/*
 * 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.internal.telephony.dataconnection;

import android.content.Context;
import android.os.PersistableBundle;
import android.telephony.CarrierConfigManager;
import android.telephony.Rlog;
import android.telephony.ServiceState;
import android.text.TextUtils;

import com.android.internal.telephony.PhoneConstants;
import com.android.internal.telephony.RILConstants;
import com.android.internal.telephony.uicc.IccRecords;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Locale;

/**
 * This class represents a apn setting for create PDP link
 */
public class ApnSetting {

    static final String LOG_TAG = "ApnSetting";

    private static final boolean DBG = false;

    static final String V2_FORMAT_REGEX = "^\\[ApnSettingV2\\]\\s*";
    static final String V3_FORMAT_REGEX = "^\\[ApnSettingV3\\]\\s*";

    public final String carrier;
    public final String apn;
    public final String proxy;
    public final String port;
    public final String mmsc;
    public final String mmsProxy;
    public final String mmsPort;
    public final String user;
    public final String password;
    public final int authType;
    public final String[] types;
    public final int id;
    public final String numeric;
    public final String protocol;
    public final String roamingProtocol;
    public final int mtu;

    /**
      * Current status of APN
      * true : enabled APN, false : disabled APN.
      */
    public final boolean carrierEnabled;
    /**
     * Radio Access Technology info
     * To check what values can hold, refer to ServiceState.java.
     * This should be spread to other technologies,
     * but currently only used for LTE(14) and EHRPD(13).
     */
    private final int bearer;
    /**
      * Radio Access Technology info
      * To check what values can hold, refer to ServiceState.java. This is a bitmask of radio
      * technologies in ServiceState.
      * This should be spread to other technologies,
      * but currently only used for LTE(14) and EHRPD(13).
      */
    public final int bearerBitmask;

    /* ID of the profile in the modem */
    public final int profileId;
    public final boolean modemCognitive;
    public final int maxConns;
    public final int waitTime;
    public final int maxConnsTime;

    /**
      * MVNO match type. Possible values:
      *   "spn": Service provider name.
      *   "imsi": IMSI.
      *   "gid": Group identifier level 1.
      */
    public final String mvnoType;
    /**
      * MVNO data. Examples:
      *   "spn": A MOBILE, BEN NL
      *   "imsi": 302720x94, 2060188
      *   "gid": 4E, 33
      */
    public final String mvnoMatchData;

    /**
     * Indicates this APN setting is permanently failed and cannot be
     * retried by the retry manager anymore.
     * */
    public boolean permanentFailed = false;

    /**
     * Metered APN types which would be accounted for in data usage. This is a map of subId ->
     * set of metered apn strings for the carrier.
     */
    private static HashMap<Integer, HashSet<String>> sMeteredApnTypes = new HashMap<>();

    /**
     * Metered Roaming APN types which would be accounted for in data usage. This is a map of
     * subId -> set of metered roaming apn strings for the carrier.
     */
    private static HashMap<Integer, HashSet<String>> sMeteredRoamingApnTypes = new HashMap<>();

    public ApnSetting(int id, String numeric, String carrier, String apn,
            String proxy, String port,
            String mmsc, String mmsProxy, String mmsPort,
            String user, String password, int authType, String[] types,
            String protocol, String roamingProtocol, boolean carrierEnabled, int bearer,
            int bearerBitmask, int profileId, boolean modemCognitive, int maxConns, int waitTime,
            int maxConnsTime, int mtu, String mvnoType, String mvnoMatchData) {
        this.id = id;
        this.numeric = numeric;
        this.carrier = carrier;
        this.apn = apn;
        this.proxy = proxy;
        this.port = port;
        this.mmsc = mmsc;
        this.mmsProxy = mmsProxy;
        this.mmsPort = mmsPort;
        this.user = user;
        this.password = password;
        this.authType = authType;
        this.types = new String[types.length];
        for (int i = 0; i < types.length; i++) {
            this.types[i] = types[i].toLowerCase(Locale.ROOT);
        }
        this.protocol = protocol;
        this.roamingProtocol = roamingProtocol;
        this.carrierEnabled = carrierEnabled;
        this.bearer = bearer;
        this.bearerBitmask = (bearerBitmask | ServiceState.getBitmaskForTech(bearer));
        this.profileId = profileId;
        this.modemCognitive = modemCognitive;
        this.maxConns = maxConns;
        this.waitTime = waitTime;
        this.maxConnsTime = maxConnsTime;
        this.mtu = mtu;
        this.mvnoType = mvnoType;
        this.mvnoMatchData = mvnoMatchData;

    }

    public ApnSetting(ApnSetting apn) {
        this(apn.id, apn.numeric, apn.carrier, apn.apn, apn.proxy, apn.port, apn.mmsc, apn.mmsProxy,
                apn.mmsPort, apn.user, apn.password, apn.authType, apn.types, apn.protocol,
                apn.roamingProtocol, apn.carrierEnabled, apn.bearer, apn.bearerBitmask,
                apn.profileId, apn.modemCognitive, apn.maxConns, apn.waitTime, apn.maxConnsTime,
                apn.mtu, apn.mvnoType, apn.mvnoMatchData);
    }

    /**
     * Creates an ApnSetting object from a string.
     *
     * @param data the string to read.
     *
     * The string must be in one of two formats (newlines added for clarity,
     * spaces are optional):
     *
     * v1 format:
     *   <carrier>, <apn>, <proxy>, <port>, <user>, <password>, <server>,
     *   <mmsc>, <mmsproxy>, <mmsport>, <mcc>, <mnc>, <authtype>,
     *   <type>[| <type>...],
     *
     * v2 format:
     *   [ApnSettingV2] <carrier>, <apn>, <proxy>, <port>, <user>, <password>, <server>,
     *   <mmsc>, <mmsproxy>, <mmsport>, <mcc>, <mnc>, <authtype>,
     *   <type>[| <type>...], <protocol>, <roaming_protocol>, <carrierEnabled>, <bearerBitmask>,
     *
     * v3 format:
     *   [ApnSettingV3] <carrier>, <apn>, <proxy>, <port>, <user>, <password>, <server>,
     *   <mmsc>, <mmsproxy>, <mmsport>, <mcc>, <mnc>, <authtype>,
     *   <type>[| <type>...], <protocol>, <roaming_protocol>, <carrierEnabled>, <bearerBitmask>,
     *   <profileId>, <modemCognitive>, <maxConns>, <waitTime>, <maxConnsTime>, <mtu>,
     *   <mvnoType>, <mvnoMatchData>
     *
     * Note that the strings generated by toString() do not contain the username
     * and password and thus cannot be read by this method.
     */
    public static ApnSetting fromString(String data) {
        if (data == null) return null;

        int version;
        // matches() operates on the whole string, so append .* to the regex.
        if (data.matches(V3_FORMAT_REGEX + ".*")) {
            version = 3;
            data = data.replaceFirst(V3_FORMAT_REGEX, "");
        } else if (data.matches(V2_FORMAT_REGEX + ".*")) {
            version = 2;
            data = data.replaceFirst(V2_FORMAT_REGEX, "");
        } else {
            version = 1;
        }

        String[] a = data.split("\\s*,\\s*");
        if (a.length < 14) {
            return null;
        }

        int authType;
        try {
            authType = Integer.parseInt(a[12]);
        } catch (NumberFormatException e) {
            authType = 0;
        }

        String[] typeArray;
        String protocol, roamingProtocol;
        boolean carrierEnabled;
        int bearerBitmask = 0;
        int profileId = 0;
        boolean modemCognitive = false;
        int maxConns = 0;
        int waitTime = 0;
        int maxConnsTime = 0;
        int mtu = PhoneConstants.UNSET_MTU;
        String mvnoType = "";
        String mvnoMatchData = "";
        if (version == 1) {
            typeArray = new String[a.length - 13];
            System.arraycopy(a, 13, typeArray, 0, a.length - 13);
            protocol = RILConstants.SETUP_DATA_PROTOCOL_IP;
            roamingProtocol = RILConstants.SETUP_DATA_PROTOCOL_IP;
            carrierEnabled = true;
        } else {
            if (a.length < 18) {
                return null;
            }
            typeArray = a[13].split("\\s*\\|\\s*");
            protocol = a[14];
            roamingProtocol = a[15];
            carrierEnabled = Boolean.parseBoolean(a[16]);

            bearerBitmask = ServiceState.getBitmaskFromString(a[17]);

            if (a.length > 22) {
                modemCognitive = Boolean.parseBoolean(a[19]);
                try {
                    profileId = Integer.parseInt(a[18]);
                    maxConns = Integer.parseInt(a[20]);
                    waitTime = Integer.parseInt(a[21]);
                    maxConnsTime = Integer.parseInt(a[22]);
                } catch (NumberFormatException e) {
                }
            }
            if (a.length > 23) {
                try {
                    mtu = Integer.parseInt(a[23]);
                } catch (NumberFormatException e) {
                }
            }
            if (a.length > 25) {
                mvnoType = a[24];
                mvnoMatchData = a[25];
            }
        }

        return new ApnSetting(-1,a[10]+a[11],a[0],a[1],a[2],a[3],a[7],a[8],
                a[9],a[4],a[5],authType,typeArray,protocol,roamingProtocol,carrierEnabled,0,
                bearerBitmask, profileId, modemCognitive, maxConns, waitTime, maxConnsTime, mtu,
                mvnoType, mvnoMatchData);
    }

    /**
     * Creates an array of ApnSetting objects from a string.
     *
     * @param data the string to read.
     *
     * Builds on top of the same format used by fromString, but allows for multiple entries
     * separated by "; ".
     */
    public static List<ApnSetting> arrayFromString(String data) {
        List<ApnSetting> retVal = new ArrayList<ApnSetting>();
        if (TextUtils.isEmpty(data)) {
            return retVal;
        }
        String[] apnStrings = data.split("\\s*;\\s*");
        for (String apnString : apnStrings) {
            ApnSetting apn = fromString(apnString);
            if (apn != null) {
                retVal.add(apn);
            }
        }
        return retVal;
    }

    @Override
    public String toString() {
        StringBuilder sb = new StringBuilder();
        sb.append("[ApnSettingV3] ")
        .append(carrier)
        .append(", ").append(id)
        .append(", ").append(numeric)
        .append(", ").append(apn)
        .append(", ").append(proxy)
        .append(", ").append(mmsc)
        .append(", ").append(mmsProxy)
        .append(", ").append(mmsPort)
        .append(", ").append(port)
        .append(", ").append(authType).append(", ");
        for (int i = 0; i < types.length; i++) {
            sb.append(types[i]);
            if (i < types.length - 1) {
                sb.append(" | ");
            }
        }
        sb.append(", ").append(protocol);
        sb.append(", ").append(roamingProtocol);
        sb.append(", ").append(carrierEnabled);
        sb.append(", ").append(bearer);
        sb.append(", ").append(bearerBitmask);
        sb.append(", ").append(profileId);
        sb.append(", ").append(modemCognitive);
        sb.append(", ").append(maxConns);
        sb.append(", ").append(waitTime);
        sb.append(", ").append(maxConnsTime);
        sb.append(", ").append(mtu);
        sb.append(", ").append(mvnoType);
        sb.append(", ").append(mvnoMatchData);
        sb.append(", ").append(permanentFailed);
        return sb.toString();
    }

    /**
     * Returns true if there are MVNO params specified.
     */
    public boolean hasMvnoParams() {
        return !TextUtils.isEmpty(mvnoType) && !TextUtils.isEmpty(mvnoMatchData);
    }

    public boolean canHandleType(String type) {
        if (!carrierEnabled) return false;
        for (String t : types) {
            // DEFAULT handles all, and HIPRI is handled by DEFAULT
            if (t.equalsIgnoreCase(type) ||
                    t.equalsIgnoreCase(PhoneConstants.APN_TYPE_ALL) ||
                    (t.equalsIgnoreCase(PhoneConstants.APN_TYPE_DEFAULT) &&
                    type.equalsIgnoreCase(PhoneConstants.APN_TYPE_HIPRI))) {
                return true;
            }
        }
        return false;
    }

    private static boolean imsiMatches(String imsiDB, String imsiSIM) {
        // Note: imsiDB value has digit number or 'x' character for seperating USIM information
        // for MVNO operator. And then digit number is matched at same order and 'x' character
        // could replace by any digit number.
        // ex) if imsiDB inserted '310260x10xxxxxx' for GG Operator,
        //     that means first 6 digits, 8th and 9th digit
        //     should be set in USIM for GG Operator.
        int len = imsiDB.length();
        int idxCompare = 0;

        if (len <= 0) return false;
        if (len > imsiSIM.length()) return false;

        for (int idx=0; idx<len; idx++) {
            char c = imsiDB.charAt(idx);
            if ((c == 'x') || (c == 'X') || (c == imsiSIM.charAt(idx))) {
                continue;
            } else {
                return false;
            }
        }
        return true;
    }

    public static boolean mvnoMatches(IccRecords r, String mvnoType, String mvnoMatchData) {
        if (mvnoType.equalsIgnoreCase("spn")) {
            if ((r.getServiceProviderName() != null) &&
                    r.getServiceProviderName().equalsIgnoreCase(mvnoMatchData)) {
                return true;
            }
        } else if (mvnoType.equalsIgnoreCase("imsi")) {
            String imsiSIM = r.getIMSI();
            if ((imsiSIM != null) && imsiMatches(mvnoMatchData, imsiSIM)) {
                return true;
            }
        } else if (mvnoType.equalsIgnoreCase("gid")) {
            String gid1 = r.getGid1();
            int mvno_match_data_length = mvnoMatchData.length();
            if ((gid1 != null) && (gid1.length() >= mvno_match_data_length) &&
                    gid1.substring(0, mvno_match_data_length).equalsIgnoreCase(mvnoMatchData)) {
                return true;
            }
        }
        return false;
    }

    public static boolean isMeteredApnType(String type, Context context, int subId,
                                           boolean isRoaming) {

        HashMap<Integer, HashSet<String>> meteredApnTypesCache = (isRoaming) ?
                sMeteredApnTypes : sMeteredRoamingApnTypes;
        String carrierConfig = (isRoaming) ?
                CarrierConfigManager.KEY_CARRIER_METERED_ROAMING_APN_TYPES_STRINGS :
                CarrierConfigManager.KEY_CARRIER_METERED_APN_TYPES_STRINGS;

        synchronized (meteredApnTypesCache) {
            HashSet<String> meteredApnSet = meteredApnTypesCache.get(subId);

            // In case of cache miss, we need to look up the settings from carrier config.
            if (meteredApnSet == null) {
                // Retrieve the metered APN types from carrier config
                CarrierConfigManager configManager = (CarrierConfigManager)
                        context.getSystemService(Context.CARRIER_CONFIG_SERVICE);
                if (configManager == null) {
                    Rlog.e(LOG_TAG, "Carrier config service is not available");
                    return true;
                }

                PersistableBundle b = configManager.getConfigForSubId(subId);
                if (b == null) {
                    Rlog.e(LOG_TAG, "Can't get the config. subId = " + subId);
                    return true;
                }

                String[] meteredApnTypes = b.getStringArray(carrierConfig);
                if (meteredApnTypes == null) {
                    Rlog.e(LOG_TAG, carrierConfig +  " is not available. " + "subId = " + subId);
                    return true;
                }

                meteredApnSet = new HashSet<String>(Arrays.asList(meteredApnTypes));
                meteredApnTypesCache.put(subId, meteredApnSet);
                if (DBG) {
                    Rlog.d(LOG_TAG, "For subId = " + subId + ", metered APN types are " +
                            Arrays.toString(meteredApnSet.toArray()) +
                            " isRoaming: " + isRoaming);
                }
            }
            // If all types of APN are metered, then this APN setting must be metered.
            if (meteredApnSet.contains(PhoneConstants.APN_TYPE_ALL)) {
                if (DBG) Rlog.d(LOG_TAG, "All APN types are metered. isRoaming: " + isRoaming);
                return true;
            }

            if (meteredApnSet.contains(type)) {
                if (DBG) Rlog.d(LOG_TAG, type + " is metered. isRoaming: " + isRoaming);
                return true;
            } else if (type.equals(PhoneConstants.APN_TYPE_ALL)) {
                // Assuming no configuration error, if at least one APN type is
                // metered, then this APN setting is metered.
                if (meteredApnSet.size() > 0) {
                    if (DBG) Rlog.d(LOG_TAG, "APN_TYPE_ALL APN is metered. isRoaming: " +
                            isRoaming);
                    return true;
                }
            }
        }
        if (DBG) Rlog.d(LOG_TAG, type + " is not metered. isRoaming: " + isRoaming);
        return false;
    }

    public boolean isMetered(Context context, int subId, boolean isRoaming ) {
        for (String type : types) {
            // If one of the APN type is metered, then this APN setting is metered.
            if (isMeteredApnType(type, context, subId, isRoaming)) {
                if (DBG) Rlog.d(LOG_TAG, "Metered. APN = " + toString() +
                        "isRoaming: " + isRoaming);
                return true;
            }
        }
        if (DBG) Rlog.d(LOG_TAG, "Not metered. APN = " + toString() + "isRoaming: " + isRoaming);
        return false;
    }

    // TODO - if we have this function we should also have hashCode.
    // Also should handle changes in type order and perhaps case-insensitivity
    @Override
    public boolean equals(Object o) {
        if (o instanceof ApnSetting == false) {
            return false;
        }

        ApnSetting other = (ApnSetting) o;

        return carrier.equals(other.carrier) &&
                id == other.id &&
                numeric.equals(other.numeric) &&
                apn.equals(other.apn) &&
                proxy.equals(other.proxy) &&
                mmsc.equals(other.mmsc) &&
                mmsProxy.equals(other.mmsProxy) &&
                port.equals(other.port) &&
                authType == other.authType &&
                Arrays.deepEquals(types, other.types) &&
                protocol.equals(other.protocol) &&
                roamingProtocol.equals(other.roamingProtocol) &&
                carrierEnabled == other.carrierEnabled &&
                bearer == other.bearer &&
                bearerBitmask == other.bearerBitmask &&
                profileId == other.profileId &&
                modemCognitive == other.modemCognitive &&
                maxConns == other.maxConns &&
                waitTime == other.waitTime &&
                maxConnsTime == other.maxConnsTime &&
                mtu == other.mtu &&
                mvnoType.equals(other.mvnoType) &&
                mvnoMatchData.equals(other.mvnoMatchData);
    }
}