feat: google analytics (#15451)

* wip backend

* wip frontend

* build misskey-js

* implement control panel

* fix

* introduce analytics wrapper

* spdx

* Update analytics.ts

* Update common.ts

* wip

* wip

* wip

* wip

* wip

* Update CHANGELOG.md

---------

Co-authored-by: kakkokari-gtyih <67428053+kakkokari-gtyih@users.noreply.github.com>

packages/frontend/src/analytics.ts

@@ -0,0 +1,107 @@
+/*
+ * SPDX-FileCopyrightText: syuilo and misskey-project
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+import * as Misskey from 'misskey-js';
+import type { AnalyticsInstance, AnalyticsPlugin } from 'analytics';
+
+/**
+ * analytics moduleを読み込まなくても動作するようにするためのラッパー
+ */
+class AnalyticsProxy implements AnalyticsInstance {
+	private analytics?: AnalyticsInstance;
+
+	constructor(analytics?: AnalyticsInstance) {
+		if (analytics) {
+			this.analytics = analytics;
+		}
+	}
+
+	public setAnalytics(analytics: AnalyticsInstance) {
+		if (this.analytics) {
+			throw new Error('Analytics instance already exists.');
+		}
+		this.analytics = analytics;
+	}
+
+	public identify(...args: Parameters<AnalyticsInstance['identify']>) {
+		return this.analytics?.identify(...args) ?? Promise.resolve();
+	}
+
+	public track(...args: Parameters<AnalyticsInstance['track']>) {
+		return this.analytics?.track(...args) ?? Promise.resolve();
+	}
+
+	public page(...args: Parameters<AnalyticsInstance['page']>) {
+		return this.analytics?.page(...args) ?? Promise.resolve();
+	}
+
+	public user(...args: Parameters<AnalyticsInstance['user']>) {
+		return this.analytics?.user(...args) ?? Promise.resolve();
+	}
+
+	public reset(...args: Parameters<AnalyticsInstance['reset']>) {
+		return this.analytics?.reset(...args) ?? Promise.resolve();
+	}
+
+	public ready(...args: Parameters<AnalyticsInstance['ready']>) {
+		return this.analytics?.ready(...args) ?? function () { void 0; };
+	}
+
+	public on(...args: Parameters<AnalyticsInstance['on']>) {
+		return this.analytics?.on(...args) ?? function () { void 0; };
+	}
+
+	public once(...args: Parameters<AnalyticsInstance['once']>) {
+		return this.analytics?.once(...args) ?? function () { void 0; };
+	}
+
+	public getState(...args: Parameters<AnalyticsInstance['getState']>) {
+		return this.analytics?.getState(...args) ?? Promise.resolve();
+	}
+
+	public get storage() {
+		return this.analytics?.storage ?? {
+			getItem: () => null,
+			setItem: () => void 0,
+			removeItem: () => void 0,
+		};
+	}
+
+	public get plugins() {
+		return this.analytics?.plugins ?? {
+			enable: (p, c) => Promise.resolve(c ? c() : void 0),
+			disable: (p, c) => Promise.resolve(c ? c() : void 0),
+		};
+	}
+}
+
+export const analytics = new AnalyticsProxy();
+
+export async function initAnalytics(instance: Misskey.entities.MetaDetailed) {
+	// アナリティクスプロバイダに関する設定がひとつもない場合は、アナリティクスモジュールを読み込まない
+	if (!instance.googleAnalyticsMeasurementId) {
+		return;
+	}
+
+	const { default: Analytics } = await import('analytics');
+	const plugins: AnalyticsPlugin[] = [];
+
+	// Google Analytics
+	if (instance.googleAnalyticsMeasurementId) {
+		const { default: googleAnalytics } = await import('@analytics/google-analytics');
+
+		plugins.push(googleAnalytics({
+			measurementIds: [instance.googleAnalyticsMeasurementId],
+			debug: _DEV_,
+		}));
+	}
+
+	analytics.setAnalytics(Analytics({
+		app: 'misskey',
+		version: _VERSION_,
+		debug: _DEV_,
+		plugins,
+	}));
+}