/*
2020-01-09 - get the gains generated by my automated ETC trading.
2020-10-23 - fix problem because API requires windowing to handle more than 50 rows, implemented windowing.
2020-12-02 - change to persist transactions and handle pairs as provided by commandline parameter.
2020-12-04 - handle commandline inlcuding verbosity of output.
*/

const yargs = require('yargs/yargs')
const { hideBin } = require('yargs/helpers')
const argv = yargs(hideBin(process.argv)).argv


const key          = 'SOOOJ7OhVCOpJE4DAWz8v5B25UpdYya9buF8DFAkHzmUab5E9i0PlEPh'; // API Key
const secret       = 'UytAbgU8ty3n5a+JhaoIlcfh8zM4OBGY6PCC+Cfg2NI4waVzM52BBp9qmmyczrTDQpeha8q3nHeE/p7wNWKiVA=='; // API Private Key
const KrakenClient = require('kraken-api');
const kraken       = new KrakenClient(key, secret);
const fs           = require('fs')

const storeData = (data, path) => {
	try {
		fs.writeFileSync(path, JSON.stringify(data));
	} catch (err) {
		console.error("error in storeData ",err);
	}
}

const loadData = (path) => {
	try {
		return JSON.parse(fs.readFileSync(path, 'utf8'));
	} catch (err) {
		console.error("error in loadData ",err);
		return false;
	}
}

const utcToLocal = (utc) => {
	return new Date(utc.getTime() - (utc.getTimezoneOffset() * 60000));
}

(async () => {
	try {		
		// get the pair to process from the first parameter and fall back if not provided.
		let thePair=argv.pair;
		if (thePair===undefined) {
			thePair="XXMRZUSD";
		}
		thePair=thePair.toUpperCase(); // the pairs are always upper case.	
		console.log("Processing pair			: ", thePair);

		let dataFile = argv.dataFile;
		if (dataFile===undefined) {
			dataFile = "allTrades.json";
		}
		let allTrades=loadData(dataFile);
		let params={ ofs : 0 };
		let maxTimestamp=0;
		allTrades.forEach(dta=>{if (dta.time>maxTimestamp) {maxTimestamp=dta.time;} });
		params.start=maxTimestamp;
		console.log("Max-Timestamp			: ",maxTimestamp);			
		
		if (!argv.skipRequestTrades) {
			let allTransactions = await kraken.api('TradesHistory', params);
			let allTradeIDs=Object.keys(allTransactions.result.trades);
			let numTrans=allTradeIDs.length;

			console.log("Number of new Transactions	: ",numTrans);
			for (let i=0;i<numTrans;i++){
				params.ofs+=1;
				let theTrade=allTransactions.result.trades[allTradeIDs[i]];
				
				// the timestamp is inclusive, therefore we have to skip that record.
				if (theTrade.time === maxTimestamp) { continue; } 
				if (argv.v) { console.log(theTrade); }
			
				allTrades.push(theTrade);
				if ((params.ofs % 50) == 0) { 
					console.log("Load more results; offset ",params.ofs);
					params.nonce = new Date() * 1000;
					allTransactions = await kraken.api('TradesHistory', params);
					allTradeIDs=allTradeIDs.concat(Object.keys(allTransactions.result.trades));
					numTrans=allTradeIDs.length; // Not really great style to update the for condition var here, but it works...
				}
			}

			// sort the trades by time; oldest first.
			allTrades=allTrades.sort(function (a,b){return(a.time - b.time);});
			storeData(allTrades,dataFile);
		}
		
		let sumUSD=0;
		let sumCommission=0;
		let numTrades=0;
		for (let i=0;i<allTrades.length;i++){
			let theTrade=allTrades[i];
			if (theTrade.pair===thePair) {
				numTrades++;
				
				let tradeLocalTime=utcToLocal(new Date(theTrade.time * 1000)).toISOString().substr(0,19).replace('T',' ');
				if (argv.v) {console.log(`${tradeLocalTime} [${theTrade.pair}] ${theTrade.type.substring(0,1)}#${Number(theTrade.vol).toFixed(4).padStart(10," ")}@${Number(theTrade.price).toFixed(2).padStart(8," ")} -> ${Number(theTrade.cost).toFixed(2).padStart(9," ")}(-${Number(theTrade.fee).toFixed(3).padStart(5," ")})`);}
				
				// selling adds $$$ to our Account, buying takes money out of the account
				let multiplier=theTrade.type==="buy"?-1:1;

				sumUSD += Number(theTrade.cost) * multiplier;
				sumCommission += Number(theTrade.fee);
			}
		}

		let allBalances=await kraken.api('Balance');
		let pairQuote = await kraken.api('Ticker', { pair : thePair });

		// find the currency by looking for "startsWith" type match in the symbol in the pair.
		// (not sure if that always works, but it works for all cases I checked it so far).
		let theCurrency=undefined;
		Object.keys(allBalances.result).forEach((currency)=>{
			if (thePair.indexOf(currency)===0) {
				theCurrency=currency;
			}
		});

		console.log("# trades               		: ", numTrades);
		console.log("SUM USD                		: ", sumUSD);
		console.log("SUM fees               		: ", sumCommission);
		let netGain = sumUSD - sumCommission;
		console.log("Net Gain               		: ", netGain);				
		let numCoinsHeld = Number(allBalances.result[theCurrency]);
		console.log("# coins Held           		: ", numCoinsHeld, " [", theCurrency,"]");
		let sellPrice = Number(pairQuote.result[thePair].b[0]);
		console.log("Current Price          		: ", sellPrice);
		let worthHeldCoins = numCoinsHeld * sellPrice;
		console.log("Worth held coins       		: ", worthHeldCoins);
		let netLiq = netGain + worthHeldCoins;
		console.log("Net Liquidation Gain   		: " , netLiq);
	} catch (ex) {
		console.error("General Error: ", ex.message, "\n", ex.stack);
	}
})();