SERP Settings Sync: Remove KBG flag if feature enabled (#7014)

Task/Issue URL:
https://app.asana.com/1/137249556945/project/72649045549333/task/1211702809875729?focus=true

### Description

Added a conditional check for the `serpSettingsSync` feature flag before
applying the DuckAI SERP hiding logic to ensure when we complete the
rest of the work we're getting the final behaviour we expect and the kbg
param is not inteferring with anyhing.
  
`serpSettingsSync` is now off by default so we do not mess with kbg for
internal users until the rest of the work is complete.

### Steps to test this PR

_KBG Param_

- [x] Ensure Duck.ai is enabled in native settings
- [x] Perform a search e.g. FPL
- [x] Check logs that the search url contains `kbg=-1`​
- [x] Enable `serpSettingsSync`​ feature flag (off by default for now)
- [x] Perform a search e.g. FPL
- [x] Check logs that the search url does **not** contain `kbg=-1`​

### UI changes

N/A

Author: mikescamell

app/src/main/java/com/duckduckgo/app/browser/DuckDuckGoRequestRewriter.kt

@@ -24,6 +24,7 @@ import com.duckduckgo.common.utils.AppUrl.ParamKey
 import com.duckduckgo.common.utils.AppUrl.ParamValue
 import com.duckduckgo.duckchat.api.DuckChat
 import com.duckduckgo.experiments.api.VariantManager
+import com.duckduckgo.settings.api.SettingsPageFeature
 import logcat.logcat
 
 interface RequestRewriter {
@@ -39,6 +40,7 @@ class DuckDuckGoRequestRewriter(
     private val appReferrerDataStore: AppReferrerDataStore,
     private val duckChat: DuckChat,
     private val androidConfigFeatures: AndroidBrowserConfigFeature,
+    private val settingsPageFeature: SettingsPageFeature,
 ) : RequestRewriter {
 
     private val hideDuckAiSerpKillSwitch by lazy { androidConfigFeatures.hideDuckAiInSerpKillSwitch().isEnabled() }
@@ -80,8 +82,11 @@ class DuckDuckGoRequestRewriter(
         val sourceValue = if (appReferrerDataStore.installedFromEuAuction) ParamValue.SOURCE_EU_AUCTION else ParamValue.SOURCE
 
         builder.appendQueryParameter(ParamKey.HIDE_SERP, ParamValue.HIDE_SERP)
-        if (!duckChat.isEnabled() && hideDuckAiSerpKillSwitch) {
-            builder.appendQueryParameter(ParamKey.HIDE_DUCK_AI, ParamValue.HIDE_DUCK_AI)
+        if (!settingsPageFeature.serpSettingsSync().isEnabled()) {
+            // Once serpSettingsSync feature is permanently enabled this can be removed.
+            if (!duckChat.isEnabled() && hideDuckAiSerpKillSwitch) {
+                builder.appendQueryParameter(ParamKey.HIDE_DUCK_AI, ParamValue.HIDE_DUCK_AI)
+            }
         }
         builder.appendQueryParameter(ParamKey.SOURCE, sourceValue)
     }

app/src/main/java/com/duckduckgo/app/browser/di/BrowserModule.kt

@@ -92,6 +92,7 @@ import com.duckduckgo.privacy.config.api.AmpLinks
 import com.duckduckgo.privacy.config.api.Gpc
 import com.duckduckgo.privacy.config.api.TrackingParameters
 import com.duckduckgo.request.filterer.api.RequestFilterer
+import com.duckduckgo.settings.api.SettingsPageFeature
 import com.duckduckgo.subscriptions.api.Subscriptions
 import com.duckduckgo.user.agent.api.UserAgentProvider
 import dagger.Module
@@ -113,8 +114,17 @@ class BrowserModule {
         appReferrerDataStore: AppReferrerDataStore,
         duckChat: DuckChat,
         androidBrowserConfigFeature: AndroidBrowserConfigFeature,
+        settingsPageFeature: SettingsPageFeature,
     ): RequestRewriter {
-        return DuckDuckGoRequestRewriter(urlDetector, statisticsStore, variantManager, appReferrerDataStore, duckChat, androidBrowserConfigFeature)
+        return DuckDuckGoRequestRewriter(
+            urlDetector,
+            statisticsStore,
+            variantManager,
+            appReferrerDataStore,
+            duckChat,
+            androidBrowserConfigFeature,
+            settingsPageFeature,
+        )
     }
 
     @Provides

app/src/test/java/com/duckduckgo/app/browser/DuckDuckGoRequestRewriterTest.kt

@@ -30,6 +30,7 @@ import com.duckduckgo.duckchat.api.DuckChat
 import com.duckduckgo.experiments.api.VariantManager
 import com.duckduckgo.feature.toggles.api.FakeFeatureToggleFactory
 import com.duckduckgo.feature.toggles.api.Toggle.State
+import com.duckduckgo.settings.api.SettingsPageFeature
 import org.junit.Assert.*
 import org.junit.Before
 import org.junit.Test
@@ -46,6 +47,7 @@ class DuckDuckGoRequestRewriterTest {
     private val mockVariantManager: VariantManager = mock()
     private val mockAppReferrerDataStore: AppReferrerDataStore = mock()
     private val duckChat: DuckChat = mock()
+    private val settingsPageFeature: SettingsPageFeature = FakeFeatureToggleFactory.create(SettingsPageFeature::class.java)
     private val androidBrowserConfigFeature: AndroidBrowserConfigFeature = FakeFeatureToggleFactory.create(AndroidBrowserConfigFeature::class.java)
     private lateinit var builder: Uri.Builder
 
@@ -64,6 +66,7 @@ class DuckDuckGoRequestRewriterTest {
             mockAppReferrerDataStore,
             duckChat,
             androidBrowserConfigFeature,
+            settingsPageFeature,
         )
         builder = Uri.Builder()
     }
@@ -152,6 +155,18 @@ class DuckDuckGoRequestRewriterTest {
         assertFalse(uri.queryParameterNames.contains(ParamKey.HIDE_DUCK_AI))
     }
 
+    @Test
+    fun whenSerpSettingsSyncIsEnabledThenDoNotHideDuckAi() {
+        settingsPageFeature.serpSettingsSync().setRawStoredState(State(true))
+        whenever(duckChat.isEnabled()).thenReturn(false)
+        androidBrowserConfigFeature.hideDuckAiInSerpKillSwitch().setRawStoredState(State(true))
+
+        testee.addCustomQueryParams(builder)
+
+        val uri = builder.build()
+        assertFalse(uri.queryParameterNames.contains(ParamKey.HIDE_DUCK_AI))
+    }
+
     @Test
     fun whenShouldRewriteRequestAndUrlIsSerpQueryThenReturnTrue() {
         val uri = "http://duckduckgo.com/?q=weather".toUri()

app/src/test/java/com/duckduckgo/app/browser/QueryUrlConverterTest.kt

@@ -28,6 +28,7 @@ import com.duckduckgo.duckchat.api.DuckChat
 import com.duckduckgo.experiments.api.VariantManager
 import com.duckduckgo.feature.toggles.api.FakeFeatureToggleFactory
 import com.duckduckgo.feature.toggles.api.Toggle.State
+import com.duckduckgo.settings.api.SettingsPageFeature
 import org.junit.Assert.*
 import org.junit.Before
 import org.junit.Test
@@ -43,6 +44,7 @@ class QueryUrlConverterTest {
     private val mockAppReferrerDataStore: AppReferrerDataStore = mock()
     private val duckChat: DuckChat = mock()
     private val androidBrowserConfigFeature: AndroidBrowserConfigFeature = FakeFeatureToggleFactory.create(AndroidBrowserConfigFeature::class.java)
+    private val settingsPageFeature: SettingsPageFeature = FakeFeatureToggleFactory.create(SettingsPageFeature::class.java)
     private val requestRewriter =
         DuckDuckGoRequestRewriter(
             DuckDuckGoUrlDetectorImpl(),
@@ -51,6 +53,7 @@ class QueryUrlConverterTest {
             mockAppReferrerDataStore,
             duckChat,
             androidBrowserConfigFeature,
+            settingsPageFeature,
         )
     private val testee: QueryUrlConverter = QueryUrlConverter(requestRewriter)
 

settings/settings-api/src/main/java/com/duckduckgo/settings/api/SettingsPageFeature.kt

@@ -36,6 +36,5 @@ interface SettingsPageFeature {
     fun hideAiGeneratedImagesOption(): Toggle
 
     @Toggle.DefaultValue(DefaultFeatureValue.FALSE)
-    @Toggle.InternalAlwaysEnabled
     fun serpSettingsSync(): Toggle
 }