"use client"

import { zodResolver } from "@hookform/resolvers/zod"
import { cx } from "class-variance-authority"
import { useSearchParams } from "next/navigation"
import { use, useEffect, useRef, useState } from "react"
import { FormProvider, useForm } from "react-hook-form"
import { useIntl } from "react-intl"

import { dt } from "@scandic-hotels/common/dt"
import { useScrollLock } from "@scandic-hotels/common/hooks/useScrollLock"
import useStickyPosition from "@scandic-hotels/common/hooks/useStickyPosition"
import { StickyElementNameEnum } from "@scandic-hotels/common/stores/sticky-position"
import { debounce } from "@scandic-hotels/common/utils/debounce"
import isValidJson from "@scandic-hotels/common/utils/isValidJson"
import { IconButton } from "@scandic-hotels/design-system/IconButton"
import { trpc } from "@scandic-hotels/trpc/client"
import { SEARCH_TYPE_REDEMPTION } from "@scandic-hotels/trpc/constants/booking"

import { useBookingFlowConfig } from "../../bookingFlowConfig/bookingFlowConfigContext"
import { useBookingWidgetState } from "../../hooks/useBookingWidgetState"
import useLang from "../../hooks/useLang"
import {
  type bookingCodeSchema,
  bookingWidgetSchema,
} from "./BookingWidgetForm/schema"
import Form from "./BookingWidgetForm"
import MobileToggleButton from "./MobileToggleButton"
import { BookingWidgetSkeleton } from "./Skeleton"
import {
  bookingWidgetContainerVariants,
  formContainerVariants,
} from "./variant"

import styles from "./bookingWidget.module.css"

import type { z } from "zod"

import type { BookingWidgetSearchData, BookingWidgetType } from "."

export type BookingWidgetSchema = z.output<typeof bookingWidgetSchema>
export type BookingCodeSchema = z.output<typeof bookingCodeSchema>

export type BookingWidgetClientProps = {
  type?: BookingWidgetType
  data: BookingWidgetSearchData
  pageSettingsBookingCodePromise: Promise<string> | null
  isFloating?: boolean
}
export const FOCUS_WIDGET = "focusWidget"

export default function BookingWidgetClient({
  type,
  data,
  pageSettingsBookingCodePromise,
  isFloating = false,
}: BookingWidgetClientProps) {
  const searchParams = useSearchParams()
  const focusWidget = searchParams.get(FOCUS_WIDGET) === "true"

  const [isOpen, setIsOpen] = useState(focusWidget)
  const bookingWidgetRef = useRef(null)
  const lang = useLang()
  const bookingFlowConfig = useBookingFlowConfig()
  const storedBookingWidgetState = useBookingWidgetState()
  const { lockScroll, unlockScroll } = useScrollLock({
    autoLock: false,
  })
  const shouldFetchAutoComplete = !!data.hotelId || !!data.city
  const intl = useIntl()

  const { data: destinationsData, isPending } =
    trpc.autocomplete.destinations.useQuery(
      {
        lang,
        query: "",
        includeTypes: ["hotels", "cities"],
        selectedHotelId: data.hotelId ? data.hotelId.toString() : undefined,
        selectedCity: data.city,
      },
      { enabled: shouldFetchAutoComplete }
    )
  const shouldShowSkeleton = shouldFetchAutoComplete && isPending

  useStickyPosition({
    ref: bookingWidgetRef,
    name: StickyElementNameEnum.BOOKING_WIDGET,
  })

  const now = dt()
  // if fromDate or toDate is undefined, dt will return value that represents the same as 'now' above.
  // this is fine as isDateParamValid will catch this and default the values accordingly.
  let fromDate = dt(data.fromDate)
  let toDate = dt(data.toDate)

  const isDateParamValid =
    fromDate.isValid() &&
    toDate.isValid() &&
    fromDate.isSameOrAfter(now, "day") &&
    toDate.isAfter(fromDate)

  if (!isDateParamValid) {
    fromDate = now
    toDate = now.add(1, "day")
  }

  const selectedLocation =
    destinationsData?.currentSelection.hotel ??
    destinationsData?.currentSelection.city

  // if bookingCode is not provided in the search params,
  // we will fetch it from the page settings stored in Contentstack.
  const selectedBookingCode =
    data.bookingCode ||
    (pageSettingsBookingCodePromise !== null
      ? use(pageSettingsBookingCodePromise)
      : "")

  const defaultRoomsData: BookingWidgetSchema["rooms"] = data.rooms?.map(
    (room) => ({
      adults: room.adults,
      childrenInRoom: room.childrenInRoom || [],
    })
  ) ?? [
    {
      adults: 1,
      childrenInRoom: [],
    },
  ]
  const hotelId = data.hotelId ? parseInt(data.hotelId) : undefined
  const methods = useForm({
    defaultValues: {
      search: selectedLocation?.name ?? "",
      // Only used for displaying the selected location for mobile, not for actual form input
      selectedSearch: selectedLocation?.name ?? "",
      date: {
        fromDate: fromDate.format("YYYY-MM-DD"),
        toDate: toDate.format("YYYY-MM-DD"),
      },
      bookingCode: {
        value: bookingFlowConfig.bookingCodeEnabled ? selectedBookingCode : "",
        remember: false,
      },
      redemption: data.searchType === SEARCH_TYPE_REDEMPTION,
      rooms: defaultRoomsData,
      city: data.city || undefined,
      hotel: hotelId,
    },
    shouldFocusError: false,
    mode: "onSubmit",
    resolver: zodResolver(bookingWidgetSchema),
    reValidateMode: "onSubmit",
  })

  const bookingCodeFromSearchParams = searchParams.get("bookingCode") || ""
  const [bookingCode, setBookingCode] = useState(bookingCodeFromSearchParams)

  if (bookingCode !== bookingCodeFromSearchParams) {
    methods.setValue("bookingCode", {
      value: bookingCodeFromSearchParams,
    })
    setBookingCode(bookingCodeFromSearchParams)
  }

  useEffect(() => {
    if (!selectedLocation) return

    /*
      If `trpc.hotel.locations.get.useQuery` hasn't been fetched previously and is hence async
      we need to update the default values when data is available
    */
    methods.setValue("search", selectedLocation.name)
    methods.setValue("selectedSearch", selectedLocation.name)
  }, [selectedLocation, methods])

  function closeMobileSearch() {
    unlockScroll()
    setIsOpen(false)
  }

  function openMobileSearch() {
    lockScroll()
    setIsOpen(true)
  }

  useEffect(() => {
    const observer = new ResizeObserver(
      debounce(([entry]) => {
        if (entry.contentRect.width > 768) {
          setIsOpen(false)
          unlockScroll()
        }
      })
    )

    observer.observe(document.body)

    return () => {
      observer.unobserve(document.body)
    }
  }, [unlockScroll])

  useEffect(() => {
    if (!window?.sessionStorage || !window?.localStorage) return

    if (!selectedBookingCode) {
      const storedBookingCode = localStorage.getItem("bookingCode")
      const initialBookingCode: BookingCodeSchema | undefined =
        storedBookingCode && isValidJson(storedBookingCode)
          ? JSON.parse(storedBookingCode)
          : undefined

      if (initialBookingCode?.remember) {
        methods.setValue("bookingCode", initialBookingCode)
      }
    }
  }, [methods, selectedBookingCode])

  useEffect(() => {
    if (
      !data.fromDate &&
      !data.toDate &&
      !data.rooms &&
      storedBookingWidgetState
    ) {
      methods.reset({
        ...methods.getValues(),
        date: {
          fromDate: storedBookingWidgetState.fromDate,
          toDate: storedBookingWidgetState.toDate,
        },
        rooms: storedBookingWidgetState.rooms,
      })
    }
  }, [data, methods, storedBookingWidgetState])

  if (shouldShowSkeleton) {
    return <BookingWidgetSkeleton type={type} config={bookingFlowConfig} />
  }

  const classNames = bookingWidgetContainerVariants({
    type,
  })

  const formContainerClassNames = formContainerVariants({
    type,
  })

  return (
    <FormProvider {...methods}>
      <section
        ref={bookingWidgetRef}
        className={cx(classNames, { [styles.floating]: isFloating })}
        data-booking-widget-open={isOpen}
      >
        <MobileToggleButton
          openMobileSearch={openMobileSearch}
          isFloating={isFloating}
        />
        <div className={styles.backdrop} onClick={closeMobileSearch} />
        <div className={formContainerClassNames}>
          <IconButton
            className={styles.close}
            variant="Muted"
            emphasis
            aria-label={intl.formatMessage({
              id: "common.close",
              defaultMessage: "Close",
            })}
            onPress={closeMobileSearch}
            iconName="close"
          />
          <Form
            type={type}
            onClose={closeMobileSearch}
            isFloating={isFloating}
          />
        </div>
      </section>
    </FormProvider>
  )
}
