import type * as types from './types.js'

export { default as delay } from 'delay'
export { default as assert } from 'tiny-invariant'

/**
 * From `inputObj`, create a new object that does not include `keys`.
 *
 * @example
 * ```js
 * omit({ a: 1, b: 2, c: 3 }, 'a', 'c') // { b: 2 }
 * ```
 */
export const omit = <
  T extends Record<any, unknown> | object,
  K extends keyof T = keyof T
>(
  inputObj: T,
  ...keys: K[]
): Omit<T, K> => {
  const keysSet = new Set(keys)
  return Object.fromEntries(
    Object.entries(inputObj).filter(([k]) => !keysSet.has(k as any))
  ) as any
}

/**
 * From `inputObj`, create a new object that only includes `keys`.
 *
 * @example
 * ```js
 * pick({ a: 1, b: 2, c: 3 }, 'a', 'c') // { a: 1, c: 3 }
 * ```
 */
export const pick = <
  T extends Record<any, unknown> | object,
  K extends keyof T = keyof T
>(
  inputObj: T,
  ...keys: K[]
): Pick<T, K> => {
  const keysSet = new Set(keys)
  return Object.fromEntries(
    Object.entries(inputObj).filter(([k]) => keysSet.has(k as any))
  ) as any
}

export function pruneUndefined<T extends Record<string, any>>(
  obj: T
): NonNullable<{ [K in keyof T]: Exclude<T[K], undefined> }> {
  return Object.fromEntries(
    Object.entries(obj).filter(([, value]) => value !== undefined)
  ) as NonNullable<T>
}

export function getEnv(name: string): string | undefined {
  try {
    return typeof process !== 'undefined'
      ? // eslint-disable-next-line no-process-env
        process.env?.[name]
      : undefined
  } catch {
    return undefined
  }
}

/**
 * Function that does nothing.
 */
export const noop = () => undefined

/**
 * Throttles HTTP requests made by a ky instance.
 *
 * Very useful for enforcing rate limits.
 */
export function throttleKy(
  ky: types.KyInstance,
  throttleFn: <Arguments extends readonly unknown[], ReturnValue>(
    function_: (...args_: Arguments) => ReturnValue
  ) => types.ThrottledFunction<(...args_: Arguments) => ReturnValue>
) {
  return ky.extend({
    hooks: {
      beforeRequest: [throttleFn(noop)]
    }
  })
}