From da6ca76304f61ba3c0d26f70a43f2c9addcd8199 Mon Sep 17 00:00:00 2001
From: Henrique Bruno <henrique.bruno.fa@gmail.com>
Date: Sat, 26 Dec 2020 04:23:06 -0300
Subject: [PATCH] added reset()

---
 src/async.ts       | 37 +++++++++++++++++++++++++++++++++++++
 src/parse-store.ts | 41 ++++++++++++++++++++---------------------
 2 files changed, 57 insertions(+), 21 deletions(-)

diff --git a/src/async.ts b/src/async.ts
index 6b66731..ddcd953 100644
--- a/src/async.ts
+++ b/src/async.ts
@@ -48,6 +48,14 @@ export interface AsyncTrunkOptions {
    * @param error
    */
   onError?: (error: any) => void;
+
+  /**
+   * If the values of non-ignored properties before the trunk.init() should be
+   * volatilly saved so they can be later `reset()`ed.
+   *
+   * Defaults to `false`.
+   */
+  saveDefaultValues?: boolean;
 }
 
 export class AsyncTrunk {
@@ -58,6 +66,9 @@ export class AsyncTrunk {
   readonly delay: number;
   readonly onError: (error: any) => void;
 
+  readonly saveDefaultValues: boolean;
+  private defaultValues: any;
+
   constructor(
     store: any,
     {
@@ -65,6 +76,7 @@ export class AsyncTrunk {
       storageKey = KeyDefaultKey,
       delay = 0,
       onError = noop,
+      saveDefaultValues = false,
     }: AsyncTrunkOptions = {},
   ) {
     this.store = store;
@@ -72,6 +84,7 @@ export class AsyncTrunk {
     this.storageKey = storageKey;
     this.delay = delay;
     this.onError = onError;
+    this.saveDefaultValues = saveDefaultValues;
   }
 
   async persist() {
@@ -104,8 +117,32 @@ export class AsyncTrunk {
       delay: this.delay,
       onError: this.onError,
     });
+    // Save default values
+    if (this.saveDefaultValues)
+      parseStore(this.store, initialState, false, this.defaultValues);
   }
 
+  /**
+   * It will reset the store properties to their default values and also save on storage.
+   *
+   * You must have set the `saveDefaultValues` parameter in this trunk constructor.
+   */
+  async reset() {
+    if (!this.saveDefaultValues) {
+      this.onError(
+        "mobx-sync reset() was called but saveDefaultValues parameter wasn't set on the trunk constructor.",
+      );
+      return;
+    }
+
+    parseStore(
+      this.store,
+      JSON.parse(JSON.stringify(this.defaultValues)),
+      false,
+    );
+    return this.persist();
+  }
+  /** Erases the data from the storage. */
   async clear() {
     return this.storage.removeItem(this.storageKey);
   }
diff --git a/src/parse-store.ts b/src/parse-store.ts
index 31f2ebf..0b7c9b1 100644
--- a/src/parse-store.ts
+++ b/src/parse-store.ts
@@ -12,7 +12,13 @@ import { action, isObservableArray, isObservableMap, observable } from 'mobx';
 import { KeyFormat, KeyNodeVersion, KeyVersions } from './keys';
 import { isPrimitive } from './utils';
 
-let parseStore = (store: any, data: any, isFromServer: boolean) => {
+/** Target allows saving the current data elsewhere than the store itself */
+let parseStore = (
+  store: any,
+  data: any,
+  isFromServer: boolean,
+  target: any = store,
+) => {
   // if store or data is empty, break it
   if (!store || !data) {
     return;
@@ -21,10 +27,8 @@ let parseStore = (store: any, data: any, isFromServer: boolean) => {
   const storeVersions = store[KeyVersions] || {};
   const deserializers = store[KeyFormat] || {};
   // version control for node
-  if ((KeyNodeVersion in dataVersions)
-    || (KeyNodeVersion in storeVersions)) {
-    if (dataVersions[KeyNodeVersion]
-      !== storeVersions[KeyNodeVersion]) {
+  if (KeyNodeVersion in dataVersions || KeyNodeVersion in storeVersions) {
+    if (dataVersions[KeyNodeVersion] !== storeVersions[KeyNodeVersion]) {
       return;
     }
   }
@@ -52,27 +56,22 @@ let parseStore = (store: any, data: any, isFromServer: boolean) => {
       const storeValue = store[key];
       const dataValue = data[key];
       if (deserializers[key] && deserializers[key].deserializer) {
-        store[key] = deserializers[key].deserializer(dataValue, storeValue);
-      }
-      else if (isObservableArray(storeValue)) {
+        target[key] = deserializers[key].deserializer(dataValue, storeValue);
+      } else if (isObservableArray(storeValue)) {
         // mobx array
-        store[key] = observable.array(dataValue);
-      }
-      else if (isObservableMap(storeValue)) {
+        target[key] = observable.array(dataValue);
+      } else if (isObservableMap(storeValue)) {
         // mobx map
-        store[key] = observable.map(dataValue);
-      }
-      else if (isPrimitive(dataValue)) {
+        target[key] = observable.map(dataValue);
+      } else if (isPrimitive(dataValue)) {
         // js/mobx primitive objects
-        store[key] = dataValue;
-      }
-      else if (!storeValue) {
+        target[key] = dataValue;
+      } else if (!storeValue) {
         // if store value is empty, assign persisted data to it directly
-        store[key] = dataValue;
-      }
-      else {
+        target[key] = dataValue;
+      } else {
         // nested pure js object or mobx observable object
-        parseStore(storeValue, dataValue, isFromServer);
+        parseStore(storeValue, dataValue, isFromServer, target[key]);
       }
     }
   }