Exchange transactions example

import { AddExchangeOfferTransaction, ExchangeOfferTransaction, 
    RemoveExchangeOfferTransaction, Deadline, Account, NetworkType, AddExchangeOffer, 
    ExchangeOffer, RemoveExchangeOffer, UInt64, ExchangeOfferType, MosaicId, MosaicNonce 
} from 'tsjs-xpx-chain-sdk';
import { Network } from '../utils';

const network = new Network('http://localhost:3000');

const alice = Account.createFromPrivateKey(
    'c6f77df1c55b84a7673561eb221c282edb8d9a3f4d66f9320b85736d2e3cdeda',
    NetworkType.MIJIN_TEST, 1);

const aliceMosaicId = new MosaicId([
    3205233868,
    173793843
]);

const bob = Account.createFromPrivateKey(
    '7ad5e23f2e71e7a470deaa0f4f85c414ff915d8a670a598c6600c461b72e9f18',
    NetworkType.MIJIN_TEST, 1);


// SELL OFFER

// alice offers some mosaic she owns for sale
const addExchangeSellOffer = () => {
    const offers = [
        new AddExchangeOffer(
            aliceMosaicId,                // mosaic
            UInt64.fromUint(10000000),    // amount of mosaic
            UInt64.fromUint(10000000),    // asked price per amount in xpx
            ExchangeOfferType.SELL_OFFER, // alice is selling
            UInt64.fromUint(1000)         // duration of the offer - number of blocks
        )
    ];
    const tx = AddExchangeOfferTransaction.create(
        Deadline.create(),
        offers,
        NetworkType.MIJIN_TEST
    );
    return network.networkProperties.then(networkProperties => {
        const signedTx = alice.preV2Sign(tx, networkProperties.generationHash);
        return network.announceAndWaitForConfirmation(signedTx).then(tx => {
            console.log('Confirmed:');
            console.log(tx);
        });
    });
};

// bob can try to buy some mosaic from alice
const exchangeSellOffer = () => {
    const offers = [
        new ExchangeOffer(
            aliceMosaicId,                 // mosaic
            UInt64.fromUint(100),          // amount of mosaic
            UInt64.fromUint(100),          // proposed price per amount in xpx
            ExchangeOfferType.SELL_OFFER,  // alice is selling
            alice.publicAccount            // from alice
        )
    ];
    const tx = ExchangeOfferTransaction.create(
        Deadline.create(),
        offers,
        NetworkType.MIJIN_TEST
    );
    return network.networkProperties.then(networkProperties => {
        const signedTx = bob.preV2Sign(tx, networkProperties.generationHash);
        return network.announceAndWaitForConfirmation(signedTx).then(tx => {
            console.log('Confirmed:');
            console.log(tx);
        });
    });
};

// alice can cancel unmatched rest of the published sell offer
const removeExchangeSellOffer = () => {
    const removeOffers = [
        new RemoveExchangeOffer(
            aliceMosaicId,                 // mosaic
            ExchangeOfferType.SELL_OFFER,  // alice is selling
        )
    ];
    const tx = RemoveExchangeOfferTransaction.create(
        Deadline.create(),
        removeOffers,
        NetworkType.MIJIN_TEST
    );
    return network.networkProperties.then(networkProperties => {
        const signedTx = alice.preV2Sign(tx, networkProperties.generationHash);
        return network.announceAndWaitForConfirmation(signedTx).then(tx => {
            console.log('Confirmed:');
            console.log(tx);
        });
    });
};

// or,
// BUY OFFER

// bob advertises his interest in some mosaic
const addExchangeBuyOffer = () => {
    const offers = [
        new AddExchangeOffer(
            aliceMosaicId,                 // mosaic
            UInt64.fromUint(10000000),     // amount of mosaic
            UInt64.fromUint(10000000),     // proposed price per amount in xpx
            ExchangeOfferType.BUY_OFFER,   // bob is buying
            UInt64.fromUint(1000)          // duration of the offer - number of blocks
        )
    ];
    const tx = AddExchangeOfferTransaction.create(
        Deadline.create(),
        offers,
        NetworkType.MIJIN_TEST
    );

    return network.networkProperties.then(networkProperties => {
        const signedTx = bob.preV2Sign(tx, networkProperties.generationHash);
        return network.announceAndWaitForConfirmation(signedTx).then(tx => {
            console.log('Confirmed:');
            console.log(tx);
        });
    });
};

// alice can try to offer some to bob
const exchangeBuyOffer = () => {
    const offers = [
        new ExchangeOffer(
            aliceMosaicId,                 // mosaic
            UInt64.fromUint(100),          // amount of mosaic
            UInt64.fromUint(100),          // asked price per amount in xpx
            ExchangeOfferType.BUY_OFFER,   // bob is buying
            bob.publicAccount              // to bob
        )
    ];
    const tx = ExchangeOfferTransaction.create(
        Deadline.create(),
        offers,
        NetworkType.MIJIN_TEST
    );
    return network.networkProperties.then(networkProperties => {
        const signedTx = alice.preV2Sign(tx, networkProperties.generationHash);
        return network.announceAndWaitForConfirmation(signedTx).then(tx => {
            console.log('Confirmed:');
            console.log(tx);
        });
    });
};

// bob can cancel unmatched rest of the published buy offer
const removeExchangeBuyOffer = () => {
    const removeOffers = [
        new RemoveExchangeOffer(
            aliceMosaicId,                 // mosaic
            ExchangeOfferType.BUY_OFFER,   // bob is buying
        )
    ];
    const tx = RemoveExchangeOfferTransaction.create(
        Deadline.create(),
        removeOffers,
        NetworkType.MIJIN_TEST
    );
    return network.networkProperties.then(networkProperties => {
        const signedTx = bob.preV2Sign(tx, networkProperties.generationHash);
        return network.announceAndWaitForConfirmation(signedTx).then(tx => {
            console.log('Confirmed:');
            console.log(tx);
        });
    });
};

addExchangeSellOffer().then(_ => {
    exchangeSellOffer().then(_ => {
        removeExchangeSellOffer().then(_ => {
            addExchangeBuyOffer().then(_ => {
                exchangeBuyOffer().then(_ => {
                    removeExchangeBuyOffer().then(_ => {
                        console.log('All done.');
                    });
                });
            });
        });
    });
});