service/java/com/android/server/wifi/ScoringParams.java - platform/packages/modules/Wifi - Git at Google

 /*
  * Copyright 2018 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.server.wifi;

 import android.annotation.NonNull;
 import android.content.Context;
 import android.net.wifi.ScanResult;
 import android.net.wifi.WifiInfo;
 import android.util.Log;

 import com.android.internal.annotations.VisibleForTesting;
 import com.android.server.wifi.util.KeyValueListParser;
 import com.android.wifi.resources.R;

 /**
  * Holds parameters used for scoring networks.
  *
  * Doing this in one place means that there's a better chance of consistency between
  * connected score and network selection.
  *
  */
 public class ScoringParams {
     private final Context mContext;

     private static final String TAG = "WifiScoringParams";
     private static final int EXIT = 0;
     private static final int ENTRY = 1;
     private static final int SUFFICIENT = 2;
     private static final int GOOD = 3;

     private static final int ACTIVE_TRAFFIC = 1;
     private static final int HIGH_TRAFFIC = 2;
     /**
      * Parameter values are stored in a separate container so that a new collection of values can
      * be checked for consistency before activating them.
      */
     private class Values {
         /** RSSI thresholds for 2.4 GHz band (dBm) */
         public static final String KEY_RSSI2 = "rssi2";
         public final int[] rssi2 = {-83, -80, -73, -60};

         /** RSSI thresholds for 5 GHz band (dBm) */
         public static final String KEY_RSSI5 = "rssi5";
         public final int[] rssi5 = {-80, -77, -70, -57};

         /** RSSI thresholds for 6 GHz band (dBm) */
         public static final String KEY_RSSI6 = "rssi6";
         public final int[] rssi6 = {-80, -77, -70, -57};

        /** Guidelines based on packet rates (packets/sec) */
         public static final String KEY_PPS = "pps";
         public final int[] pps = {0, 1, 100};

         /** Number of seconds for RSSI forecast */
         public static final String KEY_HORIZON = "horizon";
         public static final int MIN_HORIZON = -9;
         public static final int MAX_HORIZON = 60;
         public int horizon = 15;

         /** Number 0-10 influencing requests for network unreachability detection */
         public static final String KEY_NUD = "nud";
         public static final int MIN_NUD = 0;
         public static final int MAX_NUD = 10;
         public int nud = 8;

         /** Experiment identifier */
         public static final String KEY_EXPID = "expid";
         public static final int MIN_EXPID = 0;
         public static final int MAX_EXPID = Integer.MAX_VALUE;
         public int expid = 0;

         /** CandidateScorer parameters */
         public int throughputBonusNumerator = 120;
         public int throughputBonusDenominator = 433;
         public int throughputBonusLimit = 200;
         public int savedNetworkBonus = 500;
         public int unmeteredNetworkBonus = 1000;
         public int currentNetworkBonusMin = 20;
         public int currentNetworkBonusPercent = 20;
         public int secureNetworkBonus = 40;
         public int lastSelectionMinutes = 480;
         public int estimateRssiErrorMargin = 5;
         public static final int MIN_MINUTES = 1;
         public static final int MAX_MINUTES = Integer.MAX_VALUE / (60 * 1000);

         Values() {
         }

         Values(Values source) {
             for (int i = 0; i < rssi2.length; i++) {
                 rssi2[i] = source.rssi2[i];
             }
             for (int i = 0; i < rssi5.length; i++) {
                 rssi5[i] = source.rssi5[i];
             }
             for (int i = 0; i < rssi6.length; i++) {
                 rssi6[i] = source.rssi6[i];
             }
             for (int i = 0; i < pps.length; i++) {
                 pps[i] = source.pps[i];
             }
             horizon = source.horizon;
             nud = source.nud;
             expid = source.expid;
         }

         public void validate() throws IllegalArgumentException {
             validateRssiArray(rssi2);
             validateRssiArray(rssi5);
             validateRssiArray(rssi6);
             validateOrderedNonNegativeArray(pps);
             validateRange(horizon, MIN_HORIZON, MAX_HORIZON);
             validateRange(nud, MIN_NUD, MAX_NUD);
             validateRange(expid, MIN_EXPID, MAX_EXPID);
             validateRange(lastSelectionMinutes, MIN_MINUTES, MAX_MINUTES);
         }

         private void validateRssiArray(int[] rssi) throws IllegalArgumentException {
             int low = WifiInfo.MIN_RSSI;
             int high = Math.min(WifiInfo.MAX_RSSI, -1); // Stricter than Wifiinfo
             for (int i = 0; i < rssi.length; i++) {
                 validateRange(rssi[i], low, high);
                 low = rssi[i];
             }
         }

         private void validateRange(int k, int low, int high) throws IllegalArgumentException {
             if (k < low || k > high) {
                 throw new IllegalArgumentException();
             }
         }

         private void validateOrderedNonNegativeArray(int[] a) throws IllegalArgumentException {
             int low = 0;
             for (int i = 0; i < a.length; i++) {
                 if (a[i] < low) {
                     throw new IllegalArgumentException();
                 }
                 low = a[i];
             }
         }

         public void parseString(String kvList) throws IllegalArgumentException {
             KeyValueListParser parser = new KeyValueListParser(',');
             parser.setString(kvList);
             if (parser.size() != ("" + kvList).split(",").length) {
                 throw new IllegalArgumentException("dup keys");
             }
             updateIntArray(rssi2, parser, KEY_RSSI2);
             updateIntArray(rssi5, parser, KEY_RSSI5);
             updateIntArray(rssi6, parser, KEY_RSSI6);
             updateIntArray(pps, parser, KEY_PPS);
             horizon = updateInt(parser, KEY_HORIZON, horizon);
             nud = updateInt(parser, KEY_NUD, nud);
             expid = updateInt(parser, KEY_EXPID, expid);
         }

         private int updateInt(KeyValueListParser parser, String key, int defaultValue)
                 throws IllegalArgumentException {
             String value = parser.getString(key, null);
             if (value == null) return defaultValue;
             try {
                 return Integer.parseInt(value);
             } catch (NumberFormatException e) {
                 throw new IllegalArgumentException();
             }
         }

         private void updateIntArray(final int[] dest, KeyValueListParser parser, String key)
                 throws IllegalArgumentException {
             if (parser.getString(key, null) == null) return;
             int[] ints = parser.getIntArray(key, null);
             if (ints == null) throw new IllegalArgumentException();
             if (ints.length != dest.length) throw new IllegalArgumentException();
             for (int i = 0; i < dest.length; i++) {
                 dest[i] = ints[i];
             }
         }

         @Override
         public String toString() {
             StringBuilder sb = new StringBuilder();
             appendKey(sb, KEY_RSSI2);
             appendInts(sb, rssi2);
             appendKey(sb, KEY_RSSI5);
             appendInts(sb, rssi5);
             appendKey(sb, KEY_RSSI6);
             appendInts(sb, rssi6);
             appendKey(sb, KEY_PPS);
             appendInts(sb, pps);
             appendKey(sb, KEY_HORIZON);
             sb.append(horizon);
             appendKey(sb, KEY_NUD);
             sb.append(nud);
             appendKey(sb, KEY_EXPID);
             sb.append(expid);
             return sb.toString();
         }

         private void appendKey(StringBuilder sb, String key) {
             if (sb.length() != 0) sb.append(",");
             sb.append(key).append("=");
         }

         private void appendInts(StringBuilder sb, final int[] a) {
             final int n = a.length;
             for (int i = 0; i < n; i++) {
                 if (i > 0) sb.append(":");
                 sb.append(a[i]);
             }
         }
     }

     @NonNull private Values mVal = null;

     @VisibleForTesting
     public ScoringParams() {
         mContext = null;
         mVal = new Values();
     }

     public ScoringParams(Context context) {
         mContext = context;
     }

     private void loadResources(Context context) {
         if (mVal != null) return;
         mVal = new Values();
         mVal.rssi2[EXIT] = context.getResources().getInteger(
                 R.integer.config_wifi_framework_wifi_score_bad_rssi_threshold_24GHz);
         mVal.rssi2[ENTRY] = context.getResources().getInteger(
                 R.integer.config_wifi_framework_wifi_score_entry_rssi_threshold_24GHz);
         mVal.rssi2[SUFFICIENT] = context.getResources().getInteger(
                 R.integer.config_wifi_framework_wifi_score_low_rssi_threshold_24GHz);
         mVal.rssi2[GOOD] = context.getResources().getInteger(
                 R.integer.config_wifi_framework_wifi_score_good_rssi_threshold_24GHz);
         mVal.rssi5[EXIT] = context.getResources().getInteger(
                 R.integer.config_wifi_framework_wifi_score_bad_rssi_threshold_5GHz);
         mVal.rssi5[ENTRY] = context.getResources().getInteger(
                 R.integer.config_wifi_framework_wifi_score_entry_rssi_threshold_5GHz);
         mVal.rssi5[SUFFICIENT] = context.getResources().getInteger(
                 R.integer.config_wifi_framework_wifi_score_low_rssi_threshold_5GHz);
         mVal.rssi5[GOOD] = context.getResources().getInteger(
                 R.integer.config_wifi_framework_wifi_score_good_rssi_threshold_5GHz);
         mVal.rssi6[EXIT] = context.getResources().getInteger(
                 R.integer.config_wifiFrameworkScoreBadRssiThreshold6ghz);
         mVal.rssi6[ENTRY] = context.getResources().getInteger(
                 R.integer.config_wifiFrameworkScoreEntryRssiThreshold6ghz);
         mVal.rssi6[SUFFICIENT] = context.getResources().getInteger(
                 R.integer.config_wifiFrameworkScoreLowRssiThreshold6ghz);
         mVal.rssi6[GOOD] = context.getResources().getInteger(
                 R.integer.config_wifiFrameworkScoreGoodRssiThreshold6ghz);
         mVal.throughputBonusNumerator = context.getResources().getInteger(
                 R.integer.config_wifiFrameworkThroughputBonusNumerator);
         mVal.throughputBonusDenominator = context.getResources().getInteger(
                 R.integer.config_wifiFrameworkThroughputBonusDenominator);
         mVal.throughputBonusLimit = context.getResources().getInteger(
                 R.integer.config_wifiFrameworkThroughputBonusLimit);
         mVal.savedNetworkBonus = context.getResources().getInteger(
                 R.integer.config_wifiFrameworkSavedNetworkBonus);
         mVal.unmeteredNetworkBonus = context.getResources().getInteger(
                 R.integer.config_wifiFrameworkUnmeteredNetworkBonus);
         mVal.currentNetworkBonusMin = context.getResources().getInteger(
                 R.integer.config_wifiFrameworkCurrentNetworkBonusMin);
         mVal.currentNetworkBonusPercent = context.getResources().getInteger(
             R.integer.config_wifiFrameworkCurrentNetworkBonusPercent);
         mVal.secureNetworkBonus = context.getResources().getInteger(
                 R.integer.config_wifiFrameworkSecureNetworkBonus);
         mVal.lastSelectionMinutes = context.getResources().getInteger(
                 R.integer.config_wifiFrameworkLastSelectionMinutes);
         mVal.estimateRssiErrorMargin = context.getResources().getInteger(
                 R.integer.config_wifiEstimateRssiErrorMarginDb);
         mVal.pps[ACTIVE_TRAFFIC] = context.getResources().getInteger(
                 R.integer.config_wifiFrameworkMinPacketPerSecondActiveTraffic);
         mVal.pps[HIGH_TRAFFIC] = context.getResources().getInteger(
                 R.integer.config_wifiFrameworkMinPacketPerSecondHighTraffic);
         try {
             mVal.validate();
         } catch (IllegalArgumentException e) {
             Log.wtf(TAG, "Inconsistent config_wifi_framework_ resources: " + this, e);
         }
     }

     private static final String COMMA_KEY_VAL_STAR = "^(,[A-Za-z_][A-Za-z0-9_]*=[0-9.:+-]+)*$";

     /**
      * Updates the parameters from the given parameter string.
      * If any errors are detected, no change is made.
      * @param kvList is a comma-separated key=value list.
      * @return true for success
      */
     @VisibleForTesting
     public boolean update(String kvList) {
         if (kvList == null || "".equals(kvList)) {
             return true;
         }
         if (!("," + kvList).matches(COMMA_KEY_VAL_STAR)) {
             return false;
         }
         loadResources(mContext);
         Values v = new Values(mVal);
         try {
             v.parseString(kvList);
             v.validate();
             mVal = v;
             return true;
         } catch (IllegalArgumentException e) {
             return false;
         }
     }

     /**
      * Sanitize a string to make it safe for printing.
      * @param params is the untrusted string
      * @return string with questionable characters replaced with question marks
      */
     public String sanitize(String params) {
         if (params == null) return "";
         String printable = params.replaceAll("[^A-Za-z_0-9=,:.+-]", "?");
         if (printable.length() > 100) {
             printable = printable.substring(0, 98) + "...";
         }
         return printable;
     }

     /**
      * Returns the RSSI value at which the connection is deemed to be unusable,
      * in the absence of other indications.
      */
     public int getExitRssi(int frequencyMegaHertz) {
         return getRssiArray(frequencyMegaHertz)[EXIT];
     }

     /**
      * Returns the minimum scan RSSI for making a connection attempt.
      */
     public int getEntryRssi(int frequencyMegaHertz) {
         return getRssiArray(frequencyMegaHertz)[ENTRY];
     }

     /**
      * Returns a connected RSSI value that indicates the connection is
      * good enough that we needn't scan for alternatives.
      */
     public int getSufficientRssi(int frequencyMegaHertz) {
         return getRssiArray(frequencyMegaHertz)[SUFFICIENT];
     }

     /**
      * Returns a connected RSSI value that indicates a good connection.
      */
     public int getGoodRssi(int frequencyMegaHertz) {
         return getRssiArray(frequencyMegaHertz)[GOOD];
     }

     /**
      * Returns the number of seconds to use for rssi forecast.
      */
     public int getHorizonSeconds() {
         loadResources(mContext);
         return mVal.horizon;
     }

     /**
      * Returns a packet rate that should be considered acceptable for staying on wifi,
      * no matter how bad the RSSI gets (packets per second).
      */
     public int getYippeeSkippyPacketsPerSecond() {
         loadResources(mContext);
         return mVal.pps[HIGH_TRAFFIC];
     }

     /**
      * Returns a packet rate that should be considered acceptable to skip scan or network selection
      */
     public int getActiveTrafficPacketsPerSecond() {
         loadResources(mContext);
         return mVal.pps[ACTIVE_TRAFFIC];
     }

     /**
      * Returns a number between 0 and 10 inclusive that indicates
      * how aggressive to be about asking for IP configuration checks
      * (also known as Network Unreachabilty Detection, or NUD).
      *
      * 0 - no nud checks requested by scorer (framework still checks after roam)
      * 1 - check when score becomes very low
      *     ...
      * 10 - check when score first breaches threshold, and again as it gets worse
      *
      */
     public int getNudKnob() {
         loadResources(mContext);
         return mVal.nud;
     }

     /**
      * Returns the estimate rssi error margin to account minor differences in the environment
      * and the device's orientation.
      *
      */
     public int getEstimateRssiErrorMargin() {
         return mVal.estimateRssiErrorMargin;
     }

     /**
      */
     public int getThroughputBonusNumerator() {
         return mVal.throughputBonusNumerator;
     }

     /**
      */
     public int getThroughputBonusDenominator() {
         return mVal.throughputBonusDenominator;
     }

     /*
      * Returns the maximum bonus for the network selection candidate score
      * for the contribution of the selected score.
      */
     public int getThroughputBonusLimit() {
         return mVal.throughputBonusLimit;
     }

     /*
      * Returns the bonus for the network selection candidate score
      * for a saved network (i.e., not a suggestion).
      */
     public int getSavedNetworkBonus() {
         return mVal.savedNetworkBonus;
     }

     /*
      * Returns the bonus for the network selection candidate score
      * for an unmetered network.
      */
     public int getUnmeteredNetworkBonus() {
         return mVal.unmeteredNetworkBonus;
     }

     /*
      * Returns the minimum bonus for the network selection candidate score
      * for the currently connected network.
      */
     public int getCurrentNetworkBonusMin() {
         return mVal.currentNetworkBonusMin;
     }

     /*
      * Returns the percentage bonus for the network selection candidate score
      * for the currently connected network. The percent value is applied to rssi score and
      * throughput score;
      */
     public int getCurrentNetworkBonusPercent() {
         return mVal.currentNetworkBonusPercent;
     }

     /*
      * Returns the bonus for the network selection candidate score
      * for a secure network.
      */
     public int getSecureNetworkBonus() {
         return mVal.secureNetworkBonus;
     }

     /*
      * Returns the duration in minutes for a recently selected network
      * to be strongly favored.
      */
     public int getLastSelectionMinutes() {
         return mVal.lastSelectionMinutes;
     }

     /**
      * Returns the experiment identifier.
      *
      * This value may be used to tag a set of experimental settings.
      */
     public int getExperimentIdentifier() {
         loadResources(mContext);
         return mVal.expid;
     }

     private int[] getRssiArray(int frequency) {
         loadResources(mContext);
         if (ScanResult.is24GHz(frequency)) {
             return mVal.rssi2;
         } else if (ScanResult.is5GHz(frequency)) {
             return mVal.rssi5;
         } else if (ScanResult.is6GHz(frequency)) {
             return mVal.rssi6;
         }
         // Invalid frequency use
         Log.e(TAG, "Invalid frequency(" + frequency + "), using 5G as default rssi array");
         return mVal.rssi5;
     }

     @Override
     public String toString() {
         loadResources(mContext);
         return mVal.toString();
     }
 }
	/*
	* Copyright 2018 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.server.wifi;

	import android.annotation.NonNull;
	import android.content.Context;
	import android.net.wifi.ScanResult;
	import android.net.wifi.WifiInfo;
	import android.util.Log;

	import com.android.internal.annotations.VisibleForTesting;
	import com.android.server.wifi.util.KeyValueListParser;
	import com.android.wifi.resources.R;

	/**
	* Holds parameters used for scoring networks.
	*
	* Doing this in one place means that there's a better chance of consistency between
	* connected score and network selection.
	*
	*/
	public class ScoringParams {
	private final Context mContext;

	private static final String TAG = "WifiScoringParams";
	private static final int EXIT = 0;
	private static final int ENTRY = 1;
	private static final int SUFFICIENT = 2;
	private static final int GOOD = 3;

	private static final int ACTIVE_TRAFFIC = 1;
	private static final int HIGH_TRAFFIC = 2;
	/**
	* Parameter values are stored in a separate container so that a new collection of values can
	* be checked for consistency before activating them.
	*/
	private class Values {
	/** RSSI thresholds for 2.4 GHz band (dBm) */
	public static final String KEY_RSSI2 = "rssi2";
	public final int[] rssi2 = {-83, -80, -73, -60};

	/** RSSI thresholds for 5 GHz band (dBm) */
	public static final String KEY_RSSI5 = "rssi5";
	public final int[] rssi5 = {-80, -77, -70, -57};

	/** RSSI thresholds for 6 GHz band (dBm) */
	public static final String KEY_RSSI6 = "rssi6";
	public final int[] rssi6 = {-80, -77, -70, -57};

	/** Guidelines based on packet rates (packets/sec) */
	public static final String KEY_PPS = "pps";
	public final int[] pps = {0, 1, 100};

	/** Number of seconds for RSSI forecast */
	public static final String KEY_HORIZON = "horizon";
	public static final int MIN_HORIZON = -9;
	public static final int MAX_HORIZON = 60;
	public int horizon = 15;

	/** Number 0-10 influencing requests for network unreachability detection */
	public static final String KEY_NUD = "nud";
	public static final int MIN_NUD = 0;
	public static final int MAX_NUD = 10;
	public int nud = 8;

	/** Experiment identifier */
	public static final String KEY_EXPID = "expid";
	public static final int MIN_EXPID = 0;
	public static final int MAX_EXPID = Integer.MAX_VALUE;
	public int expid = 0;

	/** CandidateScorer parameters */
	public int throughputBonusNumerator = 120;
	public int throughputBonusDenominator = 433;
	public int throughputBonusLimit = 200;
	public int savedNetworkBonus = 500;
	public int unmeteredNetworkBonus = 1000;
	public int currentNetworkBonusMin = 20;
	public int currentNetworkBonusPercent = 20;
	public int secureNetworkBonus = 40;
	public int lastSelectionMinutes = 480;
	public int estimateRssiErrorMargin = 5;
	public static final int MIN_MINUTES = 1;
	public static final int MAX_MINUTES = Integer.MAX_VALUE / (60 * 1000);

	Values() {
	}

	Values(Values source) {
	for (int i = 0; i < rssi2.length; i++) {
	rssi2[i] = source.rssi2[i];
	}
	for (int i = 0; i < rssi5.length; i++) {
	rssi5[i] = source.rssi5[i];
	}
	for (int i = 0; i < rssi6.length; i++) {
	rssi6[i] = source.rssi6[i];
	}
	for (int i = 0; i < pps.length; i++) {
	pps[i] = source.pps[i];
	}
	horizon = source.horizon;
	nud = source.nud;
	expid = source.expid;
	}

	public void validate() throws IllegalArgumentException {
	validateRssiArray(rssi2);
	validateRssiArray(rssi5);
	validateRssiArray(rssi6);
	validateOrderedNonNegativeArray(pps);
	validateRange(horizon, MIN_HORIZON, MAX_HORIZON);
	validateRange(nud, MIN_NUD, MAX_NUD);
	validateRange(expid, MIN_EXPID, MAX_EXPID);
	validateRange(lastSelectionMinutes, MIN_MINUTES, MAX_MINUTES);
	}

	private void validateRssiArray(int[] rssi) throws IllegalArgumentException {
	int low = WifiInfo.MIN_RSSI;
	int high = Math.min(WifiInfo.MAX_RSSI, -1); // Stricter than Wifiinfo
	for (int i = 0; i < rssi.length; i++) {
	validateRange(rssi[i], low, high);
	low = rssi[i];
	}
	}

	private void validateRange(int k, int low, int high) throws IllegalArgumentException {
	if (k < low \|\| k > high) {
	throw new IllegalArgumentException();
	}
	}

	private void validateOrderedNonNegativeArray(int[] a) throws IllegalArgumentException {
	int low = 0;
	for (int i = 0; i < a.length; i++) {
	if (a[i] < low) {
	throw new IllegalArgumentException();
	}
	low = a[i];
	}
	}

	public void parseString(String kvList) throws IllegalArgumentException {
	KeyValueListParser parser = new KeyValueListParser(',');
	parser.setString(kvList);
	if (parser.size() != ("" + kvList).split(",").length) {
	throw new IllegalArgumentException("dup keys");
	}
	updateIntArray(rssi2, parser, KEY_RSSI2);
	updateIntArray(rssi5, parser, KEY_RSSI5);
	updateIntArray(rssi6, parser, KEY_RSSI6);
	updateIntArray(pps, parser, KEY_PPS);
	horizon = updateInt(parser, KEY_HORIZON, horizon);
	nud = updateInt(parser, KEY_NUD, nud);
	expid = updateInt(parser, KEY_EXPID, expid);
	}

	private int updateInt(KeyValueListParser parser, String key, int defaultValue)
	throws IllegalArgumentException {
	String value = parser.getString(key, null);
	if (value == null) return defaultValue;
	try {
	return Integer.parseInt(value);
	} catch (NumberFormatException e) {
	throw new IllegalArgumentException();
	}
	}

	private void updateIntArray(final int[] dest, KeyValueListParser parser, String key)
	throws IllegalArgumentException {
	if (parser.getString(key, null) == null) return;
	int[] ints = parser.getIntArray(key, null);
	if (ints == null) throw new IllegalArgumentException();
	if (ints.length != dest.length) throw new IllegalArgumentException();
	for (int i = 0; i < dest.length; i++) {
	dest[i] = ints[i];
	}
	}

	@Override
	public String toString() {
	StringBuilder sb = new StringBuilder();
	appendKey(sb, KEY_RSSI2);
	appendInts(sb, rssi2);
	appendKey(sb, KEY_RSSI5);
	appendInts(sb, rssi5);
	appendKey(sb, KEY_RSSI6);
	appendInts(sb, rssi6);
	appendKey(sb, KEY_PPS);
	appendInts(sb, pps);
	appendKey(sb, KEY_HORIZON);
	sb.append(horizon);
	appendKey(sb, KEY_NUD);
	sb.append(nud);
	appendKey(sb, KEY_EXPID);
	sb.append(expid);
	return sb.toString();
	}

	private void appendKey(StringBuilder sb, String key) {
	if (sb.length() != 0) sb.append(",");
	sb.append(key).append("=");
	}

	private void appendInts(StringBuilder sb, final int[] a) {
	final int n = a.length;
	for (int i = 0; i < n; i++) {
	if (i > 0) sb.append(":");
	sb.append(a[i]);
	}
	}
	}

	@NonNull private Values mVal = null;

	@VisibleForTesting
	public ScoringParams() {
	mContext = null;
	mVal = new Values();
	}

	public ScoringParams(Context context) {
	mContext = context;
	}

	private void loadResources(Context context) {
	if (mVal != null) return;
	mVal = new Values();
	mVal.rssi2[EXIT] = context.getResources().getInteger(
	R.integer.config_wifi_framework_wifi_score_bad_rssi_threshold_24GHz);
	mVal.rssi2[ENTRY] = context.getResources().getInteger(
	R.integer.config_wifi_framework_wifi_score_entry_rssi_threshold_24GHz);
	mVal.rssi2[SUFFICIENT] = context.getResources().getInteger(
	R.integer.config_wifi_framework_wifi_score_low_rssi_threshold_24GHz);
	mVal.rssi2[GOOD] = context.getResources().getInteger(
	R.integer.config_wifi_framework_wifi_score_good_rssi_threshold_24GHz);
	mVal.rssi5[EXIT] = context.getResources().getInteger(
	R.integer.config_wifi_framework_wifi_score_bad_rssi_threshold_5GHz);
	mVal.rssi5[ENTRY] = context.getResources().getInteger(
	R.integer.config_wifi_framework_wifi_score_entry_rssi_threshold_5GHz);
	mVal.rssi5[SUFFICIENT] = context.getResources().getInteger(
	R.integer.config_wifi_framework_wifi_score_low_rssi_threshold_5GHz);
	mVal.rssi5[GOOD] = context.getResources().getInteger(
	R.integer.config_wifi_framework_wifi_score_good_rssi_threshold_5GHz);
	mVal.rssi6[EXIT] = context.getResources().getInteger(
	R.integer.config_wifiFrameworkScoreBadRssiThreshold6ghz);
	mVal.rssi6[ENTRY] = context.getResources().getInteger(
	R.integer.config_wifiFrameworkScoreEntryRssiThreshold6ghz);
	mVal.rssi6[SUFFICIENT] = context.getResources().getInteger(
	R.integer.config_wifiFrameworkScoreLowRssiThreshold6ghz);
	mVal.rssi6[GOOD] = context.getResources().getInteger(
	R.integer.config_wifiFrameworkScoreGoodRssiThreshold6ghz);
	mVal.throughputBonusNumerator = context.getResources().getInteger(
	R.integer.config_wifiFrameworkThroughputBonusNumerator);
	mVal.throughputBonusDenominator = context.getResources().getInteger(
	R.integer.config_wifiFrameworkThroughputBonusDenominator);
	mVal.throughputBonusLimit = context.getResources().getInteger(
	R.integer.config_wifiFrameworkThroughputBonusLimit);
	mVal.savedNetworkBonus = context.getResources().getInteger(
	R.integer.config_wifiFrameworkSavedNetworkBonus);
	mVal.unmeteredNetworkBonus = context.getResources().getInteger(
	R.integer.config_wifiFrameworkUnmeteredNetworkBonus);
	mVal.currentNetworkBonusMin = context.getResources().getInteger(
	R.integer.config_wifiFrameworkCurrentNetworkBonusMin);
	mVal.currentNetworkBonusPercent = context.getResources().getInteger(
	R.integer.config_wifiFrameworkCurrentNetworkBonusPercent);
	mVal.secureNetworkBonus = context.getResources().getInteger(
	R.integer.config_wifiFrameworkSecureNetworkBonus);
	mVal.lastSelectionMinutes = context.getResources().getInteger(
	R.integer.config_wifiFrameworkLastSelectionMinutes);
	mVal.estimateRssiErrorMargin = context.getResources().getInteger(
	R.integer.config_wifiEstimateRssiErrorMarginDb);
	mVal.pps[ACTIVE_TRAFFIC] = context.getResources().getInteger(
	R.integer.config_wifiFrameworkMinPacketPerSecondActiveTraffic);
	mVal.pps[HIGH_TRAFFIC] = context.getResources().getInteger(
	R.integer.config_wifiFrameworkMinPacketPerSecondHighTraffic);
	try {
	mVal.validate();
	} catch (IllegalArgumentException e) {
	Log.wtf(TAG, "Inconsistent config_wifi_framework_ resources: " + this, e);
	}
	}

	private static final String COMMA_KEY_VAL_STAR = "^(,[A-Za-z_][A-Za-z0-9_]=[0-9.:+-]+)$";

	/**
	* Updates the parameters from the given parameter string.
	* If any errors are detected, no change is made.
	* @param kvList is a comma-separated key=value list.
	* @return true for success
	*/
	@VisibleForTesting
	public boolean update(String kvList) {
	if (kvList == null \|\| "".equals(kvList)) {
	return true;
	}
	if (!("," + kvList).matches(COMMA_KEY_VAL_STAR)) {
	return false;
	}
	loadResources(mContext);
	Values v = new Values(mVal);
	try {
	v.parseString(kvList);
	v.validate();
	mVal = v;
	return true;
	} catch (IllegalArgumentException e) {
	return false;
	}
	}

	/**
	* Sanitize a string to make it safe for printing.
	* @param params is the untrusted string
	* @return string with questionable characters replaced with question marks
	*/
	public String sanitize(String params) {
	if (params == null) return "";
	String printable = params.replaceAll("[^A-Za-z_0-9=,:.+-]", "?");
	if (printable.length() > 100) {
	printable = printable.substring(0, 98) + "...";
	}
	return printable;
	}

	/**
	* Returns the RSSI value at which the connection is deemed to be unusable,
	* in the absence of other indications.
	*/
	public int getExitRssi(int frequencyMegaHertz) {
	return getRssiArray(frequencyMegaHertz)[EXIT];
	}

	/**
	* Returns the minimum scan RSSI for making a connection attempt.
	*/
	public int getEntryRssi(int frequencyMegaHertz) {
	return getRssiArray(frequencyMegaHertz)[ENTRY];
	}

	/**
	* Returns a connected RSSI value that indicates the connection is
	* good enough that we needn't scan for alternatives.
	*/
	public int getSufficientRssi(int frequencyMegaHertz) {
	return getRssiArray(frequencyMegaHertz)[SUFFICIENT];
	}

	/**
	* Returns a connected RSSI value that indicates a good connection.
	*/
	public int getGoodRssi(int frequencyMegaHertz) {
	return getRssiArray(frequencyMegaHertz)[GOOD];
	}

	/**
	* Returns the number of seconds to use for rssi forecast.
	*/
	public int getHorizonSeconds() {
	loadResources(mContext);
	return mVal.horizon;
	}

	/**
	* Returns a packet rate that should be considered acceptable for staying on wifi,
	* no matter how bad the RSSI gets (packets per second).
	*/
	public int getYippeeSkippyPacketsPerSecond() {
	loadResources(mContext);
	return mVal.pps[HIGH_TRAFFIC];
	}

	/**
	* Returns a packet rate that should be considered acceptable to skip scan or network selection
	*/
	public int getActiveTrafficPacketsPerSecond() {
	loadResources(mContext);
	return mVal.pps[ACTIVE_TRAFFIC];
	}

	/**
	* Returns a number between 0 and 10 inclusive that indicates
	* how aggressive to be about asking for IP configuration checks
	* (also known as Network Unreachabilty Detection, or NUD).
	*
	* 0 - no nud checks requested by scorer (framework still checks after roam)
	* 1 - check when score becomes very low
	* ...
	* 10 - check when score first breaches threshold, and again as it gets worse
	*
	*/
	public int getNudKnob() {
	loadResources(mContext);
	return mVal.nud;
	}

	/**
	* Returns the estimate rssi error margin to account minor differences in the environment
	* and the device's orientation.
	*
	*/
	public int getEstimateRssiErrorMargin() {
	return mVal.estimateRssiErrorMargin;
	}

	/**
	*/
	public int getThroughputBonusNumerator() {
	return mVal.throughputBonusNumerator;
	}

	/**
	*/
	public int getThroughputBonusDenominator() {
	return mVal.throughputBonusDenominator;
	}

	/*
	* Returns the maximum bonus for the network selection candidate score
	* for the contribution of the selected score.
	*/
	public int getThroughputBonusLimit() {
	return mVal.throughputBonusLimit;
	}

	/*
	* Returns the bonus for the network selection candidate score
	* for a saved network (i.e., not a suggestion).
	*/
	public int getSavedNetworkBonus() {
	return mVal.savedNetworkBonus;
	}

	/*
	* Returns the bonus for the network selection candidate score
	* for an unmetered network.
	*/
	public int getUnmeteredNetworkBonus() {
	return mVal.unmeteredNetworkBonus;
	}

	/*
	* Returns the minimum bonus for the network selection candidate score
	* for the currently connected network.
	*/
	public int getCurrentNetworkBonusMin() {
	return mVal.currentNetworkBonusMin;
	}

	/*
	* Returns the percentage bonus for the network selection candidate score
	* for the currently connected network. The percent value is applied to rssi score and
	* throughput score;
	*/
	public int getCurrentNetworkBonusPercent() {
	return mVal.currentNetworkBonusPercent;
	}

	/*
	* Returns the bonus for the network selection candidate score
	* for a secure network.
	*/
	public int getSecureNetworkBonus() {
	return mVal.secureNetworkBonus;
	}

	/*
	* Returns the duration in minutes for a recently selected network
	* to be strongly favored.
	*/
	public int getLastSelectionMinutes() {
	return mVal.lastSelectionMinutes;
	}

	/**
	* Returns the experiment identifier.
	*
	* This value may be used to tag a set of experimental settings.
	*/
	public int getExperimentIdentifier() {
	loadResources(mContext);
	return mVal.expid;
	}

	private int[] getRssiArray(int frequency) {
	loadResources(mContext);
	if (ScanResult.is24GHz(frequency)) {
	return mVal.rssi2;
	} else if (ScanResult.is5GHz(frequency)) {
	return mVal.rssi5;
	} else if (ScanResult.is6GHz(frequency)) {
	return mVal.rssi6;
	}
	// Invalid frequency use
	Log.e(TAG, "Invalid frequency(" + frequency + "), using 5G as default rssi array");
	return mVal.rssi5;
	}

	@Override
	public String toString() {
	loadResources(mContext);
	return mVal.toString();
	}
	}