const bitcoin = require("bitcoinjs-lib");
const reverse = require("buffer-reverse");

module.exports = async (req, res) => {
  let { user } = req;
  let { address, tx } = req.body;
  let { hex } = tx;

  let fee = toSats(tx.fee);

  const isChange = async address =>
    (await bc.getAddressInfo(address)).ismine &&
    (!Object.keys(addresses).includes(address) || address === user.address);

  tx = await bc.decodeRawTransaction(hex);

  let total = 0;
  let change = 0;

  for (let i = 0; i < tx.vout.length; i++) {
    let o = tx.vout[i];
    total += toSats(o.value);

    if (o.scriptPubKey.addresses) {
      if (await isChange(o.scriptPubKey.addresses[0])) {
        change += toSats(o.value);
      }
    }
  }

  total = total - change + fee;
  let amount = total - fee;

  l.info("attempting bitcoin payment", user.username, { total, change, amount, fee });

  let account, params;
  try {
    await db.transaction(async transaction => {
      account = await db.Account.findOne({
        where: {
          user_id: user.id,
          asset: config.liquid.btcasset
        },
        lock: transaction.LOCK.UPDATE,
        transaction
      });

      if (total > account.balance) {
        l.error("amount exceeds balance", amount, fee, account.balance);
        throw new Error("Insufficient funds");
      }

      account.balance -= total;
      await account.save({ transaction });

      params = {
        amount: -total,
        fee,
        account_id: account.id,
        user_id: user.id,
        rate: app.get("rates")[user.currency],
        currency: user.currency,
        address,
        confirmed: true,
        received: false,
        network: "BTC"
      };
    });
  } catch (e) {
    l.error("problem creating bitcoin payment", user.username, e.message);
    return res.status(500).send(e.message);
  }

  try {
    if (config.bitcoin.walletpass)
      await bc.walletPassphrase(config.bitcoin.walletpass, 300);

    hex = (await bc.signRawTransactionWithWallet(hex)).hex;
    params.hash = await bc.sendRawTransaction(hex);

    let payment = await db.Payment.create(params);

    user = await getUser(user.username);
    emit(user.username, "user", user);

    payment = payment.get({ plain: true });
    payment.account = account.get({ plain: true });
    res.send(payment);
    l.info("sent bitcoin", user.username, total);
  } catch (e) {
    l.error("error sending bitcoin", e.message);
    return res.status(500).send(e.message);
  }
};