import { Context, Effect, Option } from "effect-app"
import { accessEffectFn } from "effect-app/Context"

export type ToastId = string | number
export type ToastOpts = { id?: ToastId; timeout?: number }
export type ToastOptsInternal = { id?: ToastId | null; timeout?: number }

export type UseToast = () => {
  error: (this: void, message: string, options?: ToastOpts) => ToastId
  warning: (this: void, message: string, options?: ToastOpts) => ToastId
  success: (this: void, message: string, options?: ToastOpts) => ToastId
  info: (this: void, message: string, options?: ToastOpts) => ToastId
  dismiss: (this: void, id: ToastId) => void
}

export class CurrentToastId extends Context.Opaque<CurrentToastId, { toastId: ToastId }>()("CurrentToastId") {}

/** fallback to CurrentToastId when available unless id is explicitly set to a value or null */
export const wrap = (toast: ReturnType<UseToast>) => {
  const wrap = (toastHandler: (message: string, options?: ToastOpts) => ToastId) => {
    return (message: string, options?: ToastOptsInternal) =>
      Effect.serviceOption(CurrentToastId).pipe(
        Effect.flatMap((currentToast) =>
          Effect.sync(() => {
            const { id: _id, ...rest } = options ?? {}
            const id = _id !== undefined
              ? _id ?? undefined
              : Option.getOrUndefined(Option.map(currentToast, (_) => _.toastId))
            // when id is undefined, we may end up with no toast at all..
            return toastHandler(message, id !== undefined ? { ...rest, id } : rest)
          })
        )
      )
  }
  return {
    error: wrap(toast.error),
    info: wrap(toast.info),
    success: wrap(toast.success),
    warning: wrap(toast.warning),
    dismiss: (toastId: ToastId) => Effect.sync(() => toast.dismiss(toastId))
  }
}

type ToastShape = ReturnType<typeof wrap>

export class Toast extends Context.Opaque<Toast, ToastShape>()("Toast") {
  static readonly error = accessEffectFn(this, "error")
  static readonly info = accessEffectFn(this, "info")
  static readonly success = accessEffectFn(this, "success")
  static readonly warning = accessEffectFn(this, "warning")
  static readonly dismiss = accessEffectFn(this, "dismiss")
}