xref: /packages/services/Telephony/src/com/android/phone/PhoneUtils.java

/*
 * Copyright (C) 2006 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.phone;

import android.app.AlertDialog;
import android.app.Dialog;
import android.app.ProgressDialog;
import android.bluetooth.IBluetoothHeadsetPhone;
import android.content.ActivityNotFoundException;
import android.content.ComponentName;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.res.Configuration;
import android.media.AudioManager;
import android.net.Uri;
import android.os.Handler;
import android.os.Message;
import android.os.PersistableBundle;
import android.os.RemoteException;
import android.os.SystemProperties;
import android.telecom.PhoneAccount;
import android.telecom.PhoneAccountHandle;
import android.telecom.VideoProfile;
import android.telephony.CarrierConfigManager;
import android.telephony.PhoneNumberUtils;
import android.telephony.SubscriptionManager;
import android.text.TextUtils;
import android.util.Log;
import android.view.ContextThemeWrapper;
import android.view.KeyEvent;
import android.view.LayoutInflater;
import android.view.View;
import android.view.WindowManager;
import android.widget.EditText;
import android.widget.Toast;

import com.android.internal.telephony.Call;
import com.android.internal.telephony.CallManager;
import com.android.internal.telephony.CallStateException;
import com.android.internal.telephony.CallerInfo;
import com.android.internal.telephony.CallerInfoAsyncQuery;
import com.android.internal.telephony.Connection;
import com.android.internal.telephony.IccCard;
import com.android.internal.telephony.MmiCode;
import com.android.internal.telephony.Phone;
import com.android.internal.telephony.PhoneConstants;
import com.android.internal.telephony.PhoneFactory;
import com.android.internal.telephony.TelephonyCapabilities;
import com.android.internal.telephony.TelephonyProperties;
import com.android.internal.telephony.sip.SipPhone;
import com.android.phone.CallGatewayManager.RawGatewayInfo;

import java.util.Arrays;
import java.util.List;

/**
 * Misc utilities for the Phone app.
 */
public class PhoneUtils {
    public static final String EMERGENCY_ACCOUNT_HANDLE_ID = "E";
    private static final String LOG_TAG = "PhoneUtils";
    private static final boolean DBG = (PhoneGlobals.DBG_LEVEL >= 2);

    // Do not check in with VDBG = true, since that may write PII to the system log.
    private static final boolean VDBG = false;

    /** Control stack trace for Audio Mode settings */
    private static final boolean DBG_SETAUDIOMODE_STACK = false;

    /** Identifier for the "Add Call" intent extra. */
    static final String ADD_CALL_MODE_KEY = "add_call_mode";

    // Return codes from placeCall()
    public static final int CALL_STATUS_DIALED = 0;  // The number was successfully dialed
    public static final int CALL_STATUS_DIALED_MMI = 1;  // The specified number was an MMI code
    public static final int CALL_STATUS_FAILED = 2;  // The call failed

    // State of the Phone's audio modes
    // Each state can move to the other states, but within the state only certain
    //  transitions for AudioManager.setMode() are allowed.
    static final int AUDIO_IDLE = 0;  /** audio behaviour at phone idle */
    static final int AUDIO_RINGING = 1;  /** audio behaviour while ringing */
    static final int AUDIO_OFFHOOK = 2;  /** audio behaviour while in call. */

    // USSD string length for MMI operations
    static final int MIN_USSD_LEN = 1;
    static final int MAX_USSD_LEN = 160;

    /** Speaker state, persisting between wired headset connection events */
    private static boolean sIsSpeakerEnabled = false;

    /** Static handler for the connection/mute tracking */
    private static ConnectionHandler mConnectionHandler;

    /** Phone state changed event*/
    private static final int PHONE_STATE_CHANGED = -1;

    /** check status then decide whether answerCall */
    private static final int MSG_CHECK_STATUS_ANSWERCALL = 100;

    /** poll phone DISCONNECTING status interval */
    private static final int DISCONNECTING_POLLING_INTERVAL_MS = 200;

    /** poll phone DISCONNECTING status times limit */
    private static final int DISCONNECTING_POLLING_TIMES_LIMIT = 8;

    /** Define for not a special CNAP string */
    private static final int CNAP_SPECIAL_CASE_NO = -1;

    /** Noise suppression status as selected by user */
    private static boolean sIsNoiseSuppressionEnabled = true;

    /**
     * Theme to use for dialogs displayed by utility methods in this class. This is needed
     * because these dialogs are displayed using the application context, which does not resolve
     * the dialog theme correctly.
     */
    private static final int THEME = AlertDialog.THEME_DEVICE_DEFAULT_LIGHT;

    private static class FgRingCalls {
        private Call fgCall;
        private Call ringing;
        public FgRingCalls(Call fg, Call ring) {
            fgCall = fg;
            ringing = ring;
        }
    }

    /** USSD information used to aggregate all USSD messages */
    private static AlertDialog sUssdDialog = null;
    private static StringBuilder sUssdMsg = new StringBuilder();

    private static final ComponentName PSTN_CONNECTION_SERVICE_COMPONENT =
            new ComponentName("com.android.phone",
                    "com.android.services.telephony.TelephonyConnectionService");

    /**
     * Handler that tracks the connections and updates the value of the
     * Mute settings for each connection as needed.
     */
    private static class ConnectionHandler extends Handler {
        @Override
        public void handleMessage(Message msg) {
            switch (msg.what) {
                case MSG_CHECK_STATUS_ANSWERCALL:
                    FgRingCalls frC = (FgRingCalls) msg.obj;
                    // wait for finishing disconnecting
                    // before check the ringing call state
                    if ((frC.fgCall != null) &&
                        (frC.fgCall.getState() == Call.State.DISCONNECTING) &&
                        (msg.arg1 < DISCONNECTING_POLLING_TIMES_LIMIT)) {
                        Message retryMsg =
                            mConnectionHandler.obtainMessage(MSG_CHECK_STATUS_ANSWERCALL);
                        retryMsg.arg1 = 1 + msg.arg1;
                        retryMsg.obj = msg.obj;
                        mConnectionHandler.sendMessageDelayed(retryMsg,
                            DISCONNECTING_POLLING_INTERVAL_MS);
                    // since hangupActiveCall() also accepts the ringing call
                    // check if the ringing call was already answered or not
                    // only answer it when the call still is ringing
                    } else if (frC.ringing.isRinging()) {
                        if (msg.arg1 == DISCONNECTING_POLLING_TIMES_LIMIT) {
                            Log.e(LOG_TAG, "DISCONNECTING time out");
                        }
                        answerCall(frC.ringing);
                    }
                    break;
            }
        }
    }

    /**
     * Register the ConnectionHandler with the phone, to receive connection events
     */
    public static void initializeConnectionHandler(CallManager cm) {
        if (mConnectionHandler == null) {
            mConnectionHandler = new ConnectionHandler();
        }

        // pass over cm as user.obj
        cm.registerForPreciseCallStateChanged(mConnectionHandler, PHONE_STATE_CHANGED, cm);

    }

    /** This class is never instantiated. */
    private PhoneUtils() {
    }

    /**
     * Answer the currently-ringing call.
     *
     * @return true if we answered the call, or false if there wasn't
     *         actually a ringing incoming call, or some other error occurred.
     *
     * @see #answerAndEndHolding(CallManager, Call)
     * @see #answerAndEndActive(CallManager, Call)
     */
    /* package */ static boolean answerCall(Call ringingCall) {
        log("answerCall(" + ringingCall + ")...");
        final PhoneGlobals app = PhoneGlobals.getInstance();
        final CallNotifier notifier = app.notifier;

        final Phone phone = ringingCall.getPhone();
        final boolean phoneIsCdma = (phone.getPhoneType() == PhoneConstants.PHONE_TYPE_CDMA);
        boolean answered = false;
        IBluetoothHeadsetPhone btPhone = null;

        if (phoneIsCdma) {
            // Stop any signalInfo tone being played when a Call waiting gets answered
            if (ringingCall.getState() == Call.State.WAITING) {
                notifier.stopSignalInfoTone();
            }
        }

        if (ringingCall != null && ringingCall.isRinging()) {
            if (DBG) log("answerCall: call state = " + ringingCall.getState());
            try {
                if (phoneIsCdma) {
                    if (app.cdmaPhoneCallState.getCurrentCallState()
                            == CdmaPhoneCallState.PhoneCallState.IDLE) {
                        // This is the FIRST incoming call being answered.
                        // Set the Phone Call State to SINGLE_ACTIVE
                        app.cdmaPhoneCallState.setCurrentCallState(
                                CdmaPhoneCallState.PhoneCallState.SINGLE_ACTIVE);
                    } else {
                        // This is the CALL WAITING call being answered.
                        // Set the Phone Call State to CONF_CALL
                        app.cdmaPhoneCallState.setCurrentCallState(
                                CdmaPhoneCallState.PhoneCallState.CONF_CALL);
                        // Enable "Add Call" option after answering a Call Waiting as the user
                        // should be allowed to add another call in case one of the parties
                        // drops off
                        app.cdmaPhoneCallState.setAddCallMenuStateAfterCallWaiting(true);
                    }
                }

                final boolean isRealIncomingCall = isRealIncomingCall(ringingCall.getState());

                //if (DBG) log("sPhone.acceptCall");
                app.mCM.acceptCall(ringingCall);
                answered = true;

                setAudioMode();
            } catch (CallStateException ex) {
                Log.w(LOG_TAG, "answerCall: caught " + ex, ex);

                if (phoneIsCdma) {
                    // restore the cdmaPhoneCallState and btPhone.cdmaSetSecondCallState:
                    app.cdmaPhoneCallState.setCurrentCallState(
                            app.cdmaPhoneCallState.getPreviousCallState());
                    if (btPhone != null) {
                        try {
                            btPhone.cdmaSetSecondCallState(false);
                        } catch (RemoteException e) {
                            Log.e(LOG_TAG, Log.getStackTraceString(new Throwable()));
                        }
                    }
                }
            }
        }
        return answered;
    }

    /**
     * Hangs up all active calls.
     */
    static void hangupAllCalls(CallManager cm) {
        final Call ringing = cm.getFirstActiveRingingCall();
        final Call fg = cm.getActiveFgCall();
        final Call bg = cm.getFirstActiveBgCall();

        // We go in reverse order, BG->FG->RINGING because hanging up a ringing call or an active
        // call can move a bg call to a fg call which would force us to loop over each call
        // several times.  This ordering works best to ensure we dont have any more calls.
        if (bg != null && !bg.isIdle()) {
            hangup(bg);
        }
        if (fg != null && !fg.isIdle()) {
            hangup(fg);
        }
        if (ringing != null && !ringing.isIdle()) {
            hangupRingingCall(fg);
        }
    }

    /**
     * Smart "hang up" helper method which hangs up exactly one connection,
     * based on the current Phone state, as follows:
     * <ul>
     * <li>If there's a ringing call, hang that up.
     * <li>Else if there's a foreground call, hang that up.
     * <li>Else if there's a background call, hang that up.
     * <li>Otherwise do nothing.
     * </ul>
     * @return true if we successfully hung up, or false
     *              if there were no active calls at all.
     */
    static boolean hangup(CallManager cm) {
        boolean hungup = false;
        Call ringing = cm.getFirstActiveRingingCall();
        Call fg = cm.getActiveFgCall();
        Call bg = cm.getFirstActiveBgCall();

        if (!ringing.isIdle()) {
            log("hangup(): hanging up ringing call");
            hungup = hangupRingingCall(ringing);
        } else if (!fg.isIdle()) {
            log("hangup(): hanging up foreground call");
            hungup = hangup(fg);
        } else if (!bg.isIdle()) {
            log("hangup(): hanging up background call");
            hungup = hangup(bg);
        } else {
            // No call to hang up!  This is unlikely in normal usage,
            // since the UI shouldn't be providing an "End call" button in
            // the first place.  (But it *can* happen, rarely, if an
            // active call happens to disconnect on its own right when the
            // user is trying to hang up..)
            log("hangup(): no active call to hang up");
        }
        if (DBG) log("==> hungup = " + hungup);

        return hungup;
    }

    static boolean hangupRingingCall(Call ringing) {
        if (DBG) log("hangup ringing call");
        int phoneType = ringing.getPhone().getPhoneType();
        Call.State state = ringing.getState();

        if (state == Call.State.INCOMING) {
            // Regular incoming call (with no other active calls)
            log("hangupRingingCall(): regular incoming call: hangup()");
            return hangup(ringing);
        } else {
            // Unexpected state: the ringing call isn't INCOMING or
            // WAITING, so there's no reason to have called
            // hangupRingingCall() in the first place.
            // (Presumably the incoming call went away at the exact moment
            // we got here, so just do nothing.)
            Log.w(LOG_TAG, "hangupRingingCall: no INCOMING or WAITING call");
            return false;
        }
    }

    static boolean hangupActiveCall(Call foreground) {
        if (DBG) log("hangup active call");
        return hangup(foreground);
    }

    static boolean hangupHoldingCall(Call background) {
        if (DBG) log("hangup holding call");
        return hangup(background);
    }

    /**
     * Used in CDMA phones to end the complete Call session
     * @param phone the Phone object.
     * @return true if *any* call was successfully hung up
     */
    static boolean hangupRingingAndActive(Phone phone) {
        boolean hungUpRingingCall = false;
        boolean hungUpFgCall = false;
        Call ringingCall = phone.getRingingCall();
        Call fgCall = phone.getForegroundCall();

        // Hang up any Ringing Call
        if (!ringingCall.isIdle()) {
            log("hangupRingingAndActive: Hang up Ringing Call");
            hungUpRingingCall = hangupRingingCall(ringingCall);
        }

        // Hang up any Active Call
        if (!fgCall.isIdle()) {
            log("hangupRingingAndActive: Hang up Foreground Call");
            hungUpFgCall = hangupActiveCall(fgCall);
        }

        return hungUpRingingCall || hungUpFgCall;
    }

    /**
     * Trivial wrapper around Call.hangup(), except that we return a
     * boolean success code rather than throwing CallStateException on
     * failure.
     *
     * @return true if the call was successfully hung up, or false
     *         if the call wasn't actually active.
     */
    static boolean hangup(Call call) {
        try {
            CallManager cm = PhoneGlobals.getInstance().mCM;

            if (call.getState() == Call.State.ACTIVE && cm.hasActiveBgCall()) {
                // handle foreground call hangup while there is background call
                log("- hangup(Call): hangupForegroundResumeBackground...");
                cm.hangupForegroundResumeBackground(cm.getFirstActiveBgCall());
            } else {
                log("- hangup(Call): regular hangup()...");
                call.hangup();
            }
            return true;
        } catch (CallStateException ex) {
            Log.e(LOG_TAG, "Call hangup: caught " + ex, ex);
        }

        return false;
    }

    /**
     * Trivial wrapper around Connection.hangup(), except that we silently
     * do nothing (rather than throwing CallStateException) if the
     * connection wasn't actually active.
     */
    static void hangup(Connection c) {
        try {
            if (c != null) {
                c.hangup();
            }
        } catch (CallStateException ex) {
            Log.w(LOG_TAG, "Connection hangup: caught " + ex, ex);
        }
    }

    static boolean answerAndEndHolding(CallManager cm, Call ringing) {
        if (DBG) log("end holding & answer waiting: 1");
        if (!hangupHoldingCall(cm.getFirstActiveBgCall())) {
            Log.e(LOG_TAG, "end holding failed!");
            return false;
        }

        if (DBG) log("end holding & answer waiting: 2");
        return answerCall(ringing);

    }

    /**
     * Answers the incoming call specified by "ringing", and ends the currently active phone call.
     *
     * This method is useful when's there's an incoming call which we cannot manage with the
     * current call. e.g. when you are having a phone call with CDMA network and has received
     * a SIP call, then we won't expect our telephony can manage those phone calls simultaneously.
     * Note that some types of network may allow multiple phone calls at once; GSM allows to hold
     * an ongoing phone call, so we don't need to end the active call. The caller of this method
     * needs to check if the network allows multiple phone calls or not.
     *
     * @see #answerCall(Call)
     * @see InCallScreen#internalAnswerCall()
     */
    /* package */ static boolean answerAndEndActive(CallManager cm, Call ringing) {
        if (DBG) log("answerAndEndActive()...");

        // Unlike the answerCall() method, we *don't* need to stop the
        // ringer or change audio modes here since the user is already
        // in-call, which means that the audio mode is already set
        // correctly, and that we wouldn't have started the ringer in the
        // first place.

        // hanging up the active call also accepts the waiting call
        // while active call and waiting call are from the same phone
        // i.e. both from GSM phone
        Call fgCall = cm.getActiveFgCall();
        if (!hangupActiveCall(fgCall)) {
            Log.w(LOG_TAG, "end active call failed!");
            return false;
        }

        mConnectionHandler.removeMessages(MSG_CHECK_STATUS_ANSWERCALL);
        Message msg = mConnectionHandler.obtainMessage(MSG_CHECK_STATUS_ANSWERCALL);
        msg.arg1 = 1;
        msg.obj = new FgRingCalls(fgCall, ringing);
        mConnectionHandler.sendMessage(msg);

        return true;
    }

    /**
     * For a CDMA phone, advance the call state upon making a new
     * outgoing call.
     *
     * <pre>
     *   IDLE -> SINGLE_ACTIVE
     * or
     *   SINGLE_ACTIVE -> THRWAY_ACTIVE
     * </pre>
     * @param app The phone instance.
     */
    private static void updateCdmaCallStateOnNewOutgoingCall(PhoneGlobals app,
            Connection connection) {
        if (app.cdmaPhoneCallState.getCurrentCallState() ==
            CdmaPhoneCallState.PhoneCallState.IDLE) {
            // This is the first outgoing call. Set the Phone Call State to ACTIVE
            app.cdmaPhoneCallState.setCurrentCallState(
                CdmaPhoneCallState.PhoneCallState.SINGLE_ACTIVE);
        } else {
            // This is the second outgoing call. Set the Phone Call State to 3WAY
            app.cdmaPhoneCallState.setCurrentCallState(
                CdmaPhoneCallState.PhoneCallState.THRWAY_ACTIVE);

            // TODO: Remove this code.
            //app.getCallModeler().setCdmaOutgoing3WayCall(connection);
        }
    }

    /**
     * @see placeCall below
     */
    public static int placeCall(Context context, Phone phone, String number, Uri contactRef,
            boolean isEmergencyCall) {
        return placeCall(context, phone, number, contactRef, isEmergencyCall,
                CallGatewayManager.EMPTY_INFO, null);
    }

    /**
     * Dial the number using the phone passed in.
     *
     * If the connection is establised, this method issues a sync call
     * that may block to query the caller info.
     * TODO: Change the logic to use the async query.
     *
     * @param context To perform the CallerInfo query.
     * @param phone the Phone object.
     * @param number to be dialed as requested by the user. This is
     * NOT the phone number to connect to. It is used only to build the
     * call card and to update the call log. See above for restrictions.
     * @param contactRef that triggered the call. Typically a 'tel:'
     * uri but can also be a 'content://contacts' one.
     * @param isEmergencyCall indicates that whether or not this is an
     * emergency call
     * @param gatewayUri Is the address used to setup the connection, null
     * if not using a gateway
     * @param callGateway Class for setting gateway data on a successful call.
     *
     * @return either CALL_STATUS_DIALED or CALL_STATUS_FAILED
     */
    public static int placeCall(Context context, Phone phone, String number, Uri contactRef,
            boolean isEmergencyCall, RawGatewayInfo gatewayInfo, CallGatewayManager callGateway) {
        final Uri gatewayUri = gatewayInfo.gatewayUri;

        if (VDBG) {
            log("placeCall()... number: '" + number + "'"
                    + ", GW:'" + gatewayUri + "'"
                    + ", contactRef:" + contactRef
                    + ", isEmergencyCall: " + isEmergencyCall);
        } else {
            log("placeCall()... number: " + toLogSafePhoneNumber(number)
                    + ", GW: " + (gatewayUri != null ? "non-null" : "null")
                    + ", emergency? " + isEmergencyCall);
        }
        final PhoneGlobals app = PhoneGlobals.getInstance();

        boolean useGateway = false;
        if (null != gatewayUri &&
            !isEmergencyCall &&
            PhoneUtils.isRoutableViaGateway(number)) {  // Filter out MMI, OTA and other codes.
            useGateway = true;
        }

        int status = CALL_STATUS_DIALED;
        Connection connection;
        String numberToDial;
        if (useGateway) {
            // TODO: 'tel' should be a constant defined in framework base
            // somewhere (it is in webkit.)
            if (null == gatewayUri || !PhoneAccount.SCHEME_TEL.equals(gatewayUri.getScheme())) {
                Log.e(LOG_TAG, "Unsupported URL:" + gatewayUri);
                return CALL_STATUS_FAILED;
            }

            // We can use getSchemeSpecificPart because we don't allow #
            // in the gateway numbers (treated a fragment delim.) However
            // if we allow more complex gateway numbers sequence (with
            // passwords or whatnot) that use #, this may break.
            // TODO: Need to support MMI codes.
            numberToDial = gatewayUri.getSchemeSpecificPart();
        } else {
            numberToDial = number;
        }

        // Remember if the phone state was in IDLE state before this call.
        // After calling CallManager#dial(), getState() will return different state.
        final boolean initiallyIdle = app.mCM.getState() == PhoneConstants.State.IDLE;

        try {
            connection = app.mCM.dial(phone, numberToDial, VideoProfile.STATE_AUDIO_ONLY);
        } catch (CallStateException ex) {
            // CallStateException means a new outgoing call is not currently
            // possible: either no more call slots exist, or there's another
            // call already in the process of dialing or ringing.
            Log.w(LOG_TAG, "Exception from app.mCM.dial()", ex);
            return CALL_STATUS_FAILED;

            // Note that it's possible for CallManager.dial() to return
            // null *without* throwing an exception; that indicates that
            // we dialed an MMI (see below).
        }

        int phoneType = phone.getPhoneType();

        // On GSM phones, null is returned for MMI codes
        if (null == connection) {
            status = CALL_STATUS_FAILED;
        } else {
            // Now that the call is successful, we can save the gateway info for the call
            if (callGateway != null) {
                callGateway.setGatewayInfoForConnection(connection, gatewayInfo);
            }

            if (phoneType == PhoneConstants.PHONE_TYPE_CDMA) {
                updateCdmaCallStateOnNewOutgoingCall(app, connection);
            }

            if (gatewayUri == null) {
                // phone.dial() succeeded: we're now in a normal phone call.
                // attach the URI to the CallerInfo Object if it is there,
                // otherwise just attach the Uri Reference.
                // if the uri does not have a "content" scheme, then we treat
                // it as if it does NOT have a unique reference.
                String content = context.getContentResolver().SCHEME_CONTENT;
                if ((contactRef != null) && (contactRef.getScheme().equals(content))) {
                    Object userDataObject = connection.getUserData();
                    if (userDataObject == null) {
                        connection.setUserData(contactRef);
                    } else {
                        // TODO: This branch is dead code, we have
                        // just created the connection which has
                        // no user data (null) by default.
                        if (userDataObject instanceof CallerInfo) {
                        ((CallerInfo) userDataObject).contactRefUri = contactRef;
                        } else {
                        ((CallerInfoToken) userDataObject).currentInfo.contactRefUri =
                            contactRef;
                        }
                    }
                }
            }

            startGetCallerInfo(context, connection, null, null, gatewayInfo);

            setAudioMode();
        }

        return status;
    }

    /* package */ static String toLogSafePhoneNumber(String number) {
        // For unknown number, log empty string.
        if (number == null) {
            return "";
        }

        if (VDBG) {
            // When VDBG is true we emit PII.
            return number;
        }

        // Do exactly same thing as Uri#toSafeString() does, which will enable us to compare
        // sanitized phone numbers.
        StringBuilder builder = new StringBuilder();
        for (int i = 0; i < number.length(); i++) {
            char c = number.charAt(i);
            if (c == '-' || c == '@' || c == '.') {
                builder.append(c);
            } else {
                builder.append('x');
            }
        }
        return builder.toString();
    }

    /**
     * Wrapper function to control when to send an empty Flash command to the network.
     * Mainly needed for CDMA networks, such as scenarios when we need to send a blank flash
     * to the network prior to placing a 3-way call for it to be successful.
     */
    static void sendEmptyFlash(Phone phone) {
        if (phone.getPhoneType() == PhoneConstants.PHONE_TYPE_CDMA) {
            Call fgCall = phone.getForegroundCall();
            if (fgCall.getState() == Call.State.ACTIVE) {
                // Send the empty flash
                if (DBG) Log.d(LOG_TAG, "onReceive: (CDMA) sending empty flash to network");
                switchHoldingAndActive(phone.getBackgroundCall());
            }
        }
    }

    static void swap() {
        final PhoneGlobals mApp = PhoneGlobals.getInstance();
        if (!okToSwapCalls(mApp.mCM)) {
            // TODO: throw an error instead?
            return;
        }

        // Swap the fg and bg calls.
        // In the future we may provide some way for user to choose among
        // multiple background calls, for now, always act on the first background call.
        PhoneUtils.switchHoldingAndActive(mApp.mCM.getFirstActiveBgCall());
    }

    /**
     * @param heldCall is the background call want to be swapped
     */
    static void switchHoldingAndActive(Call heldCall) {
        log("switchHoldingAndActive()...");
        try {
            CallManager cm = PhoneGlobals.getInstance().mCM;
            if (heldCall.isIdle()) {
                // no heldCall, so it is to hold active call
                cm.switchHoldingAndActive(cm.getFgPhone().getBackgroundCall());
            } else {
                // has particular heldCall, so to switch
                cm.switchHoldingAndActive(heldCall);
            }
            setAudioMode(cm);
        } catch (CallStateException ex) {
            Log.w(LOG_TAG, "switchHoldingAndActive: caught " + ex, ex);
        }
    }

    static void mergeCalls() {
        mergeCalls(PhoneGlobals.getInstance().mCM);
    }

    static void mergeCalls(CallManager cm) {
        int phoneType = cm.getFgPhone().getPhoneType();
        if (phoneType == PhoneConstants.PHONE_TYPE_CDMA) {
            log("mergeCalls(): CDMA...");
            PhoneGlobals app = PhoneGlobals.getInstance();
            if (app.cdmaPhoneCallState.getCurrentCallState()
                    == CdmaPhoneCallState.PhoneCallState.THRWAY_ACTIVE) {
                // Set the Phone Call State to conference
                app.cdmaPhoneCallState.setCurrentCallState(
                        CdmaPhoneCallState.PhoneCallState.CONF_CALL);

                // Send flash cmd
                // TODO: Need to change the call from switchHoldingAndActive to
                // something meaningful as we are not actually trying to swap calls but
                // instead are merging two calls by sending a Flash command.
                log("- sending flash...");
                switchHoldingAndActive(cm.getFirstActiveBgCall());
            }
        } else {
            try {
                log("mergeCalls(): calling cm.conference()...");
                cm.conference(cm.getFirstActiveBgCall());
            } catch (CallStateException ex) {
                Log.w(LOG_TAG, "mergeCalls: caught " + ex, ex);
            }
        }
    }

    static void separateCall(Connection c) {
        try {
            if (DBG) log("separateCall: " + toLogSafePhoneNumber(c.getAddress()));
            c.separate();
        } catch (CallStateException ex) {
            Log.w(LOG_TAG, "separateCall: caught " + ex, ex);
        }
    }

    /**
     * Handle the MMIInitiate message and put up an alert that lets
     * the user cancel the operation, if applicable.
     *
     * @param context context to get strings.
     * @param mmiCode the MmiCode object being started.
     * @param buttonCallbackMessage message to post when button is clicked.
     * @param previousAlert a previous alert used in this activity.
     * @return the dialog handle
     */
    static Dialog displayMMIInitiate(Context context,
                                          MmiCode mmiCode,
                                          Message buttonCallbackMessage,
                                          Dialog previousAlert) {
        log("displayMMIInitiate: " + android.telecom.Log.pii(mmiCode.toString()));
        if (previousAlert != null) {
            previousAlert.dismiss();
        }

        // The UI paradigm we are using now requests that all dialogs have
        // user interaction, and that any other messages to the user should
        // be by way of Toasts.
        //
        // In adhering to this request, all MMI initiating "OK" dialogs
        // (non-cancelable MMIs) that end up being closed when the MMI
        // completes (thereby showing a completion dialog) are being
        // replaced with Toasts.
        //
        // As a side effect, moving to Toasts for the non-cancelable MMIs
        // also means that buttonCallbackMessage (which was tied into "OK")
        // is no longer invokable for these dialogs.  This is not a problem
        // since the only callback messages we supported were for cancelable
        // MMIs anyway.
        //
        // A cancelable MMI is really just a USSD request. The term
        // "cancelable" here means that we can cancel the request when the
        // system prompts us for a response, NOT while the network is
        // processing the MMI request.  Any request to cancel a USSD while
        // the network is NOT ready for a response may be ignored.
        //
        // With this in mind, we replace the cancelable alert dialog with
        // a progress dialog, displayed until we receive a request from
        // the the network.  For more information, please see the comments
        // in the displayMMIComplete() method below.
        //
        // Anything that is NOT a USSD request is a normal MMI request,
        // which will bring up a toast (desribed above).

        boolean isCancelable = (mmiCode != null) && mmiCode.isCancelable();

        if (!isCancelable) {
            log("displayMMIInitiate: not a USSD code, displaying status toast.");
            CharSequence text = context.getText(R.string.mmiStarted);
            Toast.makeText(context, text, Toast.LENGTH_SHORT)
                .show();
            return null;
        } else {
            log("displayMMIInitiate: running USSD code, displaying intermediate progress.");

            // create the indeterminate progress dialog and display it.
            ProgressDialog pd = new ProgressDialog(context, THEME);
            pd.setMessage(context.getText(R.string.ussdRunning));
            pd.setCancelable(false);
            pd.setIndeterminate(true);
            pd.getWindow().addFlags(WindowManager.LayoutParams.FLAG_DIM_BEHIND);

            pd.show();

            return pd;
        }

    }

    /**
     * Handle the MMIComplete message and fire off an intent to display
     * the message.
     *
     * @param context context to get strings.
     * @param mmiCode MMI result.
     * @param previousAlert a previous alert used in this activity.
     */
    static void displayMMIComplete(final Phone phone, Context context, final MmiCode mmiCode,
            Message dismissCallbackMessage,
            AlertDialog previousAlert) {
        final PhoneGlobals app = PhoneGlobals.getInstance();
        CharSequence text;
        int title = 0;  // title for the progress dialog, if needed.
        MmiCode.State state = mmiCode.getState();

        log("displayMMIComplete: state=" + state);

        switch (state) {
            case PENDING:
                // USSD code asking for feedback from user.
                text = mmiCode.getMessage();
                log("displayMMIComplete: using text from PENDING MMI message: '" + text + "'");
                break;
            case CANCELLED:
                text = null;
                break;
            case COMPLETE:
                if (app.getPUKEntryActivity() != null) {
                    // if an attempt to unPUK the device was made, we specify
                    // the title and the message here.
                    title = com.android.internal.R.string.PinMmi;
                    text = context.getText(R.string.puk_unlocked);
                    break;
                }
                // All other conditions for the COMPLETE mmi state will cause
                // the case to fall through to message logic in common with
                // the FAILED case.

            case FAILED:
                text = mmiCode.getMessage();
                log("displayMMIComplete (failed): using text from MMI message: '" + text + "'");
                break;
            default:
                throw new IllegalStateException("Unexpected MmiCode state: " + state);
        }

        if (previousAlert != null) {
            previousAlert.dismiss();
        }

        // Check to see if a UI exists for the PUK activation.  If it does
        // exist, then it indicates that we're trying to unblock the PUK.
        if ((app.getPUKEntryActivity() != null) && (state == MmiCode.State.COMPLETE)) {
            if (DBG) log("displaying PUK unblocking progress dialog.");

            // create the progress dialog, make sure the flags and type are
            // set correctly.
            ProgressDialog pd = new ProgressDialog(app, THEME);
            pd.setTitle(title);
            pd.setMessage(text);
            pd.setCancelable(false);
            pd.setIndeterminate(true);
            pd.getWindow().setType(WindowManager.LayoutParams.TYPE_SYSTEM_DIALOG);
            pd.getWindow().addFlags(WindowManager.LayoutParams.FLAG_DIM_BEHIND);

            // display the dialog
            pd.show();

            // indicate to the Phone app that the progress dialog has
            // been assigned for the PUK unlock / SIM READY process.
            app.setPukEntryProgressDialog(pd);

        } else {
            // In case of failure to unlock, we'll need to reset the
            // PUK unlock activity, so that the user may try again.
            if (app.getPUKEntryActivity() != null) {
                app.setPukEntryActivity(null);
            }

            // A USSD in a pending state means that it is still
            // interacting with the user.
            if (state != MmiCode.State.PENDING) {
                log("displayMMIComplete: MMI code has finished running.");

                log("displayMMIComplete: Extended NW displayMMIInitiate (" + text + ")");
                if (text == null || text.length() == 0)
                    return;

                // displaying system alert dialog on the screen instead of
                // using another activity to display the message.  This
                // places the message at the forefront of the UI.

                if (sUssdDialog == null) {
                    sUssdDialog = new AlertDialog.Builder(context, THEME)
                            .setPositiveButton(R.string.ok, null)
                            .setCancelable(true)
                            .setOnDismissListener(new DialogInterface.OnDismissListener() {
                                @Override
                                public void onDismiss(DialogInterface dialog) {
                                    sUssdMsg.setLength(0);
                                }
                            })
                            .create();

                    sUssdDialog.getWindow().setType(
                            WindowManager.LayoutParams.TYPE_SYSTEM_ALERT);
                    sUssdDialog.getWindow().addFlags(
                            WindowManager.LayoutParams.FLAG_DIM_BEHIND);
                }
                if (sUssdMsg.length() != 0) {
                    sUssdMsg
                            .insert(0, "\n")
                            .insert(0, app.getResources().getString(R.string.ussd_dialog_sep))
                            .insert(0, "\n");
                }
                sUssdMsg.insert(0, text);
                sUssdDialog.setMessage(sUssdMsg.toString());
                sUssdDialog.show();
            } else {
                log("displayMMIComplete: USSD code has requested user input. Constructing input "
                        + "dialog.");

                // USSD MMI code that is interacting with the user.  The
                // basic set of steps is this:
                //   1. User enters a USSD request
                //   2. We recognize the request and displayMMIInitiate
                //      (above) creates a progress dialog.
                //   3. Request returns and we get a PENDING or COMPLETE
                //      message.
                //   4. These MMI messages are caught in the PhoneApp
                //      (onMMIComplete) and the InCallScreen
                //      (mHandler.handleMessage) which bring up this dialog
                //      and closes the original progress dialog,
                //      respectively.
                //   5. If the message is anything other than PENDING,
                //      we are done, and the alert dialog (directly above)
                //      displays the outcome.
                //   6. If the network is requesting more information from
                //      the user, the MMI will be in a PENDING state, and
                //      we display this dialog with the message.
                //   7. User input, or cancel requests result in a return
                //      to step 1.  Keep in mind that this is the only
                //      time that a USSD should be canceled.

                // inflate the layout with the scrolling text area for the dialog.
                ContextThemeWrapper contextThemeWrapper =
                        new ContextThemeWrapper(context, R.style.DialerAlertDialogTheme);
                LayoutInflater inflater = (LayoutInflater) contextThemeWrapper.getSystemService(
                        Context.LAYOUT_INFLATER_SERVICE);
                View dialogView = inflater.inflate(R.layout.dialog_ussd_response, null);

                // get the input field.
                final EditText inputText = (EditText) dialogView.findViewById(R.id.input_field);

                // specify the dialog's click listener, with SEND and CANCEL logic.
                final DialogInterface.OnClickListener mUSSDDialogListener =
                    new DialogInterface.OnClickListener() {
                        public void onClick(DialogInterface dialog, int whichButton) {
                            switch (whichButton) {
                                case DialogInterface.BUTTON_POSITIVE:
                                    // As per spec 24.080, valid length of ussd string
                                    // is 1 - 160. If length is out of the range then
                                    // display toast message & Cancel MMI operation.
                                    if (inputText.length() < MIN_USSD_LEN
                                            || inputText.length() > MAX_USSD_LEN) {
                                        Toast.makeText(app,
                                                app.getResources().getString(R.string.enter_input,
                                                MIN_USSD_LEN, MAX_USSD_LEN),
                                                Toast.LENGTH_LONG).show();
                                        if (mmiCode.isCancelable()) {
                                            mmiCode.cancel();
                                        }
                                    } else {
                                        phone.sendUssdResponse(inputText.getText().toString());
                                    }
                                    break;
                                case DialogInterface.BUTTON_NEGATIVE:
                                    if (mmiCode.isCancelable()) {
                                        mmiCode.cancel();
                                    }
                                    break;
                            }
                        }
                    };

                // build the dialog
                final AlertDialog newDialog = new AlertDialog.Builder(contextThemeWrapper)
                        .setMessage(text)
                        .setView(dialogView)
                        .setPositiveButton(R.string.send_button, mUSSDDialogListener)
                        .setNegativeButton(R.string.cancel, mUSSDDialogListener)
                        .setCancelable(false)
                        .create();

                // attach the key listener to the dialog's input field and make
                // sure focus is set.
                final View.OnKeyListener mUSSDDialogInputListener =
                    new View.OnKeyListener() {
                        public boolean onKey(View v, int keyCode, KeyEvent event) {
                            switch (keyCode) {
                                case KeyEvent.KEYCODE_CALL:
                                case KeyEvent.KEYCODE_ENTER:
                                    if(event.getAction() == KeyEvent.ACTION_DOWN) {
                                        phone.sendUssdResponse(inputText.getText().toString());
                                        newDialog.dismiss();
                                    }
                                    return true;
                            }
                            return false;
                        }
                    };
                inputText.setOnKeyListener(mUSSDDialogInputListener);
                inputText.requestFocus();

                // set the window properties of the dialog
                newDialog.getWindow().setType(
                        WindowManager.LayoutParams.TYPE_SYSTEM_DIALOG);
                newDialog.getWindow().addFlags(
                        WindowManager.LayoutParams.FLAG_DIM_BEHIND);

                // now show the dialog!
                newDialog.show();

                newDialog.getButton(DialogInterface.BUTTON_POSITIVE)
                        .setTextColor(context.getResources().getColor(R.color.dialer_theme_color));
                newDialog.getButton(DialogInterface.BUTTON_NEGATIVE)
                        .setTextColor(context.getResources().getColor(R.color.dialer_theme_color));
            }
        }
    }

    /**
     * Cancels the current pending MMI operation, if applicable.
     * @return true if we canceled an MMI operation, or false
     *         if the current pending MMI wasn't cancelable
     *         or if there was no current pending MMI at all.
     *
     * @see displayMMIInitiate
     */
    static boolean cancelMmiCode(Phone phone) {
        List<? extends MmiCode> pendingMmis = phone.getPendingMmiCodes();
        int count = pendingMmis.size();
        if (DBG) log("cancelMmiCode: num pending MMIs = " + count);

        boolean canceled = false;
        if (count > 0) {
            // assume that we only have one pending MMI operation active at a time.
            // I don't think it's possible to enter multiple MMI codes concurrently
            // in the phone UI, because during the MMI operation, an Alert panel
            // is displayed, which prevents more MMI code from being entered.
            MmiCode mmiCode = pendingMmis.get(0);
            if (mmiCode.isCancelable()) {
                mmiCode.cancel();
                canceled = true;
            }
        }
        return canceled;
    }

    public static class VoiceMailNumberMissingException extends Exception {
        VoiceMailNumberMissingException() {
            super();
        }

        VoiceMailNumberMissingException(String msg) {
            super(msg);
        }
    }

    /**
     * Given an Intent (which is presumably the ACTION_CALL intent that
     * initiated this outgoing call), figure out the actual phone number we
     * should dial.
     *
     * Note that the returned "number" may actually be a SIP address,
     * if the specified intent contains a sip: URI.
     *
     * This method is basically a wrapper around PhoneUtils.getNumberFromIntent(),
     * except it's also aware of the EXTRA_ACTUAL_NUMBER_TO_DIAL extra.
     * (That extra, if present, tells us the exact string to pass down to the
     * telephony layer.  It's guaranteed to be safe to dial: it's either a PSTN
     * phone number with separators and keypad letters stripped out, or a raw
     * unencoded SIP address.)
     *
     * @return the phone number corresponding to the specified Intent, or null
     *   if the Intent has no action or if the intent's data is malformed or
     *   missing.
     *
     * @throws VoiceMailNumberMissingException if the intent
     *   contains a "voicemail" URI, but there's no voicemail
     *   number configured on the device.
     */
    public static String getInitialNumber(Intent intent)
            throws PhoneUtils.VoiceMailNumberMissingException {
        if (DBG) log("getInitialNumber(): " + intent);

        String action = intent.getAction();
        if (TextUtils.isEmpty(action)) {
            return null;
        }

        // If the EXTRA_ACTUAL_NUMBER_TO_DIAL extra is present, get the phone
        // number from there.  (That extra takes precedence over the actual data
        // included in the intent.)
        if (intent.hasExtra(OutgoingCallBroadcaster.EXTRA_ACTUAL_NUMBER_TO_DIAL)) {
            String actualNumberToDial =
                    intent.getStringExtra(OutgoingCallBroadcaster.EXTRA_ACTUAL_NUMBER_TO_DIAL);
            if (DBG) {
                log("==> got EXTRA_ACTUAL_NUMBER_TO_DIAL; returning '"
                        + toLogSafePhoneNumber(actualNumberToDial) + "'");
            }
            return actualNumberToDial;
        }

        return getNumberFromIntent(PhoneGlobals.getInstance(), intent);
    }

    /**
     * Gets the phone number to be called from an intent.  Requires a Context
     * to access the contacts database, and a Phone to access the voicemail
     * number.
     *
     * <p>If <code>phone</code> is <code>null</code>, the function will return
     * <code>null</code> for <code>voicemail:</code> URIs;
     * if <code>context</code> is <code>null</code>, the function will return
     * <code>null</code> for person/phone URIs.</p>
     *
     * <p>If the intent contains a <code>sip:</code> URI, the returned
     * "number" is actually the SIP address.
     *
     * @param context a context to use (or
     * @param intent the intent
     *
     * @throws VoiceMailNumberMissingException if <code>intent</code> contains
     *         a <code>voicemail:</code> URI, but <code>phone</code> does not
     *         have a voicemail number set.
     *
     * @return the phone number (or SIP address) that would be called by the intent,
     *         or <code>null</code> if the number cannot be found.
     */
    private static String getNumberFromIntent(Context context, Intent intent)
            throws VoiceMailNumberMissingException {
        Uri uri = intent.getData();
        String scheme = uri.getScheme();

        // The sip: scheme is simple: just treat the rest of the URI as a
        // SIP address.
        if (PhoneAccount.SCHEME_SIP.equals(scheme)) {
            return uri.getSchemeSpecificPart();
        }

        // Otherwise, let PhoneNumberUtils.getNumberFromIntent() handle
        // the other cases (i.e. tel: and voicemail: and contact: URIs.)

        final String number = PhoneNumberUtils.getNumberFromIntent(intent, context);

        // Check for a voicemail-dialing request.  If the voicemail number is
        // empty, throw a VoiceMailNumberMissingException.
        if (PhoneAccount.SCHEME_VOICEMAIL.equals(scheme) &&
                (number == null || TextUtils.isEmpty(number)))
            throw new VoiceMailNumberMissingException();

        return number;
    }

    /**
     * Returns the caller-id info corresponding to the specified Connection.
     * (This is just a simple wrapper around CallerInfo.getCallerInfo(): we
     * extract a phone number from the specified Connection, and feed that
     * number into CallerInfo.getCallerInfo().)
     *
     * The returned CallerInfo may be null in certain error cases, like if the
     * specified Connection was null, or if we weren't able to get a valid
     * phone number from the Connection.
     *
     * Finally, if the getCallerInfo() call did succeed, we save the resulting
     * CallerInfo object in the "userData" field of the Connection.
     *
     * NOTE: This API should be avoided, with preference given to the
     * asynchronous startGetCallerInfo API.
     */
    static CallerInfo getCallerInfo(Context context, Connection c) {
        CallerInfo info = null;

        if (c != null) {
            //See if there is a URI attached.  If there is, this means
            //that there is no CallerInfo queried yet, so we'll need to
            //replace the URI with a full CallerInfo object.
            Object userDataObject = c.getUserData();
            if (userDataObject instanceof Uri) {
                info = CallerInfo.getCallerInfo(context, (Uri) userDataObject);
                if (info != null) {
                    c.setUserData(info);
                }
            } else {
                if (userDataObject instanceof CallerInfoToken) {
                    //temporary result, while query is running
                    info = ((CallerInfoToken) userDataObject).currentInfo;
                } else {
                    //final query result
                    info = (CallerInfo) userDataObject;
                }
                if (info == null) {
                    // No URI, or Existing CallerInfo, so we'll have to make do with
                    // querying a new CallerInfo using the connection's phone number.
                    String number = c.getAddress();

                    if (DBG) log("getCallerInfo: number = " + toLogSafePhoneNumber(number));

                    if (!TextUtils.isEmpty(number)) {
                        info = CallerInfo.getCallerInfo(context, number);
                        if (info != null) {
                            c.setUserData(info);
                        }
                    }
                }
            }
        }
        return info;
    }

    /**
     * Class returned by the startGetCallerInfo call to package a temporary
     * CallerInfo Object, to be superceded by the CallerInfo Object passed
     * into the listener when the query with token mAsyncQueryToken is complete.
     */
    public static class CallerInfoToken {
        /**indicates that there will no longer be updates to this request.*/
        public boolean isFinal;

        public CallerInfo currentInfo;
        public CallerInfoAsyncQuery asyncQuery;
    }

    /**
     * Start a CallerInfo Query based on the earliest connection in the call.
     */
    static CallerInfoToken startGetCallerInfo(Context context, Call call,
            CallerInfoAsyncQuery.OnQueryCompleteListener listener, Object cookie) {
        Connection conn = null;
        int phoneType = call.getPhone().getPhoneType();
        if (phoneType == PhoneConstants.PHONE_TYPE_CDMA) {
            conn = call.getLatestConnection();
        } else if ((phoneType == PhoneConstants.PHONE_TYPE_GSM)
                || (phoneType == PhoneConstants.PHONE_TYPE_SIP)
                || (phoneType == PhoneConstants.PHONE_TYPE_IMS)
                || (phoneType == PhoneConstants.PHONE_TYPE_THIRD_PARTY)) {
            conn = call.getEarliestConnection();
        } else {
            throw new IllegalStateException("Unexpected phone type: " + phoneType);
        }

        return startGetCallerInfo(context, conn, listener, cookie);
    }

    static CallerInfoToken startGetCallerInfo(Context context, Connection c,
            CallerInfoAsyncQuery.OnQueryCompleteListener listener, Object cookie) {
        return startGetCallerInfo(context, c, listener, cookie, null);
    }

    /**
     * place a temporary callerinfo object in the hands of the caller and notify
     * caller when the actual query is done.
     */
    static CallerInfoToken startGetCallerInfo(Context context, Connection c,
            CallerInfoAsyncQuery.OnQueryCompleteListener listener, Object cookie,
            RawGatewayInfo info) {
        CallerInfoToken cit;

        if (c == null) {
            //TODO: perhaps throw an exception here.
            cit = new CallerInfoToken();
            cit.asyncQuery = null;
            return cit;
        }

        Object userDataObject = c.getUserData();

        // There are now 3 states for the Connection's userData object:
        //
        //   (1) Uri - query has not been executed yet
        //
        //   (2) CallerInfoToken - query is executing, but has not completed.
        //
        //   (3) CallerInfo - query has executed.
        //
        // In each case we have slightly different behaviour:
        //   1. If the query has not been executed yet (Uri or null), we start
        //      query execution asynchronously, and note it by attaching a
        //      CallerInfoToken as the userData.
        //   2. If the query is executing (CallerInfoToken), we've essentially
        //      reached a state where we've received multiple requests for the
        //      same callerInfo.  That means that once the query is complete,
        //      we'll need to execute the additional listener requested.
        //   3. If the query has already been executed (CallerInfo), we just
        //      return the CallerInfo object as expected.
        //   4. Regarding isFinal - there are cases where the CallerInfo object
        //      will not be attached, like when the number is empty (caller id
        //      blocking).  This flag is used to indicate that the
        //      CallerInfoToken object is going to be permanent since no
        //      query results will be returned.  In the case where a query
        //      has been completed, this flag is used to indicate to the caller
        //      that the data will not be updated since it is valid.
        //
        //      Note: For the case where a number is NOT retrievable, we leave
        //      the CallerInfo as null in the CallerInfoToken.  This is
        //      something of a departure from the original code, since the old
        //      code manufactured a CallerInfo object regardless of the query
        //      outcome.  From now on, we will append an empty CallerInfo
        //      object, to mirror previous behaviour, and to avoid Null Pointer
        //      Exceptions.

        if (userDataObject instanceof Uri) {
            // State (1): query has not been executed yet

            //create a dummy callerinfo, populate with what we know from URI.
            cit = new CallerInfoToken();
            cit.currentInfo = new CallerInfo();
            cit.asyncQuery = CallerInfoAsyncQuery.startQuery(QUERY_TOKEN, context,
                    (Uri) userDataObject, sCallerInfoQueryListener, c);
            cit.asyncQuery.addQueryListener(QUERY_TOKEN, listener, cookie);
            cit.isFinal = false;

            c.setUserData(cit);

            if (DBG) log("startGetCallerInfo: query based on Uri: " + userDataObject);

        } else if (userDataObject == null) {
            // No URI, or Existing CallerInfo, so we'll have to make do with
            // querying a new CallerInfo using the connection's phone number.
            String number = c.getAddress();

            if (info != null && info != CallGatewayManager.EMPTY_INFO) {
                // Gateway number, the connection number is actually the gateway number.
                // need to lookup via dialed number.
                number = info.trueNumber;
            }

            if (DBG) {
                log("PhoneUtils.startGetCallerInfo: new query for phone number...");
                log("- number (address): " + toLogSafePhoneNumber(number));
                log("- c: " + c);
                log("- phone: " + c.getCall().getPhone());
                int phoneType = c.getCall().getPhone().getPhoneType();
                log("- phoneType: " + phoneType);
                switch (phoneType) {
                    case PhoneConstants.PHONE_TYPE_NONE: log("  ==> PHONE_TYPE_NONE"); break;
                    case PhoneConstants.PHONE_TYPE_GSM: log("  ==> PHONE_TYPE_GSM"); break;
                    case PhoneConstants.PHONE_TYPE_IMS: log("  ==> PHONE_TYPE_IMS"); break;
                    case PhoneConstants.PHONE_TYPE_CDMA: log("  ==> PHONE_TYPE_CDMA"); break;
                    case PhoneConstants.PHONE_TYPE_SIP: log("  ==> PHONE_TYPE_SIP"); break;
                    case PhoneConstants.PHONE_TYPE_THIRD_PARTY:
                        log("  ==> PHONE_TYPE_THIRD_PARTY");
                        break;
                    default: log("  ==> Unknown phone type"); break;
                }
            }

            cit = new CallerInfoToken();
            cit.currentInfo = new CallerInfo();

            // Store CNAP information retrieved from the Connection (we want to do this
            // here regardless of whether the number is empty or not).
            cit.currentInfo.cnapName =  c.getCnapName();
            cit.currentInfo.name = cit.currentInfo.cnapName; // This can still get overwritten
                                                             // by ContactInfo later
            cit.currentInfo.numberPresentation = c.getNumberPresentation();
            cit.currentInfo.namePresentation = c.getCnapNamePresentation();

            if (VDBG) {
                log("startGetCallerInfo: number = " + number);
                log("startGetCallerInfo: CNAP Info from FW(1): name="
                    + cit.currentInfo.cnapName
                    + ", Name/Number Pres=" + cit.currentInfo.numberPresentation);
            }

            // handling case where number is null (caller id hidden) as well.
            if (!TextUtils.isEmpty(number)) {
                // Check for special CNAP cases and modify the CallerInfo accordingly
                // to be sure we keep the right information to display/log later
                number = modifyForSpecialCnapCases(context, cit.currentInfo, number,
                        cit.currentInfo.numberPresentation);

                cit.currentInfo.phoneNumber = number;
                // For scenarios where we may receive a valid number from the network but a
                // restricted/unavailable presentation, we do not want to perform a contact query
                // (see note on isFinal above). So we set isFinal to true here as well.
                if (cit.currentInfo.numberPresentation != PhoneConstants.PRESENTATION_ALLOWED) {
                    cit.isFinal = true;
                } else {
                    if (DBG) log("==> Actually starting CallerInfoAsyncQuery.startQuery()...");
                    cit.asyncQuery = CallerInfoAsyncQuery.startQuery(QUERY_TOKEN, context,
                            number, sCallerInfoQueryListener, c);
                    cit.asyncQuery.addQueryListener(QUERY_TOKEN, listener, cookie);
                    cit.isFinal = false;
                }
            } else {
                // This is the case where we are querying on a number that
                // is null or empty, like a caller whose caller id is
                // blocked or empty (CLIR).  The previous behaviour was to
                // throw a null CallerInfo object back to the user, but
                // this departure is somewhat cleaner.
                if (DBG) log("startGetCallerInfo: No query to start, send trivial reply.");
                cit.isFinal = true; // please see note on isFinal, above.
            }

            c.setUserData(cit);

            if (DBG) {
                log("startGetCallerInfo: query based on number: " + toLogSafePhoneNumber(number));
            }

        } else if (userDataObject instanceof CallerInfoToken) {
            // State (2): query is executing, but has not completed.

            // just tack on this listener to the queue.
            cit = (CallerInfoToken) userDataObject;

            // handling case where number is null (caller id hidden) as well.
            if (cit.asyncQuery != null) {
                cit.asyncQuery.addQueryListener(QUERY_TOKEN, listener, cookie);

                if (DBG) log("startGetCallerInfo: query already running, adding listener: " +
                        listener.getClass().toString());
            } else {
                // handling case where number/name gets updated later on by the network
                String updatedNumber = c.getAddress();

                if (info != null) {
                    // Gateway number, the connection number is actually the gateway number.
                    // need to lookup via dialed number.
                    updatedNumber = info.trueNumber;
                }

                if (DBG) {
                    log("startGetCallerInfo: updatedNumber initially = "
                            + toLogSafePhoneNumber(updatedNumber));
                }
                if (!TextUtils.isEmpty(updatedNumber)) {
                    // Store CNAP information retrieved from the Connection
                    cit.currentInfo.cnapName =  c.getCnapName();
                    // This can still get overwritten by ContactInfo
                    cit.currentInfo.name = cit.currentInfo.cnapName;
                    cit.currentInfo.numberPresentation = c.getNumberPresentation();
                    cit.currentInfo.namePresentation = c.getCnapNamePresentation();

                    updatedNumber = modifyForSpecialCnapCases(context, cit.currentInfo,
                            updatedNumber, cit.currentInfo.numberPresentation);

                    cit.currentInfo.phoneNumber = updatedNumber;
                    if (DBG) {
                        log("startGetCallerInfo: updatedNumber="
                                + toLogSafePhoneNumber(updatedNumber));
                    }
                    if (VDBG) {
                        log("startGetCallerInfo: CNAP Info from FW(2): name="
                                + cit.currentInfo.cnapName
                                + ", Name/Number Pres=" + cit.currentInfo.numberPresentation);
                    } else if (DBG) {
                        log("startGetCallerInfo: CNAP Info from FW(2)");
                    }
                    // For scenarios where we may receive a valid number from the network but a
                    // restricted/unavailable presentation, we do not want to perform a contact query
                    // (see note on isFinal above). So we set isFinal to true here as well.
                    if (cit.currentInfo.numberPresentation != PhoneConstants.PRESENTATION_ALLOWED) {
                        cit.isFinal = true;
                    } else {
                        cit.asyncQuery = CallerInfoAsyncQuery.startQuery(QUERY_TOKEN, context,
                                updatedNumber, sCallerInfoQueryListener, c);
                        cit.asyncQuery.addQueryListener(QUERY_TOKEN, listener, cookie);
                        cit.isFinal = false;
                    }
                } else {
                    if (DBG) log("startGetCallerInfo: No query to attach to, send trivial reply.");
                    if (cit.currentInfo == null) {
                        cit.currentInfo = new CallerInfo();
                    }
                    // Store CNAP information retrieved from the Connection
                    cit.currentInfo.cnapName = c.getCnapName();  // This can still get
                                                                 // overwritten by ContactInfo
                    cit.currentInfo.name = cit.currentInfo.cnapName;
                    cit.currentInfo.numberPresentation = c.getNumberPresentation();
                    cit.currentInfo.namePresentation = c.getCnapNamePresentation();

                    if (VDBG) {
                        log("startGetCallerInfo: CNAP Info from FW(3): name="
                                + cit.currentInfo.cnapName
                                + ", Name/Number Pres=" + cit.currentInfo.numberPresentation);
                    } else if (DBG) {
                        log("startGetCallerInfo: CNAP Info from FW(3)");
                    }
                    cit.isFinal = true; // please see note on isFinal, above.
                }
            }
        } else {
            // State (3): query is complete.

            // The connection's userDataObject is a full-fledged
            // CallerInfo instance.  Wrap it in a CallerInfoToken and
            // return it to the user.

            cit = new CallerInfoToken();
            cit.currentInfo = (CallerInfo) userDataObject;
            cit.asyncQuery = null;
            cit.isFinal = true;
            // since the query is already done, call the listener.
            if (DBG) log("startGetCallerInfo: query already done, returning CallerInfo");
            if (DBG) log("==> cit.currentInfo = " + cit.currentInfo);
        }
        return cit;
    }

    /**
     * Static CallerInfoAsyncQuery.OnQueryCompleteListener instance that
     * we use with all our CallerInfoAsyncQuery.startQuery() requests.
     */
    private static final int QUERY_TOKEN = -1;
    static CallerInfoAsyncQuery.OnQueryCompleteListener sCallerInfoQueryListener =
        new CallerInfoAsyncQuery.OnQueryCompleteListener () {
            /**
             * When the query completes, we stash the resulting CallerInfo
             * object away in the Connection's "userData" (where it will
             * later be retrieved by the in-call UI.)
             */
            public void onQueryComplete(int token, Object cookie, CallerInfo ci) {
                if (DBG) log("query complete, updating connection.userdata");
                Connection conn = (Connection) cookie;

                // Added a check if CallerInfo is coming from ContactInfo or from Connection.
                // If no ContactInfo, then we want to use CNAP information coming from network
                if (DBG) log("- onQueryComplete: CallerInfo:" + ci);
                if (ci.contactExists || ci.isEmergencyNumber() || ci.isVoiceMailNumber()) {
                    // If the number presentation has not been set by
                    // the ContactInfo, use the one from the
                    // connection.

                    // TODO: Need a new util method to merge the info
                    // from the Connection in a CallerInfo object.
                    // Here 'ci' is a new CallerInfo instance read
                    // from the DB. It has lost all the connection
                    // info preset before the query (see PhoneUtils
                    // line 1334). We should have a method to merge
                    // back into this new instance the info from the
                    // connection object not set by the DB. If the
                    // Connection already has a CallerInfo instance in
                    // userData, then we could use this instance to
                    // fill 'ci' in. The same routine could be used in
                    // PhoneUtils.
                    if (0 == ci.numberPresentation) {
                        ci.numberPresentation = conn.getNumberPresentation();
                    }
                } else {
                    // No matching contact was found for this number.
                    // Return a new CallerInfo based solely on the CNAP
                    // information from the network.

                    CallerInfo newCi = getCallerInfo(null, conn);

                    // ...but copy over the (few) things we care about
                    // from the original CallerInfo object:
                    if (newCi != null) {
                        newCi.phoneNumber = ci.phoneNumber; // To get formatted phone number
                        newCi.geoDescription = ci.geoDescription; // To get geo description string
                        ci = newCi;
                    }
                }

                if (DBG) log("==> Stashing CallerInfo " + ci + " into the connection...");
                conn.setUserData(ci);
            }
        };


    /**
     * Returns a single "name" for the specified given a CallerInfo object.
     * If the name is null, return defaultString as the default value, usually
     * context.getString(R.string.unknown).
     */
    static String getCompactNameFromCallerInfo(CallerInfo ci, Context context) {
        if (DBG) log("getCompactNameFromCallerInfo: info = " + ci);

        String compactName = null;
        if (ci != null) {
            if (TextUtils.isEmpty(ci.name)) {
                // Perform any modifications for special CNAP cases to
                // the phone number being displayed, if applicable.
                compactName = modifyForSpecialCnapCases(context, ci, ci.phoneNumber,
                                                        ci.numberPresentation);
            } else {
                // Don't call modifyForSpecialCnapCases on regular name. See b/2160795.
                compactName = ci.name;
            }
        }

        if ((compactName == null) || (TextUtils.isEmpty(compactName))) {
            // If we're still null/empty here, then check if we have a presentation
            // string that takes precedence that we could return, otherwise display
            // "unknown" string.
            if (ci != null && ci.numberPresentation == PhoneConstants.PRESENTATION_RESTRICTED) {
                compactName = context.getString(R.string.private_num);
            } else if (ci != null && ci.numberPresentation == PhoneConstants.PRESENTATION_PAYPHONE) {
                compactName = context.getString(R.string.payphone);
            } else {
                compactName = context.getString(R.string.unknown);
            }
        }
        if (VDBG) log("getCompactNameFromCallerInfo: compactName=" + compactName);
        return compactName;
    }

    /**
     * Returns true if the specified Call is a "conference call", meaning
     * that it owns more than one Connection object.  This information is
     * used to trigger certain UI changes that appear when a conference
     * call is active (like displaying the label "Conference call", and
     * enabling the "Manage conference" UI.)
     *
     * Watch out: This method simply checks the number of Connections,
     * *not* their states.  So if a Call has (for example) one ACTIVE
     * connection and one DISCONNECTED connection, this method will return
     * true (which is unintuitive, since the Call isn't *really* a
     * conference call any more.)
     *
     * @return true if the specified call has more than one connection (in any state.)
     */
    static boolean isConferenceCall(Call call) {
        // CDMA phones don't have the same concept of "conference call" as
        // GSM phones do; there's no special "conference call" state of
        // the UI or a "manage conference" function.  (Instead, when
        // you're in a 3-way call, all we can do is display the "generic"
        // state of the UI.)  So as far as the in-call UI is concerned,
        // Conference corresponds to generic display.
        final PhoneGlobals app = PhoneGlobals.getInstance();
        int phoneType = call.getPhone().getPhoneType();
        if (phoneType == PhoneConstants.PHONE_TYPE_CDMA) {
            CdmaPhoneCallState.PhoneCallState state = app.cdmaPhoneCallState.getCurrentCallState();
            if ((state == CdmaPhoneCallState.PhoneCallState.CONF_CALL)
                    || ((state == CdmaPhoneCallState.PhoneCallState.THRWAY_ACTIVE)
                    && !app.cdmaPhoneCallState.IsThreeWayCallOrigStateDialing())) {
                return true;
            }
        } else {
            List<Connection> connections = call.getConnections();
            if (connections != null && connections.size() > 1) {
                return true;
            }
        }
        return false;

        // TODO: We may still want to change the semantics of this method
        // to say that a given call is only really a conference call if
        // the number of ACTIVE connections, not the total number of
        // connections, is greater than one.  (See warning comment in the
        // javadoc above.)
        // Here's an implementation of that:
        //        if (connections == null) {
        //            return false;
        //        }
        //        int numActiveConnections = 0;
        //        for (Connection conn : connections) {
        //            if (DBG) log("  - CONN: " + conn + ", state = " + conn.getState());
        //            if (conn.getState() == Call.State.ACTIVE) numActiveConnections++;
        //            if (numActiveConnections > 1) {
        //                return true;
        //            }
        //        }
        //        return false;
    }

    /**
     * Launch the Dialer to start a new call.
     * This is just a wrapper around the ACTION_DIAL intent.
     */
    /* package */ static boolean startNewCall(final CallManager cm) {
        final PhoneGlobals app = PhoneGlobals.getInstance();

        // Sanity-check that this is OK given the current state of the phone.
        if (!okToAddCall(cm)) {
            Log.w(LOG_TAG, "startNewCall: can't add a new call in the current state");
            dumpCallManager();
            return false;
        }

        Intent intent = new Intent(Intent.ACTION_DIAL);
        intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);

        // when we request the dialer come up, we also want to inform
        // it that we're going through the "add call" option from the
        // InCallScreen / PhoneUtils.
        intent.putExtra(ADD_CALL_MODE_KEY, true);
        try {
            app.startActivity(intent);
        } catch (ActivityNotFoundException e) {
            // This is rather rare but possible.
            // Note: this method is used even when the phone is encrypted. At that moment
            // the system may not find any Activity which can accept this Intent.
            Log.e(LOG_TAG, "Activity for adding calls isn't found.");
            return false;
        }

        return true;
    }

    /**
     * Turns on/off speaker.
     *
     * @param context Context
     * @param flag True when speaker should be on. False otherwise.
     * @param store True when the settings should be stored in the device.
     */
    /* package */ static void turnOnSpeaker(Context context, boolean flag, boolean store) {
        if (DBG) log("turnOnSpeaker(flag=" + flag + ", store=" + store + ")...");
        final PhoneGlobals app = PhoneGlobals.getInstance();

        AudioManager audioManager = (AudioManager) context.getSystemService(Context.AUDIO_SERVICE);
        audioManager.setSpeakerphoneOn(flag);

        // record the speaker-enable value
        if (store) {
            sIsSpeakerEnabled = flag;
        }

        // We also need to make a fresh call to PhoneApp.updateWakeState()
        // any time the speaker state changes, since the screen timeout is
        // sometimes different depending on whether or not the speaker is
        // in use.
        app.updateWakeState();

        app.mCM.setEchoSuppressionEnabled();
    }

    /**
     * Restore the speaker mode, called after a wired headset disconnect
     * event.
     */
    static void restoreSpeakerMode(Context context) {
        if (DBG) log("restoreSpeakerMode, restoring to: " + sIsSpeakerEnabled);

        // change the mode if needed.
        if (isSpeakerOn(context) != sIsSpeakerEnabled) {
            turnOnSpeaker(context, sIsSpeakerEnabled, false);
        }
    }

    static boolean isSpeakerOn(Context context) {
        AudioManager audioManager = (AudioManager) context.getSystemService(Context.AUDIO_SERVICE);
        return audioManager.isSpeakerphoneOn();
    }


    static void turnOnNoiseSuppression(Context context, boolean flag, boolean store) {
        if (DBG) log("turnOnNoiseSuppression: " + flag);
        AudioManager audioManager = (AudioManager) context.getSystemService(Context.AUDIO_SERVICE);

        PersistableBundle b = PhoneGlobals.getInstance().getCarrierConfig();
        if (!b.getBoolean(CarrierConfigManager.KEY_HAS_IN_CALL_NOISE_SUPPRESSION_BOOL)) {
            return;
        }

        if (flag) {
            audioManager.setParameters("noise_suppression=auto");
        } else {
            audioManager.setParameters("noise_suppression=off");
        }

        // record the speaker-enable value
        if (store) {
            sIsNoiseSuppressionEnabled = flag;
        }

        // TODO: implement and manage ICON

    }

    static void restoreNoiseSuppression(Context context) {
        if (DBG) log("restoreNoiseSuppression, restoring to: " + sIsNoiseSuppressionEnabled);

        PersistableBundle b = PhoneGlobals.getInstance().getCarrierConfig();
        if (!b.getBoolean(CarrierConfigManager.KEY_HAS_IN_CALL_NOISE_SUPPRESSION_BOOL)) {
            return;
        }

        // change the mode if needed.
        if (isNoiseSuppressionOn(context) != sIsNoiseSuppressionEnabled) {
            turnOnNoiseSuppression(context, sIsNoiseSuppressionEnabled, false);
        }
    }

    static boolean isNoiseSuppressionOn(Context context) {

        PersistableBundle b = PhoneGlobals.getInstance().getCarrierConfig();
        if (!b.getBoolean(CarrierConfigManager.KEY_HAS_IN_CALL_NOISE_SUPPRESSION_BOOL)) {
            return false;
        }

        AudioManager audioManager = (AudioManager) context.getSystemService(Context.AUDIO_SERVICE);
        String noiseSuppression = audioManager.getParameters("noise_suppression");
        if (DBG) log("isNoiseSuppressionOn: " + noiseSuppression);
        if (noiseSuppression.contains("off")) {
            return false;
        } else {
            return true;
        }
    }

    static boolean isInEmergencyCall(CallManager cm) {
        Call fgCall = cm.getActiveFgCall();
        // isIdle includes checks for the DISCONNECTING/DISCONNECTED state.
        if(!fgCall.isIdle()) {
            for (Connection cn : fgCall.getConnections()) {
                if (PhoneNumberUtils.isLocalEmergencyNumber(PhoneGlobals.getInstance(),
                        cn.getAddress())) {
                    return true;
                }
            }
        }
        return false;
    }

    /**
     * Get the mute state of foreground phone, which has the current
     * foreground call
     */
    static boolean getMute() {
        return false;
    }

    /* package */ static void setAudioMode() {
    }

    /**
     * Sets the audio mode per current phone state.
     */
    /* package */ static void setAudioMode(CallManager cm) {
    }

    /**
     * Look for ANY connections on the phone that qualify as being
     * disconnected.
     *
     * @return true if we find a connection that is disconnected over
     * all the phone's call objects.
     */
    /* package */ static boolean hasDisconnectedConnections(Phone phone) {
        return hasDisconnectedConnections(phone.getForegroundCall()) ||
                hasDisconnectedConnections(phone.getBackgroundCall()) ||
                hasDisconnectedConnections(phone.getRingingCall());
    }

    /**
     * Iterate over all connections in a call to see if there are any
     * that are not alive (disconnected or idle).
     *
     * @return true if we find a connection that is disconnected, and
     * pending removal via
     * {@link com.android.internal.telephony.Call#clearDisconnected()}.
     */
    private static final boolean hasDisconnectedConnections(Call call) {
        // look through all connections for non-active ones.
        for (Connection c : call.getConnections()) {
            if (!c.isAlive()) {
                return true;
            }
        }
        return false;
    }

    //
    // Misc UI policy helper functions
    //

    /**
     * @return true if we're allowed to hold calls, given the current
     * state of the Phone.
     */
    /* package */ static boolean okToHoldCall(CallManager cm) {
        final Call fgCall = cm.getActiveFgCall();
        final boolean hasHoldingCall = cm.hasActiveBgCall();
        final Call.State fgCallState = fgCall.getState();

        // The "Hold" control is disabled entirely if there's
        // no way to either hold or unhold in the current state.
        final boolean okToHold = (fgCallState == Call.State.ACTIVE) && !hasHoldingCall;
        final boolean okToUnhold = cm.hasActiveBgCall() && (fgCallState == Call.State.IDLE);
        final boolean canHold = okToHold || okToUnhold;

        return canHold;
    }

    /**
     * @return true if we support holding calls, given the current
     * state of the Phone.
     */
    /* package */ static boolean okToSupportHold(CallManager cm) {
        boolean supportsHold = false;

        final Call fgCall = cm.getActiveFgCall();
        final boolean hasHoldingCall = cm.hasActiveBgCall();
        final Call.State fgCallState = fgCall.getState();

        if (TelephonyCapabilities.supportsHoldAndUnhold(fgCall.getPhone())) {
            // This phone has the concept of explicit "Hold" and "Unhold" actions.
            supportsHold = true;
        } else if (hasHoldingCall && (fgCallState == Call.State.IDLE)) {
            // Even when foreground phone device doesn't support hold/unhold, phone devices
            // for background holding calls may do.
            final Call bgCall = cm.getFirstActiveBgCall();
            if (bgCall != null &&
                    TelephonyCapabilities.supportsHoldAndUnhold(bgCall.getPhone())) {
                supportsHold = true;
            }
        }
        return supportsHold;
    }

    /**
     * @return true if we're allowed to swap calls, given the current
     * state of the Phone.
     */
    /* package */ static boolean okToSwapCalls(CallManager cm) {
        int phoneType = cm.getDefaultPhone().getPhoneType();
        if (phoneType == PhoneConstants.PHONE_TYPE_CDMA) {
            // CDMA: "Swap" is enabled only when the phone reaches a *generic*.
            // state by either accepting a Call Waiting or by merging two calls
            PhoneGlobals app = PhoneGlobals.getInstance();
            return (app.cdmaPhoneCallState.getCurrentCallState()
                    == CdmaPhoneCallState.PhoneCallState.CONF_CALL);
        } else if ((phoneType == PhoneConstants.PHONE_TYPE_GSM)
                || (phoneType == PhoneConstants.PHONE_TYPE_SIP)
                || (phoneType == PhoneConstants.PHONE_TYPE_IMS)
                || (phoneType == PhoneConstants.PHONE_TYPE_THIRD_PARTY)) {
            // GSM: "Swap" is available if both lines are in use and there's no
            // incoming call.  (Actually we need to verify that the active
            // call really is in the ACTIVE state and the holding call really
            // is in the HOLDING state, since you *can't* actually swap calls
            // when the foreground call is DIALING or ALERTING.)
            return !cm.hasActiveRingingCall()
                    && (cm.getActiveFgCall().getState() == Call.State.ACTIVE)
                    && (cm.getFirstActiveBgCall().getState() == Call.State.HOLDING);
        } else {
            throw new IllegalStateException("Unexpected phone type: " + phoneType);
        }
    }

    /**
     * @return true if we're allowed to merge calls, given the current
     * state of the Phone.
     */
    /* package */ static boolean okToMergeCalls(CallManager cm) {
        int phoneType = cm.getFgPhone().getPhoneType();
        if (phoneType == PhoneConstants.PHONE_TYPE_CDMA) {
            // CDMA: "Merge" is enabled only when the user is in a 3Way call.
            PhoneGlobals app = PhoneGlobals.getInstance();
            return ((app.cdmaPhoneCallState.getCurrentCallState()
                    == CdmaPhoneCallState.PhoneCallState.THRWAY_ACTIVE)
                    && !app.cdmaPhoneCallState.IsThreeWayCallOrigStateDialing());
        } else {
            // GSM: "Merge" is available if both lines are in use and there's no
            // incoming call, *and* the current conference isn't already
            // "full".
            // TODO: shall move all okToMerge logic to CallManager
            return !cm.hasActiveRingingCall() && cm.hasActiveFgCall()
                    && cm.hasActiveBgCall()
                    && cm.canConference(cm.getFirstActiveBgCall());
        }
    }

    /**
     * @return true if the UI should let you add a new call, given the current
     * state of the Phone.
     */
    /* package */ static boolean okToAddCall(CallManager cm) {
        Phone phone = cm.getActiveFgCall().getPhone();

        // "Add call" is never allowed in emergency callback mode (ECM).
        if (isPhoneInEcm(phone)) {
            return false;
        }

        int phoneType = phone.getPhoneType();
        final Call.State fgCallState = cm.getActiveFgCall().getState();
        if (phoneType == PhoneConstants.PHONE_TYPE_CDMA) {
           // CDMA: "Add call" button is only enabled when:
           // - ForegroundCall is in ACTIVE state
           // - After 30 seconds of user Ignoring/Missing a Call Waiting call.
            PhoneGlobals app = PhoneGlobals.getInstance();
            return ((fgCallState == Call.State.ACTIVE)
                    && (app.cdmaPhoneCallState.getAddCallMenuStateAfterCallWaiting()));
        } else if ((phoneType == PhoneConstants.PHONE_TYPE_GSM)
                || (phoneType == PhoneConstants.PHONE_TYPE_SIP)
                || (phoneType == PhoneConstants.PHONE_TYPE_IMS)
                || (phoneType == PhoneConstants.PHONE_TYPE_THIRD_PARTY)) {
            // GSM: "Add call" is available only if ALL of the following are true:
            // - There's no incoming ringing call
            // - There's < 2 lines in use
            // - The foreground call is ACTIVE or IDLE or DISCONNECTED.
            //   (We mainly need to make sure it *isn't* DIALING or ALERTING.)
            final boolean hasRingingCall = cm.hasActiveRingingCall();
            final boolean hasActiveCall = cm.hasActiveFgCall();
            final boolean hasHoldingCall = cm.hasActiveBgCall();
            final boolean allLinesTaken = hasActiveCall && hasHoldingCall;

            return !hasRingingCall
                    && !allLinesTaken
                    && ((fgCallState == Call.State.ACTIVE)
                        || (fgCallState == Call.State.IDLE)
                        || (fgCallState == Call.State.DISCONNECTED));
        } else {
            throw new IllegalStateException("Unexpected phone type: " + phoneType);
        }
    }

    /**
     * Based on the input CNAP number string,
     * @return _RESTRICTED or _UNKNOWN for all the special CNAP strings.
     * Otherwise, return CNAP_SPECIAL_CASE_NO.
     */
    private static int checkCnapSpecialCases(String n) {
        if (n.equals("PRIVATE") ||
                n.equals("P") ||
                n.equals("RES")) {
            if (DBG) log("checkCnapSpecialCases, PRIVATE string: " + n);
            return PhoneConstants.PRESENTATION_RESTRICTED;
        } else if (n.equals("UNAVAILABLE") ||
                n.equals("UNKNOWN") ||
                n.equals("UNA") ||
                n.equals("U")) {
            if (DBG) log("checkCnapSpecialCases, UNKNOWN string: " + n);
            return PhoneConstants.PRESENTATION_UNKNOWN;
        } else {
            if (DBG) log("checkCnapSpecialCases, normal str. number: " + n);
            return CNAP_SPECIAL_CASE_NO;
        }
    }

    /**
     * Handles certain "corner cases" for CNAP. When we receive weird phone numbers
     * from the network to indicate different number presentations, convert them to
     * expected number and presentation values within the CallerInfo object.
     * @param number number we use to verify if we are in a corner case
     * @param presentation presentation value used to verify if we are in a corner case
     * @return the new String that should be used for the phone number
     */
    /* package */ static String modifyForSpecialCnapCases(Context context, CallerInfo ci,
            String number, int presentation) {
        // Obviously we return number if ci == null, but still return number if
        // number == null, because in these cases the correct string will still be
        // displayed/logged after this function returns based on the presentation value.
        if (ci == null || number == null) return number;

        if (DBG) {
            log("modifyForSpecialCnapCases: initially, number="
                    + toLogSafePhoneNumber(number)
                    + ", presentation=" + presentation + " ci " + ci);
        }

        // "ABSENT NUMBER" is a possible value we could get from the network as the
        // phone number, so if this happens, change it to "Unknown" in the CallerInfo
        // and fix the presentation to be the same.
        final String[] absentNumberValues =
                context.getResources().getStringArray(R.array.absent_num);
        if (Arrays.asList(absentNumberValues).contains(number)
                && presentation == PhoneConstants.PRESENTATION_ALLOWED) {
            number = context.getString(R.string.unknown);
            ci.numberPresentation = PhoneConstants.PRESENTATION_UNKNOWN;
        }

        // Check for other special "corner cases" for CNAP and fix them similarly. Corner
        // cases only apply if we received an allowed presentation from the network, so check
        // if we think we have an allowed presentation, or if the CallerInfo presentation doesn't
        // match the presentation passed in for verification (meaning we changed it previously
        // because it's a corner case and we're being called from a different entry point).
        if (ci.numberPresentation == PhoneConstants.PRESENTATION_ALLOWED
                || (ci.numberPresentation != presentation
                        && presentation == PhoneConstants.PRESENTATION_ALLOWED)) {
            int cnapSpecialCase = checkCnapSpecialCases(number);
            if (cnapSpecialCase != CNAP_SPECIAL_CASE_NO) {
                // For all special strings, change number & numberPresentation.
                if (cnapSpecialCase == PhoneConstants.PRESENTATION_RESTRICTED) {
                    number = context.getString(R.string.private_num);
                } else if (cnapSpecialCase == PhoneConstants.PRESENTATION_UNKNOWN) {
                    number = context.getString(R.string.unknown);
                }
                if (DBG) {
                    log("SpecialCnap: number=" + toLogSafePhoneNumber(number)
                            + "; presentation now=" + cnapSpecialCase);
                }
                ci.numberPresentation = cnapSpecialCase;
            }
        }
        if (DBG) {
            log("modifyForSpecialCnapCases: returning number string="
                    + toLogSafePhoneNumber(number));
        }
        return number;
    }

    //
    // Support for 3rd party phone service providers.
    //

    /**
     * Check if a phone number can be route through a 3rd party
     * gateway. The number must be a global phone number in numerical
     * form (1-800-666-SEXY won't work).
     *
     * MMI codes and the like cannot be used as a dial number for the
     * gateway either.
     *
     * @param number To be dialed via a 3rd party gateway.
     * @return true If the number can be routed through the 3rd party network.
     */
    private static boolean isRoutableViaGateway(String number) {
        if (TextUtils.isEmpty(number)) {
            return false;
        }
        number = PhoneNumberUtils.stripSeparators(number);
        if (!number.equals(PhoneNumberUtils.convertKeypadLettersToDigits(number))) {
            return false;
        }
        number = PhoneNumberUtils.extractNetworkPortion(number);
        return PhoneNumberUtils.isGlobalPhoneNumber(number);
    }

    /**
     * Returns whether the phone is in ECM ("Emergency Callback Mode") or not.
     */
    /* package */ static boolean isPhoneInEcm(Phone phone) {
        if ((phone != null) && TelephonyCapabilities.supportsEcm(phone)) {
            return phone.isInEcm();
        }
        return false;
    }

    /**
     * Returns the most appropriate Phone object to handle a call
     * to the specified number.
     *
     * @param cm the CallManager.
     * @param scheme the scheme from the data URI that the number originally came from.
     * @param number the phone number, or SIP address.
     */
    public static Phone pickPhoneBasedOnNumber(CallManager cm, String scheme, String number,
            String primarySipUri, ComponentName thirdPartyCallComponent) {
        if (DBG) {
            log("pickPhoneBasedOnNumber: scheme " + scheme
                    + ", number " + toLogSafePhoneNumber(number)
                    + ", sipUri "
                    + (primarySipUri != null ? Uri.parse(primarySipUri).toSafeString() : "null")
                    + ", thirdPartyCallComponent: " + thirdPartyCallComponent);
        }

        if (primarySipUri != null) {
            Phone phone = getSipPhoneFromUri(cm, primarySipUri);
            if (phone != null) return phone;
        }

        return cm.getDefaultPhone();
    }

    public static Phone getSipPhoneFromUri(CallManager cm, String target) {
        for (Phone phone : cm.getAllPhones()) {
            if (phone.getPhoneType() == PhoneConstants.PHONE_TYPE_SIP) {
                String sipUri = ((SipPhone) phone).getSipUri();
                if (target.equals(sipUri)) {
                    if (DBG) log("- pickPhoneBasedOnNumber:" +
                            "found SipPhone! obj = " + phone + ", "
                            + phone.getClass());
                    return phone;
                }
            }
        }
        return null;
    }

    /**
     * Returns true when the given call is in INCOMING state and there's no foreground phone call,
     * meaning the call is the first real incoming call the phone is having.
     */
    public static boolean isRealIncomingCall(Call.State state) {
        return (state == Call.State.INCOMING && !PhoneGlobals.getInstance().mCM.hasActiveFgCall());
    }

    public static String getPresentationString(Context context, int presentation) {
        String name = context.getString(R.string.unknown);
        if (presentation == PhoneConstants.PRESENTATION_RESTRICTED) {
            name = context.getString(R.string.private_num);
        } else if (presentation == PhoneConstants.PRESENTATION_PAYPHONE) {
            name = context.getString(R.string.payphone);
        }
        return name;
    }

    public static void sendViewNotificationAsync(Context context, Uri contactUri) {
        if (DBG) Log.d(LOG_TAG, "Send view notification to Contacts (uri: " + contactUri + ")");
        Intent intent = new Intent("com.android.contacts.VIEW_NOTIFICATION", contactUri);
        intent.setClassName("com.android.contacts",
                "com.android.contacts.ViewNotificationService");
        context.startService(intent);
    }

    //
    // General phone and call state debugging/testing code
    //

    /* package */ static void dumpCallState(Phone phone) {
        PhoneGlobals app = PhoneGlobals.getInstance();
        Log.d(LOG_TAG, "dumpCallState():");
        Log.d(LOG_TAG, "- Phone: " + phone + ", name = " + phone.getPhoneName()
              + ", state = " + phone.getState());

        StringBuilder b = new StringBuilder(128);

        Call call = phone.getForegroundCall();
        b.setLength(0);
        b.append("  - FG call: ").append(call.getState());
        b.append(" isAlive ").append(call.getState().isAlive());
        b.append(" isRinging ").append(call.getState().isRinging());
        b.append(" isDialing ").append(call.getState().isDialing());
        b.append(" isIdle ").append(call.isIdle());
        b.append(" hasConnections ").append(call.hasConnections());
        Log.d(LOG_TAG, b.toString());

        call = phone.getBackgroundCall();
        b.setLength(0);
        b.append("  - BG call: ").append(call.getState());
        b.append(" isAlive ").append(call.getState().isAlive());
        b.append(" isRinging ").append(call.getState().isRinging());
        b.append(" isDialing ").append(call.getState().isDialing());
        b.append(" isIdle ").append(call.isIdle());
        b.append(" hasConnections ").append(call.hasConnections());
        Log.d(LOG_TAG, b.toString());

        call = phone.getRingingCall();
        b.setLength(0);
        b.append("  - RINGING call: ").append(call.getState());
        b.append(" isAlive ").append(call.getState().isAlive());
        b.append(" isRinging ").append(call.getState().isRinging());
        b.append(" isDialing ").append(call.getState().isDialing());
        b.append(" isIdle ").append(call.isIdle());
        b.append(" hasConnections ").append(call.hasConnections());
        Log.d(LOG_TAG, b.toString());


        final boolean hasRingingCall = !phone.getRingingCall().isIdle();
        final boolean hasActiveCall = !phone.getForegroundCall().isIdle();
        final boolean hasHoldingCall = !phone.getBackgroundCall().isIdle();
        final boolean allLinesTaken = hasActiveCall && hasHoldingCall;
        b.setLength(0);
        b.append("  - hasRingingCall ").append(hasRingingCall);
        b.append(" hasActiveCall ").append(hasActiveCall);
        b.append(" hasHoldingCall ").append(hasHoldingCall);
        b.append(" allLinesTaken ").append(allLinesTaken);
        Log.d(LOG_TAG, b.toString());

        // On CDMA phones, dump out the CdmaPhoneCallState too:
        if (phone.getPhoneType() == PhoneConstants.PHONE_TYPE_CDMA) {
            if (app.cdmaPhoneCallState != null) {
                Log.d(LOG_TAG, "  - CDMA call state: "
                      + app.cdmaPhoneCallState.getCurrentCallState());
            } else {
                Log.d(LOG_TAG, "  - CDMA device, but null cdmaPhoneCallState!");
            }
        }
    }

    private static void log(String msg) {
        Log.d(LOG_TAG, msg);
    }

    static void dumpCallManager() {
        Call call;
        CallManager cm = PhoneGlobals.getInstance().mCM;
        StringBuilder b = new StringBuilder(128);



        Log.d(LOG_TAG, "############### dumpCallManager() ##############");
        // TODO: Don't log "cm" itself, since CallManager.toString()
        // already spews out almost all this same information.
        // We should fix CallManager.toString() to be more minimal, and
        // use an explicit dumpState() method for the verbose dump.
        // Log.d(LOG_TAG, "CallManager: " + cm
        //         + ", state = " + cm.getState());
        Log.d(LOG_TAG, "CallManager: state = " + cm.getState());
        b.setLength(0);
        call = cm.getActiveFgCall();
        b.append(" - FG call: ").append(cm.hasActiveFgCall()? "YES ": "NO ");
        b.append(call);
        b.append( "  State: ").append(cm.getActiveFgCallState());
        b.append( "  Conn: ").append(cm.getFgCallConnections());
        Log.d(LOG_TAG, b.toString());
        b.setLength(0);
        call = cm.getFirstActiveBgCall();
        b.append(" - BG call: ").append(cm.hasActiveBgCall()? "YES ": "NO ");
        b.append(call);
        b.append( "  State: ").append(cm.getFirstActiveBgCall().getState());
        b.append( "  Conn: ").append(cm.getBgCallConnections());
        Log.d(LOG_TAG, b.toString());
        b.setLength(0);
        call = cm.getFirstActiveRingingCall();
        b.append(" - RINGING call: ").append(cm.hasActiveRingingCall()? "YES ": "NO ");
        b.append(call);
        b.append( "  State: ").append(cm.getFirstActiveRingingCall().getState());
        Log.d(LOG_TAG, b.toString());



        for (Phone phone : CallManager.getInstance().getAllPhones()) {
            if (phone != null) {
                Log.d(LOG_TAG, "Phone: " + phone + ", name = " + phone.getPhoneName()
                        + ", state = " + phone.getState());
                b.setLength(0);
                call = phone.getForegroundCall();
                b.append(" - FG call: ").append(call);
                b.append( "  State: ").append(call.getState());
                b.append( "  Conn: ").append(call.hasConnections());
                Log.d(LOG_TAG, b.toString());
                b.setLength(0);
                call = phone.getBackgroundCall();
                b.append(" - BG call: ").append(call);
                b.append( "  State: ").append(call.getState());
                b.append( "  Conn: ").append(call.hasConnections());
                Log.d(LOG_TAG, b.toString());b.setLength(0);
                call = phone.getRingingCall();
                b.append(" - RINGING call: ").append(call);
                b.append( "  State: ").append(call.getState());
                b.append( "  Conn: ").append(call.hasConnections());
                Log.d(LOG_TAG, b.toString());
            }
        }

        Log.d(LOG_TAG, "############## END dumpCallManager() ###############");
    }

    /**
     * @return if the context is in landscape orientation.
     */
    public static boolean isLandscape(Context context) {
        return context.getResources().getConfiguration().orientation
                == Configuration.ORIENTATION_LANDSCAPE;
    }

    public static PhoneAccountHandle makePstnPhoneAccountHandle(String id) {
        return makePstnPhoneAccountHandleWithPrefix(id, "", false);
    }

    public static PhoneAccountHandle makePstnPhoneAccountHandle(int phoneId) {
        return makePstnPhoneAccountHandle(PhoneFactory.getPhone(phoneId));
    }

    public static PhoneAccountHandle makePstnPhoneAccountHandle(Phone phone) {
        return makePstnPhoneAccountHandleWithPrefix(phone, "", false);
    }

    public static PhoneAccountHandle makePstnPhoneAccountHandleWithPrefix(
            Phone phone, String prefix, boolean isEmergency) {
        // TODO: Should use some sort of special hidden flag to decorate this account as
        // an emergency-only account
        String id = isEmergency ? EMERGENCY_ACCOUNT_HANDLE_ID : prefix +
                String.valueOf(phone.getFullIccSerialNumber());
        return makePstnPhoneAccountHandleWithPrefix(id, prefix, isEmergency);
    }

    public static PhoneAccountHandle makePstnPhoneAccountHandleWithPrefix(
            String id, String prefix, boolean isEmergency) {
        ComponentName pstnConnectionServiceName = getPstnConnectionServiceName();
        return new PhoneAccountHandle(pstnConnectionServiceName, id);
    }

    public static int getSubIdForPhoneAccount(PhoneAccount phoneAccount) {
        if (phoneAccount != null
                && phoneAccount.hasCapabilities(PhoneAccount.CAPABILITY_SIM_SUBSCRIPTION)) {
            return getSubIdForPhoneAccountHandle(phoneAccount.getAccountHandle());
        }
        return SubscriptionManager.INVALID_SUBSCRIPTION_ID;
    }

    public static int getSubIdForPhoneAccountHandle(PhoneAccountHandle handle) {
        Phone phone = getPhoneForPhoneAccountHandle(handle);
        if (phone != null) {
            return phone.getSubId();
        }
        return SubscriptionManager.INVALID_SUBSCRIPTION_ID;
    }

    public static Phone getPhoneForPhoneAccountHandle(PhoneAccountHandle handle) {
        if (handle != null && handle.getComponentName().equals(getPstnConnectionServiceName())) {
            return getPhoneFromIccId(handle.getId());
        }
        return null;
    }


    /**
     * Determine if a given phone account corresponds to an active SIM
     *
     * @param sm An instance of the subscription manager so it is not recreated for each calling of
     * this method.
     * @param handle The handle for the phone account to check
     * @return {@code true} If there is an active SIM for this phone account,
     * {@code false} otherwise.
     */
    public static boolean isPhoneAccountActive(SubscriptionManager sm, PhoneAccountHandle handle) {
        return sm.getActiveSubscriptionInfoForIccIndex(handle.getId()) != null;
    }

    private static ComponentName getPstnConnectionServiceName() {
        return PSTN_CONNECTION_SERVICE_COMPONENT;
    }

    private static Phone getPhoneFromIccId(String iccId) {
        if (!TextUtils.isEmpty(iccId)) {
            for (Phone phone : PhoneFactory.getPhones()) {
                String phoneIccId = phone.getFullIccSerialNumber();
                if (iccId.equals(phoneIccId)) {
                    return phone;
                }
            }
        }
        return null;
    }

    /**
     * Register ICC status for all phones.
     */
    static final void registerIccStatus(Handler handler, int event) {
        for (Phone phone : PhoneFactory.getPhones()) {
            IccCard sim = phone.getIccCard();
            if (sim != null) {
                if (VDBG) Log.v(LOG_TAG, "register for ICC status, phone " + phone.getPhoneId());
                sim.registerForNetworkLocked(handler, event, phone);
            }
        }
    }

    /**
     * Set the radio power on/off state for all phones.
     *
     * @param enabled true means on, false means off.
     */
    static final void setRadioPower(boolean enabled) {
        for (Phone phone : PhoneFactory.getPhones()) {
            phone.setRadioPower(enabled);
        }
    }
}