import * as StellarSdk from 'stellar-sdk';

const sourceKey = StellarSdk.Keypair.random(); // $ExpectType Keypair
const destKey = StellarSdk.Keypair.random();
const account = new StellarSdk.Account(sourceKey.publicKey(), '1');
const transaction = new StellarSdk.TransactionBuilder(account)
    .addOperation(StellarSdk.Operation.accountMerge({destination: destKey.publicKey()}))
    .addMemo(new StellarSdk.Memo(StellarSdk.MemoText, "memo"))
    .build(); // $ExpectType () => Transaction
transaction; // $ExpectType Transaction

StellarSdk.StellarTomlResolver.resolve("example.com", {allowHttp: true, timeout: 100})
    .then(toml => toml.FEDERATION_SERVER);

const sig = StellarSdk.xdr.DecoratedSignature.fromXDR(Buffer.of(1, 2)); // $ExpectType DecoratedSignature
sig.hint(); // $ExpectType Buffer
sig.signature(); // $ExpectType Buffer

StellarSdk.Memo.none(); // $ExpectType Memo<"none">
StellarSdk.Memo.text('asdf'); // $ExpectType Memo<"text">
StellarSdk.Memo.id('asdf'); // $ExpectType Memo<"id">
StellarSdk.Memo.return('asdf'); // $ExpectType Memo<"return">
StellarSdk.Memo.hash('asdf'); // $ExpectType Memo<"hash">
StellarSdk.Memo.none().value; // $ExpectType null
StellarSdk.Memo.id('asdf').value; // $ExpectType string
StellarSdk.Memo.text('asdf').value; // $ExpectType string
StellarSdk.Memo.return('asdf').value; // $ExpectType Buffer
StellarSdk.Memo.hash('asdf').value; // $ExpectType Buffer

// P.S. don't use Memo constructor
(new StellarSdk.Memo(StellarSdk.MemoHash, 'asdf')).value; // $ExpectType AnyValue

    return co(function *() {
      const [userKey, backupKey] = this.initiateRecovery(params);
      const isKrsRecovery = params.backupKey.startsWith('G') && !params.userKey.startsWith('G');
      const isUnsignedSweep = params.backupKey.startsWith('G') && params.userKey.startsWith('G');

      if (!stellar.StrKey.isValidEd25519PublicKey(params.rootAddress)) {
        throw new Error(`Invalid wallet address: ${ params.rootAddress }`);
      }

      const accountDataUrl = `${ this.getHorizonUrl() }/accounts/${ params.rootAddress }`;
      const destinationUrl = `${ this.getHorizonUrl() }/accounts/${ params.recoveryDestination }`;

      let accountData;
      try {
        accountData = yield request.get(accountDataUrl).result();
      } catch (e) {
        throw new Error('Unable to reach the Stellar network via Horizon.');
      }

      // Now check if the destination account is empty or not
      let unfundedDestination = false;
      try {
        yield request.get(destinationUrl);
      } catch (e) {
        if (e.status === 404) {
          // If the destination account does not yet exist, horizon responds with 404
          unfundedDestination = true;
        }
      }

      if (!accountData.sequence || !accountData.balances) {
        throw new Error('Horizon server error - unable to retrieve sequence ID or account balance');
      }

      const account = new stellar.Account(params.rootAddress, accountData.sequence);

      // Stellar supports multiple assets on chain, we're only interested in the balances entry whose type is "native" (XLM)
      const nativeBalanceInfo = accountData.balances.find(assetBalance => assetBalance['asset_type'] === 'native');

      if (!nativeBalanceInfo) {
        throw new Error('Provided wallet has a balance of 0 XLM, recovery aborted');
      }

      const walletBalance = this.bigUnitsToBaseUnits(nativeBalanceInfo.balance);
      const minimumReserve = yield this.getMinimumReserve();
      const baseTxFee = yield this.getBaseTransactionFee();
      const recoveryAmount = walletBalance - minimumReserve - baseTxFee;
      const formattedRecoveryAmount = (this.baseUnitsToBigUnits(recoveryAmount)).toString();

      let txBuilder = new stellar.TransactionBuilder(account);
      let operation;
      if (unfundedDestination) { // In this case, we need to create the account
        operation = stellar.Operation.createAccount({
          destination: params.recoveryDestination,
          startingBalance: formattedRecoveryAmount
        });
      } else { // Otherwise if the account already exists, we do a normal send
        operation = stellar.Operation.payment({
          destination: params.recoveryDestination,
          asset: stellar.Asset.native(),
          amount: formattedRecoveryAmount
        });
      }
      txBuilder = txBuilder.addOperation(operation).build();

      if (!isUnsignedSweep) {
        txBuilder.sign(userKey);
      }

      if (!isKrsRecovery && !isUnsignedSweep) {
        txBuilder.sign(backupKey);
      }

      const transaction: any = {
        tx: txBuilder.toEnvelope().toXDR('base64'),
        recoveryAmount
      };

      if (isKrsRecovery) {
        transaction.backupKey = params.backupKey;
        transaction.coin = this.getChain();
      }

      return transaction;
    }).call(this);