import { useStorage } from '@vueuse/core'
import { MemStorage, onScopeDispose, ref, syncRef, toRefs, watch } from '#imports'

interface UseSidebarProps {
  hasSidebar?: boolean
  isOpen?: boolean
  useStorage?: boolean
}

/**
 * States for sidebars
 *
 * Requires an id to work, id should correspond to the sidebar state you want to create or fetch
 * If `useSidebar` was not called before it will create a new state if no state can be found for the specified id
 */
const sidebarStorage = new MemStorage()

const createSidebar = (id: string, props: UseSidebarProps = {}) => {
  const isOpen = ref(props.isOpen ?? false)
  const hasSidebar = ref(props.hasSidebar ?? true)

  function toggle(state?: boolean) {
    isOpen.value = state ?? !isOpen.value
  }

  function toggleHasSidebar(state?: boolean) {
    hasSidebar.value = state ?? !hasSidebar.value
  }

  if (props.useStorage) {
    const storage = toRefs(useStorage(id, { isOpen, hasSidebar }, localStorage, { mergeDefaults: true }).value)
    syncRef(isOpen, storage.isOpen)
    syncRef(hasSidebar, storage.hasSidebar)
  }

  watch(
    hasSidebar,
    (nextHasSidebar) => {
      if (!nextHasSidebar) toggle(false)
    },
    { immediate: true },
  )

  watch(
    isOpen,
    (nextIsOpen) => {
      if (nextIsOpen && !hasSidebar.value) toggleHasSidebar(true)
    },
    { immediate: true },
  )

  return {
    isOpen,
    toggle,
    hasSidebar,
    toggleHasSidebar,
  }
}

export function useSidebar(id: string, props: UseSidebarProps = {}) {
  if (!id) throw new Error('useSidebar requires an id')

  if (!sidebarStorage.has(id)) {
    const sidebar = createSidebar(id, props)

    sidebarStorage.set(id, sidebar)

    onScopeDispose(() => {
      sidebarStorage.remove(id)
    })

    return sidebar
  } else {
    const sidebar = sidebarStorage.get(id)

    if (props.isOpen !== undefined) sidebar.isOpen.value = props.isOpen
    if (props.hasSidebar !== undefined) sidebar.hasSidebar.value = props.hasSidebar

    return sidebar
  }
}