import { HydrationState } from './hydration/hydrator.js'

export function createPipeline<Params, Skeleton, View, Context>(
  skeletonFn: SkeletonFn<Context, Params, Skeleton>,
  hydrationFn: HydrationFn<Context, Params, Skeleton>,
  rulesFn: RulesFn<Context, Params, Skeleton>,
  presentationFn: PresentationFn<Context, Params, Skeleton, View>,
) {
  return async (params: Params, ctx: Context) => {
    const skeleton = await skeletonFn({ ctx, params })
    const hydration = await hydrationFn({ ctx, params, skeleton })
    const appliedRules = rulesFn({ ctx, params, skeleton, hydration })
    return presentationFn({ ctx, params, skeleton: appliedRules, hydration })
  }
}

export type SkeletonFn<Context, Params, Skeleton> = (
  input: SkeletonFnInput<Context, Params>,
) => Promise<Skeleton>

export type SkeletonFnInput<Context, Params> = {
  ctx: Context
  params: Params
}

export type HydrationFn<Context, Params, Skeleton> = (
  input: HydrationFnInput<Context, Params, Skeleton>,
) => Promise<HydrationState>

export type HydrationFnInput<Context, Params, Skeleton> = {
  ctx: Context
  params: Params
  skeleton: Skeleton
}

export type RulesFn<Context, Params, Skeleton> = (
  input: RulesFnInput<Context, Params, Skeleton>,
) => Skeleton

export type RulesFnInput<Context, Params, Skeleton> = {
  ctx: Context
  params: Params
  skeleton: Skeleton
  hydration: HydrationState
}

export type PresentationFn<Context, Params, Skeleton, View> = (
  input: PresentationFnInput<Context, Params, Skeleton>,
) => View

export type PresentationFnInput<Context, Params, Skeleton> = {
  ctx: Context
  params: Params
  skeleton: Skeleton
  hydration: HydrationState
}

export function noRules<S>(input: { skeleton: S }) {
  return input.skeleton
}