support setting the default language preference

Author: sheche@microsoft.com

package.json

@@ -118,7 +118,41 @@
                     "when": "never"
                 }
             ]
-        }
+        },
+        "configuration": [
+            {
+                "title": "LeetCode",
+                "properties": {
+                    "leetcode.defaultLanguage": {
+                        "type": "string",
+                        "enum": [
+                            "bash",
+                            "c",
+                            "cpp",
+                            "csharp",
+                            "golang",
+                            "java",
+                            "javascript",
+                            "kotlin",
+                            "mysql",
+                            "python",
+                            "python3",
+                            "ruby",
+                            "scala",
+                            "swift"
+                        ],
+                        "scope": "window",
+                        "description": "Default language preference for solving the problems."
+                    },
+                    "leetcode.showSetDefaultLanguageHint": {
+                        "type": "boolean",
+                        "default": true,
+                        "scope": "window",
+                        "description": "Show a hint to let user set the default language preference."
+                    }
+                }
+            }
+        ]
     },
     "scripts": {
         "vscode:prepublish": "npm run compile",

src/commands/show.ts

@@ -6,7 +6,7 @@ import { LeetCodeNode } from "../leetCodeExplorer";
 import { leetCodeManager } from "../leetCodeManager";
 import { IQuickItemEx, languages, leetCodeBinaryPath } from "../shared";
 import { executeCommand } from "../utils/cpUtils";
-import { DialogType, promptForOpenOutputChannel, promptForSignIn } from "../utils/uiUtils";
+import { DialogOptions, DialogType, promptForOpenOutputChannel, promptForSignIn } from "../utils/uiUtils";
 import { selectWorkspaceFolder } from "../utils/workspaceUtils";
 import * as list from "./list";
 
@@ -37,10 +37,25 @@ export async function searchProblem(channel: vscode.OutputChannel): Promise<void
 
 async function showProblemInternal(channel: vscode.OutputChannel, id: string): Promise<void> {
     try {
-        const language: string | undefined = await vscode.window.showQuickPick(languages, { placeHolder: "Select the language you want to use" });
+        const leetCodeConfig: vscode.WorkspaceConfiguration = vscode.workspace.getConfiguration("leetcode");
+        const defaultLanguage = leetCodeConfig.get<string>("defaultLanguage");
+        const language: string | undefined = defaultLanguage || await vscode.window.showQuickPick(languages, { placeHolder: "Select the language you want to use" });
         if (!language) {
             return;
         }
+        if (!defaultLanguage && leetCodeConfig.get<boolean>("showSetDefaultLanguageHint")) {
+            const choice: vscode.MessageItem | undefined = await vscode.window.showInformationMessage(
+                `Would you like to set '${language}' as your default language?`,
+                DialogOptions.yes,
+                DialogOptions.no,
+                DialogOptions.never,
+            );
+            if (choice === DialogOptions.yes) {
+                leetCodeConfig.update("defaultLanguage", language, true /* UserSetting */);
+            } else if (choice === DialogOptions.never) {
+                leetCodeConfig.update("showSetDefaultLanguageHint", false, true /* UserSetting */);
+            }
+        }
         const outdir: string = await selectWorkspaceFolder();
         await fse.ensureDir(outdir);
         const result: string = await executeCommand(channel, "node", [leetCodeBinaryPath, "show", id, "-gx", "-l", language, "-o", outdir]);

src/utils/uiUtils.ts

@@ -7,6 +7,7 @@ export namespace DialogOptions {
     export const open: vscode.MessageItem = { title: "Open" };
     export const yes: vscode.MessageItem = { title: "Yes" };
     export const no: vscode.MessageItem = { title: "No", isCloseAffordance: true };
+    export const never: vscode.MessageItem = { title: "Never" };
     export const singUp: vscode.MessageItem = { title: "Sign up" };
 }