// Copyright © 2024 650 Industries.
'use client'

import { type RouterFactory, StackRouter, useNavigationBuilder } from '@react-navigation/native'
import * as React from 'react'
import { SafeAreaView } from 'react-native-safe-area-context'

import { Screen } from './Screen'
import { useContextKey } from '../Route'
import { useFilterScreenChildren } from '../layouts/withLayoutContext'
import { useSortedScreens } from '../useScreens'

type NavigatorTypes = ReturnType<typeof useNavigationBuilder>

// TODO: This might already exist upstream, maybe something like `useCurrentRender` ?
export const NavigatorContext = React.createContext<{
  contextKey: string
  state: NavigatorTypes['state']
  navigation: NavigatorTypes['navigation']
  descriptors: NavigatorTypes['descriptors']
  router: RouterFactory<any, any, any>
} | null>(null)

if (process.env.NODE_ENV !== 'production') {
  NavigatorContext.displayName = 'NavigatorContext'
}

export type NavigatorProps = {
  initialRouteName?: Parameters<typeof useNavigationBuilder>[1]['initialRouteName']
  screenOptions?: Parameters<typeof useNavigationBuilder>[1]['screenOptions']
  children?: Parameters<typeof useNavigationBuilder>[1]['children']
  router?: Parameters<typeof useNavigationBuilder>[0]
}

/** An unstyled custom navigator. Good for basic web layouts */
export function Navigator({ initialRouteName, screenOptions, children, router }: NavigatorProps) {
  const contextKey = useContextKey()

  // Allows adding Screen components as children to configure routes.
  const { screens, children: otherSlot } = useFilterScreenChildren(children, {
    isCustomNavigator: true,
    contextKey,
  })

  const sorted = useSortedScreens(screens ?? [])

  if (!sorted.length) {
    console.warn(`Navigator at "${contextKey}" has no children.`)
    return null
  }

  return (
    <QualifiedNavigator
      initialRouteName={initialRouteName}
      screenOptions={screenOptions}
      screens={sorted}
      contextKey={contextKey}
      router={router}
    >
      {otherSlot}
    </QualifiedNavigator>
  )
}

function QualifiedNavigator({
  initialRouteName,
  screenOptions,
  children,
  screens,
  contextKey,
  router = StackRouter,
}: NavigatorProps & { contextKey: string; screens: React.ReactNode[] }) {
  const { state, navigation, descriptors, NavigationContent } = useNavigationBuilder(router, {
    // Used for getting the parent with navigation.getParent('/normalized/path')
    id: contextKey,
    children: screens,
    screenOptions,
    initialRouteName,
  })

  return (
    <NavigatorContext.Provider
      value={{
        contextKey,
        state,
        navigation,
        descriptors,
        router,
      }}
    >
      <NavigationContent>{children}</NavigationContent>
    </NavigatorContext.Provider>
  )
}

export function useNavigatorContext() {
  const context = React.useContext(NavigatorContext)
  if (!context) {
    throw new Error('useNavigatorContext must be used within a <Navigator />')
  }
  return context
}

export function useSlot() {
  const context = useNavigatorContext()

  const { state, descriptors } = context

  const current = state.routes.find((route, i) => {
    return state.index === i
  })

  if (!current) {
    return null
  }

  return descriptors[current.key]?.render() ?? null
}

/** Renders the currently selected content. */
export function Slot(props: Omit<NavigatorProps, 'children'>) {
  const contextKey = useContextKey()
  const context = React.useContext(NavigatorContext)

  // Ensure the context is for the current contextKey
  if (context?.contextKey !== contextKey) {
    // Qualify the content and re-export.
    return (
      <Navigator {...props}>
        <QualifiedSlot />
      </Navigator>
    )
  }

  return <QualifiedSlot />
}

export function QualifiedSlot() {
  return useSlot()
}

export function DefaultNavigator() {
  return (
    <SafeAreaView style={{ flex: 1 }}>
      <Navigator>
        <QualifiedSlot />
      </Navigator>
    </SafeAreaView>
  )
}

Navigator.Slot = Slot
Navigator.useContext = useNavigatorContext

/** Used to configure route settings. */
Navigator.Screen = Screen