package jmaa.pbc;

import java.util.List;
import java.util.ArrayList;
import com.partisiablockchain.BlockchainAddress;
import com.partisiablockchain.crypto.BlockchainPublicKey;
import com.partisiablockchain.crypto.KeyPair;

/** Search for PBC vanity addresses.
 *
 * <p>Based on Jesper Balman Gravgaard's original version.
 */
public final class PbcVanityAddressSearcher {

  private static final int NUM_THREADS = 8;
  private static final long MAX_ITERATIONS_PER_THREAD = 100_000_000;
  private static final long INITIAL_PING_INTERVAL = 10_000;

  public static void main(String[] args) throws InterruptedException {
      System.out.println("Args: " + List.of(args));
    searchForPrivateKeyWithVanityAddress(args[0], args[1]);
  }

  /**
   * @param vanityPrefix Desired address prefix
   */
  private static void searchForPrivateKeyWithVanityAddress(String vanityPrefix, String vanitySuffix) throws InterruptedException {
      if (!vanityPrefix.startsWith("00")) {
          throw new IllegalArgumentException("Vanity prefix must start with 00.");
      }

      System.out.println("Searching for private key for address prefix \"%s\" and suffix \"%s\" ".formatted(vanityPrefix, vanitySuffix));

    List<Thread> searchers = new ArrayList<>();
    for(int threadIdx=0;threadIdx<NUM_THREADS ;threadIdx++) {
      final Thread searcher = new Thread(new KeySearcher(threadIdx, vanityPrefix, vanitySuffix));
      searcher.start();
      searchers.add(searcher);
    }

    for (Thread searcher : searchers) {
      searcher.join();
    }
  }

  private record KeySearcher(int threadIdx, String vanityPrefix, String vanitySuffix) implements Runnable {

    @Override
    public void run() {
      long start = System.nanoTime();
      long pingInterval = INITIAL_PING_INTERVAL;
      for(int iterationIdx=1;iterationIdx<MAX_ITERATIONS_PER_THREAD;iterationIdx++) {
          // Generate random keypair
        final KeyPair keyPair = new KeyPair();
        final BlockchainAddress address = keyPair.getPublic().createAddress();

        // Check vanity
        final String addressAsString = address.writeAsString();
        final boolean satisfiesVanity = addressAsString.startsWith(vanityPrefix) && addressAsString.endsWith(vanitySuffix);

        // Output if vain enough
        if(satisfiesVanity) {
          System.out.println("[%2d:%10d] match: addr=%s - pk=%s".formatted(threadIdx, iterationIdx, addressAsString, keyPair.getPrivateKey().toString(16)));
        }

        // Ping
        if (iterationIdx % pingInterval  == 0) {
          final long now = System.nanoTime();
          final long duration = (now - start) / 1_000_000_000;
          System.out.println("[%2d:%10d] ping at %d sec".formatted(threadIdx, iterationIdx, duration));
          pingInterval = pingInterval * 2;
        }
      }
    }
  }

}