const assert = require('assert')
const Kraken = require('kraken-api')

const {
  KRAKEN_API_KEY: key,
  KRAKEN_API_SECRET: secret,
  KRAKEN_MAX_REL_FEE: max_fee,
  KRAKEN_WITHDRAW_KEY: wdr_key
} = process.env

assert(key && secret, 'Provide the KRAKEN_API_KEY and KRAKEN_API_SECRET environment variables.')
assert(max_fee && wdr_key, 'Provide the KRAKEN_MAX_REL_FEE and KRAKEN_WITHDRAW_KEY environment variables.')

// https://www.kraken.com/features/api
const kraken = new Kraken(key, secret)
const crypto = 'XBT'
const validate = process.argv[2] === '--validate'

;(async () => {
    // Get withdrawal information
    // URL: https://api.kraken.com/0/private/WithdrawInfo
    const withdrawdetails = { asset: crypto, key: wdr_key, amount: 0 } 
    try {
        const { result: { method, limit, fee } } = await kraken.api('WithdrawInfo', withdrawdetails);
        const rel_fee = 1/parseFloat(limit)*parseFloat(fee)
        console.log(`💡  Relative fee of withdrawal amount: ${(rel_fee*100).toFixed(2)}%`)

        // Place withdrawal when fee is low enough (relatively)
        if (rel_fee < max_fee/100) {
            console.log(`⏏️  Withdraw ${limit} ${crypto} now.`)
            const withdraw = { asset: crypto, key: wdr_key, amount: limit } 
            if (!validate) {
                try {
                    const { result: { refid } } = await kraken.api('Withdraw', withdraw)
                    if (refid) console.log(`📎  Withdrawal reference ID: ${refid}`)
                } catch (err) {
                    console.log(`\n🚨  Failure:`, err.message)
                }
            }
        }else{
            console.log(`\n❌ Don\'t withdraw now. Fee is too high. Max rel. fee: ${parseFloat(max_fee).toFixed(2)}%`);
        }
    } catch (err) {
        console.log(`\n🚨  Failure:`, err.message)
    }
    if (validate) console.log('\n🚨  THIS WAS JUST A VALIDATION RUN, NO WITHDRAWAL HAS BEEN PLACED!')
})()