diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index db9d869..bf52c8f 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -668,12 +668,48 @@ importers:
 
   src:
     dependencies:
+      '@motajs/animate':
+        specifier: workspace:*
+        version: link:../packages/animate
+      '@motajs/anon-tokyo':
+        specifier: workspace:*
+        version: link:../packages/anon-tokyo
+      '@motajs/audio':
+        specifier: workspace:*
+        version: link:../packages/audio
+      '@motajs/common':
+        specifier: workspace:*
+        version: link:../packages/common
+      '@motajs/loader':
+        specifier: workspace:*
+        version: link:../packages/loader
+      '@motajs/render':
+        specifier: workspace:*
+        version: link:../packages/render
+      '@motajs/render-vue':
+        specifier: workspace:*
+        version: link:../packages/render-vue
+      '@motajs/system':
+        specifier: workspace:*
+        version: link:../packages/system
+      '@user/client-base':
+        specifier: workspace:*
+        version: link:../packages-user/client-base
+      '@user/client-modules':
+        specifier: workspace:*
+        version: link:../packages-user/client-modules
+      '@user/data-base':
+        specifier: workspace:*
+        version: link:../packages-user/data-base
       '@user/data-common':
         specifier: workspace:*
         version: link:../packages-user/data-common
       '@user/data-state':
         specifier: workspace:*
         version: link:../packages-user/data-state
+      '@user/data-system':
+        specifier: workspace:*
+        version: link:../packages-user/data-system
 
 packages:
 
diff --git a/src/data/plugin/shop/state.ts b/src/data/plugin/shop/state.ts
index 161d72e..013ca3c 100644
--- a/src/data/plugin/shop/state.ts
+++ b/src/data/plugin/shop/state.ts
@@ -77,9 +77,9 @@ export class ShopState implements IShopState {
         return {
             id: this.id,
             enabled: this.enabled,
-            items: this.items,
-            buyPrice: this.buyPrice,
-            sellPrice: this.sellPrice
+            items: new Map(this.items),
+            buyPrice: new Map(this.buyPrice),
+            sellPrice: new Map(this.sellPrice)
         };
     }
 
diff --git a/src/data/plugin/shop/system.ts b/src/data/plugin/shop/system.ts
index 95ecc7d..b8a52b2 100644
--- a/src/data/plugin/shop/system.ts
+++ b/src/data/plugin/shop/system.ts
@@ -45,6 +45,9 @@ export class ShopSystem implements IShopSystem {
 
     @shouldReplay('Buying items should be replayed.')
     buyItem(item: number | string, count: number): ShopTradeResult {
+        if (count < 0) return this.sellItem(item, -count);
+        if (count === 0) return ShopTradeResult.Success;
+        if (!Number.isInteger(count)) return ShopTradeResult.Invalid;
         if (!this.current || !this.hero) {
             logger.warn(199);
             return ShopTradeResult.Invalid;
@@ -76,7 +79,11 @@ export class ShopSystem implements IShopSystem {
         return ShopTradeResult.Success;
     }
 
+    @shouldReplay('Selling items should be replayed.')
     sellItem(item: number | string, count: number): ShopTradeResult {
+        if (count < 0) return this.buyItem(item, -count);
+        if (count === 0) return ShopTradeResult.Success;
+        if (!Number.isInteger(count)) return ShopTradeResult.Invalid;
         if (!this.current || !this.hero) {
             logger.warn(199);
             return ShopTradeResult.Invalid;