/*
 * Copyright (C) 2014 MediaTek Inc.
 *
 * 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.internal.telephony.dataconnection;

import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.os.Handler;
import android.os.Message;
import android.os.AsyncResult;
import android.os.SystemProperties;
import android.telephony.ServiceState;
import android.telephony.TelephonyManager;
import android.telephony.SubscriptionManager;

import com.android.internal.telephony.IccCardConstants;
import com.android.internal.telephony.Phone;
import com.android.internal.telephony.PhoneConstants;
import com.android.internal.telephony.PhoneBase;
import com.android.internal.telephony.PhoneProxy;
import com.android.internal.telephony.TelephonyIntents;
import com.android.internal.util.AsyncChannel;
import com.android.internal.telephony.PhoneFactory;
import com.android.internal.telephony.TelephonyProperties;
import com.android.internal.telephony.DefaultPhoneNotifier;
import com.android.internal.telephony.SubscriptionController;

import android.util.Log;
import java.util.HashSet;
import java.util.Iterator;
import android.os.Registrant;
import android.os.RegistrantList;
import android.telephony.Rlog;

public class DctController extends Handler {
    private static final String LOG_TAG = "DctController";
    private static final boolean DBG = true;

    private static final int EVENT_PHONE1_DETACH = 1;
    private static final int EVENT_PHONE2_DETACH = 2;
    private static final int EVENT_PHONE3_DETACH = 3;
    private static final int EVENT_PHONE4_DETACH = 4;
    private static final int EVENT_PHONE1_RADIO_OFF = 5;
    private static final int EVENT_PHONE2_RADIO_OFF = 6;
    private static final int EVENT_PHONE3_RADIO_OFF = 7;
    private static final int EVENT_PHONE4_RADIO_OFF = 8;

    private static final int PHONE_NONE = -1;

    private static DctController sDctController;

    private static final int EVENT_ALL_DATA_DISCONNECTED = 1;
    private static final int EVENT_SET_DATA_ALLOW_DONE = 2;

    private RegistrantList mNotifyDataSwitchInfo = new RegistrantList();
    private SubscriptionController mSubController = SubscriptionController.getInstance();

    private Phone mActivePhone;
    private int mPhoneNum;
    private boolean[] mServicePowerOffFlag;
    private PhoneProxy[] mPhones;
    private DcSwitchState[] mDcSwitchState;
    private DcSwitchAsyncChannel[] mDcSwitchAsyncChannel;
    private Handler[] mDcSwitchStateHandler;

    private HashSet<String> mApnTypes = new HashSet<String>();

    private BroadcastReceiver mDataStateReceiver;
    private Context mContext;

    private int mCurrentDataPhone = PHONE_NONE;
    private int mRequestedDataPhone = PHONE_NONE;

    private Handler mRspHander = new Handler() {
        public void handleMessage(Message msg){
            AsyncResult ar;
            switch(msg.what) {
                case EVENT_PHONE1_DETACH:
                case EVENT_PHONE2_DETACH:
                case EVENT_PHONE3_DETACH:
                case EVENT_PHONE4_DETACH:
                    logd("EVENT_PHONE" + msg.what +
                            "_DETACH: mRequestedDataPhone=" + mRequestedDataPhone);
                    mCurrentDataPhone = PHONE_NONE;
                    if (mRequestedDataPhone != PHONE_NONE) {
                        mCurrentDataPhone = mRequestedDataPhone;
                        mRequestedDataPhone = PHONE_NONE;

                        Iterator<String> itrType = mApnTypes.iterator();
                        while (itrType.hasNext()) {
                            mDcSwitchAsyncChannel[mCurrentDataPhone].connectSync(itrType.next());
                        }
                        mApnTypes.clear();
                    }
                break;

                case EVENT_PHONE1_RADIO_OFF:
                case EVENT_PHONE2_RADIO_OFF:
                case EVENT_PHONE3_RADIO_OFF:
                case EVENT_PHONE4_RADIO_OFF:
                    logd("EVENT_PHONE" + (msg.what - EVENT_PHONE1_RADIO_OFF + 1) + "_RADIO_OFF.");
                    mServicePowerOffFlag[msg.what - EVENT_PHONE1_RADIO_OFF] = true;
                break;

                default:
                break;
            }
        }
    };

    private DefaultPhoneNotifier.IDataStateChangedCallback mDataStateChangedCallback =
            new DefaultPhoneNotifier.IDataStateChangedCallback() {
        public void onDataStateChanged(long subId, String state, String reason,
                String apnName, String apnType, boolean unavailable) {
            logd("[DataStateChanged]:" + "state=" + state + ",reason=" + reason
                      + ",apnName=" + apnName + ",apnType=" + apnType + ",from subId=" + subId);
            int phoneId = SubscriptionManager.getPhoneId(subId);
            mDcSwitchState[phoneId].notifyDataConnection(phoneId, state, reason,
                    apnName, apnType, unavailable);
        }
    };

    private class DataStateReceiver extends BroadcastReceiver {
        public void onReceive(Context context, Intent intent) {
            synchronized(this) {
                if (intent.getAction().equals(TelephonyIntents.ACTION_SERVICE_STATE_CHANGED)) {
                    ServiceState ss = ServiceState.newFromBundle(intent.getExtras());

                    long subId = intent.getLongExtra(PhoneConstants.SUBSCRIPTION_KEY, PhoneConstants.SUB1);
                    int phoneId = SubscriptionManager.getPhoneId(subId);
                    logd("DataStateReceiver: phoneId= " + phoneId);

                    // for the case of network out of service when bootup (ignore dummy values too)
                    if (!SubscriptionManager.isValidSubId(subId) || (subId < 0)) {
                        // FIXME: Maybe add SM.isRealSubId(subId)??
                        logd("DataStateReceiver: ignore invalid subId=" + subId);
                        return;
                    }
                    if (!SubscriptionManager.isValidPhoneId(phoneId)) {
                        logd("DataStateReceiver: ignore invalid phoneId=" + phoneId);
                        return;
                    }

                    boolean prevPowerOff = mServicePowerOffFlag[phoneId];
                    if (ss != null) {
                        int state = ss.getState();
                        switch (state) {
                            case ServiceState.STATE_POWER_OFF:
                                mServicePowerOffFlag[phoneId] = true;
                                logd("DataStateReceiver: STATE_POWER_OFF Intent from phoneId="
                                        + phoneId);
                                break;
                            case ServiceState.STATE_IN_SERVICE:
                                mServicePowerOffFlag[phoneId] = false;
                                logd("DataStateReceiver: STATE_IN_SERVICE Intent from phoneId="
                                        + phoneId);
                                break;
                            case ServiceState.STATE_OUT_OF_SERVICE:
                                logd("DataStateReceiver: STATE_OUT_OF_SERVICE Intent from phoneId="
                                        + phoneId);
                                if (mServicePowerOffFlag[phoneId]) {
                                    mServicePowerOffFlag[phoneId] = false;
                                }
                                break;
                            case ServiceState.STATE_EMERGENCY_ONLY:
                                logd("DataStateReceiver: STATE_EMERGENCY_ONLY Intent from phoneId="
                                        + phoneId);
                                break;
                            default:
                                logd("DataStateReceiver: SERVICE_STATE_CHANGED invalid state");
                                break;
                        }

                        if (prevPowerOff && mServicePowerOffFlag[phoneId] == false &&
                                mCurrentDataPhone == PHONE_NONE &&
                                phoneId == getDataConnectionFromSetting()) {
                            logd("DataStateReceiver: Current Phone is none and default phoneId="
                                    + phoneId + ", then enableApnType()");
                            enableApnType(subId, PhoneConstants.APN_TYPE_DEFAULT);
                        }
                    }
                }
            }
        }
    }

    public DefaultPhoneNotifier.IDataStateChangedCallback getDataStateChangedCallback() {
        return mDataStateChangedCallback;
    }

    public static DctController getInstance() {
       if (sDctController == null) {
        throw new RuntimeException(
            "DCTrackerController.getInstance can't be called before makeDCTController()");
        }
       return sDctController;
    }

    public static DctController makeDctController(PhoneProxy[] phones) {
        if (sDctController == null) {
            sDctController = new DctController(phones);
        }
        return sDctController;
    }

    private DctController(PhoneProxy[] phones) {
        if (phones == null || phones.length == 0) {
            if (phones == null) {
                loge("DctController(phones): UNEXPECTED phones=null, ignore");
            } else {
                loge("DctController(phones): UNEXPECTED phones.length=0, ignore");
            }
            return;
        }
        mPhoneNum = phones.length;
        mServicePowerOffFlag = new boolean[mPhoneNum];
        mPhones = phones;

        mDcSwitchState = new DcSwitchState[mPhoneNum];
        mDcSwitchAsyncChannel = new DcSwitchAsyncChannel[mPhoneNum];
        mDcSwitchStateHandler = new Handler[mPhoneNum];

        mActivePhone = mPhones[0];

        for (int i = 0; i < mPhoneNum; ++i) {
            int phoneId = i;
            mServicePowerOffFlag[i] = true;
            mDcSwitchState[i] = new DcSwitchState(mPhones[i], "DcSwitchState-" + phoneId, phoneId);
            mDcSwitchState[i].start();
            mDcSwitchAsyncChannel[i] = new DcSwitchAsyncChannel(mDcSwitchState[i], phoneId);
            mDcSwitchStateHandler[i] = new Handler();

            int status = mDcSwitchAsyncChannel[i].fullyConnectSync(mPhones[i].getContext(),
                mDcSwitchStateHandler[i], mDcSwitchState[i].getHandler());

            if (status == AsyncChannel.STATUS_SUCCESSFUL) {
                logd("DctController(phones): Connect success: " + i);
            } else {
                loge("DctController(phones): Could not connect to " + i);
            }

            mDcSwitchState[i].registerForIdle(mRspHander, EVENT_PHONE1_DETACH + i, null);

            // Register for radio state change
            PhoneBase phoneBase = (PhoneBase)((PhoneProxy)mPhones[i]).getActivePhone();
            phoneBase.mCi.registerForOffOrNotAvailable(mRspHander, EVENT_PHONE1_RADIO_OFF + i, null);
        }

        mContext = mActivePhone.getContext();

        IntentFilter filter = new IntentFilter();
        filter.addAction(TelephonyIntents.ACTION_DATA_CONNECTION_FAILED);
        filter.addAction(TelephonyIntents.ACTION_SERVICE_STATE_CHANGED);

        mDataStateReceiver = new DataStateReceiver();
        Intent intent = mContext.registerReceiver(mDataStateReceiver, filter);
    }

    private IccCardConstants.State getIccCardState(int phoneId) {
        return mPhones[phoneId].getIccCard().getState();
    }

    /**
     * Enable PDP interface by apn type and phone id
     *
     * @param type enable pdp interface by apn type, such as PhoneConstants.APN_TYPE_MMS, etc.
     * @param subId Indicate which sub to query
     * @return PhoneConstants.APN_REQUEST_STARTED: action is already started
     * PhoneConstants.APN_ALREADY_ACTIVE: interface has already active
     * PhoneConstants.APN_TYPE_NOT_AVAILABLE: invalid APN type
     * PhoneConstants.APN_REQUEST_FAILED: request failed
     * PhoneConstants.APN_REQUEST_FAILED_DUE_TO_RADIO_OFF: readio turn off
     * @see #disableApnType()
     */
    public synchronized int enableApnType(long subId, String type) {
        int phoneId = SubscriptionManager.getPhoneId(subId);

        if (phoneId == PHONE_NONE || !isValidphoneId(phoneId)) {
            logw("enableApnType(): with PHONE_NONE or Invalid PHONE ID");
            return PhoneConstants.APN_REQUEST_FAILED;
        }

        logd("enableApnType():type=" + type + ",phoneId=" + phoneId +
                ",powerOff=" + mServicePowerOffFlag[phoneId]);

        if (!PhoneConstants.APN_TYPE_DEFAULT.equals(type)) {
            for (int peerphoneId =0; peerphoneId < mPhoneNum; peerphoneId++) {
                // check peer Phone has non default APN activated as receiving non default APN request.
                if (phoneId == peerphoneId) {
                    continue;
                }

                String[] activeApnTypes = mPhones[peerphoneId].getActiveApnTypes();
                if (activeApnTypes != null && activeApnTypes.length != 0) {
                    for (int i=0; i<activeApnTypes.length; i++) {
                        if (!PhoneConstants.APN_TYPE_DEFAULT.equals(activeApnTypes[i]) &&
                                mPhones[peerphoneId].getDataConnectionState(activeApnTypes[i]) !=
                                PhoneConstants.DataState.DISCONNECTED) {
                            logd("enableApnType:Peer Phone still have non-default active APN type:"+
                                    "activeApnTypes[" + i + "]=" + activeApnTypes[i]);
                            return PhoneConstants.APN_REQUEST_FAILED;
                        }
                    }
                }
            }
        }

        logd("enableApnType(): CurrentDataPhone=" +
                    mCurrentDataPhone + ", RequestedDataPhone=" + mRequestedDataPhone);

        if (phoneId == mCurrentDataPhone &&
               !mDcSwitchAsyncChannel[mCurrentDataPhone].isIdleOrDeactingSync()) {
           mRequestedDataPhone = PHONE_NONE;
           logd("enableApnType(): mRequestedDataPhone equals request PHONE ID.");
           return mDcSwitchAsyncChannel[phoneId].connectSync(type);
        } else {
            // Only can switch data when mCurrentDataPhone is PHONE_NONE,
            // it is set to PHONE_NONE only as receiving EVENT_PHONEX_DETACH
            if (mCurrentDataPhone == PHONE_NONE) {
                mCurrentDataPhone = phoneId;
                mRequestedDataPhone = PHONE_NONE;
                logd("enableApnType(): current PHONE is NONE or IDLE, mCurrentDataPhone=" +
                        mCurrentDataPhone);
                return mDcSwitchAsyncChannel[phoneId].connectSync(type);
            } else {
                logd("enableApnType(): current PHONE:" + mCurrentDataPhone + " is active.");
                if (phoneId != mRequestedDataPhone) {
                    mApnTypes.clear();
                }
                mApnTypes.add(type);
                mRequestedDataPhone = phoneId;
                mDcSwitchState[mCurrentDataPhone].cleanupAllConnection();
            }
        }
        return PhoneConstants.APN_REQUEST_STARTED;
    }

    /**
     * disable PDP interface by apn type and sub id
     *
     * @param type enable pdp interface by apn type, such as PhoneConstants.APN_TYPE_MMS, etc.
     * @param subId Indicate which sub to query
     * @return PhoneConstants.APN_REQUEST_STARTED: action is already started
     * PhoneConstants.APN_ALREADY_ACTIVE: interface has already active
     * PhoneConstants.APN_TYPE_NOT_AVAILABLE: invalid APN type
     * PhoneConstants.APN_REQUEST_FAILED: request failed
     * PhoneConstants.APN_REQUEST_FAILED_DUE_TO_RADIO_OFF: readio turn off
     * @see #enableApnTypeGemini()
     */
    public synchronized int disableApnType(long subId, String type) {

        int phoneId = SubscriptionManager.getPhoneId(subId);

        if (phoneId == PHONE_NONE || !isValidphoneId(phoneId)) {
            logw("disableApnType(): with PHONE_NONE or Invalid PHONE ID");
            return PhoneConstants.APN_REQUEST_FAILED;
        }
        logd("disableApnType():type=" + type + ",phoneId=" + phoneId +
                ",powerOff=" + mServicePowerOffFlag[phoneId]);
        return mDcSwitchAsyncChannel[phoneId].disconnectSync(type);
    }

    public boolean isDataConnectivityPossible(String type, int phoneId) {
        if (phoneId == PHONE_NONE || !isValidphoneId(phoneId)) {
            logw("isDataConnectivityPossible(): with PHONE_NONE or Invalid PHONE ID");
            return false;
        } else {
            return mPhones[phoneId].isDataConnectivityPossible(type);
        }
    }

    public boolean isIdleOrDeacting(int phoneId) {
        if (mDcSwitchAsyncChannel[phoneId].isIdleOrDeactingSync()) {
            return true;
        } else {
            return false;
        }
    }

    private boolean isValidphoneId(int phoneId) {
        return phoneId >= 0 && phoneId <= mPhoneNum;
    }

    private boolean isValidApnType(String apnType) {
         if (apnType.equals(PhoneConstants.APN_TYPE_DEFAULT)
             || apnType.equals(PhoneConstants.APN_TYPE_MMS)
             || apnType.equals(PhoneConstants.APN_TYPE_SUPL)
             || apnType.equals(PhoneConstants.APN_TYPE_DUN)
             || apnType.equals(PhoneConstants.APN_TYPE_HIPRI)
             || apnType.equals(PhoneConstants.APN_TYPE_FOTA)
             || apnType.equals(PhoneConstants.APN_TYPE_IMS)
             || apnType.equals(PhoneConstants.APN_TYPE_CBS))
        {
            return true;
        } else {
            return false;
        }
    }

    private int getDataConnectionFromSetting(){
        long [] subId = SubscriptionManager.getSubId(PhoneConstants.SIM_ID_1);
        int phoneId = SubscriptionManager.getPhoneId(subId[0]);
        return phoneId;
    }

    private static void logv(String s) {
        Log.v(LOG_TAG, "[DctController] " + s);
    }

    private static void logd(String s) {
        Log.d(LOG_TAG, "[DctController] " + s);
    }

    private static void logw(String s) {
        Log.w(LOG_TAG, "[DctController] " + s);
    }

    private static void loge(String s) {
        Log.e(LOG_TAG, "[DctController] " + s);
    }


    public void setDataSubId(long subId) {
        //FIXME This should rework
        //FIXME Need to have a StateMachine logic to handle this api considering various clients
        Rlog.d(LOG_TAG, "setDataAllowed subId :" + subId);
        int phoneId = mSubController.getPhoneId(subId);
        int prefPhoneId = mSubController.getPhoneId(mSubController.getDefaultDataSubId());
        Phone phone = mPhones[prefPhoneId].getActivePhone();
        DcTrackerBase dcTracker =((PhoneBase)phone).mDcTracker;
        dcTracker.setDataAllowed(false, null);
        mPhones[prefPhoneId].registerForAllDataDisconnected(
                this, EVENT_ALL_DATA_DISCONNECTED, new Integer(phoneId));

    }

    public void registerForDataSwitchInfo(Handler h, int what, Object obj) {
        //FIXME This should rework
        Registrant r = new Registrant (h, what, obj);
        synchronized (mNotifyDataSwitchInfo) {
            mNotifyDataSwitchInfo.add(r);
        }
    }

    @Override
    public void handleMessage (Message msg) {
        //FIXME This should rework
            AsyncResult ar = (AsyncResult)msg.obj;
            Rlog.d(LOG_TAG, "handleMessage msg=" + msg);

            switch (msg.what) {
                case EVENT_ALL_DATA_DISCONNECTED:
                    Integer phoneId = (Integer)ar.userObj;
                    int prefPhoneId = mSubController.getPhoneId(
                            mSubController.getDefaultDataSubId());
                    Rlog.d(LOG_TAG, "EVENT_ALL_DATA_DISCONNECTED phoneId :" + phoneId);
                    mPhones[prefPhoneId].unregisterForAllDataDisconnected(this);
                    Message alllowedDataDone = Message.obtain(this, EVENT_SET_DATA_ALLOW_DONE,
                            new Integer(phoneId));
                    Phone phone = mPhones[phoneId].getActivePhone();
                    DcTrackerBase dcTracker =((PhoneBase)phone).mDcTracker;
                    dcTracker.setDataAllowed(true, alllowedDataDone);
                    break;

                case EVENT_SET_DATA_ALLOW_DONE:
                    phoneId = (Integer)ar.userObj;
                    long[] subId = mSubController.getSubId(phoneId);
                    Rlog.d(LOG_TAG, "EVENT_SET_DATA_ALLOWED_DONE  phoneId :" + subId[0]);
                    mNotifyDataSwitchInfo.notifyRegistrants(new AsyncResult(null, subId[0], null));
                    mPhones[phoneId].updateDataConnectionTracker();
                    break;
            }
    }
}