Fix #8674: Add default browser P3A

Sources/Brave/Frontend/Browser/BrowserViewController/BVC+P3A.swift

@@ -14,6 +14,30 @@ import os.log
 
 extension BrowserViewController {
 
+  func recordDefaultBrowserLikelyhoodP3A(openedHTTPLink: Bool = false) {
+    let isInstalledInThePastWeek: Bool = {
+      guard let installDate = Preferences.DAU.installationDate.value else {
+        // Pref is removed after 14 days
+        return false
+      }
+      return Date.now.timeIntervalSince(installDate) <= 7.days
+    }()
+    enum Answer: Int, CaseIterable {
+      case notEnoughInfo = 0
+      case no = 1
+      case yes = 2
+    }
+    let isLikelyDefault = DefaultBrowserHelper.isBraveLikelyDefaultBrowser()
+    let answer: Answer = {
+      if !openedHTTPLink, isInstalledInThePastWeek {
+        // Hasn't been at least 7 days
+        return .notEnoughInfo
+      }
+      return isLikelyDefault ? .yes : .no
+    }()
+    UmaHistogramEnumeration("Brave.IOS.DefaultBrowser", sample: answer)
+  }
+
   func maybeRecordInitialShieldsP3A() {
     if Preferences.Shields.initialP3AStateReported.value { return }
     defer { Preferences.Shields.initialP3AStateReported.value = true }

Sources/Brave/Frontend/Browser/BrowserViewController/BrowserViewController.swift

@@ -572,6 +572,7 @@ public class BrowserViewController: UIViewController {
     recordGeneralBottomBarLocationP3A()
     PlaylistP3A.recordHistogram()
     recordAdsUsageType()
+    recordDefaultBrowserLikelyhoodP3A()
 
     // Revised Review Handling
     AppReviewManager.shared.handleAppReview(for: .revisedCrossPlatform, using: self)
@@ -3153,6 +3154,9 @@ extension BrowserViewController {
     // in case an external url is triggered
     if case .url(let navigatedURL, _) = path {
       if navigatedURL?.isWebPage(includeDataURIs: false) == true {
+        Preferences.General.lastHTTPURLOpenedDate.value = .now
+        recordDefaultBrowserLikelyhoodP3A(openedHTTPLink: true)
+
         Preferences.General.defaultBrowserCalloutDismissed.value = true
         Preferences.DefaultBrowserIntro.defaultBrowserNotificationScheduled.value = true
 

Sources/Brave/Frontend/ClientPreferences.swift

@@ -84,6 +84,9 @@ extension Preferences {
     static var defaultPageZoomLevel = Option<Double>(key: "general.default-page-zoom-level", default: 1.0)
 
     static let isUsingBottomBar = Option<Bool>(key: "general.bottom-bar", default: false)
+
+    /// The last time the app opened and handed a http or https url
+    static let lastHTTPURLOpenedDate = Option<Date?>(key: "general.last-url-opened-date", default: nil)
   }
 
   final public class Search {

Sources/Brave/Helpers/DefaultBrowserHelper.swift

@@ -0,0 +1,15 @@
+// Copyright 2024 The Brave Authors. All rights reserved.
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at https://mozilla.org/MPL/2.0/.
+
+import Foundation
+import Preferences
+
+enum DefaultBrowserHelper {
+  /// Whether or not its likely that Brave is the users default browser based on a 14 day usage period
+  static func isBraveLikelyDefaultBrowser() -> Bool {
+    guard let date = Preferences.General.lastHTTPURLOpenedDate.value else { return false }
+    return date >= Date.now.addingTimeInterval(-14.days)
+  }
+}

Tests/ClientTests/DefaultBrowserHelperTests.swift

@@ -0,0 +1,42 @@
+// Copyright 2024 The Brave Authors. All rights reserved.
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at https://mozilla.org/MPL/2.0/.
+
+import Foundation
+@testable import Brave
+import XCTest
+import Preferences
+
+class DefaultBrowserHelperTests: XCTestCase {
+  override func setUp() async throws {
+    Preferences.General.lastHTTPURLOpenedDate.reset()
+  }
+
+  func testUserRecentlyOpenedURL() {
+    let date = Date()
+    Preferences.General.lastHTTPURLOpenedDate.value = date
+    let isLikelyDefault = DefaultBrowserHelper.isBraveLikelyDefaultBrowser()
+    XCTAssertTrue(isLikelyDefault)
+  }
+
+  func testUserNeverOpenedURL() {
+    // User never opened a link
+    let isLikelyDefault = DefaultBrowserHelper.isBraveLikelyDefaultBrowser()
+    XCTAssertFalse(isLikelyDefault)
+  }
+
+  func testUserOpenedURL8DaysAgo() {
+    let date = Date()
+    Preferences.General.lastHTTPURLOpenedDate.value = date.addingTimeInterval(-8.days)
+    let isLikelyDefault = DefaultBrowserHelper.isBraveLikelyDefaultBrowser()
+    XCTAssertTrue(isLikelyDefault)
+  }
+
+  func testUserOpenedURL30DaysAgo() {
+    let date = Date()
+    Preferences.General.lastHTTPURLOpenedDate.value = date.addingTimeInterval(-30.days)
+    let isLikelyDefault = DefaultBrowserHelper.isBraveLikelyDefaultBrowser()
+    XCTAssertFalse(isLikelyDefault)
+  }
+}