searchParams
          )

          if (!countryResponse.ok) {
            return null
          }

          const countryJson = await countryResponse.json()
          const citiesByCountry = citiesByCountrySchema.safeParse(countryJson)
          if (!citiesByCountry.success) {
            console.info(`Failed to validate Cities by Country payload`)
            console.error(citiesByCountry.error)
            return null
          }

          const cities = onlyPublished
            ? citiesByCountry.data.data.filter((city) => city.isPublished)
            : citiesByCountry.data.data
          citiesGroupedByCountry[country] = cities
          return true
        })
      )

      return citiesGroupedByCountry
    },
    [
      `${lang}:${affix}:cities-by-country`,
      params.toString(),
      JSON.stringify(countries),
    ],
    { revalidate: TWENTYFOUR_HOURS }
  )(params, countries)
}

export async function getLocations(
  lang: Lang,
  options: RequestOptionsWithOutBody,
  params: URLSearchParams,
  citiesByCountry: CitiesGroupedByCountry | null
) {
  return unstable_cache(
    async function (
      searchParams: URLSearchParams,
      groupedCitiesByCountry: CitiesGroupedByCountry | null
    ) {
      const apiResponse = await api.get(
        api.endpoints.v1.Hotel.locations,
        options,
        searchParams
      )

      if (!apiResponse.ok) {
        if (apiResponse.status === 401) {
          return { error: true, cause: "unauthorized" } as const
        } else if (apiResponse.status === 403) {
          return { error: true, cause: "forbidden" } as const
        }
        return null
      }

      const apiJson = await apiResponse.json()
      const verifiedLocations = locationsSchema.safeParse(apiJson)
      if (!verifiedLocations.success) {
        console.info(`Locations Verification Failed`)
        console.error(verifiedLocations.error)
        return null
      }

      return await Promise.all(
        verifiedLocations.data.data.map(async (location) => {
          if (location.type === "cities") {
            if (groupedCitiesByCountry) {
              const country = Object.keys(groupedCitiesByCountry).find(
                (country) => {
                  if (
                    groupedCitiesByCountry[country].find(
                      (loc) => loc.name === location.name
                    )
                  ) {
                    return true
                  }
                  return false
                }
              )
              if (country) {
                return {
                  ...location,
                  country,
                }
              } else {
                console.info(
                  `Location cannot be found in any of the countries cities`
                )
                console.info(location)
              }
            }
          } else if (location.type === "hotels") {
            if (location.relationships.city?.url) {
              const city = await getCity(
                location.relationships.city.url,
                options,
                lang,
                location.relationships.city
              )
              if (city) {
                return deepmerge(location, {
                  relationships: {
                    city,
                  },
                })
              }
            }
          }

          return location
        })
      )
    },
    [
      `${lang}:${locationsAffix}`,
      params.toString(),
      JSON.stringify(citiesByCountry),
    ],
    { revalidate: TWENTYFOUR_HOURS }
  )(params, citiesByCountry)
}

export async function getHotelIdsByCityId(
  cityId: string,
  options: RequestOptionsWithOutBody,
  params: URLSearchParams
) {
  return unstable_cache(
    async function (params: URLSearchParams) {
      metrics.hotelIds.counter.add(1, { params: params.toString() })
      console.info(
        "api.hotel.hotel-ids start",
        JSON.stringify({ params: params.toString() })
      )
      const apiResponse = await api.get(
        api.endpoints.v1.Hotel.hotels,
        options,
        params
      )

      if (!apiResponse.ok) {
        const responseMessage = await apiResponse.text()
        metrics.hotelIds.fail.add(1, {
          params: params.toString(),
          error_type: "http_error",
          error: responseMessage,
        })
        console.error(
          "api.hotel.hotel-ids fetch error",
          JSON.stringify({
            params: params.toString(),
            error: {
              status: apiResponse.status,
              statusText: apiResponse.statusText,
              text: responseMessage,
            },
          })
        )

        return []
      }

      const apiJson = await apiResponse.json()
      const validatedHotelIds = getHotelIdsSchema.safeParse(apiJson)
      if (!validatedHotelIds.success) {
        metrics.hotelIds.fail.add(1, {
          params: params.toString(),
          error_type: "validation_error",
          error: JSON.stringify(validatedHotelIds.error),
        })
        console.error(
          "api.hotel.hotel-ids validation error",
          JSON.stringify({
            params: params.toString(),
            error: validatedHotelIds.error,
          })
        )
        return []
      }

      metrics.hotelIds.success.add(1, { cityId })
      console.info(
        "api.hotel.hotel-ids success",
        JSON.stringify({
          params: params.toString(),
          response: validatedHotelIds.data,
        })
      )

      return validatedHotelIds.data
    },
    [`hotelsByCityId`, params.toString()],
    { revalidate: env.CACHE_TIME_HOTELS }
  )(params)
}

export async function getHotelIdsByCountry(
  country: string,
  options: RequestOptionsWithOutBody,
  params: URLSearchParams
) {
  return unstable_cache(
    async function (params: URLSearchParams) {
      metrics.hotelIds.counter.add(1, { country })
      console.info(
        "api.hotel.hotel-ids start",
        JSON.stringify({ query: { country } })
      )
      const apiResponse = await api.get(
        api.endpoints.v1.Hotel.hotels,
        options,
        params
      )

      if (!apiResponse.ok) {
        const responseMessage = await apiResponse.text()
        metrics.hotelIds.fail.add(1, {
          country,
          error_type: "http_error",
          error: responseMessage,
        })
        console.error(
          "api.hotel.hotel-ids fetch error",
          JSON.stringify({
            query: { country },
            error: {
              status: apiResponse.status,
              statusText: apiResponse.statusText,
              text: responseMessage,
            },
          })
        )

        return []
      }

      const apiJson = await apiResponse.json()
      const validatedHotelIds = getHotelIdsSchema.safeParse(apiJson)
      if (!validatedHotelIds.success) {
        metrics.hotelIds.fail.add(1, {
          country,
          error_type: "validation_error",
          error: JSON.stringify(validatedHotelIds.error),
        })
        console.error(
          "api.hotel.hotel-ids validation error",
          JSON.stringify({
            query: { country },
            error: validatedHotelIds.error,
          })
        )
        return []
      }

      metrics.hotelIds.success.add(1, { country })
      console.info(
        "api.hotel.hotel-ids success",
        JSON.stringify({ query: { country } })
      )

      return validatedHotelIds.data
    },
    [`hotelsByCountry`, params.toString()],
    { revalidate: env.CACHE_TIME_HOTELS }
  )(params)
}

export async function getHotelIdsByCityIdentifier(
  cityIdentifier: string,
  serviceToken: string
) {
  const apiLang = toApiLang(Lang.en)
  const city = await getCityByCityIdentifier(cityIdentifier, serviceToken)

  if (!city) {
    return []
  }

  const hotelIdsParams = new URLSearchParams({
    language: apiLang,
    city: city.id,
  })
  const options: RequestOptionsWithOutBody = {
    // needs to clear default option as only
    // cache or next.revalidate is permitted
    cache: undefined,
    headers: {
      Authorization: `Bearer ${serviceToken}`,
    },
    next: {
      revalidate: env.CACHE_TIME_HOTELS,
    },
  }
  const hotelIds = await getHotelIdsByCityId(city.id, options, hotelIdsParams)
  return hotelIds
}

export async function getCityByCityIdentifier(
  cityIdentifier: string,
  serviceToken: string
) {
  const lang = Lang.en
  const apiLang = toApiLang(lang)
  const options: RequestOptionsWithOutBody = {
    // needs to clear default option as only
    // cache or next.revalidate is permitted
    cache: undefined,
    headers: {
      Authorization: `Bearer ${serviceToken}`,
    },
    next: {
      revalidate: env.CACHE_TIME_HOTELS,
    },
  }
  const params = new URLSearchParams({
    language: apiLang,
  })
  const locations = await getLocations(lang, options, params, null)
  if (!locations || "error" in locations) {
    return null
  }

  const city = locations
    .filter((loc): loc is CityLocation => loc.type === "cities")
    .find((loc) => loc.cityIdentifier === cityIdentifier)

  return city ?? null
}

export async function getHotelsByHotelIds(
  hotelIds: string[],
  lang: Lang,
  serviceToken: string
) {
  const hotelPages = await getHotelPageUrls(lang)
  const hotels = await Promise.all(
    hotelIds.map(async (hotelId) => {
      const hotelData = await getHotel(
        { hotelId, language: lang, isCardOnlyPayment: false },
        serviceToken
      )
      const hotelPage = hotelPages.find((page) => page.hotelId === hotelId)
      return hotelData ? { ...hotelData, url: hotelPage?.url ?? null } : null
    })
  )

  return hotels.filter((hotel): hotel is HotelDataWithUrl => !!hotel)
}