ui: display latest handshake time

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

ui/src/main/java/com/wireguard/android/fragment/TunnelDetailFragment.kt

@@ -112,16 +112,25 @@ class TunnelDetailFragment : BaseFragment(), MenuProvider {
                 val peer: TunnelDetailPeerBinding = DataBindingUtil.getBinding(binding.peersLayout.getChildAt(i))
                         ?: continue
                 val publicKey = peer.item!!.publicKey
-                val rx = statistics.peerRx(publicKey)
+                val peerStats = statistics.peer(publicKey)
-                val tx = statistics.peerTx(publicKey)
+                if (peerStats == null || (peerStats.rxBytes == 0L && peerStats.txBytes == 0L)) {
-                if (rx == 0L && tx == 0L) {
                     peer.transferLabel.visibility = View.GONE
                     peer.transferText.visibility = View.GONE
-                    continue
+                } else {
+                    peer.transferText.text = getString(R.string.transfer_rx_tx,
+                        QuantityFormatter.formatBytes(peerStats.rxBytes),
+                        QuantityFormatter.formatBytes(peerStats.txBytes))
+                    peer.transferLabel.visibility = View.VISIBLE
+                    peer.transferText.visibility = View.VISIBLE
+                }
+                if (peerStats == null || peerStats.latestHandshakeEpochMillis == 0L) {
+                    peer.latestHandshakeLabel.visibility = View.GONE
+                    peer.latestHandshakeText.visibility = View.GONE
+                } else {
+                    peer.latestHandshakeText.text = QuantityFormatter.formatEpochAgo(peerStats.latestHandshakeEpochMillis)
+                    peer.latestHandshakeLabel.visibility = View.VISIBLE
+                    peer.latestHandshakeText.visibility = View.VISIBLE
                 }
-                peer.transferText.text = getString(R.string.transfer_rx_tx, QuantityFormatter.formatBytes(rx), QuantityFormatter.formatBytes(tx))
-                peer.transferLabel.visibility = View.VISIBLE
-                peer.transferText.visibility = View.VISIBLE
             }
         } catch (e: Throwable) {
             for (i in 0 until binding.peersLayout.childCount) {
@@ -129,6 +138,8 @@ class TunnelDetailFragment : BaseFragment(), MenuProvider {
                         ?: continue
                 peer.transferLabel.visibility = View.GONE
                 peer.transferText.visibility = View.GONE
+                peer.latestHandshakeLabel.visibility = View.GONE
+                peer.latestHandshakeText.visibility = View.GONE
             }
         }
     }

ui/src/main/java/com/wireguard/android/util/QuantityFormatter.kt

@@ -5,8 +5,17 @@
 
 package com.wireguard.android.util
 
+import android.icu.text.ListFormatter
+import android.icu.text.MeasureFormat
+import android.icu.text.RelativeDateTimeFormatter
+import android.icu.util.Measure
+import android.icu.util.MeasureUnit
+import android.os.Build
 import com.wireguard.android.Application
 import com.wireguard.android.R
+import java.util.Locale
+import kotlin.time.DurationUnit
+import kotlin.time.toDuration
 
 object QuantityFormatter {
     fun formatBytes(bytes: Long): String {
@@ -19,4 +28,40 @@ object QuantityFormatter {
             else -> context.getString(R.string.transfer_tibibytes, bytes / (1024.0 * 1024.0 * 1024.0) / 1024.0)
         }
     }
+
+    fun formatEpochAgo(epochMillis: Long): String {
+        var span = (System.currentTimeMillis() - epochMillis) / 1000
+
+        if (Build.VERSION.SDK_INT < Build.VERSION_CODES.N)
+            return Application.get().applicationContext.getString(R.string.latest_handshake_ago, span.toDuration(DurationUnit.SECONDS).toString())
+
+        if (span <= 0L)
+            return RelativeDateTimeFormatter.getInstance().format(RelativeDateTimeFormatter.Direction.PLAIN, RelativeDateTimeFormatter.AbsoluteUnit.NOW)
+        val measureFormat = MeasureFormat.getInstance(Locale.getDefault(), MeasureFormat.FormatWidth.WIDE)
+        val parts = ArrayList<CharSequence>(4)
+        if (span >= 24 * 60 * 60L) {
+            val v = span / (24 * 60 * 60L)
+            parts.add(measureFormat.format(Measure(v, MeasureUnit.DAY)))
+            span -= v * (24 * 60 * 60L)
+        }
+        if (span >= 60 * 60L) {
+            val v = span / (60 * 60L)
+            parts.add(measureFormat.format(Measure(v, MeasureUnit.HOUR)))
+            span -= v * (60 * 60L)
+        }
+        if (span >= 60L) {
+            val v = span / 60L
+            parts.add(measureFormat.format(Measure(v, MeasureUnit.MINUTE)))
+            span -= v * 60L
+        }
+        if (span > 0L)
+            parts.add(measureFormat.format(Measure(span, MeasureUnit.SECOND)))
+
+        val joined = if (Build.VERSION.SDK_INT < Build.VERSION_CODES.TIRAMISU)
+            parts.joinToString()
+        else
+            ListFormatter.getInstance(Locale.getDefault(), ListFormatter.Type.UNITS, ListFormatter.Width.SHORT).format(parts)
+
+        return Application.get().applicationContext.getString(R.string.latest_handshake_ago, joined)
+    }
 }

ui/src/main/res/layout/tunnel_detail_peer.xml

@@ -171,7 +171,7 @@
                 android:id="@+id/transfer_label"
                 android:layout_width="wrap_content"
                 android:layout_height="wrap_content"
-                android:layout_below="@+id/endpoint_text"
+                android:layout_below="@+id/persistent_keepalive_text"
                 android:layout_marginTop="8dp"
                 android:labelFor="@+id/transfer_text"
                 android:text="@string/transfer"
@@ -194,6 +194,34 @@
                 app:layout_constraintTop_toBottomOf="@+id/transfer_label"
                 tools:text="1024 MB"
                 tools:visibility="visible" />
+
+            <TextView
+                android:id="@+id/latest_handshake_label"
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:layout_below="@+id/transfer_text"
+                android:layout_marginTop="8dp"
+                android:labelFor="@+id/latest_handshake_text"
+                android:text="@string/latest_handshake"
+                android:visibility="gone"
+                app:layout_constraintStart_toStartOf="parent"
+                app:layout_constraintTop_toBottomOf="@+id/transfer_text"
+                tools:visibility="visible" />
+
+            <TextView
+                android:id="@+id/latest_handshake_text"
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:layout_below="@+id/latest_handshake_label"
+                android:contentDescription="@string/latest_handshake"
+                android:nextFocusUp="@id/transfer_text"
+                android:onClick="@{ClipboardUtils::copyTextView}"
+                android:textAppearance="?attr/textAppearanceBodyLarge"
+                android:visibility="gone"
+                app:layout_constraintStart_toStartOf="parent"
+                app:layout_constraintTop_toBottomOf="@+id/latest_handshake_label"
+                tools:text="4 minutes, 27 seconds ago"
+                tools:visibility="visible" />
         </androidx.constraintlayout.widget.ConstraintLayout>
     </com.google.android.material.card.MaterialCardView>
 </layout>

ui/src/main/res/values/strings.xml

@@ -140,6 +140,8 @@
     <string name="key_length_explanation_base64">: WireGuard base64 keys must be 44 characters (32 bytes)</string>
     <string name="key_length_explanation_binary">: WireGuard keys must be 32 bytes</string>
     <string name="key_length_explanation_hex">: WireGuard hex keys must be 64 characters (32 bytes)</string>
+    <string name="latest_handshake">Latest handshake</string>
+    <string name="latest_handshake_ago">%s ago</string>
     <string name="listen_port">Listen port</string>
     <string name="log_export_error">Unable to export log: %s</string>
     <string name="log_export_subject">WireGuard Android Log File</string>