Cellular capability detection

Kiwix-iOS/iOSExtensions.swift

@@ -60,3 +60,19 @@ extension Bundle {
         return (Bundle.main.object(forInfoDictionaryKey: kCFBundleVersionKey as String) as? String) ?? "Unknown"
     }
 }
+
+extension UIDevice {
+    class var hasCellularCapability: Bool {
+        // Get list of all interfaces on the local machine:
+        var ifaddr : UnsafeMutablePointer<ifaddrs>? = nil
+        if getifaddrs(&ifaddr) == 0 {
+            var ptr = ifaddr
+            while ptr != nil {
+                ptr = ptr!.pointee.ifa_next
+                let ifaName = String(utf8String: ptr!.pointee.ifa_name)
+                if ifaName == "pdp_ip0" {return true}
+            }
+        }
+        return false
+    }
+}

Kiwix/Kiwix-Bridging-Header.h

@@ -5,3 +5,4 @@
 #import "ZimReader.h"
 #import "ZimIndexer.h"
 
+#include <ifaddrs.h>

Kiwix/Operations/UIProcedure.swift

@@ -133,7 +133,7 @@ extension AlertProcedure {
             if book.state == .cloud {
                 alert.add(actionWithTitle: Localized.Library.download, style: .default) { _ in
                     OperationQueue.main.addOperation({
-                        if true {
+                        if UIDevice.hasCellularCapability {
                             UIQueue.shared.add(operation: download(context: context, bookID: book.id))
                         } else {
                             Network.shared.start(bookID: book.id, useWifiAndCellular: false)