utils.js

import ethJsTx from 'ethereumjs-tx'
const LOG = require('./transaction-loggers')

/**
 * Note - Most values are hex's of the actual value
 * {"nonce":"0x10", // # historical transactions by sender address
 * "gasPrice":"0x04e3b29200", // 21000 ? etermined by the x latest blocks median gas price. 20gwei or 20000000000 // recently 9 000 000 000
 * "gasLimit":"0x5208", // # formerly 21000 to send on MEW or 300000 here // "amount of gas you pay is fixed, but the quantity of ethere it costs for that is not fixed (it varies)" // wont necessarily use all of this limit? e.g. if set a super high limit...
 * "to":"0x1eec5a83f78d3952fe86747034a7514f2dc9925c", // address of recipient
 * "value":"0x2386f26fc10000", // eventually // eventually hex(web3.utils.toWei(value.toString(),'ether'))
 * "data":"", // only for deploying smart contract
 * "chainId":1}
 */
// Make web3 calls to get data for Raw Transaction object tx
export async function createRawTransaction (web3, ether, recipient) {
    const gasPrice = web3.eth.gasPrice; // gasPrice.toString(10)) "10000000000000"
    const txCount = web3.eth.getTransactionCount(process.env.fromAddress)
    var gasLimit = web3.eth.getBlock("latest").gasLimit

    const wei = LOG.weiAmountBeingSent(ether)

    const rawTx = {
        nonce: hex(txCount, web3),
        gas: hex("21000", web3),
        gasPrice: hex(web3.toWei('10', 'gwei'), web3),
        to: recipient,
        value: hex(wei, web3)
    }
    LOG.gasPriceInEther(gasPrice, web3)      
    LOG.rawTxData({nonce: txCount, gasPrice, gasLimit, to: recipient, value: ether, chainId: process.env.chainId, data: ""}, rawTx)
    
    return new ethJsTx(rawTx) // Transaction: { raw: [<Buffer >], _fields: ['nonce',]}  
}

export function createSignedSerializedTransaction (transaction, pKey) {
    // TODO - generate address from privateKey and make sure it matches what's in process.env.address or else wrong nonce might get used
    const privateKey = Buffer.from(pKey, 'hex')
    transaction.sign(privateKey)
    const txSerialized = transaction.serialize() // <Buffer f8 ...>
    return txSerialized
}

function hex (number, web3) {
    return web3.toHex(number)
}