feat: analytics interface in :common

common/src/main/java/com/ichi2/anki/common/analytics/Analytics.kt

@@ -0,0 +1,92 @@
+/*
+ * Copyright (c) 2026 Ashish Yadav <mailtoashish693@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License as published by the Free Software
+ * Foundation; either version 3 of the License, or (at your option) any later
+ * version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT ANY
+ * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
+ * PARTICULAR PURPOSE. See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+package com.ichi2.anki.common.analytics
+
+import androidx.annotation.VisibleForTesting
+
+/**
+ * Interface for analytics tracking.
+ *
+ * Implemented in the app module (e.g. by `AnkiDroidUsageAnalytics`).
+ * Feature modules should use [Analytics] object to send events.
+ */
+interface UsageAnalytics {
+    /**
+     * Send a detailed arbitrary analytics event, with noun/verb pairs and extra data if needed.
+     *
+     * @param category the category of event, make your own but use a constant so reporting is good
+     * @param action   the action the user performed
+     * @param value    a value for the event
+     * @param label    a label for the event
+     */
+    fun sendAnalyticsEvent(
+        category: String,
+        action: String,
+        value: Int? = null,
+        label: String? = null,
+    )
+
+    /**
+     * Submit a screen for aggregation / analysis.
+     * Intended for use to determine if / how features are being used.
+     *
+     * @param screen the result of [Class.getSimpleName] will be used as the screen tag
+     */
+    fun sendAnalyticsScreenView(screen: Any) {
+        sendAnalyticsScreenView(screen.javaClass.simpleName)
+    }
+
+    /**
+     * Submit a screen display with a synthetic name for aggregation / analysis.
+     * Intended for use if your class handles multiple screens you want to track separately.
+     *
+     * @param screenName the name to show in analysis reports
+     */
+    fun sendAnalyticsScreenView(screenName: String)
+}
+
+/**
+ * Global accessor for analytics. Delegates to the [UsageAnalytics] implementation
+ * set during app initialization.
+ *
+ * Usage:
+ * ```
+ * Analytics.sendAnalyticsEvent("Widget", "enabled")
+ * Analytics.sendAnalyticsScreenView("DeckPicker")
+ * ```
+ */
+object Analytics {
+    lateinit var instance: UsageAnalytics
+        private set
+
+    fun setAnalytics(analytics: UsageAnalytics) {
+        instance = analytics
+    }
+
+    @VisibleForTesting
+    fun getAnalytics(): UsageAnalytics = instance
+
+    fun sendAnalyticsEvent(
+        category: String,
+        action: String,
+        value: Int? = null,
+        label: String? = null,
+    ) = instance.sendAnalyticsEvent(category, action, value, label)
+
+    fun sendAnalyticsScreenView(screen: Any) = instance.sendAnalyticsScreenView(screen)
+
+    fun sendAnalyticsScreenView(screenName: String) = instance.sendAnalyticsScreenView(screenName)
+}