/**
 * Copyright (C) 2013 Open Whisper Systems
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
package org.thoughtcrime.securesms.contacts;

import android.accounts.Account;
import android.content.ContentProviderOperation;
import android.content.Context;
import android.content.OperationApplicationException;
import android.database.Cursor;
import android.database.CursorWrapper;
import android.net.Uri;
import android.os.Build;
import android.os.RemoteException;
import android.provider.BaseColumns;
import android.provider.ContactsContract;
import android.provider.ContactsContract.RawContacts;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import android.text.TextUtils;
import android.util.Log;
import android.util.Pair;

import org.thoughtcrime.securesms.R;
import org.whispersystems.libaxolotl.util.guava.Optional;
import org.whispersystems.textsecure.api.push.ContactTokenDetails;
import org.whispersystems.textsecure.api.util.InvalidNumberException;
import org.whispersystems.textsecure.api.util.PhoneNumberFormatter;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;

/**
 * Database to supply all types of contacts that TextSecure needs to know about
 *
 * @author Jake McGinty
 */
public class ContactsDatabase {

  private static final String TAG              = ContactsDatabase.class.getSimpleName();
  private static final String CONTACT_MIMETYPE = "vnd.android.cursor.item/vnd.org.thoughtcrime.securesms.contact";
  private static final String CALL_MIMETYPE    = "vnd.android.cursor.item/vnd.org.thoughtcrime.securesms.call";
  private static final String SYNC             = "__TS";

  public static final String ID_COLUMN           = "_id";
  public static final String NAME_COLUMN         = "name";
  public static final String NUMBER_COLUMN       = "number";
  public static final String NUMBER_TYPE_COLUMN  = "number_type";
  public static final String LABEL_COLUMN        = "label";
  public static final String CONTACT_TYPE_COLUMN = "contact_type";

  public static final int NORMAL_TYPE = 0;
  public static final int PUSH_TYPE   = 1;
  public static final int NEW_TYPE    = 2;

  private final Context context;

  public ContactsDatabase(Context context) {
    this.context  = context;
  }

  public synchronized @NonNull List<String> setRegisteredUsers(@NonNull Account account,
                                                               @NonNull String localNumber,
                                                               @NonNull List<ContactTokenDetails> registeredContacts,
                                                               boolean remove)
      throws RemoteException, OperationApplicationException
  {

    Map<String, ContactTokenDetails>    registeredNumbers = new HashMap<>();
    List<String>                        addedNumbers      = new LinkedList<>();
    ArrayList<ContentProviderOperation> operations        = new ArrayList<>();
    Map<String, SignalContact>          currentContacts   = getSignalRawContacts(account, localNumber);

    for (ContactTokenDetails registeredContact : registeredContacts) {
      String registeredNumber = registeredContact.getNumber();

      registeredNumbers.put(registeredNumber, registeredContact);

      if (!currentContacts.containsKey(registeredNumber)) {
        Optional<SystemContactInfo> systemContactInfo = getSystemContactInfo(registeredNumber, localNumber);

        if (systemContactInfo.isPresent()) {
          Log.w(TAG, "Adding number: " + registeredNumber);
          addedNumbers.add(registeredNumber);
          addTextSecureRawContact(operations, account, systemContactInfo.get().number,
                                  systemContactInfo.get().id, registeredContact.isVoice());
        }
      }
    }

    for (Map.Entry<String, SignalContact> currentContactEntry : currentContacts.entrySet()) {
      ContactTokenDetails tokenDetails = registeredNumbers.get(currentContactEntry.getKey());

      if (tokenDetails == null) {
        if (remove) {
          Log.w(TAG, "Removing number: " + currentContactEntry.getKey());
          removeTextSecureRawContact(operations, account, currentContactEntry.getValue().getId());
        }
      } else if (tokenDetails.isVoice() && !currentContactEntry.getValue().isVoiceSupported()) {
        Log.w(TAG, "Adding voice support: " + currentContactEntry.getKey());
        addContactVoiceSupport(operations, currentContactEntry.getKey(), currentContactEntry.getValue().getId());
      } else if (!tokenDetails.isVoice() && currentContactEntry.getValue().isVoiceSupported()) {
        Log.w(TAG, "Removing voice support: " + currentContactEntry.getKey());
        removeContactVoiceSupport(operations, currentContactEntry.getValue().getId());
      }
    }

    if (!operations.isEmpty()) {
      context.getContentResolver().applyBatch(ContactsContract.AUTHORITY, operations);
    }

    return addedNumbers;
  }

  public @NonNull Cursor querySystemContacts(String filter) {
    Uri uri;

    if (!TextUtils.isEmpty(filter)) {
      uri = Uri.withAppendedPath(ContactsContract.CommonDataKinds.Phone.CONTENT_FILTER_URI, Uri.encode(filter));
    } else {
      uri = ContactsContract.CommonDataKinds.Phone.CONTENT_URI;
    }

    if (android.os.Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
      uri = uri.buildUpon().appendQueryParameter(ContactsContract.REMOVE_DUPLICATE_ENTRIES, "true").build();
    }

    String[] projection = new String[]{ContactsContract.CommonDataKinds.Phone._ID,
                                       ContactsContract.CommonDataKinds.Phone.DISPLAY_NAME,
                                       ContactsContract.CommonDataKinds.Phone.NUMBER,
                                       ContactsContract.CommonDataKinds.Phone.TYPE,
                                       ContactsContract.CommonDataKinds.Phone.LABEL};

    String sort = ContactsContract.CommonDataKinds.Phone.DISPLAY_NAME + " COLLATE NOCASE ASC";

    Map<String, String> projectionMap = new HashMap<String, String>() {{
      put(ID_COLUMN, ContactsContract.CommonDataKinds.Phone._ID);
      put(NAME_COLUMN, ContactsContract.CommonDataKinds.Phone.DISPLAY_NAME);
      put(NUMBER_COLUMN, ContactsContract.CommonDataKinds.Phone.NUMBER);
      put(NUMBER_TYPE_COLUMN, ContactsContract.CommonDataKinds.Phone.TYPE);
      put(LABEL_COLUMN, ContactsContract.CommonDataKinds.Phone.LABEL);
    }};

    Cursor cursor = context.getContentResolver().query(uri, projection,
                                                       ContactsContract.Data.SYNC2 + " IS NULL OR " +
                                                       ContactsContract.Data.SYNC2 + " != ?",
                                                       new String[] {SYNC},
                                                       sort);

    return new ProjectionMappingCursor(cursor, projectionMap,
                                       new Pair<String, Object>(CONTACT_TYPE_COLUMN, NORMAL_TYPE));
  }

  public @NonNull Cursor queryTextSecureContacts(String filter) {
    String[] projection = new String[] {ContactsContract.Data._ID,
                                        ContactsContract.Contacts.DISPLAY_NAME,
                                        ContactsContract.Data.DATA1};

    String  sort = ContactsContract.Contacts.DISPLAY_NAME + " COLLATE NOCASE ASC";

    Map<String, String> projectionMap = new HashMap<String, String>(){{
      put(ID_COLUMN, ContactsContract.Data._ID);
      put(NAME_COLUMN, ContactsContract.Contacts.DISPLAY_NAME);
      put(NUMBER_COLUMN, ContactsContract.Data.DATA1);
    }};

    Cursor cursor;

    if (TextUtils.isEmpty(filter)) {
      cursor = context.getContentResolver().query(ContactsContract.Data.CONTENT_URI,
                                                  projection,
                                                  ContactsContract.Data.MIMETYPE + " = ?",
                                                  new String[] {CONTACT_MIMETYPE},
                                                  sort);
    } else {
      cursor = context.getContentResolver().query(ContactsContract.Data.CONTENT_URI,
                                                  projection,
                                                  ContactsContract.Data.MIMETYPE + " = ? AND (" + ContactsContract.Contacts.DISPLAY_NAME + " LIKE ? OR " + ContactsContract.Data.DATA1 + " LIKE ?)",
                                                  new String[] {CONTACT_MIMETYPE,
                                                                "%" + filter + "%", "%" + filter + "%"},
                                                  sort);
    }

    return new ProjectionMappingCursor(cursor, projectionMap,
                                       new Pair<String, Object>(LABEL_COLUMN, "TextSecure"),
                                       new Pair<String, Object>(NUMBER_TYPE_COLUMN, 0),
                                       new Pair<String, Object>(CONTACT_TYPE_COLUMN, PUSH_TYPE));

  }

  private void addContactVoiceSupport(List<ContentProviderOperation> operations,
                                      @NonNull String e164number, long rawContactId)
  {
    operations.add(ContentProviderOperation.newUpdate(RawContacts.CONTENT_URI)
                                           .withSelection(RawContacts._ID + " = ?", new String[] {String.valueOf(rawContactId)})
                                           .withValue(RawContacts.SYNC4, "true")
                                           .build());

    operations.add(ContentProviderOperation.newInsert(ContactsContract.Data.CONTENT_URI.buildUpon().appendQueryParameter(ContactsContract.CALLER_IS_SYNCADAPTER, "true").build())
                                           .withValue(ContactsContract.Data.RAW_CONTACT_ID, rawContactId)
                                           .withValue(ContactsContract.Data.MIMETYPE, CALL_MIMETYPE)
                                           .withValue(ContactsContract.Data.DATA1, e164number)
                                           .withValue(ContactsContract.Data.DATA2, context.getString(R.string.app_name))
                                           .withValue(ContactsContract.Data.DATA3, context.getString(R.string.ContactsDatabase_signal_call_s, e164number))
                                           .withYieldAllowed(true)
                                           .build());
  }

  private void removeContactVoiceSupport(List<ContentProviderOperation> operations, long rawContactId) {
    operations.add(ContentProviderOperation.newUpdate(RawContacts.CONTENT_URI)
                                           .withSelection(RawContacts._ID + " = ?", new String[] {String.valueOf(rawContactId)})
                                           .withValue(RawContacts.SYNC4, "false")
                                           .build());

    operations.add(ContentProviderOperation.newDelete(ContactsContract.Data.CONTENT_URI.buildUpon().appendQueryParameter(ContactsContract.CALLER_IS_SYNCADAPTER, "true").build())
                                           .withSelection(ContactsContract.Data.RAW_CONTACT_ID + " = ? AND " + ContactsContract.Data.MIMETYPE + " = ?",
                                                          new String[] {String.valueOf(rawContactId), CALL_MIMETYPE})
                                           .withYieldAllowed(true)
                                           .build());
  }

  private void addTextSecureRawContact(List<ContentProviderOperation> operations,
                                       Account account, String e164number,
                                       long aggregateId, boolean supportsVoice)
  {
    int index   = operations.size();
    Uri dataUri = ContactsContract.Data.CONTENT_URI.buildUpon()
                                                   .appendQueryParameter(ContactsContract.CALLER_IS_SYNCADAPTER, "true")
                                                   .build();

    operations.add(ContentProviderOperation.newInsert(RawContacts.CONTENT_URI)
                                           .withValue(RawContacts.ACCOUNT_NAME, account.name)
                                           .withValue(RawContacts.ACCOUNT_TYPE, account.type)
                                           .withValue(RawContacts.SYNC1, e164number)
                                           .withValue(RawContacts.SYNC4, String.valueOf(supportsVoice))
                                           .build());

    operations.add(ContentProviderOperation.newInsert(dataUri)
                                           .withValueBackReference(ContactsContract.CommonDataKinds.Phone.RAW_CONTACT_ID, index)
                                           .withValue(ContactsContract.Data.MIMETYPE, ContactsContract.CommonDataKinds.Phone.CONTENT_ITEM_TYPE)
                                           .withValue(ContactsContract.CommonDataKinds.Phone.NUMBER, e164number)
                                           .withValue(ContactsContract.CommonDataKinds.Phone.TYPE, ContactsContract.CommonDataKinds.Phone.TYPE_OTHER)
                                           .withValue(ContactsContract.Data.SYNC2, SYNC)
                                           .build());

    operations.add(ContentProviderOperation.newInsert(dataUri)
                                           .withValueBackReference(ContactsContract.Data.RAW_CONTACT_ID, index)
                                           .withValue(ContactsContract.Data.MIMETYPE, CONTACT_MIMETYPE)
                                           .withValue(ContactsContract.Data.DATA1, e164number)
                                           .withValue(ContactsContract.Data.DATA2, context.getString(R.string.app_name))
                                           .withValue(ContactsContract.Data.DATA3, context.getString(R.string.ContactsDatabase_message_s, e164number))
                                           .withYieldAllowed(true)
                                           .build());

    if (supportsVoice) {
      operations.add(ContentProviderOperation.newInsert(dataUri)
                                             .withValueBackReference(ContactsContract.Data.RAW_CONTACT_ID, index)
                                             .withValue(ContactsContract.Data.MIMETYPE, CALL_MIMETYPE)
                                             .withValue(ContactsContract.Data.DATA1, e164number)
                                             .withValue(ContactsContract.Data.DATA2, context.getString(R.string.app_name))
                                             .withValue(ContactsContract.Data.DATA3, context.getString(R.string.ContactsDatabase_signal_call_s, e164number))
                                             .withYieldAllowed(true)
                                             .build());
    }


    if (Build.VERSION.SDK_INT >= 11) {
      operations.add(ContentProviderOperation.newUpdate(ContactsContract.AggregationExceptions.CONTENT_URI)
                                             .withValue(ContactsContract.AggregationExceptions.RAW_CONTACT_ID1, aggregateId)
                                             .withValueBackReference(ContactsContract.AggregationExceptions.RAW_CONTACT_ID2, index)
                                             .withValue(ContactsContract.AggregationExceptions.TYPE, ContactsContract.AggregationExceptions.TYPE_KEEP_TOGETHER)
                                             .build());
    }
  }

  private void removeTextSecureRawContact(List<ContentProviderOperation> operations,
                                          Account account, long rowId)
  {
    operations.add(ContentProviderOperation.newDelete(RawContacts.CONTENT_URI.buildUpon()
                                                                             .appendQueryParameter(RawContacts.ACCOUNT_NAME, account.name)
                                                                             .appendQueryParameter(RawContacts.ACCOUNT_TYPE, account.type)
                                                                             .appendQueryParameter(ContactsContract.CALLER_IS_SYNCADAPTER, "true").build())
                                           .withYieldAllowed(true)
                                           .withSelection(BaseColumns._ID + " = ?", new String[] {String.valueOf(rowId)})
                                           .build());
  }

  private @NonNull Map<String, SignalContact> getSignalRawContacts(@NonNull Account account,
                                                                   @NonNull String localNumber)
  {
    Uri currentContactsUri = RawContacts.CONTENT_URI.buildUpon()
                                                    .appendQueryParameter(RawContacts.ACCOUNT_NAME, account.name)
                                                    .appendQueryParameter(RawContacts.ACCOUNT_TYPE, account.type).build();

    Map<String, SignalContact> signalContacts = new HashMap<>();
    Cursor                     cursor         = null;

    try {
      cursor = context.getContentResolver().query(currentContactsUri, new String[] {BaseColumns._ID, RawContacts.SYNC1, RawContacts.SYNC4}, null, null, null);

      while (cursor != null && cursor.moveToNext()) {
        String currentNumber;

        try {
          currentNumber = PhoneNumberFormatter.formatNumber(cursor.getString(1), localNumber);
        } catch (InvalidNumberException e) {
          Log.w(TAG, e);
          currentNumber = cursor.getString(1);
        }

        signalContacts.put(currentNumber, new SignalContact(cursor.getLong(0), cursor.getString(2)));
      }
    } finally {
      if (cursor != null)
        cursor.close();
    }

    return signalContacts;
  }

  private Optional<SystemContactInfo> getSystemContactInfo(@NonNull String e164number,
                                                           @NonNull String localNumber)
  {
    Uri      uri          = Uri.withAppendedPath(ContactsContract.PhoneLookup.CONTENT_FILTER_URI, Uri.encode(e164number));
    String[] projection   = {ContactsContract.PhoneLookup.NUMBER,
                             ContactsContract.PhoneLookup._ID,
                             ContactsContract.PhoneLookup.DISPLAY_NAME};
    Cursor   numberCursor = null;
    Cursor   idCursor     = null;

    try {
      numberCursor = context.getContentResolver().query(uri, projection, null, null, null);

      while (numberCursor != null && numberCursor.moveToNext()) {
        try {
          String systemNumber              = numberCursor.getString(0);
          String canonicalizedSystemNumber = PhoneNumberFormatter.formatNumber(systemNumber, localNumber);

          if (canonicalizedSystemNumber.equals(e164number)) {
            idCursor = context.getContentResolver().query(RawContacts.CONTENT_URI,
                                                          new String[] {RawContacts._ID},
                                                          RawContacts.CONTACT_ID + " = ? ",
                                                          new String[] {String.valueOf(numberCursor.getLong(1))},
                                                          null);

            if (idCursor != null && idCursor.moveToNext()) {
              return Optional.of(new SystemContactInfo(numberCursor.getString(2),
                                                       numberCursor.getString(0),
                                                       idCursor.getLong(0)));
            }
          }
        } catch (InvalidNumberException e) {
          Log.w(TAG, e);
        }
      }
    } finally {
      if (numberCursor != null) numberCursor.close();
      if (idCursor     != null) idCursor.close();
    }

    return Optional.absent();
  }

  private static class ProjectionMappingCursor extends CursorWrapper {

    private final Map<String, String>    projectionMap;
    private final Pair<String, Object>[] extras;

    @SafeVarargs
    public ProjectionMappingCursor(Cursor cursor,
                                   Map<String, String> projectionMap,
                                   Pair<String, Object>... extras)
    {
      super(cursor);
      this.projectionMap = projectionMap;
      this.extras        = extras;
    }

    @Override
    public int getColumnCount() {
      return super.getColumnCount() + extras.length;
    }

    @Override
    public int getColumnIndex(String columnName) {
      for (int i=0;i<extras.length;i++) {
        if (extras[i].first.equals(columnName)) {
          return super.getColumnCount() + i;
        }
      }

      return super.getColumnIndex(projectionMap.get(columnName));
    }

    @Override
    public int getColumnIndexOrThrow(String columnName) throws IllegalArgumentException {
      int index = getColumnIndex(columnName);

      if (index == -1) throw new IllegalArgumentException("Bad column name!");
      else             return index;
    }

    @Override
    public String getColumnName(int columnIndex) {
      int baseColumnCount = super.getColumnCount();

      if (columnIndex >= baseColumnCount) {
        int offset = columnIndex - baseColumnCount;
        return extras[offset].first;
      }

      return getReverseProjection(super.getColumnName(columnIndex));
    }

    @Override
    public String[] getColumnNames() {
      String[] names    = super.getColumnNames();
      String[] allNames = new String[names.length + extras.length];

      for (int i=0;i<names.length;i++) {
        allNames[i] = getReverseProjection(names[i]);
      }

      for (int i=0;i<extras.length;i++) {
        allNames[names.length + i] = extras[i].first;
      }

      return allNames;
    }

    @Override
    public int getInt(int columnIndex) {
      if (columnIndex >= super.getColumnCount()) {
        int offset = columnIndex - super.getColumnCount();
        return (Integer)extras[offset].second;
      }

      return super.getInt(columnIndex);
    }

    @Override
    public String getString(int columnIndex) {
      if (columnIndex >= super.getColumnCount()) {
        int offset = columnIndex - super.getColumnCount();
        return (String)extras[offset].second;
      }

      return super.getString(columnIndex);
    }


    private @Nullable String getReverseProjection(String columnName) {
      for (Map.Entry<String, String> entry : projectionMap.entrySet()) {
        if (entry.getValue().equals(columnName)) {
          return entry.getKey();
        }
      }

      return null;
    }
  }

  private static class SystemContactInfo {
    private final String name;
    private final String number;
    private final long   id;

    private SystemContactInfo(String name, String number, long id) {
      this.name   = name;
      this.number = number;
      this.id     = id;
    }
  }

  private static class SignalContact {
              private final long   id;
    @Nullable private final String supportsVoice;

    public SignalContact(long id, @Nullable String supportsVoice) {
      this.id            = id;
      this.supportsVoice = supportsVoice;
    }

    public long getId() {
      return id;
    }

    public boolean isVoiceSupported() {
      return "true".equals(supportsVoice);
    }
  }
}