/*
 * Copyright (C) 2010 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.android.settings.wifi;

import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.content.pm.ActivityInfo;
import android.net.NetworkInfo.DetailedState;
import android.net.wifi.WifiConfiguration;
import android.net.wifi.WifiManager;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.preference.PreferenceScreen;
import android.text.TextUtils;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup;
import android.view.Window;
import android.view.inputmethod.InputMethodManager;
import android.widget.Button;
import android.widget.ProgressBar;
import android.widget.TextView;

import com.android.internal.util.AsyncChannel;
import com.android.settings.R;

import java.util.Collection;
import java.util.EnumMap;
import java.util.List;

/**
 * WifiSetings Activity specific for SetupWizard with X-Large screen size.
 */
public class WifiSettingsForSetupWizardXL extends Activity implements OnClickListener {
    private static final String TAG = "SetupWizard";
    private static final boolean DEBUG = true;

    // lock orientation into landscape or portrait
    private static final String EXTRA_PREFS_LANDSCAPE_LOCK = "extra_prefs_landscape_lock";
    private static final String EXTRA_PREFS_PORTRAIT_LOCK = "extra_prefs_portrait_lock";

    private static final EnumMap<DetailedState, DetailedState> sNetworkStateMap =
            new EnumMap<DetailedState, DetailedState>(DetailedState.class);

    static {
        sNetworkStateMap.put(DetailedState.IDLE, DetailedState.DISCONNECTED);
        sNetworkStateMap.put(DetailedState.SCANNING, DetailedState.SCANNING);
        sNetworkStateMap.put(DetailedState.CONNECTING, DetailedState.CONNECTING);
        sNetworkStateMap.put(DetailedState.AUTHENTICATING, DetailedState.CONNECTING);
        sNetworkStateMap.put(DetailedState.OBTAINING_IPADDR, DetailedState.CONNECTING);
        sNetworkStateMap.put(DetailedState.CONNECTED, DetailedState.CONNECTED);
        sNetworkStateMap.put(DetailedState.SUSPENDED, DetailedState.SUSPENDED);  // ?
        sNetworkStateMap.put(DetailedState.DISCONNECTING, DetailedState.DISCONNECTED);
        sNetworkStateMap.put(DetailedState.DISCONNECTED, DetailedState.DISCONNECTED);
        sNetworkStateMap.put(DetailedState.FAILED, DetailedState.FAILED);
    }

    private WifiSettings mWifiSettings;
    private WifiManager mWifiManager;
    private WifiManager.Channel mChannel;

    /** Used for resizing a padding above title. Hiden when software keyboard is shown. */
    private View mTopPadding;

    /** Used for resizing a padding of main content. Hiden when software keyboard is shown. */
    private View mContentPadding;

    private TextView mTitleView;
    /**
     * The name of a network currently connecting, or trying to connect.
     * This may be empty ("") at first, and updated when configuration is changed.
     */
    private CharSequence mNetworkName = "";
    private CharSequence mEditingTitle;

    private ProgressBar mProgressBar;
    private View mTopDividerNoProgress;
    /**
     * Used for resizing a padding between WifiSettings preference and bottom bar when
     * ProgressBar is visible as a top divider.
     */
    private View mBottomPadding;

    private Button mAddNetworkButton;
    private Button mRefreshButton;
    private Button mSkipOrNextButton;
    private Button mBackButton;

    private Button mConnectButton;

    /**
     * View enclosing {@link WifiSettings}.
     */
    private View mWifiSettingsFragmentLayout;
    private View mConnectingStatusLayout;
    private TextView mConnectingStatusView;

    /*
     * States of current screen, which should be saved and restored when Activity is relaunched
     * with orientation change, etc.
     */
    private static final int SCREEN_STATE_DISCONNECTED = 0;
    private static final int SCREEN_STATE_EDITING = 1;
    private static final int SCREEN_STATE_CONNECTING = 2;
    private static final int SCREEN_STATE_CONNECTED = 3;

    /** Current screen state. */
    private int mScreenState = SCREEN_STATE_DISCONNECTED;

    private WifiConfigUiForSetupWizardXL mWifiConfig;

    private InputMethodManager mInputMethodManager;

    /**
     * Previous network connection state reported by main Wifi module.
     *
     * Note that we don't use original {@link DetailedState} object but simplified one translated
     * using sNetworkStateMap.
     */
    private DetailedState mPreviousNetworkState = DetailedState.DISCONNECTED;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        requestWindowFeature(Window.FEATURE_NO_TITLE);
        setContentView(R.layout.wifi_settings_for_setup_wizard_xl);

        mWifiManager = (WifiManager)getSystemService(Context.WIFI_SERVICE);
        mChannel = mWifiManager.initialize(this, getMainLooper(), null);
        // There's no button here enabling wifi network, so we need to enable it without
        // users' request.
        mWifiManager.setWifiEnabled(true);

        mWifiSettings =
                (WifiSettings)getFragmentManager().findFragmentById(R.id.wifi_setup_fragment);
        mInputMethodManager = (InputMethodManager)getSystemService(Context.INPUT_METHOD_SERVICE);

        initViews();

        // At first, Wifi module doesn't return SCANNING state (it's too early), so we manually
        // show it.
        showScanningState();
    }

    private void initViews() {
        Intent intent = getIntent();

        if (intent.getBooleanExtra("firstRun", false)) {
            final View layoutRoot = findViewById(R.id.layout_root);
            layoutRoot.setSystemUiVisibility(View.STATUS_BAR_DISABLE_BACK);
        }
        if (intent.getBooleanExtra(EXTRA_PREFS_LANDSCAPE_LOCK, false)) {
            setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_SENSOR_LANDSCAPE);
        }
        if (intent.getBooleanExtra(EXTRA_PREFS_PORTRAIT_LOCK, false)) {
            setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_SENSOR_PORTRAIT);
        }

        mTitleView = (TextView)findViewById(R.id.wifi_setup_title);
        mProgressBar = (ProgressBar)findViewById(R.id.scanning_progress_bar);
        mProgressBar.setMax(2);
        mTopDividerNoProgress = findViewById(R.id.top_divider_no_progress);
        mBottomPadding = findViewById(R.id.bottom_padding);

        mProgressBar.setVisibility(View.VISIBLE);
        mProgressBar.setIndeterminate(true);
        mTopDividerNoProgress.setVisibility(View.GONE);

        mAddNetworkButton = (Button)findViewById(R.id.wifi_setup_add_network);
        mAddNetworkButton.setOnClickListener(this);
        mRefreshButton = (Button)findViewById(R.id.wifi_setup_refresh_list);
        mRefreshButton.setOnClickListener(this);
        mSkipOrNextButton = (Button)findViewById(R.id.wifi_setup_skip_or_next);
        mSkipOrNextButton.setOnClickListener(this);
        mConnectButton = (Button)findViewById(R.id.wifi_setup_connect);
        mConnectButton.setOnClickListener(this);
        mBackButton = (Button)findViewById(R.id.wifi_setup_cancel);
        mBackButton.setOnClickListener(this);

        mTopPadding = findViewById(R.id.top_padding);
        mContentPadding = findViewById(R.id.content_padding);

        mWifiSettingsFragmentLayout = findViewById(R.id.wifi_settings_fragment_layout);
        mConnectingStatusLayout = findViewById(R.id.connecting_status_layout);
        mConnectingStatusView = (TextView) findViewById(R.id.connecting_status);
    }

    private void restoreFirstVisibilityState() {
        showDefaultTitle();
        mAddNetworkButton.setVisibility(View.VISIBLE);
        mRefreshButton.setVisibility(View.VISIBLE);
        mSkipOrNextButton.setVisibility(View.VISIBLE);
        mConnectButton.setVisibility(View.GONE);
        mBackButton.setVisibility(View.GONE);
        setPaddingVisibility(View.VISIBLE);
    }

    @Override
    public void onClick(View view) {
        hideSoftwareKeyboard();
        if (view == mAddNetworkButton) {
            if (DEBUG) Log.d(TAG, "AddNetwork button pressed");
            onAddNetworkButtonPressed();
        } else if (view == mRefreshButton) {
            if (DEBUG) Log.d(TAG, "Refresh button pressed");
            refreshAccessPoints(true);
        } else if (view == mSkipOrNextButton) {
            if (DEBUG) Log.d(TAG, "Skip/Next button pressed");
            if (TextUtils.equals(getString(R.string.wifi_setup_skip), ((Button)view).getText())) {
                // We don't want to let Wifi enabled when a user press skip without choosing
                // any access point.
                mWifiManager.setWifiEnabled(false);
                // Notify "skip"
                setResult(RESULT_FIRST_USER);
            } else {
                setResult(RESULT_OK);
            }
            finish();
        } else if (view == mConnectButton) {
            if (DEBUG) Log.d(TAG, "Connect button pressed");
            onConnectButtonPressed();
        } else if (view == mBackButton) {
            if (DEBUG) Log.d(TAG, "Back button pressed");
            onBackButtonPressed();
        }
    }

    private void hideSoftwareKeyboard() {
        if (DEBUG) Log.i(TAG, "Hiding software keyboard.");
        final View focusedView = getCurrentFocus();
        if (focusedView != null) {
            mInputMethodManager.hideSoftInputFromWindow(focusedView.getWindowToken(), 0);
        }
    }

    // Called from WifiSettings
    /* package */ void updateConnectionState(DetailedState originalState) {
        final DetailedState state = sNetworkStateMap.get(originalState);

        if (originalState == DetailedState.FAILED) {
            // We clean up the current connectivity status and let users select another network
            // if they want.
            refreshAccessPoints(true);
        }

        switch (state) {
        case SCANNING: {
            if (mScreenState == SCREEN_STATE_DISCONNECTED) {
                if (mWifiSettings.getAccessPointsCount() == 0) {
                    showScanningState();
                } else {
                    showDisconnectedProgressBar();
                    mWifiSettingsFragmentLayout.setVisibility(View.VISIBLE);
                    mBottomPadding.setVisibility(View.GONE);
                }
            } else {
                showDisconnectedProgressBar();
            }
            break;
        }
        case CONNECTING: {
            if (mScreenState == SCREEN_STATE_CONNECTING) {
                showConnectingState();
            }
            break;
        }
        case CONNECTED: {
            showConnectedState();
            break;
        }
        default:  // DISCONNECTED, FAILED
            if (mScreenState != SCREEN_STATE_CONNECTED &&
                    mWifiSettings.getAccessPointsCount() > 0) {
                showDisconnectedState(Summary.get(this, state));
            }
            break;
        }
        mPreviousNetworkState = state;
    }

    private void showDisconnectedState(String stateString) {
        showDisconnectedProgressBar();
        if (mScreenState == SCREEN_STATE_DISCONNECTED &&
                mWifiSettings.getAccessPointsCount() > 0) {
            mWifiSettingsFragmentLayout.setVisibility(View.VISIBLE);
            mBottomPadding.setVisibility(View.GONE);
        }
        mAddNetworkButton.setEnabled(true);
        mRefreshButton.setEnabled(true);
    }

    private void showConnectingState() {
        mScreenState = SCREEN_STATE_CONNECTING;

        mBackButton.setVisibility(View.VISIBLE);
        // We save this title and show it when authentication failed.
        mEditingTitle = mTitleView.getText();
        showConnectingTitle();
        showConnectingProgressBar();

        setPaddingVisibility(View.VISIBLE);
    }

    private void showConnectedState() {
        // Once we show "connected" screen, we won't change it even when the device becomes
        // disconnected afterwards. We keep the state unless a user explicitly cancel it
        // (by pressing "back" button).
        mScreenState = SCREEN_STATE_CONNECTED;

        hideSoftwareKeyboard();
        setPaddingVisibility(View.VISIBLE);

        showConnectedTitle();
        showConnectedProgressBar();

        mWifiSettingsFragmentLayout.setVisibility(View.GONE);
        mConnectingStatusLayout.setVisibility(View.VISIBLE);

        mConnectingStatusView.setText(R.string.wifi_setup_description_connected);
        mConnectButton.setVisibility(View.GONE);
        mAddNetworkButton.setVisibility(View.GONE);
        mRefreshButton.setVisibility(View.GONE);
        mBackButton.setVisibility(View.VISIBLE);
        mBackButton.setText(R.string.wifi_setup_back);
        mSkipOrNextButton.setVisibility(View.VISIBLE);
        mSkipOrNextButton.setEnabled(true);
    }

    private void showDefaultTitle() {
        mTitleView.setText(getString(R.string.wifi_setup_title));
    }

    private void showAddNetworkTitle() {
        mNetworkName = "";
        mTitleView.setText(R.string.wifi_setup_title_add_network);
    }

    private void showEditingTitle() {
        if (TextUtils.isEmpty(mNetworkName) && mWifiConfig != null) {
            if (mWifiConfig.getController() != null &&
                mWifiConfig.getController().getConfig() != null) {
                mNetworkName = mWifiConfig.getController().getConfig().SSID;
            } else {
                Log.w(TAG, "Unexpected null found (WifiController or WifiConfig is null). " +
                        "Ignore them.");
            }
        }
        mTitleView.setText(getString(R.string.wifi_setup_title_editing_network, mNetworkName));
    }

    private void showConnectingTitle() {
        if (TextUtils.isEmpty(mNetworkName) && mWifiConfig != null) {
            if (mWifiConfig.getController() != null &&
                    mWifiConfig.getController().getConfig() != null) {
                mNetworkName = mWifiConfig.getController().getConfig().SSID;
            } else {
                Log.w(TAG, "Unexpected null found (WifiController or WifiConfig is null). " +
                        "Ignore them.");
            }
        }
        mTitleView.setText(getString(R.string.wifi_setup_title_connecting_network, mNetworkName));
    }

    private void showConnectedTitle() {
        if (TextUtils.isEmpty(mNetworkName) && mWifiConfig != null) {
            if (mWifiConfig.getController() != null &&
                    mWifiConfig.getController().getConfig() != null) {
                mNetworkName = mWifiConfig.getController().getConfig().SSID;
            } else {
                Log.w(TAG, "Unexpected null found (WifiController or WifiConfig is null). " +
                        "Ignore them.");
            }
        }
        mTitleView.setText(getString(R.string.wifi_setup_title_connected_network, mNetworkName));
    }

    /**
     * Shows top divider with ProgressBar without defining the state of the ProgressBar.
     *
     * @see #showScanningProgressBar()
     * @see #showConnectedProgressBar()
     * @see #showConnectingProgressBar()
     */
    private void showTopDividerWithProgressBar() {
        mProgressBar.setVisibility(View.VISIBLE);
        mTopDividerNoProgress.setVisibility(View.GONE);
        mBottomPadding.setVisibility(View.GONE);
    }

    private void showScanningState() {
        setPaddingVisibility(View.VISIBLE);
        mWifiSettingsFragmentLayout.setVisibility(View.GONE);
        showScanningProgressBar();
    }

    private void onAddNetworkButtonPressed() {
        mWifiSettings.onAddNetworkPressed();
    }

    /**
     * Called when the screen enters wifi configuration UI. UI widget for configuring network
     * (a.k.a. ConfigPreference) should be taken care of by caller side.
     * This method should handle buttons' visibility/enabled.
     * @param selectedAccessPoint AccessPoint object being selected. null when a user pressed
     * "Add network" button, meaning there's no selected access point.
     */
    /* package */ void showConfigUi(AccessPoint selectedAccessPoint, boolean edit) {
        mScreenState = SCREEN_STATE_EDITING;

        if (selectedAccessPoint != null &&
                (selectedAccessPoint.security == AccessPoint.SECURITY_WEP ||
                        selectedAccessPoint.security == AccessPoint.SECURITY_PSK)) {
            // We forcibly set edit as true so that users can modify every field if they want,
            // while config UI doesn't allow them to edit some of them when edit is false
            // (e.g. password field is hiden when edit==false).
            edit = true;
        }

        // We don't want to keep scanning Wifi networks during users' configuring a network.
        mWifiSettings.pauseWifiScan();

        mWifiSettingsFragmentLayout.setVisibility(View.GONE);
        mConnectingStatusLayout.setVisibility(View.GONE);
        final ViewGroup parent = (ViewGroup)findViewById(R.id.wifi_config_ui);
        parent.setVisibility(View.VISIBLE);
        parent.removeAllViews();
        mWifiConfig = new WifiConfigUiForSetupWizardXL(this, parent, selectedAccessPoint, edit);

        if (selectedAccessPoint == null) {  // "Add network" flow
            showAddNetworkTitle();
            mConnectButton.setVisibility(View.VISIBLE);

            showDisconnectedProgressBar();
            showEditingButtonState();
        } else if (selectedAccessPoint.security == AccessPoint.SECURITY_NONE) {
            mNetworkName = selectedAccessPoint.getTitle().toString();

            // onConnectButtonPressed() will change visibility status.
            mConnectButton.performClick();
        } else {
            mNetworkName = selectedAccessPoint.getTitle().toString();
            showEditingTitle();
            showDisconnectedProgressBar();
            showEditingButtonState();
            if (selectedAccessPoint.security == AccessPoint.SECURITY_EAP) {
                onEapNetworkSelected();
            } else {
                mConnectButton.setVisibility(View.VISIBLE);

                // WifiConfigController shows Connect button as "Save" when edit==true and a user
                // tried to connect the network.
                // In SetupWizard, we just show the button as "Connect" instead.
                mConnectButton.setText(R.string.wifi_connect);
                mBackButton.setText(R.string.wifi_setup_cancel);
            }
        }
    }

    /**
     * Called before security fields are correctly set by {@link WifiConfigController}.
     *
     * @param view security field view
     * @param accessPointSecurity type of security. e.g. AccessPoint.SECURITY_NONE
     * @return true when it is ok for the caller to init security fields. false when
     * all security fields are managed by this method, and thus the caller shouldn't touch them.
     */
    /* package */ boolean initSecurityFields(View view, int accessPointSecurity) {
        // Reset all states tweaked below.
        view.findViewById(R.id.eap_not_supported).setVisibility(View.GONE);
        view.findViewById(R.id.eap_not_supported_for_add_network).setVisibility(View.GONE);
        view.findViewById(R.id.ssid_text).setVisibility(View.VISIBLE);
        view.findViewById(R.id.ssid_layout).setVisibility(View.VISIBLE);

        if (accessPointSecurity == AccessPoint.SECURITY_EAP) {
            setPaddingVisibility(View.VISIBLE);
            hideSoftwareKeyboard();

            // In SetupWizard for XLarge screen, we don't have enough space for showing
            // configurations needed for EAP. We instead disable the whole feature there and let
            // users configure those networks after the setup.
            if (view.findViewById(R.id.type_ssid).getVisibility() == View.VISIBLE) {
                view.findViewById(R.id.eap_not_supported_for_add_network)
                        .setVisibility(View.VISIBLE);
            } else {
                view.findViewById(R.id.eap_not_supported).setVisibility(View.VISIBLE);
            }
            view.findViewById(R.id.security_fields).setVisibility(View.GONE);
            view.findViewById(R.id.ssid_text).setVisibility(View.GONE);
            view.findViewById(R.id.ssid_layout).setVisibility(View.GONE);
            onEapNetworkSelected();

            // This method did init security fields by itself. The caller must not do it.
            return false;
        }

        mConnectButton.setVisibility(View.VISIBLE);
        setPaddingVisibility(View.GONE);

        // In "add network" flow, we'll see multiple initSecurityFields() calls with different
        // accessPointSecurity variable. We want to show software keyboard conditionally everytime
        // when this method is called.
        if (mWifiConfig != null) {
            if (accessPointSecurity == AccessPoint.SECURITY_PSK ||
                    accessPointSecurity == AccessPoint.SECURITY_WEP) {
                mWifiConfig.requestFocusAndShowKeyboard(R.id.password);
            } else {
                mWifiConfig.requestFocusAndShowKeyboard(R.id.ssid);
            }
        }

        // Let the caller init security fields.
        return true;
    }

    private void onEapNetworkSelected() {
        mConnectButton.setVisibility(View.GONE);
        mBackButton.setText(R.string.wifi_setup_back);
    }

    private void showEditingButtonState() {
        mSkipOrNextButton.setVisibility(View.GONE);
        mAddNetworkButton.setVisibility(View.GONE);
        mRefreshButton.setVisibility(View.GONE);
        mBackButton.setVisibility(View.VISIBLE);
    }

    // May be called when user press "connect" button in WifiDialog
    /* package */ void onConnectButtonPressed() {
        mScreenState = SCREEN_STATE_CONNECTING;

        mWifiSettings.submit(mWifiConfig.getController());

        // updateConnectionState() isn't called soon by the main Wifi module after the user's
        // "connect" request, and the user still sees "not connected" message for a while, which
        // looks strange for users though legitimate from the view of the module.
        //
        // We instead manually show "connecting" message before the system gets actual
        // "connecting" message from Wifi module.
        showConnectingState();

        // Might be better to delay showing this button.
        mBackButton.setVisibility(View.VISIBLE);
        mBackButton.setText(R.string.wifi_setup_back);

        final ViewGroup parent = (ViewGroup)findViewById(R.id.wifi_config_ui);
        parent.setVisibility(View.GONE);
        mConnectingStatusLayout.setVisibility(View.VISIBLE);
        mConnectingStatusView.setText(R.string.wifi_setup_description_connecting);

        mSkipOrNextButton.setVisibility(View.VISIBLE);
        mSkipOrNextButton.setEnabled(false);
        mConnectButton.setVisibility(View.GONE);
        mAddNetworkButton.setVisibility(View.GONE);
        mRefreshButton.setVisibility(View.GONE);
    }

    private void onBackButtonPressed() {

        if (mScreenState == SCREEN_STATE_CONNECTING || mScreenState == SCREEN_STATE_CONNECTED) {
            if (DEBUG) Log.d(TAG, "Back button pressed after connect action.");
            mScreenState = SCREEN_STATE_DISCONNECTED;

            // When a user press "Back" button after pressing "Connect" button, we want to cancel
            // the "Connect" request and refresh the whole Wifi status.
            restoreFirstVisibilityState();

            mSkipOrNextButton.setEnabled(true);
            changeNextButtonState(false);  // Skip

            // Wifi list becomes empty for a moment. We show "scanning" effect to a user so that
            // he/she won't be astonished there. This stops once the scan finishes.
            showScanningState();

            // Remembered networks may be re-used during SetupWizard, which confuse users.
            // We force the module to forget them to reduce UX complexity
            final List<WifiConfiguration> configs = mWifiManager.getConfiguredNetworks();
            for (WifiConfiguration config : configs) {
                if (DEBUG) {
                    Log.d(TAG, String.format("forgeting Wi-Fi network \"%s\" (id: %d)",
                            config.SSID, config.networkId));
                }
                mWifiManager.forget(mChannel, config.networkId, new WifiManager.ActionListener() {
                        public void onSuccess() {
                        }
                        public void onFailure(int reason) {
                            //TODO: Add failure UI
                        }
                        });
            }

            mWifiSettingsFragmentLayout.setVisibility(View.GONE);
            refreshAccessPoints(true);
        } else { // During user's Wifi configuration.
            mScreenState = SCREEN_STATE_DISCONNECTED;
            mWifiSettings.resumeWifiScan();

            restoreFirstVisibilityState();

            mAddNetworkButton.setEnabled(true);
            mRefreshButton.setEnabled(true);
            mSkipOrNextButton.setEnabled(true);
            showDisconnectedProgressBar();
            mWifiSettingsFragmentLayout.setVisibility(View.VISIBLE);
            mBottomPadding.setVisibility(View.GONE);
        }

        setPaddingVisibility(View.VISIBLE);
        mConnectingStatusLayout.setVisibility(View.GONE);
        final ViewGroup parent = (ViewGroup)findViewById(R.id.wifi_config_ui);
        parent.removeAllViews();
        parent.setVisibility(View.GONE);
        mWifiConfig = null;
    }

    /**
     * @param connected true when the device is connected to a specific network.
     */
    /* package */ void changeNextButtonState(boolean connected) {
        if (connected) {
            mSkipOrNextButton.setText(R.string.wifi_setup_next);
        } else {
            mSkipOrNextButton.setText(R.string.wifi_setup_skip);
        }
    }

    /**
     * Called when the list of AccessPoints are modified and this Activity needs to refresh
     * the list.
     * @param preferenceScreen
     */
    /* package */ void onAccessPointsUpdated(
            PreferenceScreen preferenceScreen, Collection<AccessPoint> accessPoints) {
        // If we already show some of access points but the bar still shows "scanning" state, it
        // should be stopped.
        if (mProgressBar.isIndeterminate() && accessPoints.size() > 0) {
            showDisconnectedProgressBar();
            if (mScreenState == SCREEN_STATE_DISCONNECTED) {
                mWifiSettingsFragmentLayout.setVisibility(View.VISIBLE);
                mBottomPadding.setVisibility(View.GONE);
            }
            mAddNetworkButton.setEnabled(true);
            mRefreshButton.setEnabled(true);
        }

        for (AccessPoint accessPoint : accessPoints) {
            accessPoint.setLayoutResource(R.layout.custom_preference);
            preferenceScreen.addPreference(accessPoint);
        }
    }

    private void refreshAccessPoints(boolean disconnectNetwork) {
        showScanningState();

        if (disconnectNetwork) {
            mWifiManager.disconnect();
        }

        mWifiSettings.refreshAccessPoints();
    }

    /**
     * Called when {@link WifiSettings} received
     * {@link WifiManager#SUPPLICANT_STATE_CHANGED_ACTION}.
     */
    /* package */ void onSupplicantStateChanged(Intent intent) {
        final int errorCode = intent.getIntExtra(WifiManager.EXTRA_SUPPLICANT_ERROR, -1);
        if (errorCode == WifiManager.ERROR_AUTHENTICATING) {
            Log.i(TAG, "Received authentication error event.");
            onAuthenticationFailure();
        }
    }

    /**
     * Called once when Authentication failed.
     */
    private void onAuthenticationFailure() {
        mScreenState = SCREEN_STATE_EDITING;

        mSkipOrNextButton.setVisibility(View.GONE);
        mConnectButton.setVisibility(View.VISIBLE);
        mConnectButton.setEnabled(true);

        if (!TextUtils.isEmpty(mEditingTitle)) {
            mTitleView.setText(mEditingTitle);
        } else {
            Log.w(TAG, "Title during editing/adding a network was empty.");
            showEditingTitle();
        }

        final ViewGroup parent = (ViewGroup)findViewById(R.id.wifi_config_ui);
        parent.setVisibility(View.VISIBLE);
        mConnectingStatusLayout.setVisibility(View.GONE);

        showDisconnectedProgressBar();
        setPaddingVisibility(View.GONE);
    }

    // Used by WifiConfigUiForSetupWizardXL
    /* package */ void setPaddingVisibility(int visibility) {
        mTopPadding.setVisibility(visibility);
        mContentPadding.setVisibility(visibility);
    }

    private void showDisconnectedProgressBar() {
        // The device may report DISCONNECTED during connecting to a network, at which we don't
        // want to lose bottom padding of top divider implicitly added by ProgressBar.
        if (mScreenState == SCREEN_STATE_DISCONNECTED) {
            mProgressBar.setVisibility(View.GONE);
            mProgressBar.setIndeterminate(false);
            mTopDividerNoProgress.setVisibility(View.VISIBLE);
        } else {
            mProgressBar.setVisibility(View.VISIBLE);
            mProgressBar.setIndeterminate(false);
            mProgressBar.setProgress(0);
            mTopDividerNoProgress.setVisibility(View.GONE);
        }
    }

    /**
     * Shows top divider with ProgressBar, whose state is intermediate.
     */
    private void showScanningProgressBar() {
        showTopDividerWithProgressBar();
        mProgressBar.setIndeterminate(true);
    }

    /**
     * Shows top divider with ProgressBar, showing "connecting" state.
     */
    private void showConnectingProgressBar() {
        showTopDividerWithProgressBar();
        mProgressBar.setIndeterminate(false);
        mProgressBar.setProgress(1);
    }

    private void showConnectedProgressBar() {
        showTopDividerWithProgressBar();
        mProgressBar.setIndeterminate(false);
        mProgressBar.setProgress(2);
    }

    /**
     * Called when WifiManager is requested to save a network.
     */
    /* package */ void onSaveNetwork(WifiConfiguration config) {
        // We want to both save and connect a network. connectNetwork() does both.
        mWifiManager.connect(mChannel, config, new WifiManager.ActionListener() {
                public void onSuccess() {
                }
                public void onFailure(int reason) {
                //TODO: Add failure UI
                }
                });
    }
}