package org.thoughtcrime.securesms.database.helpers;


import android.content.Context;
import android.support.annotation.NonNull;
import android.util.Log;

import net.sqlcipher.database.SQLiteDatabase;
import net.sqlcipher.database.SQLiteDatabaseHook;
import net.sqlcipher.database.SQLiteOpenHelper;

import org.thoughtcrime.securesms.ApplicationContext;
import org.thoughtcrime.securesms.crypto.DatabaseSecret;
import org.thoughtcrime.securesms.crypto.MasterSecret;
import org.thoughtcrime.securesms.database.AttachmentDatabase;
import org.thoughtcrime.securesms.database.DraftDatabase;
import org.thoughtcrime.securesms.database.GroupDatabase;
import org.thoughtcrime.securesms.database.GroupReceiptDatabase;
import org.thoughtcrime.securesms.database.IdentityDatabase;
import org.thoughtcrime.securesms.database.MmsDatabase;
import org.thoughtcrime.securesms.database.OneTimePreKeyDatabase;
import org.thoughtcrime.securesms.database.PushDatabase;
import org.thoughtcrime.securesms.database.RecipientDatabase;
import org.thoughtcrime.securesms.database.SignedPreKeyDatabase;
import org.thoughtcrime.securesms.database.SmsDatabase;
import org.thoughtcrime.securesms.database.ThreadDatabase;
import org.thoughtcrime.securesms.jobs.RefreshPreKeysJob;
import org.thoughtcrime.securesms.service.KeyCachingService;
import org.thoughtcrime.securesms.util.TextSecurePreferences;

public class SQLCipherOpenHelper extends SQLiteOpenHelper {

  @SuppressWarnings("unused")
  private static final String TAG = SQLCipherOpenHelper.class.getSimpleName();

  private static final int RECIPIENT_CALL_RINGTONE_VERSION = 2;
  private static final int MIGRATE_PREKEYS_VERSION         = 3;

  private static final int    DATABASE_VERSION = 3;
  private static final String DATABASE_NAME    = "signal.db";

  private final Context        context;
  private final DatabaseSecret databaseSecret;

  public SQLCipherOpenHelper(@NonNull Context context, @NonNull DatabaseSecret databaseSecret) {
    super(context, DATABASE_NAME, null, DATABASE_VERSION, new SQLiteDatabaseHook() {
      @Override
      public void preKey(SQLiteDatabase db) {
        db.rawExecSQL("PRAGMA cipher_default_kdf_iter = 1;");
        db.rawExecSQL("PRAGMA cipher_default_page_size = 4096;");
      }

      @Override
      public void postKey(SQLiteDatabase db) {
        db.rawExecSQL("PRAGMA kdf_iter = '1';");
        db.rawExecSQL("PRAGMA cipher_page_size = 4096;");
      }
    });

    this.context        = context.getApplicationContext();
    this.databaseSecret = databaseSecret;
  }

  @Override
  public void onCreate(SQLiteDatabase db) {
    db.execSQL(SmsDatabase.CREATE_TABLE);
    db.execSQL(MmsDatabase.CREATE_TABLE);
    db.execSQL(AttachmentDatabase.CREATE_TABLE);
    db.execSQL(ThreadDatabase.CREATE_TABLE);
    db.execSQL(IdentityDatabase.CREATE_TABLE);
    db.execSQL(DraftDatabase.CREATE_TABLE);
    db.execSQL(PushDatabase.CREATE_TABLE);
    db.execSQL(GroupDatabase.CREATE_TABLE);
    db.execSQL(RecipientDatabase.CREATE_TABLE);
    db.execSQL(GroupReceiptDatabase.CREATE_TABLE);
    db.execSQL(OneTimePreKeyDatabase.CREATE_TABLE);
    db.execSQL(SignedPreKeyDatabase.CREATE_TABLE);

    executeStatements(db, SmsDatabase.CREATE_INDEXS);
    executeStatements(db, MmsDatabase.CREATE_INDEXS);
    executeStatements(db, AttachmentDatabase.CREATE_INDEXS);
    executeStatements(db, ThreadDatabase.CREATE_INDEXS);
    executeStatements(db, DraftDatabase.CREATE_INDEXS);
    executeStatements(db, GroupDatabase.CREATE_INDEXS);
    executeStatements(db, GroupReceiptDatabase.CREATE_INDEXES);

    if (context.getDatabasePath(ClassicOpenHelper.NAME).exists()) {
      ClassicOpenHelper                      legacyHelper = new ClassicOpenHelper(context);
      android.database.sqlite.SQLiteDatabase legacyDb     = legacyHelper.getWritableDatabase();

      SQLCipherMigrationHelper.migratePlaintext(context, legacyDb, db);

      MasterSecret masterSecret = KeyCachingService.getMasterSecret(context);

      if (masterSecret != null) SQLCipherMigrationHelper.migrateCiphertext(context, masterSecret, legacyDb, db, null);
      else                      TextSecurePreferences.setNeedsSqlCipherMigration(context, true);

      if (!PreKeyMigrationHelper.migratePreKeys(context, db)) {
        ApplicationContext.getInstance(context).getJobManager().add(new RefreshPreKeysJob(context));
      }

      PreKeyMigrationHelper.cleanUpPreKeys(context);
    }
  }

  @Override
  public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
    Log.w(TAG, "Upgrading database: " + oldVersion + ", " + newVersion);

    db.beginTransaction();

    try {

      if (oldVersion < RECIPIENT_CALL_RINGTONE_VERSION) {
        db.execSQL("ALTER TABLE recipient_preferences ADD COLUMN call_ringtone TEXT DEFAULT NULL");
        db.execSQL("ALTER TABLE recipient_preferences ADD COLUMN call_vibrate INTEGER DEFAULT " + RecipientDatabase.VibrateState.DEFAULT.getId());
      }

      if (oldVersion < MIGRATE_PREKEYS_VERSION) {
        db.execSQL("CREATE TABLE signed_prekeys (_id INTEGER PRIMARY KEY, key_id INTEGER UNIQUE, public_key TEXT NOT NULL, private_key TEXT NOT NULL, signature TEXT NOT NULL, timestamp INTEGER DEFAULT 0)");
        db.execSQL("CREATE TABLE one_time_prekeys (_id INTEGER PRIMARY KEY, key_id INTEGER UNIQUE, public_key TEXT NOT NULL, private_key TEXT NOT NULL)");

        if (!PreKeyMigrationHelper.migratePreKeys(context, db)) {
          ApplicationContext.getInstance(context).getJobManager().add(new RefreshPreKeysJob(context));
        }

        PreKeyMigrationHelper.cleanUpPreKeys(context);
      }

      db.setTransactionSuccessful();
    } finally {
      db.endTransaction();
    }

    if (oldVersion < MIGRATE_PREKEYS_VERSION) {
      PreKeyMigrationHelper.cleanUpPreKeys(context);
    }
  }

  public SQLiteDatabase getReadableDatabase() {
    return getReadableDatabase(databaseSecret.asString());
  }

  public SQLiteDatabase getWritableDatabase() {
    return getWritableDatabase(databaseSecret.asString());
  }

  private void executeStatements(SQLiteDatabase db, String[] statements) {
    for (String statement : statements)
      db.execSQL(statement);
  }


}