Fixes to portfolio cost/profit

cointop/conversion.go

@@ -12,7 +12,7 @@ import (
 	log "github.com/sirupsen/logrus"
 )
 
-// FiatCurrencyNames is a mpa of currency symbols to names.
+// FiatCurrencyNames is a map of currency symbols to names.
 // Keep these in alphabetical order.
 var FiatCurrencyNames = map[string]string{
 	"AUD": "Australian Dollar",
@@ -301,3 +301,23 @@ func CurrencySymbol(currency string) string {
 
 	return "?"
 }
+
+func (ct *Cointop) Convert(convertFrom string, convertTo string, amount float64) (float64, error) {
+	convertFrom = strings.ToLower(convertFrom)
+	convertTo = strings.ToLower(convertTo)
+
+	var rate float64
+	if convertFrom == convertTo {
+		rate = 1.0
+	} else if convertFrom == "usd" && convertTo == "aud" {
+		rate = 1.33 // TODO: cache exchange rates and remove this dodgy hack
+		log.Debugf("XXX DODGY HACK Convert(%s, %s, %f) = %f", convertFrom, convertTo, amount, rate*amount)
+	} else {
+		crate, err := ct.api.GetExchangeRate(convertFrom, convertTo)
+		if err != nil {
+			return 0, err
+		}
+		rate = crate
+	}
+	return rate * amount, nil
+}

cointop/portfolio.go

@@ -341,13 +341,16 @@ func (ct *Cointop) GetPortfolioTable() *table.Table {
 						Text:        text,
 					})
 			case "profit":
-				// TODO: finish
 				text := ""
 				if coin.BuyPrice > 0 && coin.BuyCurrency != "" {
-					// TODO: currency conversion
-					profit := coin.Holdings * (coin.Price - coin.BuyPrice)
-					profit = math.Round(100*profit) / 100 // cheesy round
-					text = ct.FormatPrice(profit)
+					costPrice, err := ct.Convert(coin.BuyCurrency, ct.State.currencyConversion, coin.BuyPrice)
+					if err == nil {
+						profit := (coin.Price - costPrice) * coin.Holdings
+						profit = math.Round(100*profit) / 100 // cheesy round
+						text = ct.FormatPrice(profit)
+					} else {
+						text = "?"
+					}
 				}
 				if ct.State.hidePortfolioBalances {
 					text = HiddenBalanceChars
@@ -366,10 +369,11 @@ func (ct *Cointop) GetPortfolioTable() *table.Table {
 			case "profit_percent":
 				profitPercent := 0.0
 				if coin.BuyPrice > 0 && coin.BuyCurrency != "" {
-					// TODO: currency conversion
-					profitPercent = 100 * (coin.Price/coin.BuyPrice - 1)
+					costPrice, err := ct.Convert(coin.BuyCurrency, ct.State.currencyConversion, coin.BuyPrice)
+					if err == nil {
+						profitPercent = 100 * (coin.Price/costPrice - 1)
+					}
 				}
-				// text = ct.FormatPrice(profit)
 				colorProfit := ct.colorscheme.TableColumnChange
 				if profitPercent > 0 {
 					colorProfit = ct.colorscheme.TableColumnChangeUp

pkg/api/impl/coinmarketcap/coinmarketcap.go

@@ -430,3 +430,11 @@ func getChartInterval(start, end int64) string {
 	}
 	return interval
 }
+
+// GetExchangeRate gets the current excange rate between two currencies
+func (s *Service) GetExchangeRate(convertFrom string, convertTo string) (float64, error) {
+	if convertFrom == convertTo {
+		return 1.0, nil
+	}
+	return 0, fmt.Errorf("unsupported currency conversion: %s => %s", convertFrom, convertTo)
+}

pkg/api/interface.go

@@ -16,4 +16,5 @@ type Interface interface {
 	CoinLink(name string) string
 	SupportedCurrencies() []string
 	Price(name string, convert string) (float64, error)
+	GetExchangeRate(convertFrom string, convertTo string) (float64, error)
 }