export function isObject(item: unknown): item is Record<string, unknown> {
  return Boolean(item && typeof item === 'object' && !Array.isArray(item))
}

export function mergeDeep<T>(target: T, ...sources: T[]): T {
  if (!sources.length) return target
  const source = sources.shift()

  if (isObject(target) && isObject(source)) {
    for (const key in source) {
      if (isObject(source[key])) {
        if (!target[key]) Object.assign(target, { [key]: {} })
        mergeDeep(target[key] as T, source[key] as T)
      } else {
        Object.assign(target, { [key]: source[key] })
      }
    }
  }

  return mergeDeep(target, ...sources)
}

export function isPlainObject(obj: any): boolean {
  if (typeof obj !== 'object' || obj === null) return false

  let proto = obj
  while (Object.getPrototypeOf(proto) !== null) {
    proto = Object.getPrototypeOf(proto)
  }

  return Object.getPrototypeOf(obj) === proto
}