import React, { forwardRef, useImperativeHandle } from 'react'
import {
  createSearchState,
  useSearchkit,
  useSearchkitRoutingOptions,
  useSearchkitVariables
} from './searchkit'

interface FilterLinkProps {
  filter: any
  resetPagination?: boolean
  children: React.ReactChildren | React.ReactChild
}

interface PaginationLinkProps {
  page: number
  children: React.ReactChildren | React.ReactChild
}

export type FilterLinkClickRef = { onClick: (e: React.MouseEvent) => void }

function isModifiedEvent(event: React.MouseEvent): boolean {
  const { target } = event.currentTarget as HTMLAnchorElement
  return (
    (target && target !== '_self') ||
    event.metaKey ||
    event.ctrlKey ||
    event.shiftKey ||
    event.altKey || // triggers resource download
    (event.nativeEvent && event.nativeEvent.which === 2)
  )
}

export const FilterLink = forwardRef<FilterLinkClickRef, FilterLinkProps>((props, ref) => {
  const { filter, resetPagination = true, children } = props
  const api = useSearchkit()
  const variables = useSearchkitVariables()
  const routingOptions = useSearchkitRoutingOptions()
  let href
  const filterAdded = api.isFilterSelected(filter)

  if (routingOptions) {
    const scs = createSearchState(variables)
    scs.toggleFilter(filter)
    if (resetPagination) scs.resetPage()
    if (filter.level) {
      const appliedFilters = scs.getFiltersByIdentifier(filter.identifier)
      const levelFilters = appliedFilters.filter(
        (f) => f.level === filter.level || (!filterAdded && f.level > filter.level)
      )
      if (levelFilters?.length > 0) {
        levelFilters.forEach((f) => scs.removeFilter(f))
      }
    }
    const nextRouteState = routingOptions.stateToRoute(scs.searchState)
    href = routingOptions.createURL({ routeState: nextRouteState })
  }

  const clickHandler = (e: React.MouseEvent) => {
    const { nodeName } = e.currentTarget

    if (nodeName === 'A' && isModifiedEvent(e)) {
      return
    }

    e.preventDefault()

    api.toggleFilter(filter)
    if (resetPagination) api.resetPage()
    if (filter.level) {
      const appliedFilters = api.getFiltersByIdentifier(filter.identifier)
      const levelFilters = appliedFilters.filter(
        (f) => f.level === filter.level || f.level > filter.level
      )
      if (levelFilters?.length > 0) {
        levelFilters.forEach((f) => api.removeFilter(f))
      }
    }
    api.search()
  }

  useImperativeHandle(ref, () => ({
    onClick: (e) => {
      clickHandler(e)
    }
  }))

  return (
    <a href={href} onClick={!ref ? clickHandler : undefined}>
      {children}
    </a>
  )
})

export function PaginationLink({ page, children }: PaginationLinkProps) {
  const api = useSearchkit()
  const variables = useSearchkitVariables()
  const routingOptions = useSearchkitRoutingOptions()
  const from = variables.page.size * (page - 1)
  let href

  if (routingOptions) {
    const scs = createSearchState(variables)
    scs.setPage({
      from,
      size: variables.page.size
    })
    const nextRouteState = routingOptions.stateToRoute(scs.searchState)
    href = routingOptions.createURL({ routeState: nextRouteState })
  }

  const clickHandler = (e) => {
    const { nodeName } = e.currentTarget

    if (nodeName === 'A' && isModifiedEvent(e)) {
      return
    }

    e.preventDefault()

    api.setPage({
      from,
      size: variables.page.size
    })
    api.search()
  }

  return (
    <a href={href} onClick={clickHandler}>
      {children}
    </a>
  )
}