Dactyloidae iOS initial commit

mobile/ios/Shared/UserAgent.swift

@@ -0,0 +1,131 @@
+/* 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 http://mozilla.org/MPL/2.0/. */
+
+import AVFoundation
+import UIKit
+
+open class UserAgent {
+    private static var defaults = UserDefaults(suiteName: AppInfo.sharedContainerIdentifier)!
+
+    private static func clientUserAgent(prefix: String) -> String {
+        return "\(prefix)/\(AppInfo.appVersion)b\(AppInfo.buildNumber) (\(DeviceInfo.deviceModel()); iPhone OS \(UIDevice.current.systemVersion)) (\(AppInfo.displayName))"
+    }
+
+    open static var syncUserAgent: String {
+        return clientUserAgent(prefix: "Firefox-iOS-Sync")
+    }
+
+    open static var tokenServerClientUserAgent: String {
+        return clientUserAgent(prefix: "Firefox-iOS-Token")
+    }
+
+    open static var fxaUserAgent: String {
+        return clientUserAgent(prefix: "Firefox-iOS-FxA")
+    }
+
+    open static var defaultClientUserAgent: String {
+        return clientUserAgent(prefix: "Firefox-iOS")
+    }
+
+    /**
+     * Use this if you know that a value must have been computed before your
+     * code runs, or you don't mind failure.
+     */
+    open static func cachedUserAgent(checkiOSVersion: Bool = true,
+                                     checkFirefoxVersion: Bool = true,
+                                     checkFirefoxBuildNumber: Bool = true) -> String? {
+        let currentiOSVersion = UIDevice.current.systemVersion
+        let lastiOSVersion = defaults.string(forKey: "LastDeviceSystemVersionNumber")
+
+        let currentFirefoxBuildNumber = AppInfo.buildNumber
+        let currentFirefoxVersion = AppInfo.appVersion
+        let lastFirefoxVersion = defaults.string(forKey: "LastFirefoxVersionNumber")
+        let lastFirefoxBuildNumber = defaults.string(forKey: "LastFirefoxBuildNumber")
+        
+        if let firefoxUA = defaults.string(forKey: "UserAgent") {
+            if (!checkiOSVersion || (lastiOSVersion == currentiOSVersion))
+                && (!checkFirefoxVersion || (lastFirefoxVersion == currentFirefoxVersion)
+                && (!checkFirefoxBuildNumber || (lastFirefoxBuildNumber == currentFirefoxBuildNumber))) {
+                return firefoxUA
+            }
+        }
+
+        return nil
+    }
+
+    /**
+     * This will typically return quickly, but can require creation of a UIWebView.
+     * As a result, it must be called on the UI thread.
+     */
+    open static func defaultUserAgent() -> String {
+        assert(Thread.current.isMainThread, "This method must be called on the main thread.")
+
+        if let firefoxUA = UserAgent.cachedUserAgent(checkiOSVersion: true) {
+            return firefoxUA
+        }
+
+        let webView = UIWebView()
+
+        let appVersion = AppInfo.appVersion
+        let buildNumber = AppInfo.buildNumber
+        let currentiOSVersion = UIDevice.current.systemVersion
+        defaults.set(currentiOSVersion, forKey: "LastDeviceSystemVersionNumber")
+        defaults.set(appVersion, forKey: "LastFirefoxVersionNumber")
+        defaults.set(buildNumber, forKey: "LastFirefoxBuildNumber")
+
+        let userAgent = webView.stringByEvaluatingJavaScript(from: "navigator.userAgent")!
+
+        // Extract the WebKit version and use it as the Safari version.
+        let webKitVersionRegex = try! NSRegularExpression(pattern: "AppleWebKit/([^ ]+) ", options: [])
+
+        let match = webKitVersionRegex.firstMatch(in: userAgent, options: [],
+            range: NSRange(location: 0, length: userAgent.characters.count))
+
+        if match == nil {
+            print("Error: Unable to determine WebKit version in UA.")
+            return userAgent     // Fall back to Safari's.
+        }
+
+        let webKitVersion = (userAgent as NSString).substring(with: match!.rangeAt(1))
+
+        // Insert "FxiOS/<version>" before the Mobile/ section.
+        let mobileRange = (userAgent as NSString).range(of: "Mobile/")
+        if mobileRange.location == NSNotFound {
+            print("Error: Unable to find Mobile section in UA.")
+            return userAgent     // Fall back to Safari's.
+        }
+
+        let mutableUA = NSMutableString(string: userAgent)
+        mutableUA.insert("FxiOS/\(appVersion)b\(AppInfo.buildNumber) ", at: mobileRange.location)
+
+        let firefoxUA = "\(mutableUA) Safari/\(webKitVersion)"
+
+        defaults.set(firefoxUA, forKey: "UserAgent")
+
+        return firefoxUA
+    }
+
+    open static func desktopUserAgent() -> String {
+        let userAgent = NSMutableString(string: defaultUserAgent())
+
+        // Spoof platform section
+        let platformRegex = try! NSRegularExpression(pattern: "\\([^\\)]+\\)", options: [])
+        guard let platformMatch = platformRegex.firstMatch(in: userAgent as String, options: [], range: NSRange(location: 0, length: userAgent.length)) else {
+            print("Error: Unable to determine platform in UA.")
+            return String(userAgent)
+        }
+        userAgent.replaceCharacters(in: platformMatch.range, with: "(Macintosh; Intel Mac OS X 10_11_1)")
+
+        // Strip mobile section
+        let mobileRegex = try! NSRegularExpression(pattern: " FxiOS/[^ ]+ Mobile/[^ ]+", options: [])
+        
+        guard let mobileMatch = mobileRegex.firstMatch(in: userAgent as String, options: [], range: NSRange(location: 0, length: userAgent.length)) else {
+            print("Error: Unable to find Mobile section in UA.")
+            return String(userAgent)
+        }
+        userAgent.replaceCharacters(in: mobileMatch.range, with: "")
+
+        return String(userAgent)
+    }
+}