From 532842c3538094b5418c43e5511cc22322233dab Mon Sep 17 00:00:00 2001
From: oliver-oloughlin <oliveroloughlin@hotmail.com>
Date: Mon, 27 Nov 2023 00:52:04 +0100
Subject: [PATCH] feat: added isObject utility + fixed stringify/parse

---
 json.ts   | 88 +++++++++++++++++++++++++++++++++++++++++++++++++++----
 object.ts | 55 ++++++++++++++++++++++++++++++++++
 2 files changed, 137 insertions(+), 6 deletions(-)

diff --git a/json.ts b/json.ts
index 0c31747..758417a 100644
--- a/json.ts
+++ b/json.ts
@@ -1,3 +1,5 @@
+import { isObject } from "./object.ts"
+
 export type JSONError = {
   message: string
   name: string
@@ -6,6 +8,7 @@ export type JSONError = {
 }
 
 export enum TypeKey {
+  Undefined = "__undefined__",
   BigInt = "__bigint__",
   KvU64 = "__kvu64__",
   Int8Array = "__int8array__",
@@ -29,12 +32,47 @@ export enum TypeKey {
   NaN = "__nan__",
 }
 
+/**
+ * Serialize a value to Uint8Array.
+ *
+ * @param value . Value to be serialized.
+ * @returns Serialized value.
+ */
+export function serialize(value: unknown) {
+  const str = stringify(value)
+  return new TextEncoder().encode(str)
+}
+
+/**
+ * Deserialize a value encoded as Uint8Array.
+ *
+ * @param value - Value to be deserialize.
+ * @returns Deserialized value.
+ */
+export function deserialize<T>(value: Uint8Array) {
+  const str = new TextDecoder().decode(value)
+  return parse<T>(str)
+}
+
+/**
+ * Convert a value to a JSON string.
+ *
+ * @param value - Value to be stringified.
+ * @param space
+ * @returns
+ */
 export function stringify(value: unknown, space?: number | string) {
-  return JSON.stringify(value, replacer, space)
+  return JSON.stringify(_replacer(value), replacer, space)
 }
 
+/**
+ * Parse a value from a JSON string.
+ *
+ * @param value - JSON string to be parsed.
+ * @returns
+ */
 export function parse<T>(value: string) {
-  return JSON.parse(value, reviver) as T
+  return postReviver(JSON.parse(value, reviver)) as T
 }
 
 /**
@@ -44,7 +82,7 @@ export function parse<T>(value: string) {
  * @param value
  * @returns
  */
-export function replacer(_key: string, value: unknown) {
+function replacer(_key: string, value: unknown) {
   return _replacer(value)
 }
 
@@ -55,7 +93,7 @@ export function replacer(_key: string, value: unknown) {
  * @param value
  * @returns
  */
-export function reviver(_key: string, value: unknown) {
+function reviver(_key: string, value: unknown) {
   return _reviver(value)
 }
 
@@ -69,7 +107,6 @@ function _replacer(value: unknown): unknown {
   // Return value if primitive, function or symbol
   if (
     value === null ||
-    value === undefined ||
     typeof value === "string" ||
     typeof value === "number" ||
     typeof value === "function" ||
@@ -78,6 +115,13 @@ function _replacer(value: unknown): unknown {
     return value
   }
 
+  // Undefined
+  if (value === undefined) {
+    return {
+      [TypeKey.Undefined]: false,
+    }
+  }
+
   // NaN
   if (Number.isNaN(value)) {
     return {
@@ -238,7 +282,7 @@ function _replacer(value: unknown): unknown {
   }
 
   // Clone value to handle special cases
-  const clone = structuredClone(value)
+  const clone = structuredClone(value) as Record<string, unknown>
   for (const [k, v] of Object.entries(value)) {
     if (v instanceof Date) {
       clone[k] = _replacer(v)
@@ -385,6 +429,38 @@ function _reviver(value: unknown): unknown {
   return value
 }
 
+/**
+ * Reviver post-parse.
+ *
+ * @param value
+ * @returns
+ */
+function postReviver(value: unknown): unknown {
+  if (
+    value === undefined ||
+    value === null ||
+    typeof value !== "object"
+  ) {
+    return value
+  }
+
+  if (TypeKey.Undefined in value) {
+    return undefined
+  }
+
+  if (Array.isArray(value)) {
+    return value.map((v) => postReviver(v))
+  }
+
+  if (isObject(value)) {
+    return Object.fromEntries(
+      Object.entries(value).map(([k, v]) => [k, postReviver(v)]),
+    )
+  }
+
+  return value
+}
+
 /**
  * Map from special type entry to value.
  *
diff --git a/object.ts b/object.ts
index 22f9733..01e37f5 100644
--- a/object.ts
+++ b/object.ts
@@ -1,3 +1,11 @@
+/**
+ * Remove null and undefined entries from an object.
+ *
+ * If input value is null or undefined, the value is returned as is.
+ *
+ * @param value
+ * @returns
+ */
 export function removeNullish<T>(value: T): NonNullable<T> {
   if (typeof value !== "object") {
     return value!
@@ -15,3 +23,50 @@ export function removeNullish<T>(value: T): NonNullable<T> {
       .map(([key, val]) => [key, removeNullish(val)]),
   ) as NonNullable<T>
 }
+
+/**
+ * Check if value is a basic JS object.
+ *
+ * @param value
+ * @returns
+ */
+export function isObject(value: unknown) {
+  // If value is null or undefined, return false
+  if (value === null || value === undefined) {
+    return false
+  }
+
+  // If value is not an object, return false
+  if (typeof value !== "object") {
+    return false
+  }
+
+  // If value is an instance of other KvValue objects, return false
+  if (
+    value instanceof Deno.KvU64 ||
+    value instanceof Array ||
+    value instanceof Int8Array ||
+    value instanceof Int16Array ||
+    value instanceof Int32Array ||
+    value instanceof BigInt64Array ||
+    value instanceof Uint8Array ||
+    value instanceof Uint16Array ||
+    value instanceof Uint32Array ||
+    value instanceof BigUint64Array ||
+    value instanceof Uint8ClampedArray ||
+    value instanceof Float32Array ||
+    value instanceof Float64Array ||
+    value instanceof ArrayBuffer ||
+    value instanceof Date ||
+    value instanceof Set ||
+    value instanceof Map ||
+    value instanceof RegExp ||
+    value instanceof DataView ||
+    value instanceof Error
+  ) {
+    return false
+  }
+
+  // Return true after performing all checks
+  return true
+}