From 3dcba927922e0eba9f5f7fe44395b60a6dd4eef3 Mon Sep 17 00:00:00 2001
From: Cursor Agent <cursoragent@cursor.com>
Date: Sun, 22 Feb 2026 16:45:43 +0000
Subject: [PATCH] fix(ios): configure analytics for proper active users (DAU)
 counting
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

- Add $lib, $platform, $device_type to all events so PostHog can segment iOS users
- Add $anon_distinct_id to identify call for proper merge of anonymous → identified users
- Add $platform and $lib to person properties on identify for dashboard filtering
- Fallback to default PostHog key when build variable is not substituted (xcconfig)
- Guard against unsubstituted $(VAR) values in analytics payload sends

Co-authored-by: Luiz Henrique <7henrique18@gmail.com>
---
 .../Plotwist/Services/AnalyticsService.swift  | 25 ++++++++++++++-----
 .../Plotwist/Plotwist/Utils/Environment.swift |  2 +-
 2 files changed, 20 insertions(+), 7 deletions(-)

diff --git a/apps/ios/Plotwist/Plotwist/Services/AnalyticsService.swift b/apps/ios/Plotwist/Plotwist/Services/AnalyticsService.swift
index 6076c373..08ea4c95 100644
--- a/apps/ios/Plotwist/Plotwist/Services/AnalyticsService.swift
+++ b/apps/ios/Plotwist/Plotwist/Services/AnalyticsService.swift
@@ -172,11 +172,12 @@ class AnalyticsService {
   }
   
   func identify(userId: String, properties: [String: Any] = [:]) {
+    let previousId = UserDefaults.standard.string(forKey: "analyticsDeviceId")
     UserDefaults.standard.set(userId, forKey: "analyticsUserId")
     #if DEBUG
     print("📊 Analytics: Identified user \(userId)")
     #endif
-    sendIdentify(userId: userId, properties: properties)
+    sendIdentify(userId: userId, previousAnonymousId: previousId, properties: properties)
   }
   
   func reset() {
@@ -194,26 +195,38 @@ class AnalyticsService {
   // MARK: - Private
   
   private func sendEvent(name: String, properties: [String: Any]) {
-    guard !apiKey.isEmpty else { return }
+    guard !apiKey.isEmpty, !apiKey.contains("$(") else { return }
+    var allProperties = properties
+    allProperties["$lib"] = "ios"
+    allProperties["$lib_version"] = Bundle.main.infoDictionary?["CFBundleShortVersionString"] as? String ?? "1.0"
+    allProperties["$platform"] = "iOS"
+    allProperties["$device_type"] = "Mobile"
     Task {
       await sendToPostHog(payload: [
         "api_key": apiKey,
         "event": name,
         "distinct_id": distinctId,
-        "properties": properties,
+        "properties": allProperties,
         "timestamp": ISO8601DateFormatter().string(from: Date()),
       ])
     }
   }
 
-  private func sendIdentify(userId: String, properties: [String: Any]) {
-    guard !apiKey.isEmpty else { return }
+  private func sendIdentify(userId: String, previousAnonymousId: String?, properties: [String: Any]) {
+    guard !apiKey.isEmpty, !apiKey.contains("$(") else { return }
+    var personProperties = properties
+    personProperties["$platform"] = "iOS"
+    personProperties["$lib"] = "ios"
+    var identifyProperties: [String: Any] = ["$set": personProperties]
+    if let previousId = previousAnonymousId, previousId != userId {
+      identifyProperties["$anon_distinct_id"] = previousId
+    }
     Task {
       await sendToPostHog(payload: [
         "api_key": apiKey,
         "event": "$identify",
         "distinct_id": userId,
-        "properties": ["$set": properties],
+        "properties": identifyProperties,
         "timestamp": ISO8601DateFormatter().string(from: Date()),
       ])
     }
diff --git a/apps/ios/Plotwist/Plotwist/Utils/Environment.swift b/apps/ios/Plotwist/Plotwist/Utils/Environment.swift
index e61b0207..0fede88e 100644
--- a/apps/ios/Plotwist/Plotwist/Utils/Environment.swift
+++ b/apps/ios/Plotwist/Plotwist/Utils/Environment.swift
@@ -7,7 +7,7 @@ import Foundation
 
 enum Env {
     static func value(for key: String, fallback: String? = nil) -> String {
-        if let value = Bundle.main.infoDictionary?[key] as? String, !value.isEmpty {
+        if let value = Bundle.main.infoDictionary?[key] as? String, !value.isEmpty, !value.contains("$(") {
             return value.trimmingCharacters(in: .whitespacesAndNewlines)
         }
         print("⚠️ [Env] Missing key: '\(key)' in Info.plist")