import { BlockExtended, PoolTag } from "../mempool.interfaces";
import { DB } from "../database";
import logger from "../logger";

export interface EmptyBlocks {
  emptyBlocks: number,
  poolId: number,
}

class BlocksRepository {
  /**
   * Save indexed block data in the database
   */
  public async $saveBlockInDatabase(
    block: BlockExtended,
    blockHash: string,
    coinbaseHex: string | undefined,
    poolTag: PoolTag
  ) {
    const connection = await DB.pool.getConnection();

    try {
      const query = `INSERT INTO blocks(
        height,  hash,     timestamp,    size,
        weight,  tx_count, coinbase_raw, difficulty,
        pool_id, fees,     fee_span,     median_fee
      ) VALUE (
        ?, ?, FROM_UNIXTIME(?), ?,
        ?, ?, ?, ?,
        ?, ?, ?, ?
      )`;

      const params: any[] = [
        block.height, blockHash, block.timestamp, block.size,
        block.weight, block.tx_count, coinbaseHex ? coinbaseHex : "", block.difficulty,
        poolTag.id, 0, "[]", block.medianFee,
      ];

      await connection.query(query, params);
    } catch (e) {
      console.log(e);
      logger.err('$updateBlocksDatabase() error' + (e instanceof Error ? e.message : e));
    }

    connection.release();
  }

  /**
   * Check if a block has already been indexed in the database. Query the databse directly.
   * This can be cached/optimized if required later on to avoid too many db queries.
   */
  public async $isBlockAlreadyIndexed(blockHeight: number) {
    const connection = await DB.pool.getConnection();
    let exists = false;

    const query = `SELECT height from blocks where blocks.height = ${blockHeight}`;
    const [rows]: any[] = await connection.query(query);
    exists = rows.length === 1;
    connection.release();

    return exists;
  }

  /**
   * Count empty blocks for all pools
   */
  public async $countEmptyBlocks(interval: string = "100 YEAR") : Promise<EmptyBlocks[]> {
    const connection = await DB.pool.getConnection();
    const [rows] = await connection.query(`
      SELECT pool_id as poolId
      FROM blocks
      WHERE timestamp BETWEEN DATE_SUB(NOW(), INTERVAL ${interval}) AND NOW()
      AND tx_count = 1;
    `);
    connection.release();

    return <EmptyBlocks[]>rows;
  }

  /**
   * Get blocks count for a period
   */
   public async $blockCount(interval: string = "100 YEAR") : Promise<number> {
    const connection = await DB.pool.getConnection();
    const [rows] = await connection.query(`
      SELECT count(height) as blockCount
      FROM blocks
      WHERE timestamp BETWEEN DATE_SUB(NOW(), INTERVAL ${interval}) AND NOW();
    `);
    connection.release();

    return <number>rows[0].blockCount;
  }
}

export default new BlocksRepository();