package org.thoughtcrime.securesms.database.helpers;


import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.os.SystemClock;
import android.support.annotation.NonNull;
import android.text.TextUtils;
import android.util.Log;

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

import org.thoughtcrime.securesms.crypto.DatabaseSecret;

import java.io.File;

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 MIGRATE_SESSIONS_VERSION         = 4;
  private static final int NO_MORE_IMAGE_THUMBNAILS_VERSION = 5;
  private static final int ATTACHMENT_DIMENSIONS            = 6;
  private static final int QUOTED_REPLIES                   = 7;
  private static final int SHARED_CONTACTS                  = 8;
  private static final int FULL_TEXT_SEARCH                 = 9;
  private static final int BAD_IMPORT_CLEANUP               = 10;

  private static final int    DATABASE_VERSION = 10;
  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) {
  }

  @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 0");
      }

      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 (oldVersion < MIGRATE_SESSIONS_VERSION) {
        db.execSQL("CREATE TABLE sessions (_id INTEGER PRIMARY KEY, address TEXT NOT NULL, device INTEGER NOT NULL, record BLOB NOT NULL, UNIQUE(address, device) ON CONFLICT REPLACE)");
//        SessionStoreMigrationHelper.migrateSessions(context, db);
      }

      if (oldVersion < NO_MORE_IMAGE_THUMBNAILS_VERSION) {
        ContentValues update = new ContentValues();
        update.put("thumbnail", (String)null);
        update.put("aspect_ratio", (String)null);
        update.put("thumbnail_random", (String)null);

        try (Cursor cursor = db.query("part", new String[] {"_id", "ct", "thumbnail"}, "thumbnail IS NOT NULL", null, null, null, null)) {
          while (cursor != null && cursor.moveToNext()) {
            long   id          = cursor.getLong(cursor.getColumnIndexOrThrow("_id"));
            String contentType = cursor.getString(cursor.getColumnIndexOrThrow("ct"));

            if (contentType != null && !contentType.startsWith("video")) {
              String thumbnailPath = cursor.getString(cursor.getColumnIndexOrThrow("thumbnail"));
              File   thumbnailFile = new File(thumbnailPath);
              thumbnailFile.delete();

              db.update("part", update, "_id = ?", new String[] {String.valueOf(id)});
            }
          }
        }
      }

      if (oldVersion < ATTACHMENT_DIMENSIONS) {
        db.execSQL("ALTER TABLE part ADD COLUMN width INTEGER DEFAULT 0");
        db.execSQL("ALTER TABLE part ADD COLUMN height INTEGER DEFAULT 0");
      }

      if (oldVersion < QUOTED_REPLIES) {
        db.execSQL("ALTER TABLE mms ADD COLUMN quote_id INTEGER DEFAULT 0");
        db.execSQL("ALTER TABLE mms ADD COLUMN quote_author TEXT");
        db.execSQL("ALTER TABLE mms ADD COLUMN quote_body TEXT");
        db.execSQL("ALTER TABLE mms ADD COLUMN quote_attachment INTEGER DEFAULT -1");

        db.execSQL("ALTER TABLE part ADD COLUMN quote INTEGER DEFAULT 0");
      }

      if (oldVersion < SHARED_CONTACTS) {
        db.execSQL("ALTER TABLE mms ADD COLUMN shared_contacts TEXT");
      }

      if (oldVersion < FULL_TEXT_SEARCH) {

        Log.i(TAG, "Beginning to build search index.");
        long start = SystemClock.elapsedRealtime();

        db.execSQL("INSERT INTO sms_fts (rowid, body) SELECT _id, body FROM sms");

        long smsFinished = SystemClock.elapsedRealtime();
        Log.i(TAG, "Indexing SMS completed in " + (smsFinished - start) + " ms");

        db.execSQL("INSERT INTO mms_fts (rowid, body) SELECT _id, body FROM mms");

        long mmsFinished = SystemClock.elapsedRealtime();
        Log.i(TAG, "Indexing MMS completed in " + (mmsFinished - smsFinished) + " ms");
        Log.i(TAG, "Indexing finished. Total time: " + (mmsFinished - start) + " ms");
      }

      if (oldVersion < BAD_IMPORT_CLEANUP) {
        String trimmedCondition = " NOT IN (SELECT _id FROM mms)";

        db.delete("group_receipts", "mms_id" + trimmedCondition, null);

        String[] columns = new String[] { "_id", "unique_id", "_data", "thumbnail"};

        try (Cursor cursor = db.query("part", columns, "mid" + trimmedCondition, null, null, null, null)) {
          while (cursor != null && cursor.moveToNext()) {
            db.delete("part", "_id = ? AND unique_id = ?", new String[] { String.valueOf(cursor.getLong(0)), String.valueOf(cursor.getLong(1)) });

            String data      = cursor.getString(2);
            String thumbnail = cursor.getString(3);

            if (!TextUtils.isEmpty(data)) {
              new File(data).delete();
            }

            if (!TextUtils.isEmpty(thumbnail)) {
              new File(thumbnail).delete();
            }
          }
        }
      }

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

  }

  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);
  }


}