feat(analytics): Firebase Analytics, Crashlytics, ObservabilityModule, Firestore rules

app/build.gradle.kts

@@ -73,6 +73,9 @@ dependencies {
     implementation("com.google.firebase:firebase-config-ktx")
     implementation("com.google.firebase:firebase-analytics-ktx")
     implementation("com.google.firebase:firebase-crashlytics-ktx")
+    implementation("com.google.firebase:firebase-appcheck-ktx")
+    implementation("com.google.firebase:firebase-appcheck-playintegrity")
+    debugImplementation("com.google.firebase:firebase-appcheck-debug")
 
     // Hilt
     implementation("com.google.dagger:hilt-android:2.53.1")

app/src/main/java/com/couplesconnect/app/App.kt

@@ -1,12 +1,17 @@
 package com.couplesconnect.app
 
 import android.app.Application
+import com.couplesconnect.app.core.firebase.FirebaseInitializer
 import dagger.hilt.android.HiltAndroidApp
+import javax.inject.Inject
 
 @HiltAndroidApp
 class CouplesConnectApp : Application() {
+
+    @Inject lateinit var firebaseInitializer: FirebaseInitializer
+
     override fun onCreate() {
         super.onCreate()
-        // Initialize app-wide components here
+        firebaseInitializer.initialize()
     }
 }

app/src/main/java/com/couplesconnect/app/core/analytics/AnalyticsTracker.kt

@@ -0,0 +1,16 @@
+package com.couplesconnect.app.core.analytics
+
+interface AnalyticsTracker {
+    fun trackScreenViewed(screenName: String)
+    fun trackAppOpened()
+    fun trackQuestionViewed(questionId: String, category: String)
+    fun trackAnswerSubmitted(questionId: String, category: String, answerType: String)
+    fun trackAnswerRevealed(questionId: String, category: String)
+    fun trackPaywallViewed(source: String)
+    fun trackCouplePaired()
+    fun trackCoupleLeft()
+    fun trackSpinWheelStarted(categoryId: String)
+    fun trackSpinWheelCompleted(categoryId: String, answeredCount: Int)
+    fun trackSignIn(method: String)
+    fun trackSignUp(method: String)
+}

app/src/main/java/com/couplesconnect/app/core/analytics/FirebaseAnalyticsTracker.kt

@@ -0,0 +1,84 @@
+package com.couplesconnect.app.core.analytics
+
+import android.os.Bundle
+import com.google.firebase.analytics.FirebaseAnalytics
+import com.google.firebase.analytics.logEvent
+import javax.inject.Inject
+import javax.inject.Singleton
+
+@Singleton
+class FirebaseAnalyticsTracker @Inject constructor(
+    private val analytics: FirebaseAnalytics
+) : AnalyticsTracker {
+
+    override fun trackScreenViewed(screenName: String) {
+        analytics.logEvent(FirebaseAnalytics.Event.SCREEN_VIEW) {
+            param(FirebaseAnalytics.Param.SCREEN_NAME, screenName)
+        }
+    }
+
+    override fun trackAppOpened() {
+        analytics.logEvent("app_opened", Bundle.EMPTY)
+    }
+
+    override fun trackQuestionViewed(questionId: String, category: String) {
+        analytics.logEvent("question_viewed") {
+            param("question_id", questionId)
+            param("category", category)
+        }
+    }
+
+    override fun trackAnswerSubmitted(questionId: String, category: String, answerType: String) {
+        analytics.logEvent("answer_submitted") {
+            param("question_id", questionId)
+            param("category", category)
+            param("answer_type", answerType)
+        }
+    }
+
+    override fun trackAnswerRevealed(questionId: String, category: String) {
+        analytics.logEvent("answer_revealed") {
+            param("question_id", questionId)
+            param("category", category)
+        }
+    }
+
+    override fun trackPaywallViewed(source: String) {
+        analytics.logEvent("paywall_viewed") {
+            param("source", source)
+        }
+    }
+
+    override fun trackCouplePaired() {
+        analytics.logEvent("couple_paired", Bundle.EMPTY)
+    }
+
+    override fun trackCoupleLeft() {
+        analytics.logEvent("couple_left", Bundle.EMPTY)
+    }
+
+    override fun trackSpinWheelStarted(categoryId: String) {
+        analytics.logEvent("spin_wheel_started") {
+            param("category_id", categoryId)
+        }
+    }
+
+    override fun trackSpinWheelCompleted(categoryId: String, answeredCount: Int) {
+        analytics.logEvent("spin_wheel_completed") {
+            param("category_id", categoryId)
+            param("answered_count", answeredCount.toLong())
+        }
+    }
+
+    override fun trackSignIn(method: String) {
+        analytics.logEvent(FirebaseAnalytics.Event.LOGIN) {
+            param(FirebaseAnalytics.Param.METHOD, method)
+        }
+    }
+
+    override fun trackSignUp(method: String) {
+        analytics.logEvent(FirebaseAnalytics.Event.SIGN_UP) {
+            param(FirebaseAnalytics.Param.METHOD, method)
+        }
+    }
+}

app/src/main/java/com/couplesconnect/app/core/crash/CrashReporter.kt

@@ -0,0 +1,8 @@
+package com.couplesconnect.app.core.crash
+
+interface CrashReporter {
+    fun setUserId(uid: String)
+    fun clearUserId()
+    fun log(message: String)
+    fun recordException(throwable: Throwable)
+}

app/src/main/java/com/couplesconnect/app/core/crash/FirebaseCrashReporter.kt

@@ -0,0 +1,27 @@
+package com.couplesconnect.app.core.crash
+
+import com.google.firebase.crashlytics.FirebaseCrashlytics
+import javax.inject.Inject
+import javax.inject.Singleton
+
+@Singleton
+class FirebaseCrashReporter @Inject constructor() : CrashReporter {
+
+    private val crashlytics = FirebaseCrashlytics.getInstance()
+
+    override fun setUserId(uid: String) {
+        crashlytics.setUserId(uid)
+    }
+
+    override fun clearUserId() {
+        crashlytics.setUserId("")
+    }
+
+    override fun log(message: String) {
+        crashlytics.log(message)
+    }
+
+    override fun recordException(throwable: Throwable) {
+        crashlytics.recordException(throwable)
+    }
+}

app/src/main/java/com/couplesconnect/app/core/firebase/FirebaseInitializer.kt

@@ -0,0 +1,35 @@
+package com.couplesconnect.app.core.firebase
+
+import com.couplesconnect.app.BuildConfig
+import com.google.firebase.appcheck.FirebaseAppCheck
+import com.google.firebase.appcheck.playintegrity.PlayIntegrityAppCheckProviderFactory
+import javax.inject.Inject
+import javax.inject.Singleton
+
+@Singleton
+class FirebaseInitializer @Inject constructor() {
+
+    fun initialize() {
+        val appCheck = FirebaseAppCheck.getInstance()
+        if (BuildConfig.DEBUG) {
+            // DebugAppCheckProviderFactory is in the debug artifact only;
+            // referenced by name to avoid a compile-time dep in release.
+            try {
+                val cls = Class.forName(
+                    "com.google.firebase.appcheck.debug.DebugAppCheckProviderFactory"
+                )
+                val factory = cls.getMethod("getInstance").invoke(null)
+                    as com.google.firebase.appcheck.AppCheckProviderFactory
+                appCheck.installAppCheckProviderFactory(factory)
+            } catch (_: Exception) {
+                appCheck.installAppCheckProviderFactory(
+                    PlayIntegrityAppCheckProviderFactory.getInstance()
+                )
+            }
+        } else {
+            appCheck.installAppCheckProviderFactory(
+                PlayIntegrityAppCheckProviderFactory.getInstance()
+            )
+        }
+    }
+}

app/src/main/java/com/couplesconnect/app/di/ObservabilityModule.kt

@@ -0,0 +1,32 @@
+package com.couplesconnect.app.di
+
+import android.content.Context
+import com.couplesconnect.app.core.analytics.AnalyticsTracker
+import com.couplesconnect.app.core.analytics.FirebaseAnalyticsTracker
+import com.couplesconnect.app.core.crash.CrashReporter
+import com.couplesconnect.app.core.crash.FirebaseCrashReporter
+import com.google.firebase.analytics.FirebaseAnalytics
+import dagger.Binds
+import dagger.Module
+import dagger.Provides
+import dagger.hilt.InstallIn
+import dagger.hilt.android.qualifiers.ApplicationContext
+import dagger.hilt.components.SingletonComponent
+import javax.inject.Singleton
+
+@Module
+@InstallIn(SingletonComponent::class)
+abstract class ObservabilityModule {
+
+    @Binds @Singleton
+    abstract fun bindAnalyticsTracker(impl: FirebaseAnalyticsTracker): AnalyticsTracker
+
+    @Binds @Singleton
+    abstract fun bindCrashReporter(impl: FirebaseCrashReporter): CrashReporter
+
+    companion object {
+        @Provides @Singleton
+        fun provideFirebaseAnalytics(@ApplicationContext context: Context): FirebaseAnalytics =
+            FirebaseAnalytics.getInstance(context)
+    }
+}

firestore.rules

@@ -0,0 +1,69 @@
+rules_version = '2';
+service cloud.firestore {
+  match /databases/{database}/documents {
+
+    // ── Helpers ──────────────────────────────────────────────────────────────
+
+    function isSignedIn() {
+      return request.auth != null;
+    }
+
+    function isOwner(uid) {
+      return isSignedIn() && request.auth.uid == uid;
+    }
+
+    function isCouplesMember(coupleId) {
+      return isSignedIn()
+        && request.auth.uid in
+           get(/databases/$(database)/documents/couples/$(coupleId)).data.userIds;
+    }
+
+    // ── Users ─────────────────────────────────────────────────────────────────
+    // Each user owns exactly their own document.
+
+    match /users/{uid} {
+      allow read, write: if isOwner(uid);
+    }
+
+    // ── Invite codes ──────────────────────────────────────────────────────────
+    // Any authenticated user can create or read an invite code.
+    // Only status + acceptor fields may be updated (no re-writing the code).
+
+    match /invites/{code} {
+      allow read:   if isSignedIn();
+      allow create: if isSignedIn();
+      allow update: if isSignedIn()
+        && resource.data.status == 'pending'
+        && request.resource.data.keys().hasOnly(
+             ['status', 'acceptorUserId', 'acceptedAt', 'coupleId']);
+    }
+
+    // ── Couples ───────────────────────────────────────────────────────────────
+    // Only the two members of a couple may read or write couple data.
+
+    match /couples/{coupleId} {
+      allow read, write: if isCouplesMember(coupleId);
+
+      // Question threads live under the couple document.
+      match /question_threads/{threadId} {
+        allow read, write: if isCouplesMember(coupleId);
+
+        // Answers: each user writes their own; both members can read all answers.
+        match /answers/{userId} {
+          allow write:  if isOwner(userId);
+          allow read:   if isCouplesMember(coupleId);
+        }
+
+        // Discussion messages: any couple member can write and read.
+        match /messages/{messageId} {
+          allow read, write: if isCouplesMember(coupleId);
+        }
+
+        // Reactions: any couple member can write and read.
+        match /reactions/{reactionId} {
+          allow read, write: if isCouplesMember(coupleId);
+        }
+      }
+    }
+  }
+}