Integrate UI with authentication flow.

blimp/client/core/android/java/src/org/chromium/blimp/core/settings/AboutBlimpPreferences.java

Index: blimp/client/core/android/java/src/org/chromium/blimp/core/settings/AboutBlimpPreferences.java
diff --git a/blimp/client/core/android/java/src/org/chromium/blimp/core/settings/AboutBlimpPreferences.java b/blimp/client/core/android/java/src/org/chromium/blimp/core/settings/AboutBlimpPreferences.java
index c03d0829f50d32d15bfe36edec2d2e18e3c75ae1..c840a451d1c9c350941ce4cd811b06a0ebda1aba 100644
--- a/blimp/client/core/android/java/src/org/chromium/blimp/core/settings/AboutBlimpPreferences.java
+++ b/blimp/client/core/android/java/src/org/chromium/blimp/core/settings/AboutBlimpPreferences.java
@@ -12,27 +12,32 @@ import android.preference.ListPreference;
 import android.preference.Preference;
 import android.preference.PreferenceFragment;
 import android.preference.PreferenceScreen;
+import android.preference.SwitchPreference;
 import android.support.v7.app.AlertDialog;
 
+import org.chromium.base.ContextUtils;
 import org.chromium.base.VisibleForTesting;
+import org.chromium.base.annotations.CalledByNative;
+import org.chromium.base.annotations.JNINamespace;
 import org.chromium.blimp.R;
-import org.chromium.blimp_public.BlimpSettingsCallbacks;
+import org.chromium.blimp.core.common.BlimpClientContextInternal;
+import org.chromium.blimp_public.BlimpClientContext;
+import org.chromium.components.sync.signin.ChromeSigninController;
 
 /**
- * Blimp preferences page in Chrome.
+ * Blimp preferences page in embedder.
  */
+@JNINamespace("blimp::client")
 public class AboutBlimpPreferences extends PreferenceFragment {
-
-    /**
-     * Blimp switch preference key, also the key for this PreferenceFragment.
-     */
-    public static final String PREF_BLIMP_SWITCH = "blimp_switch";
     /**
-     * Blimp assigner URL preference key.
+     * If this fragment is waiting for user sign in.
      */
-    public static final String PREF_ASSIGNER_URL = "blimp_assigner_url";
+    @VisibleForTesting
+    protected boolean mWaitForSignIn = false;
 
-    private static BlimpSettingsCallbacks sSettingsCallback;
+    private static BlimpClientContext sBlimpClientContext;
+
+    private long mNativeBlimpSettingsAndroid;
 
     /**
      * Attach the blimp setting preferences to a {@link PreferenceFragment}.
@@ -44,24 +49,43 @@ public class AboutBlimpPreferences extends PreferenceFragment {
         Preference blimpSetting = new Preference(fragment.getActivity());
         blimpSetting.setTitle(R.string.blimp_about_blimp_preferences);
         blimpSetting.setFragment(AboutBlimpPreferences.class.getName());
-        blimpSetting.setKey(AboutBlimpPreferences.PREF_BLIMP_SWITCH);
+        blimpSetting.setKey(PreferencesUtil.PREF_BLIMP_SWITCH);
 
         screen.addPreference(blimpSetting);
         fragment.setPreferenceScreen(screen);
     }
 
     /**
-     * Register Chrome callback related to Blimp settings.
-     * @param callback
+     * Register the {@link BlimpClientContext}.
      */
-    public static void registerCallback(BlimpSettingsCallbacks callback) {
-        sSettingsCallback = callback;
+    public static void setContext(BlimpClientContext blimpContext) {
+        sBlimpClientContext = blimpContext;
     }
 
     @Override
     public void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
+        initNativeLayer();
         getActivity().setTitle(R.string.blimp_about_blimp_preferences);
+        updateSettingPage();
+    }
+
+    @Override
+    public void onResume() {
+        super.onResume();
+        updateSettingPage();
+    }
+
+    @Override
+    public void onDestroy() {
+        super.onDestroy();
+        destroyNativeLayer();
+    }
+
+    // Reload the items in preferences list.
+    private void updateSettingPage() {
+        PreferenceScreen screen = getPreferenceScreen();
+        if (screen != null) screen.removeAll();
         addPreferencesFromResource(R.xml.blimp_preferences);
 
         setupBlimpSwitch();
@@ -69,26 +93,66 @@ public class AboutBlimpPreferences extends PreferenceFragment {
     }
 
     /**
-     * Setup the switch preference for blimp.
+     * Setup the switch preference for Blimp.
      */
     private void setupBlimpSwitch() {
         // TODO(xingliu): Use {@link ChromeSwitchPreference} after move this class to Chrome.
         // http://crbug.com/630675
-        final Preference pref = findPreference(PREF_BLIMP_SWITCH);
+        final SwitchPreference pref =
+                (SwitchPreference) findPreference(PreferencesUtil.PREF_BLIMP_SWITCH);
+
+        if (!isSignedIn()) pref.setChecked(false);
 
         pref.setOnPreferenceChangeListener(new Preference.OnPreferenceChangeListener() {
             @Override
             public boolean onPreferenceChange(Preference preference, Object newValue) {
-                // For blimp client 0.6, if blimp switch changed, show restart dialog.
-                // TODO(xingliu): Figure out if we need to close all tabs before restart or reset
-                // the settings before restarting.
-                showRestartDialog(getActivity(), R.string.blimp_switch_changed_please_restart);
-                return true;
+                return onBlimpSwitchPreferenceChange((boolean) newValue);
             }
         });
     }
 
     /**
+      * Handles switch preference change.
+      * @param switchValue The new value of the preference.
+      * @return If the new value will be persisted.
+      */
+    private boolean onBlimpSwitchPreferenceChange(boolean switchValue) {
+        if (switchValue) {
+            if (isSignedIn()) {
+                // If user has signed in and the switch is turned on, start authentication.
+                sBlimpClientContext.connect();
+            } else {
+                // If user didn't sign in, show a dialog to let the user sign in.
+                showPleaseSignInDialog();
+                return false;
+            }
+        }
+        return true;
+    }
+
+    /**
+     * Show please sign in dialog, it will show AccountSigninView to let user to sign in.

[David Trainor- moved to gerrit, 2016/08/29 05:12:24]

Probably don't need "please" in this flow :).

[xingliu, 2016/08/30 04:47:42]

Done.

+     *
+     * If the user signed in after clicking the confirm button, turn on the Blimp switch and connect
+     * to the engine.
+     */
+    private void showPleaseSignInDialog() {
+        final Context context = getActivity();
+        new AlertDialog.Builder(context)
+                .setTitle(R.string.blimp_sign_in_title)
+                .setMessage(R.string.blimp_sign_in_msg)
+                .setPositiveButton(R.string.blimp_sign_in_btn,
+                        new DialogInterface.OnClickListener() {
+                            @Override
+                            public void onClick(DialogInterface dialog, int which) {
+                                startUserSignInFlow();
+                            }
+                        })
+                .create()
+                .show();
+    }
+
+    /**
      * When the user taps on the current assigner, a list of available assigners pops up.
      * User is allowed to change the assigner which is saved to shared preferences.
      * A dialog is displayed which prompts the user to restart the application.
@@ -98,7 +162,13 @@ public class AboutBlimpPreferences extends PreferenceFragment {
     private void setupAssignerPreferences() {
         final Activity activity = getActivity();
 
-        final ListPreference listPreference = (ListPreference) findPreference(PREF_ASSIGNER_URL);
+        final ListPreference listPreference =
+                (ListPreference) findPreference(PreferencesUtil.PREF_ASSIGNER_URL);
+
+        // Set to default assigner URL on first time loading this UI.
+        if (listPreference.getValue() == null) {
+            listPreference.setValue(PreferencesUtil.DEFAULT_ASSIGNER_URL);

[David Trainor- moved to gerrit, 2016/08/29 05:12:24]

Can we use getLastUsedAssigner()?

[xingliu, 2016/08/30 04:47:42]

Done. Make sense.

+        }
         listPreference.setSummary(listPreference.getValue());
 
         listPreference.setOnPreferenceChangeListener(new Preference.OnPreferenceChangeListener() {
@@ -117,7 +187,7 @@ public class AboutBlimpPreferences extends PreferenceFragment {
      * @param context The context where we display the restart browser dialog.
      * @param message The message shown to the user.
      */
-    private static void showRestartDialog(final Context context, int message) {
+    private void showRestartDialog(final Context context, int message) {
         new AlertDialog.Builder(context)
                 .setTitle(R.string.blimp_restart_blimp)
                 .setMessage(message)
@@ -136,9 +206,71 @@ public class AboutBlimpPreferences extends PreferenceFragment {
      * Restart the browser.
      */
     @VisibleForTesting
-    protected static void restartBrowser() {
-        if (sSettingsCallback != null) {
-            sSettingsCallback.onRestartBrowserRequested();
+    protected void restartBrowser() {
+        assert sBlimpClientContext != null;
+        BlimpClientContextInternal contextInternal =
+                (BlimpClientContextInternal) sBlimpClientContext;
+
+        contextInternal.getDelegate().restartBrowser();
+    }
+
+    /**
+     * Start user sign in flow to let the user pick an existing account or create new account.
+     */
+    private void startUserSignInFlow() {
+        mWaitForSignIn = true;
+        assert sBlimpClientContext != null;
+        BlimpClientContextInternal contextInternal =
+                (BlimpClientContextInternal) sBlimpClientContext;
+
+        contextInternal.getDelegate().startUserSignInFlow(getActivity());
+    }
+
+    private boolean isSignedIn() {
+        return ChromeSigninController.get(ContextUtils.getApplicationContext()).isSignedIn();
+    }
+
+    @VisibleForTesting
+    @CalledByNative
+    protected void onSignedOut() {
+        // If user signed out, turn off the switch. We also do a sign in state check on
+        // {@link AboutBlimpPreferences#updateSettingPage()}.
+        final SwitchPreference pref =
+                (SwitchPreference) findPreference(PreferencesUtil.PREF_BLIMP_SWITCH);
+        pref.setChecked(false);

[David Trainor- moved to gerrit, 2016/08/29 05:12:24]

If we were on should we alert the user and shut down blimp?

[xingliu, 2016/08/30 04:47:42]

This logic is mostly not get called since the UI is destroyed after come back
from sign out view.

Can I do it in separate CL? probably need to move this stuff into embedder
delegate. It seems to need an activity context with certain configuration in the
manifest.

[David Trainor- moved to gerrit, 2016/08/30 20:46:29]

Acknowledged.

+    }
+
+    @VisibleForTesting
+    @CalledByNative
+    protected void onSignedIn() {
+        // If user came back from sign in flow, turn on the switch and connect to engine.
+        // This logic won't trigger the {@link OnPreferenceChangeListener} call.
+        if (mWaitForSignIn) {
+            final SwitchPreference pref =
+                    (SwitchPreference) findPreference(PreferencesUtil.PREF_BLIMP_SWITCH);
+            pref.setChecked(true);
+
+            sBlimpClientContext.connect();
+            mWaitForSignIn = false;
         }
     }
+
+    @VisibleForTesting
+    protected void initNativeLayer() {

[David Trainor- moved to gerrit, 2016/08/29 05:12:24]

Maybe call this initializeNative or just initialize()?

[xingliu, 2016/08/30 04:47:42]

Done.

+        mNativeBlimpSettingsAndroid = nativeInit();
+        assert sBlimpClientContext != null && mNativeBlimpSettingsAndroid != 0;
+
+        // Set identity source pointer in native code.
+        BlimpClientContextInternal contextInternal =
+                (BlimpClientContextInternal) sBlimpClientContext;
+        contextInternal.initSettingsPage(mNativeBlimpSettingsAndroid);

[David Trainor- moved to gerrit, 2016/08/29 05:12:24]

Just pass this class in and allow the native side to pull the pointer from the
jobject.

In native you can have a BlimpSettingsAndroid::FromJavaObject() that can return
it.

[xingliu, 2016/08/30 04:47:42]

Done. Now, it's similar to other Jni bridges.

+    }
+
+    @VisibleForTesting
+    protected void destroyNativeLayer() {
+        nativeDestroy(mNativeBlimpSettingsAndroid);
+    }
+
+    private native long nativeInit();
+    private native void nativeDestroy(long nativeBlimpSettingsAndroid);
 }