Revert "Revert "CTS for timestamp in ScanResult""

With b/6979211 fixed, we can reinstate timestamps.

This reverts commit a21bd2a58a73b0aac2700a551e82824c7a44f42a

Change-Id: I1066567c728b233ad1d6c6af912c32ef099580e6
diff --git a/tests/tests/net/src/android/net/wifi/cts/ScanResultTest.java b/tests/tests/net/src/android/net/wifi/cts/ScanResultTest.java
index 26cfff83..c9b82ee 100644
--- a/tests/tests/net/src/android/net/wifi/cts/ScanResultTest.java
+++ b/tests/tests/net/src/android/net/wifi/cts/ScanResultTest.java
@@ -26,6 +26,7 @@
 import android.net.wifi.WifiManager;
 import android.net.wifi.WifiManager.WifiLock;
 import android.test.AndroidTestCase;
+import android.util.Log;
 
 public class ScanResultTest extends AndroidTestCase {
     private static class MySync {
@@ -39,11 +40,14 @@
     private static final int STATE_NULL = 0;
     private static final int STATE_WIFI_CHANGING = 1;
     private static final int STATE_WIFI_CHANGED = 2;
+    private static final int STATE_START_SCAN = 3;
+    private static final int STATE_SCAN_RESULTS_AVAILABLE = 4;
 
     private static final String TAG = "WifiInfoTest";
     private static final int TIMEOUT_MSEC = 6000;
     private static final int WAIT_MSEC = 60;
-    private static final int DURATION = 10000;
+    private static final int ENABLE_WAIT_MSEC = 10000;
+    private static final int SCAN_WAIT_MSEC = 10000;
     private IntentFilter mIntentFilter;
     private final BroadcastReceiver mReceiver = new BroadcastReceiver() {
         @Override
@@ -54,6 +58,11 @@
                     mMySync.expectedState = STATE_WIFI_CHANGED;
                     mMySync.notify();
                 }
+            } else if (action.equals(WifiManager.SCAN_RESULTS_AVAILABLE_ACTION)) {
+                synchronized (mMySync) {
+                    mMySync.expectedState = STATE_SCAN_RESULTS_AVAILABLE;
+                    mMySync.notify();
+                }
             }
         }
     };
@@ -83,7 +92,7 @@
         mWifiLock.acquire();
         if (!mWifiManager.isWifiEnabled())
             setWifiEnabled(true);
-        Thread.sleep(DURATION);
+        Thread.sleep(ENABLE_WAIT_MSEC);
         assertTrue(mWifiManager.isWifiEnabled());
         mMySync.expectedState = STATE_NULL;
     }
@@ -99,7 +108,7 @@
         mContext.unregisterReceiver(mReceiver);
         if (!mWifiManager.isWifiEnabled())
             setWifiEnabled(true);
-        Thread.sleep(DURATION);
+        Thread.sleep(ENABLE_WAIT_MSEC);
         super.tearDown();
     }
 
@@ -107,11 +116,15 @@
         synchronized (mMySync) {
             mMySync.expectedState = STATE_WIFI_CHANGING;
             assertTrue(mWifiManager.setWifiEnabled(enable));
-            long timeout = System.currentTimeMillis() + TIMEOUT_MSEC;
-            while (System.currentTimeMillis() < timeout
-                    && mMySync.expectedState == STATE_WIFI_CHANGING)
-                mMySync.wait(WAIT_MSEC);
-        }
+            waitForBroadcast(TIMEOUT_MSEC, STATE_WIFI_CHANGED);
+       }
+    }
+
+    private void waitForBroadcast(long timeout, int expectedState) throws Exception {
+        long waitTime = System.currentTimeMillis() + timeout;
+        while (System.currentTimeMillis() < waitTime
+                && mMySync.expectedState != expectedState)
+            mMySync.wait(WAIT_MSEC);
     }
 
     public void testScanResultProperties() {
@@ -127,4 +140,49 @@
         }
     }
 
+    private void scanAndWait() throws Exception {
+        synchronized (mMySync) {
+            mMySync.expectedState = STATE_START_SCAN;
+            mWifiManager.startScan();
+            waitForBroadcast(SCAN_WAIT_MSEC, STATE_SCAN_RESULTS_AVAILABLE);
+        }
+   }
+
+    public void testScanResultTimeStamp() throws Exception {
+        if (!WifiFeature.isWifiSupported(getContext())) {
+            // skip the test if WiFi is not supported
+            return;
+        }
+
+        long timestamp = 0;
+        String BSSID = null;
+
+        /* Multiple scans to ensure bssid is updated */
+        scanAndWait();
+        scanAndWait();
+        scanAndWait();
+
+        List<ScanResult> scanResults = mWifiManager.getScanResults();
+        for (ScanResult result : scanResults) {
+            BSSID = result.BSSID;
+            timestamp = result.timestamp;
+            assertTrue(timestamp != 0);
+            break;
+        }
+
+        scanAndWait();
+        scanAndWait();
+        scanAndWait();
+
+        scanResults = mWifiManager.getScanResults();
+        for (ScanResult result : scanResults) {
+            if (result.BSSID.equals(BSSID)) {
+                long timeDiff = (result.timestamp - timestamp) / 1000;
+                assertTrue (timeDiff > 0);
+                assertTrue (timeDiff < 6 * SCAN_WAIT_MSEC);
+            }
+        }
+
+    }
+
 }