org.cardanofoundation.conversions.converters.TimeConversions Maven / Gradle / Ivy

package org.cardanofoundation.conversions.converters;

import static org.cardanofoundation.conversions.domain.EraType.Byron;
import static org.cardanofoundation.conversions.domain.EraType.Shelley;

import java.time.Duration;
import java.time.LocalDateTime;
import java.time.temporal.ChronoUnit;
import lombok.RequiredArgsConstructor;
import org.cardanofoundation.conversions.GenesisConfig;
import org.cardanofoundation.conversions.domain.EraType;

@RequiredArgsConstructor
public class TimeConversions {

  private final GenesisConfig genesisConfig;

  private final SlotConversions slotsConversions;

  /**
   * Based on UTC time find out what is the epoch number.
   *
   * @param utcTime - UTC time
   * @return epoch number for this time
   */
  public int utcTimeToEpochNo(LocalDateTime utcTime) {
    var lastGenesisSlot = genesisConfig.lastByronSlot();
    var lastByronSlotTime = slotsConversions.slotToTime(lastGenesisSlot);

    if (utcTime.isBefore(lastByronSlotTime)) {
      return utcTimeToEpochNo(Byron, utcTime);
    }

    var lastByronEpoch = genesisConfig.lastByronEpochNo();
    var lastByronTime = slotsConversions.slotToTime(genesisConfig.lastByronSlot());

    var diffDuration = Duration.between(lastByronTime, utcTime);
    var diffDurationSeconds = diffDuration.getSeconds();
    var slotsPerEpoch = genesisConfig.slotsPerEpoch(Shelley);
    var shelleyEraLength = genesisConfig.getShelleySlotLength();
    var shelleyEraLengthSeconds = shelleyEraLength.getSeconds();

    var shelleyEpochs =
        (int) Math.ceil((double) diffDurationSeconds / slotsPerEpoch / shelleyEraLengthSeconds);

    return lastByronEpoch + shelleyEpochs;
  }

  int utcTimeToEpochNo(EraType era, LocalDateTime utcTime) {
    var diffDuration = Duration.between(genesisConfig.getStartTime(), utcTime);
    var diffDurationSeconds = diffDuration.getSeconds();
    var slotsPerEpoch = genesisConfig.slotsPerEpoch(era);
    var byronSlotsLength = genesisConfig.getByronSlotLength();
    var byronSlotsLengthSeconds = byronSlotsLength.getSeconds();

    return (int)
        Math.ceil((double) (diffDurationSeconds / slotsPerEpoch / byronSlotsLengthSeconds));
  }

  /**
   * @param utcTime the time to convert into a slot
   * @return the slot corresponding the time passed as input (this might not coincide with a block)
   */
  public Long toSlot(LocalDateTime utcTime) {

    if (utcTime.isBefore(genesisConfig.getStartTime())) {
      throw new IllegalArgumentException("Required that falls before start of the blockchain");
    } else if (utcTime.isBefore(genesisConfig.getShelleyStartTime())) {
      var secondsSinceByronBegin =
          ChronoUnit.SECONDS.between(genesisConfig.getStartTime(), utcTime);
      return secondsSinceByronBegin / genesisConfig.slotDuration(Byron).getSeconds();
    } else {
      var secondsSinceShelleyBegin =
          ChronoUnit.SECONDS.between(genesisConfig.getShelleyStartTime(), utcTime);
      return genesisConfig.firstShelleySlot()
          + secondsSinceShelleyBegin / genesisConfig.slotDuration(Shelley).getSeconds();
    }
  }
}