import {
  APP_PREFERENCES_STORAGE_KEY,
  AUDIO_PREFERENCES_STORAGE_KEY,
  LOGIN_PROMPT_DEDUP_MS,
} from '@/constants'
import i18n from '@/i18n'
import { notify } from '@/lib/notify'
import { queryClient } from '@/lib/query/query-client'
import { useAuthStore } from '@/store/auth'
import { useModalStore } from '@/store/modal'
import type {
  AuthSessionInput,
  AuthUser,
  ClearAuthenticatedSessionOptions,
  CurrentUserInitializer,
  RefreshSessionHandler,
  UnauthorizedSessionOptions,
} from '@/type'

let currentUserInitializer: CurrentUserInitializer | null = null
let refreshSessionHandler: RefreshSessionHandler | null = null
let authInitializationPromise: Promise<void> | null = null
let refreshSessionPromise: Promise<boolean> | null = null
let lastLoginPromptAt = 0

const PRESERVED_LOCAL_STORAGE_KEYS = [
  APP_PREFERENCES_STORAGE_KEY,
  AUDIO_PREFERENCES_STORAGE_KEY,
]

function clearBrowserStorageData() {
  if (typeof localStorage !== 'undefined') {
    const preserved = PRESERVED_LOCAL_STORAGE_KEYS.map(
      (key) => [key, localStorage.getItem(key)] as const,
    )

    localStorage.clear()

    for (const [key, value] of preserved) {
      if (value !== null) {
        localStorage.setItem(key, value)
      }
    }
  }

  if (typeof sessionStorage !== 'undefined') {
    sessionStorage.clear()
  }
}

function hasClearableSessionState() {
  const snapshot = useAuthStore.getState()

  return Boolean(
    snapshot.status !== 'anonymous' ||
      snapshot.accessToken ||
      snapshot.refreshToken ||
      snapshot.currentUser ||
      snapshot.apiAuthToken ||
      snapshot.apiAuthTokenExpiresAt ||
      snapshot.apiAuthServerTime,
  )
}

function hasRecordedUnauthorizedSession() {
  const snapshot = useAuthStore.getState()

  return snapshot.status === 'anonymous' && Boolean(snapshot.lastUnauthorizedAt)
}

export function registerCurrentUserInitializer(
  initializer: CurrentUserInitializer | null,
) {
  currentUserInitializer = initializer
}

export function registerRefreshSessionHandler(
  handler: RefreshSessionHandler | null,
) {
  refreshSessionHandler = handler
}

export function isAuthenticated() {
  const snapshot = useAuthStore.getState()

  return snapshot.status === 'authenticated' && Boolean(snapshot.accessToken)
}

export function clearAuthenticatedSession({
  clearBrowserStorage = true,
  clearQueryCache = true,
}: ClearAuthenticatedSessionOptions = {}) {
  const alreadyUnauthorized = hasRecordedUnauthorizedSession()

  if (!alreadyUnauthorized) {
    useAuthStore.getState().markUnauthorized()
  }

  if (clearQueryCache && !alreadyUnauthorized) {
    queryClient.clear()
  }

  if (clearBrowserStorage && !alreadyUnauthorized) {
    clearBrowserStorageData()
  }
}

export function handleUnauthorizedSession({
  clearBrowserStorage = false,
  openLoginModal = false,
  showLoginRequiredToast = false,
}: UnauthorizedSessionOptions = {}) {
  clearAuthenticatedSession({
    clearBrowserStorage,
    clearQueryCache: hasClearableSessionState(),
  })

  if (!openLoginModal && !showLoginRequiredToast) {
    return
  }

  const modalStore = openLoginModal ? useModalStore.getState() : null

  if (modalStore?.modals.desktopLogin) {
    return
  }

  const now = Date.now()
  const shouldPrompt = now - lastLoginPromptAt > LOGIN_PROMPT_DEDUP_MS

  if (!shouldPrompt) {
    return
  }

  lastLoginPromptAt = now

  if (showLoginRequiredToast) {
    notify.warning(i18n.t('commonUi.toast.loginRequired'))
  }

  if (openLoginModal) {
    modalStore?.openExclusiveModal('desktopLogin')
  }
}

export function handleInvalidTokenSession() {
  handleUnauthorizedSession({
    clearBrowserStorage: true,
    openLoginModal: true,
    showLoginRequiredToast: true,
  })
}

export async function initializeAuthSession() {
  if (authInitializationPromise) {
    return authInitializationPromise
  }

  authInitializationPromise = (async () => {
    await useAuthStore.persist.rehydrate()

    const snapshot = useAuthStore.getState()

    if (
      !snapshot.accessToken ||
      snapshot.currentUser ||
      !currentUserInitializer
    ) {
      return
    }

    const currentUser = await currentUserInitializer()

    useAuthStore.getState().setCurrentUser(currentUser)
  })().finally(() => {
    authInitializationPromise = null
  })

  return authInitializationPromise
}

export async function hydrateCurrentUser(initializer: CurrentUserInitializer) {
  const currentUser = await initializer()

  useAuthStore.getState().setCurrentUser(currentUser)

  return currentUser
}

export async function tryRefreshAuthSession() {
  if (refreshSessionPromise) {
    return refreshSessionPromise
  }

  const snapshot = useAuthStore.getState()

  if (!snapshot.refreshToken || !refreshSessionHandler) {
    return false
  }

  const refreshToken = snapshot.refreshToken

  refreshSessionPromise = (async () => {
    try {
      const nextSession = await refreshSessionHandler(refreshToken)

      if (!nextSession?.accessToken) {
        handleUnauthorizedSession()

        return false
      }

      useAuthStore.getState().startSession({
        accessToken: nextSession.accessToken,
        accessTokenExpiresAt:
          nextSession.accessTokenExpiresAt ?? snapshot.accessTokenExpiresAt,
        currentUser: nextSession.currentUser ?? snapshot.currentUser,
        refreshToken: nextSession.refreshToken ?? snapshot.refreshToken,
      })

      return true
    } catch {
      handleUnauthorizedSession()

      return false
    } finally {
      refreshSessionPromise = null
    }
  })()

  return refreshSessionPromise
}