Extract leetcode webview base class & add md setings listener

Author: Vigilans

src/webview/LeetCodeWebview.ts

@@ -0,0 +1,63 @@
+// Copyright (c) jdneo. All rights reserved.
+// Licensed under the MIT license.
+
+import { ConfigurationChangeEvent, Disposable, ExtensionContext, ViewColumn, WebviewPanel, window, workspace } from "vscode";
+import { markdownEngine } from "./markdownEngine";
+
+export abstract class LeetCodeWebview implements Disposable {
+
+    protected panel: WebviewPanel | undefined;
+    private context: ExtensionContext;
+    private listener: Disposable;
+
+    public initialize(context: ExtensionContext): void {
+        this.context = context;
+        this.listener = workspace.onDidChangeConfiguration((event: ConfigurationChangeEvent) => {
+            if (event.affectsConfiguration("markdown") && this.panel) {
+                this.panel.webview.html = this.getWebviewContent();
+            }
+        }, this);
+    }
+
+    public dispose(): void {
+        this.listener.dispose();
+        if (this.panel) {
+            this.panel.dispose();
+        }
+    }
+
+    protected showWebviewInternal(): this is { panel: WebviewPanel } {
+        if (!this.panel) {
+            const option: ILeetCodeWebviewOption = this.getWebviewOption();
+
+            this.panel = window.createWebviewPanel(option.viewType, option.title, ViewColumn.One, {
+                enableScripts: true,
+                enableCommandUris: true,
+                enableFindWidget: true,
+                retainContextWhenHidden: true,
+                localResourceRoots: markdownEngine.localResourceRoots,
+            });
+
+            this.panel.onDidDispose(() => {
+                this.panel = undefined;
+            }, null, this.context.subscriptions);
+
+            if (option.onDidReceiveMessage) {
+                this.panel.webview.onDidReceiveMessage(option.onDidReceiveMessage, this, this.context.subscriptions);
+            }
+        }
+
+        this.panel.webview.html = this.getWebviewContent();
+        return true;
+    }
+
+    protected abstract getWebviewOption(): ILeetCodeWebviewOption;
+
+    protected abstract getWebviewContent(): string;
+}
+
+export interface ILeetCodeWebviewOption {
+    viewType: string;
+    title: string;
+    onDidReceiveMessage?: (message: any) => Promise<void>;
+}