#2348 updated formatIpForAndroidPie to use pattern matching and added unit tests

core/src/main/java/org/kiwix/kiwixmobile/core/utils/ServerUtils.kt

@@ -17,6 +17,8 @@
  */
 package org.kiwix.kiwixmobile.core.utils
 
+import android.util.Log
+import org.kiwix.kiwixmobile.core.main.AddNoteDialog.TAG
 import java.net.InetAddress
 import java.net.NetworkInterface
 import java.net.SocketException
@@ -37,9 +39,12 @@ object ServerUtils {
       }
       // To remove extra characters from IP for Android Pie
       ip = formatIpForAndroidPie(ip)
-    } catch (e: SocketException) {
-      e.printStackTrace()
-      ip += "Something Wrong! $e\n"
+    } catch (socketException: SocketException) {
+      Log.e(TAG, "$socketException")
+      ip += "Something Wrong! $socketException\n"
+    } catch (invalidIpException: IllegalArgumentException) {
+      Log.e(TAG, "$invalidIpException")
+      ip += "Something Wrong! $invalidIpException\n"
     }
     return ip
   }
@@ -48,17 +53,13 @@ object ServerUtils {
     (inetAddress.hostAddress + "\n").takeIf { inetAddress.isSiteLocalAddress } ?: ""
 
   @Suppress("MagicNumber")
-  private fun formatIpForAndroidPie(ip: String): String {
-    var result: String = ip
-    if (ip.length > 14) {
-      for (i in 14 until ip.length) {
-        if (ip[i] == '.') {
-          result = ip.substring(0, i - 2)
-          break
-        }
-      }
-    }
-    return result
+  fun formatIpForAndroidPie(ip: String): String {
+    // regex from OneCricketeer @ https://stackoverflow.com/a/15875500/14053602
+    val ipRegex =
+      "(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)"
+        .toRegex()
+    val ipMatch = ipRegex.find(ip, 0) ?: throw IllegalArgumentException()
+    return ipMatch.value
   }
 
   @JvmStatic fun getSocketAddress(): String =

core/src/test/java/org/kiwix/kiwixmobile/core/utils/ServerUtilsTest.kt

@@ -0,0 +1,61 @@
+/*
+ * Kiwix Android
+ * Copyright (c) 2020 Kiwix <android.kiwix.org>
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+package org.kiwix.kiwixmobile.core.utils
+
+import org.assertj.core.api.Assertions.assertThat
+import org.junit.Test
+
+internal class ServerUtilsTest {
+
+  @Test
+  internal fun `formatIpForAndroidPie should return first ip occurrence of pie address`() {
+    assertThat(
+      ServerUtils.formatIpForAndroidPie(
+        """
+      fec0::15:b2ff:fe00:0
+      fec0::15d6:ece1:61fb:5b55
+      192.168.232.2
+      fec0::d8d1:9ff:fe42:160c
+      fec0::8d6e:2327:6d9f:ce75
+      192.168.200.2
+    """.trimIndent()
+      )
+    ).isEqualTo(
+      "192.168.232.2"
+    )
+  }
+
+  @Test
+  internal fun `formatIpForAndroidPie should return full ip on given ip`() {
+    assertThat(
+      ServerUtils.formatIpForAndroidPie(
+        """
+      192.168.232.2
+    """.trimIndent()
+      )
+    ).isEqualTo(
+      "192.168.232.2"
+    )
+  }
+
+  @Test(expected = IllegalArgumentException::class)
+  internal fun `formatIpForAndroidPie should throw invalid argument exception on invalid ip`() {
+    ServerUtils.formatIpForAndroidPie("invalid ip")
+  }
+}