import * as React from "react"
import type { ToastActionElement, ToastProps } from "@/components/ui/toast"

// Based on shadcn/ui toast hook implementation
export type Toast = Omit<ToastProps, "id"> & {
  id: string
  title?: React.ReactNode
  description?: React.ReactNode
  action?: ToastActionElement
}

const TOAST_LIMIT = 5
const TOAST_REMOVE_DELAY = 1000

type State = {
  toasts: Toast[]
}

type ToastInput = Omit<Toast, "id">

type Listener = (state: State) => void

let count = 0
function genId() {
  count = (count + 1) % Number.MAX_SAFE_INTEGER
  return count.toString()
}

const toastTimeouts = new Map<string, ReturnType<typeof setTimeout>>()

const state: State = { toasts: [] }
const listeners: Listener[] = []

function setState(newState: Partial<State>) {
  Object.assign(state, newState)
  listeners.forEach((l) => l(state))
}

function addToast(toast: ToastInput) {
  const id = genId()

  const newToast: Toast = {
    ...toast,
    id,
    open: true as any,
  }

  // Ensure limit
  const nextToasts = [newToast, ...state.toasts].slice(0, TOAST_LIMIT)

  setState({ toasts: nextToasts })

  return id
}

function updateToast(id: string, update: Partial<Toast>) {
  setState({
    toasts: state.toasts.map((t) => (t.id === id ? { ...t, ...update } : t)),
  })
}

function dismissToast(id?: string) {
  if (id) {
    queueRemoval(id)
    updateToast(id, { open: false } as any)
  } else {
    state.toasts.forEach((t) => {
      queueRemoval(t.id)
      updateToast(t.id, { open: false } as any)
    })
  }
}

function removeToast(id?: string) {
  if (id) {
    setState({ toasts: state.toasts.filter((t) => t.id !== id) })
  } else {
    setState({ toasts: [] })
  }
}

function queueRemoval(id: string) {
  if (toastTimeouts.has(id)) return
  const timeout = setTimeout(() => {
    toastTimeouts.delete(id)
    removeToast(id)
  }, TOAST_REMOVE_DELAY)
  toastTimeouts.set(id, timeout)
}

export function useToast() {
  const [localState, setLocalState] = React.useState<State>(state)

  React.useEffect(() => {
    listeners.push(setLocalState)
    return () => {
      const index = listeners.indexOf(setLocalState)
      if (index > -1) listeners.splice(index, 1)
    }
  }, [])

  return {
    ...localState,
    toast: ({ ...props }: ToastInput) => addToast(props),
    dismiss: (id?: string) => dismissToast(id),
    remove: (id?: string) => removeToast(id),
  }
}

export type { ToastActionElement, ToastProps }