fix: Fix set(ArrayBuffer) on Web (#1026)

* fix: Fix `set(ArrayBuffer)` on Web

* chore: Typse

Author: mrousavy

packages/react-native-mmkv/src/createMMKV/createMMKV.web.ts

@@ -1,5 +1,6 @@
 import type { MMKV } from '../specs/MMKV.nitro'
 import type { Configuration } from '../specs/MMKVFactory.nitro'
+import { createTextDecoder } from '../web/createTextDecoder'
 import { createTextEncoder } from '../web/createTextEncoder'
 import {
   getLocalStorage,
@@ -16,6 +17,7 @@ export function createMMKV(
     throw new Error("MMKV: 'path' is not supported on Web!")
   }
 
+  const textDecoder = createTextDecoder()
   const textEncoder = createTextEncoder()
   const listeners = new Set<(key: string) => void>()
 
@@ -71,7 +73,11 @@ export function createMMKV(
     set: (key, value) => {
       const storage = getLocalStorage()
       if (key === '') throw new Error('Cannot set a value for an empty key!')
-      storage.setItem(prefixedKey(key), value.toString())
+      if (value instanceof ArrayBuffer) {
+        storage.setItem(prefixedKey(key), textDecoder.decode(value))
+      } else {
+        storage.setItem(prefixedKey(key), String(value))
+      }
       callListeners(key)
     },
     getString: (key) => {

packages/react-native-mmkv/src/web/createTextDecoder.ts

@@ -0,0 +1,15 @@
+export function createTextDecoder(): TextDecoder {
+  const g = global ?? globalThis ?? window
+  if (g.TextDecoder != null) {
+    return new g.TextDecoder()
+  } else {
+    return {
+      decode: () => {
+        throw new Error('TextDecoder is not supported in this environment!')
+      },
+      encoding: 'utf-8',
+      fatal: false,
+      ignoreBOM: false,
+    }
+  }
+}

packages/react-native-mmkv/src/web/createTextEncoder.ts

@@ -1,4 +1,4 @@
-export function createTextEncoder() {
+export function createTextEncoder(): TextEncoder {
   const g = global ?? globalThis ?? window
   if (g.TextEncoder != null) {
     return new g.TextEncoder()