type InspectableObject = Record<string | number | symbol, unknown>;

function isObject(o: unknown): o is InspectableObject {
  return Object.prototype.toString.call(o) === '[object Object]';
}

export function isPlainObject(o: unknown): o is InspectableObject {
  if (!isObject(o)) {
    return false;
  }

  // If has modified constructor
  const ctor = o.constructor;
  if (ctor === undefined) {
    return true;
  }

  // If has modified prototype
  const prot = ctor.prototype;
  if (isObject(prot) === false) {
    return false;
  }

  // If constructor does not have an Object-specific method
  if (prot.hasOwnProperty('isPrototypeOf') === false) {
    return false;
  }

  // Most likely a plain Object
  return true;
}

// Slates deep equality function: https://github.com/ianstormtaylor/slate/blob/68aff89e892fe15a16314398ff052ade6068900b/packages/slate/src/utils/deep-equal.ts#L13
// We have to match slates deepEquals behavior to merge insert deltas in the same way slate does.
export function deepEquals(
  node: InspectableObject,
  another: InspectableObject
): boolean {
  // eslint-disable-next-line guard-for-in
  for (const key in node) {
    const a = node[key];
    const b = another[key];

    if (isPlainObject(a) && isPlainObject(b)) {
      if (!deepEquals(a, b)) {
        return false;
      }
    } else if (Array.isArray(a) && Array.isArray(b)) {
      if (a.length !== b.length) return false;
      for (let i = 0; i < a.length; i++) {
        if (a[i] !== b[i]) {
          return false;
        }
      }
    } else if (a !== b) {
      return false;
    }
  }

  for (const key in another) {
    if (node[key] === undefined && another[key] !== undefined) {
      return false;
    }
  }

  return true;
}

export function pick<TObj, TKeys extends keyof TObj>(
  obj: TObj,
  ...keys: TKeys[]
): Pick<TObj, TKeys> {
  return Object.fromEntries(
    Object.entries(obj).filter(([key]) => keys.includes(key as TKeys))
  ) as Pick<TObj, TKeys>;
}

export function omit<TObj, TKeys extends keyof TObj>(
  obj: TObj,
  ...keys: TKeys[]
): Omit<TObj, TKeys> {
  return Object.fromEntries(
    Object.entries(obj).filter(([key]) => !keys.includes(key as TKeys))
  ) as Omit<TObj, TKeys>;
}

export function omitNullEntries<TObj>(obj: TObj): {
  [K in keyof TObj]: TObj[K] extends null ? never : K;
} {
  return Object.fromEntries(
    Object.entries(obj).filter(([, value]) => value !== null)
  ) as { [K in keyof TObj]: TObj[K] extends null ? never : K };
}