import com.algorand.algosdk.account.Account;
import com.algorand.algosdk.crypto.Address;
import com.algorand.algosdk.kmd.client.ApiException;
import com.algorand.algosdk.kmd.client.KmdClient;
import com.algorand.algosdk.kmd.client.api.KmdApi;
import com.algorand.algosdk.kmd.client.model.*;
import com.algorand.algosdk.transaction.SignedTransaction;
import com.algorand.algosdk.transaction.Transaction;
import com.algorand.algosdk.util.Encoder;
import com.algorand.algosdk.v2.client.common.AlgodClient;
import com.algorand.algosdk.v2.client.common.IndexerClient;
import com.algorand.algosdk.v2.client.common.Response;
import com.algorand.algosdk.v2.client.model.PendingTransactionResponse;
import com.algorand.algosdk.v2.client.model.PostTransactionsResponse;
import com.algorand.algosdk.v2.client.model.TransactionsResponse;

import java.io.IOException;
import java.security.NoSuchAlgorithmException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

public class Main {
    private static String token = "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa";
    private static KmdApi kmd = null;

    public static void main(String[] args) throws Exception {
        // Initialize algod/indexer v2 clients.
        AlgodClient algod = new AlgodClient("http://localhost", 4001, token);
        IndexerClient indexer = new IndexerClient("http://localhost", 8980);

        // Initialize KMD v1 client
        KmdClient kmdClient = new KmdClient();
        kmdClient.setBasePath("http://localhost:4002");
        kmdClient.setApiKey(token);
        kmd = new KmdApi(kmdClient);

        // Get accounts from sandbox.
        String walletHandle = getDefaultWalletHandle();
        List<Address> accounts  = getWalletAccounts(walletHandle);

        // Create a payment transaction
        Transaction tx1 = Transaction.PaymentTransactionBuilder()
                .lookupParams(algod) // lookup fee, firstValid, lastValid
                .sender(accounts.get(0))
                .receiver(accounts.get(1))
                .amount(1000000)
                .noteUTF8("test transaction!")
                .build();

        // Sign with KMD
        SignedTransaction stx1a = signTransactionWithKMD(tx1, walletHandle);
        byte[] stx1aBytes = Encoder.encodeToMsgPack(stx1a);

        // Sign with private key
        byte[] privateKey = lookupPrivateKey(accounts.get(0), walletHandle);
        Account account = new Account(privateKey);
        SignedTransaction stx1b = account.signTransaction(tx1);
        byte[] stx1bBytes = Encoder.encodeToMsgPack(stx1b);

        // KMD and signing directly should both be the same.
        if (!Arrays.equals(stx1aBytes, stx1bBytes)) {
            throw new RuntimeException("KMD disagrees with the manual signature!");
        }

        // Send transaction
        Response<PostTransactionsResponse> post = algod.RawTransaction().rawtxn(stx1aBytes).execute();
        if (!post.isSuccessful()) {
            throw new RuntimeException("Failed to post transaction");
        }

        // Wait for confirmation
        boolean done = false;
        while (!done) {
            Response<PendingTransactionResponse> txInfo = algod.PendingTransactionInformation(post.body().txId).execute();
            if (!txInfo.isSuccessful()) {
                throw new RuntimeException("Failed to check on tx progress");
            }
            if (txInfo.body().confirmedRound != null) {
                done = true;
            }
        }

        // Wait for indexer to index the round.
        Thread.sleep(5000);

        // Query indexer for the transaction
        Response<TransactionsResponse> transactions = indexer.searchForTransactions()
                .txid(post.body().txId)
                .execute();

        if (!transactions.isSuccessful()) {
            throw new RuntimeException("Failed to lookup transaction");
        }

        System.out.println("Transaction received! \n" + transactions.toString());
    }

    public static SignedTransaction signTransactionWithKMD(Transaction tx, String walletHandle) throws IOException, ApiException {
        SignTransactionRequest req = new SignTransactionRequest();
        req.transaction(Encoder.encodeToMsgPack(tx));
        req.setWalletHandleToken(walletHandle);
        req.setWalletPassword("");
        byte[] stxBytes = kmd.signTransaction(req).getSignedTransaction();
        return Encoder.decodeFromMsgPack(stxBytes, SignedTransaction.class);
    }

    public static byte[] lookupPrivateKey(Address addr, String walletHandle) throws ApiException {
        ExportKeyRequest req = new ExportKeyRequest();
        req.setAddress(addr.toString());
        req.setWalletHandleToken(walletHandle);
        req.setWalletPassword("");
        return kmd.exportKey(req).getPrivateKey();
    }

    public static String getDefaultWalletHandle() throws ApiException {
        for (APIV1Wallet w : kmd.listWallets().getWallets()) {
            if (w.getName().equals("unencrypted-default-wallet")) {
                InitWalletHandleTokenRequest tokenreq = new InitWalletHandleTokenRequest();
                tokenreq.setWalletId(w.getId());
                tokenreq.setWalletPassword("");
                return kmd.initWalletHandleToken(tokenreq).getWalletHandleToken();
            }
        }
        throw new RuntimeException("Default wallet not found.");
    }

    public static List<Address> getWalletAccounts(String walletHandle) throws ApiException, NoSuchAlgorithmException {
        List<Address> accounts = new ArrayList<>();

        ListKeysRequest keysRequest = new ListKeysRequest();
        keysRequest.setWalletHandleToken(walletHandle);
        for (String addr : kmd.listKeysInWallet(keysRequest).getAddresses()) {
            accounts.add(new Address(addr));
        }

        return accounts;
    }
}