Add hourly rain forecast sparklines (#39)

Updates #38

forecast/print.go

@@ -1,6 +1,7 @@
 package forecast
 
 import (
+	"bytes"
 	"fmt"
 	"math"
 	"strings"
@@ -75,6 +76,16 @@ func epochFormatTime(seconds int64) string {
 	return epochTime.Format("3:04pm MST")
 }
 
+func epochFormatHour(seconds int64) string {
+	epochTime := time.Unix(0, seconds*int64(time.Second))
+	s := epochTime.Format("3pm")
+	s = s[:len(s)-1]
+	if len(s) == 2 {
+		s += " "
+	}
+	return s
+}
+
 func getIcon(iconStr string) (icon string, err error) {
 	color := "blue"
 	// steralize the icon string name
@@ -220,7 +231,38 @@ func PrintCurrent(forecast Forecast, geolocation geocode.Geocode, ignoreAlerts b
 		}
 	}
 
-	return printCommon(forecast.Currently, unitsFormat)
+	if err := printCommon(forecast.Currently, unitsFormat); err != nil {
+		return err
+	}
+
+	if forecast.Hourly.Summary != "" {
+		fmt.Printf("%s\n\n", forecast.Hourly.Summary)
+
+		var ticks = []rune(" ▁▂▃▄▅▆▇█")
+		rainForecast, showRain := &bytes.Buffer{}, false
+		for i := 0; i < 16; i++ {
+			p := forecast.Hourly.Data[i].PrecipProbability
+			t := int(p*float64(len(ticks)-2)) + 1
+			if p == 0 {
+				t = 0
+			} else {
+				showRain = true
+			}
+			rainForecast.WriteRune(ticks[t])
+			rainForecast.WriteRune(ticks[t])
+			rainForecast.WriteRune(' ')
+		}
+		if showRain {
+			fmt.Printf("Rain chance: %s\n", rainForecast)
+			fmt.Printf("             ")
+			for i := 0; i < 4; i++ {
+				fmt.Printf("%s         ", epochFormatHour(forecast.Hourly.Data[i*4].Time))
+			}
+			fmt.Printf("\n\n")
+		}
+	}
+
+	return nil
 }
 
 // PrintDaily pretty prints the daily forecast data.

main.go

@@ -23,6 +23,7 @@ var (
 	days         int
 	ignoreAlerts bool
 	hideIcon     bool
+	noForecast   bool
 	server       string
 	vrsn         bool
 	client       bool
@@ -50,6 +51,7 @@ func init() {
 	flag.IntVar(&days, "d", 0, "No. of days to get forecast (shorthand)")
 	flag.BoolVar(&ignoreAlerts, "ignore-alerts", false, "Ignore alerts in weather output")
 	flag.BoolVar(&hideIcon, "hide-icon", false, "Hide the weather icons from being output")
+	flag.BoolVar(&noForecast, "no-forecast", false, "Hide the forecast for the next 16 hourse")
 
 	flag.Usage = func() {
 		flag.PrintDefaults()
@@ -108,7 +110,10 @@ func main() {
 		Latitude:  geo.Latitude,
 		Longitude: geo.Longitude,
 		Units:     units,
-		Exclude:   []string{"hourly", "minutely"},
+		Exclude:   []string{"minutely"},
+	}
+	if noForecast {
+		data.Exclude = append(data.Exclude, "hourly")
 	}
 
 	fc, err := forecast.Get(fmt.Sprintf("%s/forecast", server), data)