Add difficulty badge to problems in explorer tree

package.json

@@ -671,6 +671,12 @@
                         "default": "node",
                         "scope": "application",
                         "description": "The Node.js executable path. for example, C:\\Program Files\\nodejs\\node.exe"
+                    },
+                    "leetcode.colorizeProblems": {
+                        "type": "boolean",
+                        "default": false,
+                        "scope": "application",
+                        "description": "Add difficulty badge and colorize problems files in explorer tree."
                     }
                 }
             }
@@ -689,7 +695,7 @@
         "@types/mocha": "^2.2.42",
         "@types/node": "^14.14.33",
         "@types/require-from-string": "^1.2.0",
-        "@types/vscode": "^1.56.0",
+        "@types/vscode": "1.56.0",
         "tslint": "^5.20.1",
         "typescript": "^4.3.2"
     },

src/explorer/LeetCodeTreeItemDecorationProvider.ts

@@ -1,5 +1,5 @@
 import { URLSearchParams } from "url";
-import { FileDecoration, FileDecorationProvider, ProviderResult, ThemeColor, Uri } from "vscode";
+import { FileDecoration, FileDecorationProvider, ProviderResult, ThemeColor, Uri, workspace, WorkspaceConfiguration } from "vscode";
 
 export class LeetCodeTreeItemDecorationProvider implements FileDecorationProvider {
     private readonly DIFFICULTY_BADGE_LABEL: { [key: string]: string } = {
@@ -15,6 +15,10 @@ export class LeetCodeTreeItemDecorationProvider implements FileDecorationProvide
     };
 
     public provideFileDecoration(uri: Uri): ProviderResult<FileDecoration>  {
+        if (!this.isDifficultyBadgeEnabled()) {
+            return;
+        }
+
         if (uri.scheme !== "leetcode" && uri.authority !== "problems") {
             return;
         }
@@ -26,6 +30,11 @@ export class LeetCodeTreeItemDecorationProvider implements FileDecorationProvide
             color: this.ITEM_COLOR[difficulty],
         };
     }
+
+    private isDifficultyBadgeEnabled(): boolean {
+        const configuration: WorkspaceConfiguration = workspace.getConfiguration();
+        return configuration.get<boolean>("leetcode.colorizeProblems", false);
+    }
 }
 
 export const leetCodeTreeItemDecorationProvider: LeetCodeTreeItemDecorationProvider = new LeetCodeTreeItemDecorationProvider();