/**
 * Defines the TransactionNumber as a combination of blockNumber and position within the block
 */
export default class TransactionNumber {

  /* We set blockNumber and position to be 32 bits each */
  private static readonly bitWidth = 32;

  /**
   * Constructs the transaction number given the block number and position of the transaction in the block.
   */
  public static construct (blockNumber: number, position: number) {
    const transactionNumber =
      blockNumber * (2 ** this.bitWidth)
      + position;

    return transactionNumber;
  }

  /**
   * Returns the block number component of transactionNumber
   */
  public static getBlockNumber (transactionNumber: number) {
    const blockNumber = Math.floor(transactionNumber / (2 ** this.bitWidth));
    return blockNumber;
  }

  /**
   * Returns the position component of transactionNumber
   */
  public static getPosition (transactionNumber: number) {
    const mask = 2 ** TransactionNumber.bitWidth - 1;
    return (transactionNumber & mask);
  }
}