/*
 * Copyright (C) 2009 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.providers.contacts;

import com.android.providers.contacts.ContactMatcher.MatchScore;
import com.android.providers.contacts.ContactsDatabaseHelper.AggregatedPresenceColumns;
import com.android.providers.contacts.ContactsDatabaseHelper.ContactsColumns;
import com.android.providers.contacts.ContactsDatabaseHelper.DataColumns;
import com.android.providers.contacts.ContactsDatabaseHelper.NameLookupColumns;
import com.android.providers.contacts.ContactsDatabaseHelper.NameLookupType;
import com.android.providers.contacts.ContactsDatabaseHelper.PhoneLookupColumns;
import com.android.providers.contacts.ContactsDatabaseHelper.PresenceColumns;
import com.android.providers.contacts.ContactsDatabaseHelper.RawContactsColumns;
import com.android.providers.contacts.ContactsDatabaseHelper.Tables;

import android.content.ContentValues;
import android.database.Cursor;
import android.database.DatabaseUtils;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteQueryBuilder;
import android.database.sqlite.SQLiteStatement;
import android.net.Uri;
import android.provider.ContactsContract.AggregationExceptions;
import android.provider.ContactsContract.Contacts;
import android.provider.ContactsContract.Data;
import android.provider.ContactsContract.DisplayNameSources;
import android.provider.ContactsContract.RawContacts;
import android.provider.ContactsContract.StatusUpdates;
import android.provider.ContactsContract.CommonDataKinds.Email;
import android.provider.ContactsContract.CommonDataKinds.Phone;
import android.provider.ContactsContract.CommonDataKinds.Photo;
import android.text.TextUtils;
import android.util.EventLog;
import android.util.Log;

import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;


/**
 * ContactAggregator deals with aggregating contact information coming from different sources.
 * Two John Doe contacts from two disjoint sources are presumed to be the same
 * person unless the user declares otherwise.
 */
public class ContactAggregator {

    private static final String TAG = "ContactAggregator";

    private static final boolean VERBOSE_LOGGING = Log.isLoggable(TAG, Log.VERBOSE);

    private static final String STRUCTURED_NAME_BASED_LOOKUP_SQL =
            NameLookupColumns.NAME_TYPE + " IN ("
                    + NameLookupType.NAME_EXACT + ","
                    + NameLookupType.NAME_VARIANT + ","
                    + NameLookupType.NAME_COLLATION_KEY + ")";

    // From system/core/logcat/event-log-tags
    // aggregator [time, count] will be logged for each aggregator cycle.
    // For the query (as opposed to the merge), count will be negative
    public static final int LOG_SYNC_CONTACTS_AGGREGATION = 2747;

    // If we encounter more than this many contacts with matching names, aggregate only this many
    private static final int PRIMARY_HIT_LIMIT = 15;
    private static final String PRIMARY_HIT_LIMIT_STRING = String.valueOf(PRIMARY_HIT_LIMIT);

    // If we encounter more than this many contacts with matching phone number or email,
    // don't attempt to aggregate - this is likely an error or a shared corporate data element.
    private static final int SECONDARY_HIT_LIMIT = 20;
    private static final String SECONDARY_HIT_LIMIT_STRING = String.valueOf(SECONDARY_HIT_LIMIT);

    // If we encounter more than this many contacts with matching name during aggregation
    // suggestion lookup, ignore the remaining results.
    private static final int FIRST_LETTER_SUGGESTION_HIT_LIMIT = 100;

    private final ContactsProvider2 mContactsProvider;
    private final ContactsDatabaseHelper mDbHelper;
    private PhotoPriorityResolver mPhotoPriorityResolver;
    private boolean mEnabled = true;

    /** Precompiled sql statement for setting an aggregated presence */
    private SQLiteStatement mAggregatedPresenceReplace;
    private SQLiteStatement mPresenceContactIdUpdate;
    private SQLiteStatement mRawContactCountQuery;
    private SQLiteStatement mContactDelete;
    private SQLiteStatement mAggregatedPresenceDelete;
    private SQLiteStatement mMarkForAggregation;
    private SQLiteStatement mPhotoIdUpdate;
    private SQLiteStatement mDisplayNameUpdate;
    private SQLiteStatement mHasPhoneNumberUpdate;
    private SQLiteStatement mLookupKeyUpdate;
    private SQLiteStatement mStarredUpdate;
    private SQLiteStatement mContactIdAndMarkAggregatedUpdate;
    private SQLiteStatement mContactIdUpdate;
    private SQLiteStatement mMarkAggregatedUpdate;
    private SQLiteStatement mContactUpdate;
    private SQLiteStatement mContactInsert;

    private HashMap<Long, Integer> mRawContactsMarkedForAggregation = new HashMap<Long, Integer>();

    private String[] mSelectionArgs1 = new String[1];
    private String[] mSelectionArgs2 = new String[2];
    private String[] mSelectionArgs3 = new String[3];
    private long mMimeTypeIdEmail;
    private long mMimeTypeIdPhoto;
    private long mMimeTypeIdPhone;
    private String mRawContactsQueryByRawContactId;
    private String mRawContactsQueryByContactId;
    private StringBuilder mSb = new StringBuilder();
    private MatchCandidateList mCandidates = new MatchCandidateList();
    private ContactMatcher mMatcher = new ContactMatcher();
    private ContentValues mValues = new ContentValues();
    private DisplayNameCandidate mDisplayNameCandidate = new DisplayNameCandidate();

    /**
     * Captures a potential match for a given name. The matching algorithm
     * constructs a bunch of NameMatchCandidate objects for various potential matches
     * and then executes the search in bulk.
     */
    private static class NameMatchCandidate {
        String mName;
        int mLookupType;

        public NameMatchCandidate(String name, int nameLookupType) {
            mName = name;
            mLookupType = nameLookupType;
        }
    }

    /**
     * A list of {@link NameMatchCandidate} that keeps its elements even when the list is
     * truncated. This is done for optimization purposes to avoid excessive object allocation.
     */
    private static class MatchCandidateList {
        private final ArrayList<NameMatchCandidate> mList = new ArrayList<NameMatchCandidate>();
        private int mCount;

        /**
         * Adds a {@link NameMatchCandidate} element or updates the next one if it already exists.
         */
        public void add(String name, int nameLookupType) {
            if (mCount >= mList.size()) {
                mList.add(new NameMatchCandidate(name, nameLookupType));
            } else {
                NameMatchCandidate candidate = mList.get(mCount);
                candidate.mName = name;
                candidate.mLookupType = nameLookupType;
            }
            mCount++;
        }

        public void clear() {
            mCount = 0;
        }
    }

    /**
     * A convenience class used in the algorithm that figures out which of available
     * display names to use for an aggregate contact.
     */
    private static class DisplayNameCandidate {
        long rawContactId;
        String displayName;
        int displayNameSource;
        boolean verified;
        boolean writableAccount;

        public DisplayNameCandidate() {
            clear();
        }

        public void clear() {
            rawContactId = -1;
            displayName = null;
            displayNameSource = DisplayNameSources.UNDEFINED;
            verified = false;
            writableAccount = false;
        }
    }

    /**
     * Constructor.
     */
    public ContactAggregator(ContactsProvider2 contactsProvider,
            ContactsDatabaseHelper contactsDatabaseHelper,
            PhotoPriorityResolver photoPriorityResolver) {
        mContactsProvider = contactsProvider;
        mDbHelper = contactsDatabaseHelper;
        mPhotoPriorityResolver = photoPriorityResolver;

        SQLiteDatabase db = mDbHelper.getReadableDatabase();

        // Since we have no way of determining which custom status was set last,
        // we'll just pick one randomly.  We are using MAX as an approximation of randomness
        mAggregatedPresenceReplace = db.compileStatement(
                "INSERT OR REPLACE INTO " + Tables.AGGREGATED_PRESENCE + "("
                        + AggregatedPresenceColumns.CONTACT_ID + ", "
                        + StatusUpdates.PRESENCE_STATUS
                + ") SELECT ?, MAX(" + StatusUpdates.PRESENCE_STATUS + ") "
                        + " FROM " + Tables.PRESENCE
                        + " WHERE " + PresenceColumns.CONTACT_ID + "=?");

        mRawContactCountQuery = db.compileStatement(
                "SELECT COUNT(" + RawContacts._ID + ")" +
                " FROM " + Tables.RAW_CONTACTS +
                " WHERE " + RawContacts.CONTACT_ID + "=?"
                        + " AND " + RawContacts._ID + "<>?");

        mContactDelete = db.compileStatement(
                "DELETE FROM " + Tables.CONTACTS +
                " WHERE " + Contacts._ID + "=?");

        mAggregatedPresenceDelete = db.compileStatement(
                "DELETE FROM " + Tables.AGGREGATED_PRESENCE +
                " WHERE " + AggregatedPresenceColumns.CONTACT_ID + "=?");

        mMarkForAggregation = db.compileStatement(
                "UPDATE " + Tables.RAW_CONTACTS +
                " SET " + RawContactsColumns.AGGREGATION_NEEDED + "=1" +
                " WHERE " + RawContacts._ID + "=?"
                        + " AND " + RawContactsColumns.AGGREGATION_NEEDED + "=0");

        mPhotoIdUpdate = db.compileStatement(
                "UPDATE " + Tables.CONTACTS +
                " SET " + Contacts.PHOTO_ID + "=? " +
                " WHERE " + Contacts._ID + "=?");

        mDisplayNameUpdate = db.compileStatement(
                "UPDATE " + Tables.CONTACTS +
                " SET " + Contacts.NAME_RAW_CONTACT_ID + "=? " +
                " WHERE " + Contacts._ID + "=?");

        mLookupKeyUpdate = db.compileStatement(
                "UPDATE " + Tables.CONTACTS +
                " SET " + Contacts.LOOKUP_KEY + "=? " +
                " WHERE " + Contacts._ID + "=?");

        mHasPhoneNumberUpdate = db.compileStatement(
                "UPDATE " + Tables.CONTACTS +
                " SET " + Contacts.HAS_PHONE_NUMBER + "="
                        + "(SELECT (CASE WHEN COUNT(*)=0 THEN 0 ELSE 1 END)"
                        + " FROM " + Tables.DATA_JOIN_RAW_CONTACTS
                        + " WHERE " + DataColumns.MIMETYPE_ID + "=?"
                                + " AND " + Phone.NUMBER + " NOT NULL"
                                + " AND " + RawContacts.CONTACT_ID + "=?)" +
                " WHERE " + Contacts._ID + "=?");

        mStarredUpdate = db.compileStatement("UPDATE " + Tables.CONTACTS + " SET "
                + Contacts.STARRED + "=(SELECT (CASE WHEN COUNT(" + RawContacts.STARRED
                + ")=0 THEN 0 ELSE 1 END) FROM " + Tables.RAW_CONTACTS + " WHERE "
                + RawContacts.CONTACT_ID + "=" + ContactsColumns.CONCRETE_ID + " AND "
                + RawContacts.STARRED + "=1)" + " WHERE " + Contacts._ID + "=?");

        mContactIdAndMarkAggregatedUpdate = db.compileStatement(
                "UPDATE " + Tables.RAW_CONTACTS +
                " SET " + RawContacts.CONTACT_ID + "=?, "
                        + RawContactsColumns.AGGREGATION_NEEDED + "=0" +
                " WHERE " + RawContacts._ID + "=?");

        mContactIdUpdate = db.compileStatement(
                "UPDATE " + Tables.RAW_CONTACTS +
                " SET " + RawContacts.CONTACT_ID + "=?" +
                " WHERE " + RawContacts._ID + "=?");

        mMarkAggregatedUpdate = db.compileStatement(
                "UPDATE " + Tables.RAW_CONTACTS +
                " SET " + RawContactsColumns.AGGREGATION_NEEDED + "=0" +
                " WHERE " + RawContacts._ID + "=?");

        mPresenceContactIdUpdate = db.compileStatement(
                "UPDATE " + Tables.PRESENCE +
                " SET " + PresenceColumns.CONTACT_ID + "=?" +
                " WHERE " + PresenceColumns.RAW_CONTACT_ID + "=?");

        mContactUpdate = db.compileStatement(ContactReplaceSqlStatement.UPDATE_SQL);
        mContactInsert = db.compileStatement(ContactReplaceSqlStatement.INSERT_SQL);

        mMimeTypeIdEmail = mDbHelper.getMimeTypeId(Email.CONTENT_ITEM_TYPE);
        mMimeTypeIdPhoto = mDbHelper.getMimeTypeId(Photo.CONTENT_ITEM_TYPE);
        mMimeTypeIdPhone = mDbHelper.getMimeTypeId(Phone.CONTENT_ITEM_TYPE);

        // Query used to retrieve data from raw contacts to populate the corresponding aggregate
        mRawContactsQueryByRawContactId = String.format(
                RawContactsQuery.SQL_FORMAT_BY_RAW_CONTACT_ID,
                mMimeTypeIdPhoto, mMimeTypeIdPhone);

        mRawContactsQueryByContactId = String.format(
                RawContactsQuery.SQL_FORMAT_BY_CONTACT_ID,
                mMimeTypeIdPhoto, mMimeTypeIdPhone);
    }

    public void setEnabled(boolean enabled) {
        mEnabled = enabled;
    }

    public boolean isEnabled() {
        return mEnabled;
    }

    private interface AggregationQuery {
        String SQL =
                "SELECT " + RawContacts._ID + "," + RawContacts.CONTACT_ID +
                " FROM " + Tables.RAW_CONTACTS +
                " WHERE " + RawContacts._ID + " IN(";

        int _ID = 0;
        int CONTACT_ID = 1;
    }

    /**
     * Aggregate all raw contacts that were marked for aggregation in the current transaction.
     * Call just before committing the transaction.
     */
    public void aggregateInTransaction(SQLiteDatabase db) {
        int count = mRawContactsMarkedForAggregation.size();
        if (count == 0) {
            return;
        }

        long start = System.currentTimeMillis();
        if (VERBOSE_LOGGING) {
            Log.v(TAG, "Contact aggregation: " + count);
        }

        EventLog.writeEvent(LOG_SYNC_CONTACTS_AGGREGATION, start, -count);

        String selectionArgs[] = new String[count];

        int index = 0;
        mSb.setLength(0);
        mSb.append(AggregationQuery.SQL);
        for (long rawContactId : mRawContactsMarkedForAggregation.keySet()) {
            if (index > 0) {
                mSb.append(',');
            }
            mSb.append('?');
            selectionArgs[index++] = String.valueOf(rawContactId);
        }

        mSb.append(')');

        long rawContactIds[] = new long[count];
        long contactIds[] = new long[count];
        Cursor c = db.rawQuery(mSb.toString(), selectionArgs);
        try {
            count = c.getCount();
            index = 0;
            while (c.moveToNext()) {
                rawContactIds[index] = c.getLong(AggregationQuery._ID);
                contactIds[index] = c.getLong(AggregationQuery.CONTACT_ID);
                index++;
            }
        } finally {
            c.close();
        }

        for (int i = 0; i < count; i++) {
            aggregateContact(db, rawContactIds[i], contactIds[i], mCandidates, mMatcher, mValues);
        }

        long elapsedTime = System.currentTimeMillis() - start;
        EventLog.writeEvent(LOG_SYNC_CONTACTS_AGGREGATION, elapsedTime, count);

        if (VERBOSE_LOGGING) {
            String performance = count == 0 ? "" : ", " + (elapsedTime / count) + " ms per contact";
            Log.i(TAG, "Contact aggregation complete: " + count + performance);
        }
    }

    public void clearPendingAggregations() {
        mRawContactsMarkedForAggregation.clear();
    }

    public void markNewForAggregation(long rawContactId, int aggregationMode) {
        mRawContactsMarkedForAggregation.put(rawContactId, aggregationMode);
    }

    public void markForAggregation(long rawContactId, int aggregationMode, boolean force) {
        if (!force && mRawContactsMarkedForAggregation.containsKey(rawContactId)) {
            // As per ContactsContract documentation, default aggregation mode
            // does not override a previously set mode
            if (aggregationMode == RawContacts.AGGREGATION_MODE_DEFAULT) {
                aggregationMode = mRawContactsMarkedForAggregation.get(rawContactId);
            }
        } else {
            mMarkForAggregation.bindLong(1, rawContactId);
            mMarkForAggregation.execute();
        }

        mRawContactsMarkedForAggregation.put(rawContactId, aggregationMode);
    }

    /**
     * Creates a new contact based on the given raw contact.  Does not perform aggregation.
     */
    public void onRawContactInsert(SQLiteDatabase db, long rawContactId) {
        mSelectionArgs1[0] = String.valueOf(rawContactId);
        computeAggregateData(db, mRawContactsQueryByRawContactId, mSelectionArgs1, mContactInsert);
        long contactId = mContactInsert.executeInsert();
        setContactId(rawContactId, contactId);
        mDbHelper.updateContactVisible(contactId);
    }

    /**
     * Synchronously aggregate the specified contact assuming an open transaction.
     */
    public void aggregateContact(SQLiteDatabase db, long rawContactId, long currentContactId) {
        if (!mEnabled) {
            return;
        }

        MatchCandidateList candidates = new MatchCandidateList();
        ContactMatcher matcher = new ContactMatcher();
        ContentValues values = new ContentValues();

        aggregateContact(db, rawContactId, currentContactId, candidates, matcher, values);
    }

    public void updateAggregateData(long contactId) {
        if (!mEnabled) {
            return;
        }

        final SQLiteDatabase db = mDbHelper.getWritableDatabase();
        computeAggregateData(db, contactId, mContactUpdate);
        mContactUpdate.bindLong(ContactReplaceSqlStatement.CONTACT_ID, contactId);
        mContactUpdate.execute();

        mDbHelper.updateContactVisible(contactId);
        updateAggregatedPresence(contactId);
    }

    private void updateAggregatedPresence(long contactId) {
        mAggregatedPresenceReplace.bindLong(1, contactId);
        mAggregatedPresenceReplace.bindLong(2, contactId);
        mAggregatedPresenceReplace.execute();
    }

    /**
     * Given a specific raw contact, finds all matching aggregate contacts and chooses the one
     * with the highest match score.  If no such contact is found, creates a new contact.
     */
    private synchronized void aggregateContact(SQLiteDatabase db, long rawContactId,
            long currentContactId, MatchCandidateList candidates, ContactMatcher matcher,
            ContentValues values) {

        int aggregationMode = RawContacts.AGGREGATION_MODE_DEFAULT;

        Integer aggModeObject = mRawContactsMarkedForAggregation.remove(rawContactId);
        if (aggModeObject != null) {
            aggregationMode = aggModeObject;
        }

        long contactId = -1;

        if (aggregationMode == RawContacts.AGGREGATION_MODE_DEFAULT) {
            candidates.clear();
            matcher.clear();

            contactId = pickBestMatchBasedOnExceptions(db, rawContactId, matcher);
            if (contactId == -1) {
                contactId = pickBestMatchBasedOnData(db, rawContactId, candidates, matcher);
            }
        } else if (aggregationMode == RawContacts.AGGREGATION_MODE_DISABLED) {
            return;
        }

        long currentContactContentsCount = 0;

        if (currentContactId != 0) {
            mRawContactCountQuery.bindLong(1, currentContactId);
            mRawContactCountQuery.bindLong(2, rawContactId);
            currentContactContentsCount = mRawContactCountQuery.simpleQueryForLong();
        }

        // If there are no other raw contacts in the current aggregate, we might as well reuse it.
        // Also, if the aggregation mode is SUSPENDED, we must reuse the same aggregate.
        if (contactId == -1
                && currentContactId != 0
                && (currentContactContentsCount == 0
                        || aggregationMode == RawContacts.AGGREGATION_MODE_SUSPENDED)) {
            contactId = currentContactId;
        }

        if (contactId == currentContactId) {
            // Aggregation unchanged
            markAggregated(rawContactId);
        } else if (contactId == -1) {
            // Splitting an aggregate
            mSelectionArgs1[0] = String.valueOf(rawContactId);
            computeAggregateData(db, mRawContactsQueryByRawContactId, mSelectionArgs1,
                    mContactInsert);
            contactId = mContactInsert.executeInsert();
            setContactIdAndMarkAggregated(rawContactId, contactId);
            mDbHelper.updateContactVisible(contactId);

            setPresenceContactId(rawContactId, contactId);

            updateAggregatedPresence(contactId);

            if (currentContactContentsCount > 0) {
                updateAggregateData(currentContactId);
            }
        } else {
            // Joining with an existing aggregate
            if (currentContactContentsCount == 0) {
                // Delete a previous aggregate if it only contained this raw contact
                mContactDelete.bindLong(1, currentContactId);
                mContactDelete.execute();

                mAggregatedPresenceDelete.bindLong(1, currentContactId);
                mAggregatedPresenceDelete.execute();
            }

            setContactIdAndMarkAggregated(rawContactId, contactId);
            computeAggregateData(db, contactId, mContactUpdate);
            mContactUpdate.bindLong(ContactReplaceSqlStatement.CONTACT_ID, contactId);
            mContactUpdate.execute();
            mDbHelper.updateContactVisible(contactId);
            updateAggregatedPresence(contactId);
        }
    }

    /**
     * Updates the contact ID for the specified contact.
     */
    private void setContactId(long rawContactId, long contactId) {
        mContactIdUpdate.bindLong(1, contactId);
        mContactIdUpdate.bindLong(2, rawContactId);
        mContactIdUpdate.execute();
    }

    /**
     * Marks the specified raw contact ID as aggregated
     */
    private void markAggregated(long rawContactId) {
        mMarkAggregatedUpdate.bindLong(1, rawContactId);
        mMarkAggregatedUpdate.execute();
    }

    /**
     * Updates the contact ID for the specified contact and marks the raw contact as aggregated.
     */
    private void setContactIdAndMarkAggregated(long rawContactId, long contactId) {
        mContactIdAndMarkAggregatedUpdate.bindLong(1, contactId);
        mContactIdAndMarkAggregatedUpdate.bindLong(2, rawContactId);
        mContactIdAndMarkAggregatedUpdate.execute();
    }

    private void setPresenceContactId(long rawContactId, long contactId) {
        mPresenceContactIdUpdate.bindLong(1, contactId);
        mPresenceContactIdUpdate.bindLong(2, rawContactId);
        mPresenceContactIdUpdate.execute();
    }

    interface AggregateExceptionPrefetchQuery {
        String TABLE = Tables.AGGREGATION_EXCEPTIONS;

        String[] COLUMNS = {
            AggregationExceptions.RAW_CONTACT_ID1,
            AggregationExceptions.RAW_CONTACT_ID2,
        };

        int RAW_CONTACT_ID1 = 0;
        int RAW_CONTACT_ID2 = 1;
    }

    // A set of raw contact IDs for which there are aggregation exceptions
    private final HashSet<Long> mAggregationExceptionIds = new HashSet<Long>();
    private boolean mAggregationExceptionIdsValid;

    public void invalidateAggregationExceptionCache() {
        mAggregationExceptionIdsValid = false;
    }

    /**
     * Finds all raw contact IDs for which there are aggregation exceptions. The list of
     * ids is used as an optimization in aggregation: there is no point to run a query against
     * the agg_exceptions table if it is known that there are no records there for a given
     * raw contact ID.
     */
    private void prefetchAggregationExceptionIds(SQLiteDatabase db) {
        mAggregationExceptionIds.clear();
        final Cursor c = db.query(AggregateExceptionPrefetchQuery.TABLE,
                AggregateExceptionPrefetchQuery.COLUMNS,
                null, null, null, null, null);

        try {
            while (c.moveToNext()) {
                long rawContactId1 = c.getLong(AggregateExceptionPrefetchQuery.RAW_CONTACT_ID1);
                long rawContactId2 = c.getLong(AggregateExceptionPrefetchQuery.RAW_CONTACT_ID2);
                mAggregationExceptionIds.add(rawContactId1);
                mAggregationExceptionIds.add(rawContactId2);
            }
        } finally {
            c.close();
        }

        mAggregationExceptionIdsValid = true;
    }

    interface AggregateExceptionQuery {
        String TABLE = Tables.AGGREGATION_EXCEPTIONS
            + " JOIN raw_contacts raw_contacts1 "
                    + " ON (agg_exceptions.raw_contact_id1 = raw_contacts1._id) "
            + " JOIN raw_contacts raw_contacts2 "
                    + " ON (agg_exceptions.raw_contact_id2 = raw_contacts2._id) ";

        String[] COLUMNS = {
            AggregationExceptions.TYPE,
            AggregationExceptions.RAW_CONTACT_ID1,
            "raw_contacts1." + RawContacts.CONTACT_ID,
            "raw_contacts1." + RawContactsColumns.AGGREGATION_NEEDED,
            "raw_contacts2." + RawContacts.CONTACT_ID,
            "raw_contacts2." + RawContactsColumns.AGGREGATION_NEEDED,
        };

        int TYPE = 0;
        int RAW_CONTACT_ID1 = 1;
        int CONTACT_ID1 = 2;
        int AGGREGATION_NEEDED_1 = 3;
        int CONTACT_ID2 = 4;
        int AGGREGATION_NEEDED_2 = 5;
    }

    /**
     * Computes match scores based on exceptions entered by the user: always match and never match.
     * Returns the aggregate contact with the always match exception if any.
     */
    private long pickBestMatchBasedOnExceptions(SQLiteDatabase db, long rawContactId,
            ContactMatcher matcher) {
        if (!mAggregationExceptionIdsValid) {
            prefetchAggregationExceptionIds(db);
        }

        // If there are no aggregation exceptions involving this raw contact, there is no need to
        // run a query and we can just return -1, which stands for "nothing found"
        if (!mAggregationExceptionIds.contains(rawContactId)) {
            return -1;
        }

        final Cursor c = db.query(AggregateExceptionQuery.TABLE,
                AggregateExceptionQuery.COLUMNS,
                AggregationExceptions.RAW_CONTACT_ID1 + "=" + rawContactId
                        + " OR " + AggregationExceptions.RAW_CONTACT_ID2 + "=" + rawContactId,
                null, null, null, null);

        try {
            while (c.moveToNext()) {
                int type = c.getInt(AggregateExceptionQuery.TYPE);
                long rawContactId1 = c.getLong(AggregateExceptionQuery.RAW_CONTACT_ID1);
                long contactId = -1;
                if (rawContactId == rawContactId1) {
                    if (c.getInt(AggregateExceptionQuery.AGGREGATION_NEEDED_2) == 0
                            && !c.isNull(AggregateExceptionQuery.CONTACT_ID2)) {
                        contactId = c.getLong(AggregateExceptionQuery.CONTACT_ID2);
                    }
                } else {
                    if (c.getInt(AggregateExceptionQuery.AGGREGATION_NEEDED_1) == 0
                            && !c.isNull(AggregateExceptionQuery.CONTACT_ID1)) {
                        contactId = c.getLong(AggregateExceptionQuery.CONTACT_ID1);
                    }
                }
                if (contactId != -1) {
                    if (type == AggregationExceptions.TYPE_KEEP_TOGETHER) {
                        matcher.keepIn(contactId);
                    } else {
                        matcher.keepOut(contactId);
                    }
                }
            }
        } finally {
            c.close();
        }

        return matcher.pickBestMatch(ContactMatcher.MAX_SCORE);
    }

    /**
     * Picks the best matching contact based on matches between data elements.  It considers
     * name match to be primary and phone, email etc matches to be secondary.  A good primary
     * match triggers aggregation, while a good secondary match only triggers aggregation in
     * the absence of a strong primary mismatch.
     * <p>
     * Consider these examples:
     * <p>
     * John Doe with phone number 111-111-1111 and Jon Doe with phone number 111-111-1111 should
     * be aggregated (same number, similar names).
     * <p>
     * John Doe with phone number 111-111-1111 and Deborah Doe with phone number 111-111-1111 should
     * not be aggregated (same number, different names).
     */
    private long pickBestMatchBasedOnData(SQLiteDatabase db, long rawContactId,
            MatchCandidateList candidates, ContactMatcher matcher) {

        // Find good matches based on name alone
        long bestMatch = updateMatchScoresBasedOnDataMatches(db, rawContactId, candidates, matcher);
        if (bestMatch == -1) {
            // We haven't found a good match on name, see if we have any matches on phone, email etc
            bestMatch = pickBestMatchBasedOnSecondaryData(db, rawContactId, candidates, matcher);
        }

        return bestMatch;
    }


    /**
     * Picks the best matching contact based on secondary data matches.  The method loads
     * structured names for all candidate contacts and recomputes match scores using approximate
     * matching.
     */
    private long pickBestMatchBasedOnSecondaryData(SQLiteDatabase db,
            long rawContactId, MatchCandidateList candidates, ContactMatcher matcher) {
        List<Long> secondaryContactIds = matcher.prepareSecondaryMatchCandidates(
                ContactMatcher.SCORE_THRESHOLD_PRIMARY);
        if (secondaryContactIds == null || secondaryContactIds.size() > SECONDARY_HIT_LIMIT) {
            return -1;
        }

        loadNameMatchCandidates(db, rawContactId, candidates, true);

        mSb.setLength(0);
        mSb.append(RawContacts.CONTACT_ID).append(" IN (");
        for (int i = 0; i < secondaryContactIds.size(); i++) {
            if (i != 0) {
                mSb.append(',');
            }
            mSb.append(secondaryContactIds.get(i));
        }

        // We only want to compare structured names to structured names
        // at this stage, we need to ignore all other sources of name lookup data.
        mSb.append(") AND " + STRUCTURED_NAME_BASED_LOOKUP_SQL);

        matchAllCandidates(db, mSb.toString(), candidates, matcher,
                ContactMatcher.MATCHING_ALGORITHM_CONSERVATIVE, null);

        return matcher.pickBestMatch(ContactMatcher.SCORE_THRESHOLD_SECONDARY);
    }

    private interface NameLookupQuery {
        String TABLE = Tables.NAME_LOOKUP;

        String SELECTION = NameLookupColumns.RAW_CONTACT_ID + "=?";
        String SELECTION_STRUCTURED_NAME_BASED =
                SELECTION + " AND " + STRUCTURED_NAME_BASED_LOOKUP_SQL;

        String[] COLUMNS = new String[] {
                NameLookupColumns.NORMALIZED_NAME,
                NameLookupColumns.NAME_TYPE
        };

        int NORMALIZED_NAME = 0;
        int NAME_TYPE = 1;
    }

    private void loadNameMatchCandidates(SQLiteDatabase db, long rawContactId,
            MatchCandidateList candidates, boolean structuredNameBased) {
        candidates.clear();
        mSelectionArgs1[0] = String.valueOf(rawContactId);
        Cursor c = db.query(NameLookupQuery.TABLE, NameLookupQuery.COLUMNS,
                structuredNameBased
                        ? NameLookupQuery.SELECTION_STRUCTURED_NAME_BASED
                        : NameLookupQuery.SELECTION,
                mSelectionArgs1, null, null, null);
        try {
            while (c.moveToNext()) {
                String normalizedName = c.getString(NameLookupQuery.NORMALIZED_NAME);
                int type = c.getInt(NameLookupQuery.NAME_TYPE);
                candidates.add(normalizedName, type);
            }
        } finally {
            c.close();
        }
    }

    /**
     * Computes scores for contacts that have matching data rows.
     */
    private long updateMatchScoresBasedOnDataMatches(SQLiteDatabase db, long rawContactId,
            MatchCandidateList candidates, ContactMatcher matcher) {

        updateMatchScoresBasedOnNameMatches(db, rawContactId, matcher);
        long bestMatch = matcher.pickBestMatch(ContactMatcher.SCORE_THRESHOLD_PRIMARY);
        if (bestMatch != -1) {
            return bestMatch;
        }

        updateMatchScoresBasedOnEmailMatches(db, rawContactId, matcher);
        updateMatchScoresBasedOnPhoneMatches(db, rawContactId, matcher);

        return -1;
    }

    private interface NameLookupMatchQuery {
        String TABLE = Tables.NAME_LOOKUP + " nameA"
                + " JOIN " + Tables.NAME_LOOKUP + " nameB" +
                " ON (" + "nameA." + NameLookupColumns.NORMALIZED_NAME + "="
                        + "nameB." + NameLookupColumns.NORMALIZED_NAME + ")"
                + " JOIN " + Tables.RAW_CONTACTS +
                " ON (nameB." + NameLookupColumns.RAW_CONTACT_ID + " = "
                        + Tables.RAW_CONTACTS + "." + RawContacts._ID + ")";

        String SELECTION = "nameA." + NameLookupColumns.RAW_CONTACT_ID + "=?"
                + " AND " + RawContactsColumns.AGGREGATION_NEEDED + "=0";

        String[] COLUMNS = new String[] {
            RawContacts.CONTACT_ID,
            "nameA." + NameLookupColumns.NORMALIZED_NAME,
            "nameA." + NameLookupColumns.NAME_TYPE,
            "nameB." + NameLookupColumns.NAME_TYPE,
        };

        int CONTACT_ID = 0;
        int NAME = 1;
        int NAME_TYPE_A = 2;
        int NAME_TYPE_B = 3;
    }

    private void updateMatchScoresBasedOnNameMatches(SQLiteDatabase db, long rawContactId,
            ContactMatcher matcher) {
        mSelectionArgs1[0] = String.valueOf(rawContactId);
        Cursor c = db.query(NameLookupMatchQuery.TABLE, NameLookupMatchQuery.COLUMNS,
                NameLookupMatchQuery.SELECTION,
                mSelectionArgs1, null, null, null, PRIMARY_HIT_LIMIT_STRING);
        try {
            while (c.moveToNext()) {
                long contactId = c.getLong(NameLookupMatchQuery.CONTACT_ID);
                String name = c.getString(NameLookupMatchQuery.NAME);
                int nameTypeA = c.getInt(NameLookupMatchQuery.NAME_TYPE_A);
                int nameTypeB = c.getInt(NameLookupMatchQuery.NAME_TYPE_B);
                matcher.matchName(contactId, nameTypeA, name,
                        nameTypeB, name, ContactMatcher.MATCHING_ALGORITHM_EXACT);
                if (nameTypeA == NameLookupType.NICKNAME &&
                        nameTypeB == NameLookupType.NICKNAME) {
                    matcher.updateScoreWithNicknameMatch(contactId);
                }
            }
        } finally {
            c.close();
        }
    }

    private interface EmailLookupQuery {
        String TABLE = Tables.DATA + " dataA"
                + " JOIN " + Tables.DATA + " dataB" +
                " ON (" + "dataA." + Email.DATA + "=dataB." + Email.DATA + ")"
                + " JOIN " + Tables.RAW_CONTACTS +
                " ON (dataB." + Data.RAW_CONTACT_ID + " = "
                        + Tables.RAW_CONTACTS + "." + RawContacts._ID + ")";

        String SELECTION = "dataA." + Data.RAW_CONTACT_ID + "=?"
                + " AND dataA." + DataColumns.MIMETYPE_ID + "=?"
                + " AND dataA." + Email.DATA + " NOT NULL"
                + " AND dataB." + DataColumns.MIMETYPE_ID + "=?"
                + " AND " + RawContactsColumns.AGGREGATION_NEEDED + "=0";

        String[] COLUMNS = new String[] {
            RawContacts.CONTACT_ID
        };

        int CONTACT_ID = 0;
    }

    private void updateMatchScoresBasedOnEmailMatches(SQLiteDatabase db, long rawContactId,
            ContactMatcher matcher) {
        mSelectionArgs3[0] = String.valueOf(rawContactId);
        mSelectionArgs3[1] = mSelectionArgs3[2] = String.valueOf(mMimeTypeIdEmail);
        Cursor c = db.query(EmailLookupQuery.TABLE, EmailLookupQuery.COLUMNS,
                EmailLookupQuery.SELECTION,
                mSelectionArgs3, null, null, null, SECONDARY_HIT_LIMIT_STRING);
        try {
            while (c.moveToNext()) {
                long contactId = c.getLong(EmailLookupQuery.CONTACT_ID);
                matcher.updateScoreWithEmailMatch(contactId);
            }
        } finally {
            c.close();
        }
    }

    private interface PhoneLookupQuery {
        String TABLE = Tables.PHONE_LOOKUP + " phoneA"
                + " JOIN " + Tables.DATA + " dataA"
                + " ON (dataA." + Data._ID + "=phoneA." + PhoneLookupColumns.DATA_ID + ")"
                + " JOIN " + Tables.PHONE_LOOKUP + " phoneB"
                + " ON (phoneA." + PhoneLookupColumns.MIN_MATCH + "="
                        + "phoneB." + PhoneLookupColumns.MIN_MATCH + ")"
                + " JOIN " + Tables.DATA + " dataB"
                + " ON (dataB." + Data._ID + "=phoneB." + PhoneLookupColumns.DATA_ID + ")"
                + " JOIN " + Tables.RAW_CONTACTS
                + " ON (dataB." + Data.RAW_CONTACT_ID + " = "
                        + Tables.RAW_CONTACTS + "." + RawContacts._ID + ")";

        String SELECTION = "dataA." + Data.RAW_CONTACT_ID + "=?"
                + " AND PHONE_NUMBERS_EQUAL(dataA." + Phone.NUMBER + ", "
                        + "dataB." + Phone.NUMBER + ",?)"
                + " AND " + RawContactsColumns.AGGREGATION_NEEDED + "=0";

        String[] COLUMNS = new String[] {
            RawContacts.CONTACT_ID
        };

        int CONTACT_ID = 0;
    }

    private void updateMatchScoresBasedOnPhoneMatches(SQLiteDatabase db, long rawContactId,
            ContactMatcher matcher) {
        mSelectionArgs2[0] = String.valueOf(rawContactId);
        mSelectionArgs2[1] = mDbHelper.getUseStrictPhoneNumberComparisonParameter();
        Cursor c = db.query(PhoneLookupQuery.TABLE, PhoneLookupQuery.COLUMNS,
                PhoneLookupQuery.SELECTION,
                mSelectionArgs2, null, null, null, SECONDARY_HIT_LIMIT_STRING);
        try {
            while (c.moveToNext()) {
                long contactId = c.getLong(PhoneLookupQuery.CONTACT_ID);
                matcher.updateScoreWithPhoneNumberMatch(contactId);
            }
        } finally {
            c.close();
        }

    }

    /**
     * Loads name lookup rows for approximate name matching and updates match scores based on that
     * data.
     */
    private void lookupApproximateNameMatches(SQLiteDatabase db, MatchCandidateList candidates,
            ContactMatcher matcher) {
        HashSet<String> firstLetters = new HashSet<String>();
        for (int i = 0; i < candidates.mCount; i++) {
            final NameMatchCandidate candidate = candidates.mList.get(i);
            if (candidate.mName.length() >= 2) {
                String firstLetter = candidate.mName.substring(0, 2);
                if (!firstLetters.contains(firstLetter)) {
                    firstLetters.add(firstLetter);
                    final String selection = "(" + NameLookupColumns.NORMALIZED_NAME + " GLOB '"
                            + firstLetter + "*') AND "
                            + NameLookupColumns.NAME_TYPE + " IN("
                                    + NameLookupType.NAME_COLLATION_KEY + ","
                                    + NameLookupType.EMAIL_BASED_NICKNAME + ","
                                    + NameLookupType.NICKNAME + ")";
                    matchAllCandidates(db, selection, candidates, matcher,
                            ContactMatcher.MATCHING_ALGORITHM_APPROXIMATE,
                            String.valueOf(FIRST_LETTER_SUGGESTION_HIT_LIMIT));
                }
            }
        }
    }

    private interface ContactNameLookupQuery {
        String TABLE = Tables.NAME_LOOKUP_JOIN_RAW_CONTACTS;

        String[] COLUMNS = new String[] {
                RawContacts.CONTACT_ID,
                NameLookupColumns.NORMALIZED_NAME,
                NameLookupColumns.NAME_TYPE
        };

        int CONTACT_ID = 0;
        int NORMALIZED_NAME = 1;
        int NAME_TYPE = 2;
    }

    /**
     * Loads all candidate rows from the name lookup table and updates match scores based
     * on that data.
     */
    private void matchAllCandidates(SQLiteDatabase db, String selection,
            MatchCandidateList candidates, ContactMatcher matcher, int algorithm, String limit) {
        final Cursor c = db.query(ContactNameLookupQuery.TABLE, ContactNameLookupQuery.COLUMNS,
                selection, null, null, null, null, limit);

        try {
            while (c.moveToNext()) {
                Long contactId = c.getLong(ContactNameLookupQuery.CONTACT_ID);
                String name = c.getString(ContactNameLookupQuery.NORMALIZED_NAME);
                int nameType = c.getInt(ContactNameLookupQuery.NAME_TYPE);

                // Note the N^2 complexity of the following fragment. This is not a huge concern
                // since the number of candidates is very small and in general secondary hits
                // in the absence of primary hits are rare.
                for (int i = 0; i < candidates.mCount; i++) {
                    NameMatchCandidate candidate = candidates.mList.get(i);
                    matcher.matchName(contactId, candidate.mLookupType, candidate.mName,
                            nameType, name, algorithm);
                }
            }
        } finally {
            c.close();
        }
    }

    private interface RawContactsQuery {
        String SQL_FORMAT =
                "SELECT "
                        + RawContactsColumns.CONCRETE_ID + ","
                        + RawContactsColumns.DISPLAY_NAME + ","
                        + RawContactsColumns.DISPLAY_NAME_SOURCE + ","
                        + RawContacts.ACCOUNT_TYPE + ","
                        + RawContacts.ACCOUNT_NAME + ","
                        + RawContacts.SOURCE_ID + ","
                        + RawContacts.CUSTOM_RINGTONE + ","
                        + RawContacts.SEND_TO_VOICEMAIL + ","
                        + RawContacts.LAST_TIME_CONTACTED + ","
                        + RawContacts.TIMES_CONTACTED + ","
                        + RawContacts.STARRED + ","
                        + RawContacts.IS_RESTRICTED + ","
                        + RawContacts.NAME_VERIFIED + ","
                        + DataColumns.CONCRETE_ID + ","
                        + DataColumns.CONCRETE_MIMETYPE_ID + ","
                        + Data.IS_SUPER_PRIMARY +
                " FROM " + Tables.RAW_CONTACTS +
                " LEFT OUTER JOIN " + Tables.DATA +
                " ON (" + DataColumns.CONCRETE_RAW_CONTACT_ID + "=" + RawContactsColumns.CONCRETE_ID
                        + " AND ((" + DataColumns.MIMETYPE_ID + "=%d"
                                + " AND " + Photo.PHOTO + " NOT NULL)"
                        + " OR (" + DataColumns.MIMETYPE_ID + "=%d"
                                + " AND " + Phone.NUMBER + " NOT NULL)))";

        String SQL_FORMAT_BY_RAW_CONTACT_ID = SQL_FORMAT +
                " WHERE " + RawContactsColumns.CONCRETE_ID + "=?";

        String SQL_FORMAT_BY_CONTACT_ID = SQL_FORMAT +
                " WHERE " + RawContacts.CONTACT_ID + "=?"
                + " AND " + RawContacts.DELETED + "=0";

        int RAW_CONTACT_ID = 0;
        int DISPLAY_NAME = 1;
        int DISPLAY_NAME_SOURCE = 2;
        int ACCOUNT_TYPE = 3;
        int ACCOUNT_NAME = 4;
        int SOURCE_ID = 5;
        int CUSTOM_RINGTONE = 6;
        int SEND_TO_VOICEMAIL = 7;
        int LAST_TIME_CONTACTED = 8;
        int TIMES_CONTACTED = 9;
        int STARRED = 10;
        int IS_RESTRICTED = 11;
        int NAME_VERIFIED = 12;
        int DATA_ID = 13;
        int MIMETYPE_ID = 14;
        int IS_SUPER_PRIMARY = 15;
    }

    private interface ContactReplaceSqlStatement {
        String UPDATE_SQL =
                "UPDATE " + Tables.CONTACTS +
                " SET "
                        + Contacts.NAME_RAW_CONTACT_ID + "=?, "
                        + Contacts.PHOTO_ID + "=?, "
                        + Contacts.SEND_TO_VOICEMAIL + "=?, "
                        + Contacts.CUSTOM_RINGTONE + "=?, "
                        + Contacts.LAST_TIME_CONTACTED + "=?, "
                        + Contacts.TIMES_CONTACTED + "=?, "
                        + Contacts.STARRED + "=?, "
                        + Contacts.HAS_PHONE_NUMBER + "=?, "
                        + ContactsColumns.SINGLE_IS_RESTRICTED + "=?, "
                        + Contacts.LOOKUP_KEY + "=? " +
                " WHERE " + Contacts._ID + "=?";

        String INSERT_SQL =
                "INSERT INTO " + Tables.CONTACTS + " ("
                        + Contacts.NAME_RAW_CONTACT_ID + ", "
                        + Contacts.PHOTO_ID + ", "
                        + Contacts.SEND_TO_VOICEMAIL + ", "
                        + Contacts.CUSTOM_RINGTONE + ", "
                        + Contacts.LAST_TIME_CONTACTED + ", "
                        + Contacts.TIMES_CONTACTED + ", "
                        + Contacts.STARRED + ", "
                        + Contacts.HAS_PHONE_NUMBER + ", "
                        + ContactsColumns.SINGLE_IS_RESTRICTED + ", "
                        + Contacts.LOOKUP_KEY + ", "
                        + Contacts.IN_VISIBLE_GROUP + ") " +
                " VALUES (?,?,?,?,?,?,?,?,?,?,0)";

        int NAME_RAW_CONTACT_ID = 1;
        int PHOTO_ID = 2;
        int SEND_TO_VOICEMAIL = 3;
        int CUSTOM_RINGTONE = 4;
        int LAST_TIME_CONTACTED = 5;
        int TIMES_CONTACTED = 6;
        int STARRED = 7;
        int HAS_PHONE_NUMBER = 8;
        int SINGLE_IS_RESTRICTED = 9;
        int LOOKUP_KEY = 10;
        int CONTACT_ID = 11;
    }

    /**
     * Computes aggregate-level data for the specified aggregate contact ID.
     */
    private void computeAggregateData(SQLiteDatabase db, long contactId,
            SQLiteStatement statement) {
        mSelectionArgs1[0] = String.valueOf(contactId);
        computeAggregateData(db, mRawContactsQueryByContactId, mSelectionArgs1, statement);
    }

    /**
     * Computes aggregate-level data from constituent raw contacts.
     */
    private void computeAggregateData(final SQLiteDatabase db, String sql, String[] sqlArgs,
            SQLiteStatement statement) {
        long currentRawContactId = -1;
        long bestPhotoId = -1;
        boolean foundSuperPrimaryPhoto = false;
        int photoPriority = -1;
        int totalRowCount = 0;
        int contactSendToVoicemail = 0;
        String contactCustomRingtone = null;
        long contactLastTimeContacted = 0;
        int contactTimesContacted = 0;
        int contactStarred = 0;
        int singleIsRestricted = 1;
        int hasPhoneNumber = 0;

        mDisplayNameCandidate.clear();

        mSb.setLength(0);       // Lookup key
        Cursor c = db.rawQuery(sql, sqlArgs);
        try {
            while (c.moveToNext()) {
                long rawContactId = c.getLong(RawContactsQuery.RAW_CONTACT_ID);
                if (rawContactId != currentRawContactId) {
                    currentRawContactId = rawContactId;
                    totalRowCount++;

                    // Display name
                    String displayName = c.getString(RawContactsQuery.DISPLAY_NAME);
                    int displayNameSource = c.getInt(RawContactsQuery.DISPLAY_NAME_SOURCE);
                    int nameVerified = c.getInt(RawContactsQuery.NAME_VERIFIED);
                    String accountType = c.getString(RawContactsQuery.ACCOUNT_TYPE);
                    processDisplayNameCanditate(rawContactId, displayName, displayNameSource,
                            mContactsProvider.isWritableAccount(accountType), nameVerified != 0);


                    // Contact options
                    if (!c.isNull(RawContactsQuery.SEND_TO_VOICEMAIL)) {
                        boolean sendToVoicemail =
                                (c.getInt(RawContactsQuery.SEND_TO_VOICEMAIL) != 0);
                        if (sendToVoicemail) {
                            contactSendToVoicemail++;
                        }
                    }

                    if (contactCustomRingtone == null
                            && !c.isNull(RawContactsQuery.CUSTOM_RINGTONE)) {
                        contactCustomRingtone = c.getString(RawContactsQuery.CUSTOM_RINGTONE);
                    }

                    long lastTimeContacted = c.getLong(RawContactsQuery.LAST_TIME_CONTACTED);
                    if (lastTimeContacted > contactLastTimeContacted) {
                        contactLastTimeContacted = lastTimeContacted;
                    }

                    int timesContacted = c.getInt(RawContactsQuery.TIMES_CONTACTED);
                    if (timesContacted > contactTimesContacted) {
                        contactTimesContacted = timesContacted;
                    }

                    if (c.getInt(RawContactsQuery.STARRED) != 0) {
                        contactStarred = 1;
                    }

                    // Single restricted
                    if (totalRowCount > 1) {
                        // Not single
                        singleIsRestricted = 0;
                    } else {
                        int isRestricted = c.getInt(RawContactsQuery.IS_RESTRICTED);

                        if (isRestricted == 0) {
                            // Not restricted
                            singleIsRestricted = 0;
                        }
                    }

                    ContactLookupKey.appendToLookupKey(mSb,
                            c.getString(RawContactsQuery.ACCOUNT_TYPE),
                            c.getString(RawContactsQuery.ACCOUNT_NAME),
                            rawContactId,
                            c.getString(RawContactsQuery.SOURCE_ID),
                            displayName);
                }

                if (!c.isNull(RawContactsQuery.DATA_ID)) {
                    long dataId = c.getLong(RawContactsQuery.DATA_ID);
                    int mimetypeId = c.getInt(RawContactsQuery.MIMETYPE_ID);
                    boolean superPrimary = c.getInt(RawContactsQuery.IS_SUPER_PRIMARY) != 0;
                    if (mimetypeId == mMimeTypeIdPhoto) {
                        if (!foundSuperPrimaryPhoto) {
                            String accountType = c.getString(RawContactsQuery.ACCOUNT_TYPE);
                            int priority = mPhotoPriorityResolver.getPhotoPriority(accountType);
                            if (superPrimary || priority > photoPriority) {
                                photoPriority = priority;
                                bestPhotoId = dataId;
                                foundSuperPrimaryPhoto |= superPrimary;
                            }
                        }
                    } else if (mimetypeId == mMimeTypeIdPhone) {
                        hasPhoneNumber = 1;
                    }
                }
            }
        } finally {
            c.close();
        }

        statement.bindLong(ContactReplaceSqlStatement.NAME_RAW_CONTACT_ID,
                mDisplayNameCandidate.rawContactId);

        if (bestPhotoId != -1) {
            statement.bindLong(ContactReplaceSqlStatement.PHOTO_ID, bestPhotoId);
        } else {
            statement.bindNull(ContactReplaceSqlStatement.PHOTO_ID);
        }

        statement.bindLong(ContactReplaceSqlStatement.SEND_TO_VOICEMAIL,
                totalRowCount == contactSendToVoicemail ? 1 : 0);
        DatabaseUtils.bindObjectToProgram(statement, ContactReplaceSqlStatement.CUSTOM_RINGTONE,
                contactCustomRingtone);
        statement.bindLong(ContactReplaceSqlStatement.LAST_TIME_CONTACTED,
                contactLastTimeContacted);
        statement.bindLong(ContactReplaceSqlStatement.TIMES_CONTACTED,
                contactTimesContacted);
        statement.bindLong(ContactReplaceSqlStatement.STARRED,
                contactStarred);
        statement.bindLong(ContactReplaceSqlStatement.HAS_PHONE_NUMBER,
                hasPhoneNumber);
        statement.bindLong(ContactReplaceSqlStatement.SINGLE_IS_RESTRICTED,
                singleIsRestricted);
        statement.bindString(ContactReplaceSqlStatement.LOOKUP_KEY,
                Uri.encode(mSb.toString()));
    }

    /**
     * Uses the supplied values to determine if they represent a "better" display name
     * for the aggregate contact currently evaluated.  If so, it updates
     * {@link #mDisplayNameCandidate} with the new values.
     */
    private void processDisplayNameCanditate(long rawContactId, String displayName,
            int displayNameSource, boolean writableAccount, boolean verified) {

        boolean replace = false;
        if (mDisplayNameCandidate.rawContactId == -1) {
            // No previous values available
            replace = true;
        } else if (!TextUtils.isEmpty(displayName)) {
            if (!mDisplayNameCandidate.verified && verified) {
                // A verified name is better than any other name
                replace = true;
            } else if (mDisplayNameCandidate.verified == verified) {
                if (mDisplayNameCandidate.displayNameSource < displayNameSource) {
                    // New values come from an superior source, e.g. structured name vs phone number
                    replace = true;
                } else if (mDisplayNameCandidate.displayNameSource == displayNameSource) {
                    if (!mDisplayNameCandidate.writableAccount && writableAccount) {
                        replace = true;
                    } else if (mDisplayNameCandidate.writableAccount == writableAccount) {
                        if (NameNormalizer.compareComplexity(displayName,
                                mDisplayNameCandidate.displayName) > 0) {
                            // New name is more complex than the previously found one
                            replace = true;
                        }
                    }
                }
            }
        }

        if (replace) {
            mDisplayNameCandidate.rawContactId = rawContactId;
            mDisplayNameCandidate.displayName = displayName;
            mDisplayNameCandidate.displayNameSource = displayNameSource;
            mDisplayNameCandidate.verified = verified;
            mDisplayNameCandidate.writableAccount = writableAccount;
        }
    }

    private interface PhotoIdQuery {
        String[] COLUMNS = new String[] {
            RawContacts.ACCOUNT_TYPE,
            DataColumns.CONCRETE_ID,
            Data.IS_SUPER_PRIMARY,
        };

        int ACCOUNT_TYPE = 0;
        int DATA_ID = 1;
        int IS_SUPER_PRIMARY = 2;
    }

    public void updatePhotoId(SQLiteDatabase db, long rawContactId) {

        long contactId = mDbHelper.getContactId(rawContactId);
        if (contactId == 0) {
            return;
        }

        long bestPhotoId = -1;
        int photoPriority = -1;

        long photoMimeType = mDbHelper.getMimeTypeId(Photo.CONTENT_ITEM_TYPE);

        String tables = Tables.RAW_CONTACTS + " JOIN " + Tables.DATA + " ON("
                + DataColumns.CONCRETE_RAW_CONTACT_ID + "=" + RawContactsColumns.CONCRETE_ID
                + " AND (" + DataColumns.MIMETYPE_ID + "=" + photoMimeType + " AND "
                        + Photo.PHOTO + " NOT NULL))";

        mSelectionArgs1[0] = String.valueOf(contactId);
        final Cursor c = db.query(tables, PhotoIdQuery.COLUMNS,
                RawContacts.CONTACT_ID + "=?", mSelectionArgs1, null, null, null);
        try {
            while (c.moveToNext()) {
                long dataId = c.getLong(PhotoIdQuery.DATA_ID);
                boolean superprimary = c.getInt(PhotoIdQuery.IS_SUPER_PRIMARY) != 0;
                if (superprimary) {
                    bestPhotoId = dataId;
                    break;
                }

                String accountType = c.getString(PhotoIdQuery.ACCOUNT_TYPE);
                int priority = mPhotoPriorityResolver.getPhotoPriority(accountType);
                if (priority > photoPriority) {
                    photoPriority = priority;
                    bestPhotoId = dataId;
                }
            }
        } finally {
            c.close();
        }

        if (bestPhotoId == -1) {
            mPhotoIdUpdate.bindNull(1);
        } else {
            mPhotoIdUpdate.bindLong(1, bestPhotoId);
        }
        mPhotoIdUpdate.bindLong(2, contactId);
        mPhotoIdUpdate.execute();
    }

    private interface DisplayNameQuery {
        String[] COLUMNS = new String[] {
            RawContacts._ID,
            RawContactsColumns.DISPLAY_NAME,
            RawContactsColumns.DISPLAY_NAME_SOURCE,
            RawContacts.NAME_VERIFIED,
            RawContacts.SOURCE_ID,
            RawContacts.ACCOUNT_TYPE,
        };

        int _ID = 0;
        int DISPLAY_NAME = 1;
        int DISPLAY_NAME_SOURCE = 2;
        int NAME_VERIFIED = 3;
        int SOURCE_ID = 4;
        int ACCOUNT_TYPE = 5;
    }

    public void updateDisplayNameForRawContact(SQLiteDatabase db, long rawContactId) {
        long contactId = mDbHelper.getContactId(rawContactId);
        if (contactId == 0) {
            return;
        }

        updateDisplayNameForContact(db, contactId);
    }

    public void updateDisplayNameForContact(SQLiteDatabase db, long contactId) {
        boolean lookupKeyUpdateNeeded = false;

        mDisplayNameCandidate.clear();

        mSelectionArgs1[0] = String.valueOf(contactId);
        final Cursor c = db.query(Tables.RAW_CONTACTS, DisplayNameQuery.COLUMNS,
                RawContacts.CONTACT_ID + "=?", mSelectionArgs1, null, null, null);
        try {
            while (c.moveToNext()) {
                long rawContactId = c.getLong(DisplayNameQuery._ID);
                String displayName = c.getString(DisplayNameQuery.DISPLAY_NAME);
                int displayNameSource = c.getInt(DisplayNameQuery.DISPLAY_NAME_SOURCE);
                int nameVerified = c.getInt(DisplayNameQuery.NAME_VERIFIED);
                String accountType = c.getString(DisplayNameQuery.ACCOUNT_TYPE);

                processDisplayNameCanditate(rawContactId, displayName, displayNameSource,
                        mContactsProvider.isWritableAccount(accountType), nameVerified != 0);

                // If the raw contact has no source id, the lookup key is based on the display
                // name, so the lookup key needs to be updated.
                lookupKeyUpdateNeeded |= c.isNull(DisplayNameQuery.SOURCE_ID);
            }
        } finally {
            c.close();
        }

        if (mDisplayNameCandidate.rawContactId != -1) {
            mDisplayNameUpdate.bindLong(1, mDisplayNameCandidate.rawContactId);
            mDisplayNameUpdate.bindLong(2, contactId);
            mDisplayNameUpdate.execute();
        }

        if (lookupKeyUpdateNeeded) {
            updateLookupKeyForContact(db, contactId);
        }
    }

    /**
     * Updates the {@link Contacts#HAS_PHONE_NUMBER} flag for the aggregate contact containing the
     * specified raw contact.
     */
    public void updateHasPhoneNumber(SQLiteDatabase db, long rawContactId) {

        long contactId = mDbHelper.getContactId(rawContactId);
        if (contactId == 0) {
            return;
        }

        mHasPhoneNumberUpdate.bindLong(1, mDbHelper.getMimeTypeId(Phone.CONTENT_ITEM_TYPE));
        mHasPhoneNumberUpdate.bindLong(2, contactId);
        mHasPhoneNumberUpdate.bindLong(3, contactId);
        mHasPhoneNumberUpdate.execute();
    }

    private interface LookupKeyQuery {
        String[] COLUMNS = new String[] {
            RawContacts._ID,
            RawContactsColumns.DISPLAY_NAME,
            RawContacts.ACCOUNT_TYPE,
            RawContacts.ACCOUNT_NAME,
            RawContacts.SOURCE_ID,
        };

        int ID = 0;
        int DISPLAY_NAME = 1;
        int ACCOUNT_TYPE = 2;
        int ACCOUNT_NAME = 3;
        int SOURCE_ID = 4;
    }

    public void updateLookupKeyForRawContact(SQLiteDatabase db, long rawContactId) {
        long contactId = mDbHelper.getContactId(rawContactId);
        if (contactId == 0) {
            return;
        }

        updateLookupKeyForContact(db, contactId);
    }

    public void updateLookupKeyForContact(SQLiteDatabase db, long contactId) {
        mSb.setLength(0);
        mSelectionArgs1[0] = String.valueOf(contactId);
        final Cursor c = db.query(Tables.RAW_CONTACTS, LookupKeyQuery.COLUMNS,
                RawContacts.CONTACT_ID + "=?", mSelectionArgs1, null, null, RawContacts._ID);
        try {
            while (c.moveToNext()) {
                ContactLookupKey.appendToLookupKey(mSb,
                        c.getString(LookupKeyQuery.ACCOUNT_TYPE),
                        c.getString(LookupKeyQuery.ACCOUNT_NAME),
                        c.getLong(LookupKeyQuery.ID),
                        c.getString(LookupKeyQuery.SOURCE_ID),
                        c.getString(LookupKeyQuery.DISPLAY_NAME));
            }
        } finally {
            c.close();
        }

        if (mSb.length() == 0) {
            mLookupKeyUpdate.bindNull(1);
        } else {
            mLookupKeyUpdate.bindString(1, Uri.encode(mSb.toString()));
        }
        mLookupKeyUpdate.bindLong(2, contactId);

        mLookupKeyUpdate.execute();
    }

    /**
     * Execute {@link SQLiteStatement} that will update the
     * {@link Contacts#STARRED} flag for the given {@link RawContacts#_ID}.
     */
    protected void updateStarred(long rawContactId) {
        long contactId = mDbHelper.getContactId(rawContactId);
        if (contactId == 0) {
            return;
        }

        mStarredUpdate.bindLong(1, contactId);
        mStarredUpdate.execute();
    }

    /**
     * Finds matching contacts and returns a cursor on those.
     */
    public Cursor queryAggregationSuggestions(SQLiteQueryBuilder qb, String[] projection,
            long contactId, int maxSuggestions, String filter) {
        final SQLiteDatabase db = mDbHelper.getReadableDatabase();

        List<MatchScore> bestMatches = findMatchingContacts(db, contactId);
        return queryMatchingContacts(qb, db, contactId, projection, bestMatches, maxSuggestions,
                filter);
    }

    private interface ContactIdQuery {
        String[] COLUMNS = new String[] {
            Contacts._ID
        };

        int _ID = 0;
    }

    /**
     * Loads contacts with specified IDs and returns them in the order of IDs in the
     * supplied list.
     */
    private Cursor queryMatchingContacts(SQLiteQueryBuilder qb, SQLiteDatabase db, long contactId,
            String[] projection, List<MatchScore> bestMatches, int maxSuggestions, String filter) {

        StringBuilder sb = new StringBuilder();
        sb.append(Contacts._ID);
        sb.append(" IN (");
        for (int i = 0; i < bestMatches.size(); i++) {
            MatchScore matchScore = bestMatches.get(i);
            if (i != 0) {
                sb.append(",");
            }
            sb.append(matchScore.getContactId());
        }
        sb.append(")");

        if (!TextUtils.isEmpty(filter)) {
            sb.append(" AND " + Contacts._ID + " IN ");
            mContactsProvider.appendContactFilterAsNestedQuery(sb, filter);
        }

        // Run a query and find ids of best matching contacts satisfying the filter (if any)
        HashSet<Long> foundIds = new HashSet<Long>();
        Cursor cursor = db.query(qb.getTables(), ContactIdQuery.COLUMNS, sb.toString(),
                null, null, null, null);
        try {
            while(cursor.moveToNext()) {
                foundIds.add(cursor.getLong(ContactIdQuery._ID));
            }
        } finally {
            cursor.close();
        }

        // Exclude all contacts that did not match the filter
        Iterator<MatchScore> iter = bestMatches.iterator();
        while (iter.hasNext()) {
            long id = iter.next().getContactId();
            if (!foundIds.contains(id)) {
                iter.remove();
            }
        }

        // Limit the number of returned suggestions
        if (bestMatches.size() > maxSuggestions) {
            bestMatches = bestMatches.subList(0, maxSuggestions);
        }

        // Build an in-clause with the remaining contact IDs
        sb.setLength(0);
        sb.append(Contacts._ID);
        sb.append(" IN (");
        for (int i = 0; i < bestMatches.size(); i++) {
            MatchScore matchScore = bestMatches.get(i);
            if (i != 0) {
                sb.append(",");
            }
            sb.append(matchScore.getContactId());
        }
        sb.append(")");

        // Run the final query with the required projection and contact IDs found by the first query
        cursor = qb.query(db, projection, sb.toString(), null, null, null, Contacts._ID);

        // Build a sorted list of discovered IDs
        ArrayList<Long> sortedContactIds = new ArrayList<Long>(bestMatches.size());
        for (MatchScore matchScore : bestMatches) {
            sortedContactIds.add(matchScore.getContactId());
        }

        Collections.sort(sortedContactIds);

        // Map cursor indexes according to the descending order of match scores
        int[] positionMap = new int[bestMatches.size()];
        for (int i = 0; i < positionMap.length; i++) {
            long id = bestMatches.get(i).getContactId();
            positionMap[i] = sortedContactIds.indexOf(id);
        }

        return new ReorderingCursorWrapper(cursor, positionMap);
    }

    private interface RawContactIdQuery {
        String TABLE = Tables.RAW_CONTACTS;

        String[] COLUMNS = new String[] {
            RawContacts._ID
        };

        int _ID = 0;
    }

    /**
     * Finds contacts with data matches and returns a list of {@link MatchScore}'s in the
     * descending order of match score.
     */
    private List<MatchScore> findMatchingContacts(final SQLiteDatabase db, long contactId) {

        MatchCandidateList candidates = new MatchCandidateList();
        ContactMatcher matcher = new ContactMatcher();

        // Don't aggregate a contact with itself
        matcher.keepOut(contactId);

        final Cursor c = db.query(RawContactIdQuery.TABLE, RawContactIdQuery.COLUMNS,
                RawContacts.CONTACT_ID + "=" + contactId, null, null, null, null);
        try {
            while (c.moveToNext()) {
                long rawContactId = c.getLong(RawContactIdQuery._ID);
                updateMatchScoresForSuggestionsBasedOnDataMatches(db, rawContactId, candidates,
                        matcher);
            }
        } finally {
            c.close();
        }

        return matcher.pickBestMatches(ContactMatcher.SCORE_THRESHOLD_SUGGEST);
    }

    /**
     * Computes scores for contacts that have matching data rows.
     */
    private void updateMatchScoresForSuggestionsBasedOnDataMatches(SQLiteDatabase db,
            long rawContactId, MatchCandidateList candidates, ContactMatcher matcher) {

        updateMatchScoresBasedOnNameMatches(db, rawContactId, matcher);
        updateMatchScoresBasedOnEmailMatches(db, rawContactId, matcher);
        updateMatchScoresBasedOnPhoneMatches(db, rawContactId, matcher);
        loadNameMatchCandidates(db, rawContactId, candidates, false);
        lookupApproximateNameMatches(db, candidates, matcher);
    }
}