Add colors

Add color supports and the -c and -b options.

README.md

@@ -4,7 +4,14 @@ Dutch woordklok, written in go.
 
 ## Usage
 
-    ./woordklok
+The program applies colors if it is run within a tty. To explicitly use colors use `-c`, to never use colors use the batch mode `-b`
+
+    $ ./woordklok
+    HETknISadvzVIJFtiengkwartbOVERvoormhalfyachtweezesdrielftienxzeveNEGENviertwaalfeenvijfUUR
+
+Give a list of all available options with
+
+    ./woordklok -h            # Display help message
 
 ## Building
 

woordklok.go

@@ -1,23 +1,26 @@
 package main
 
 import (
+	"flag"
 	"fmt"
+	"os"
 	"strings"
 	"time"
 )
 
 // Replace occurences of repl with their uppercase in str
-func repl_upper(str string, repl []string) string {
+func replace(str string, repl []string, prefix string, suffix string) string {
 	ret := str
 	for _, r := range repl {
-		ret = strings.ReplaceAll(ret, r, strings.ToUpper(r))
+		rx := fmt.Sprintf("%s%s%s", prefix, strings.ToUpper(r), suffix)
+		ret = strings.ReplaceAll(ret, r, rx)
 	}
 	return ret
 }
 
-func woordklok(tsp time.Time) string {
+func woordklok(tsp time.Time, color bool) string {
 	// minutes part
-	klok1 := "HETknISadvzvijftiengkwartbovervoormhalf"
+	klok1 := "hetknisadvzvijftiengkwartbovervoormhalf"
 	// hours
 	klok2 := "yachtweezesdrielftienxzevenegenviertwaalfeenvijfuur"
 
@@ -25,30 +28,32 @@ func woordklok(tsp time.Time) string {
 	hh := tsp.Hour() % 12
 
 	// get the matching text
-	m := "uur"
+	m := "het is "
 	if mm >= 55 {
-		m = "vijf voor"
+		m += "vijf voor"
 	} else if mm >= 50 {
-		m = "tien voor"
+		m += "tien voor"
 	} else if mm >= 45 {
-		m = "kwart voor"
+		m += "kwart voor"
 	} else if mm >= 40 {
-		m = "tien over half"
+		m += "tien over half"
 	} else if mm >= 35 {
-		m = "vijf over half"
+		m += "vijf over half"
 	} else if mm >= 30 {
-		m = "half"
+		m += "half"
 	} else if mm >= 25 {
-		m = "vijf voor half"
+		m += "vijf voor half"
 	} else if mm >= 20 {
-		m = "tien voor half"
+		m += "tien voor half"
 		hh++
 	} else if mm >= 15 {
-		m = "kwart over"
+		m += "kwart over"
 	} else if mm >= 10 {
-		m = "tien over"
+		m += "tien over"
 	} else if mm >= 5 {
-		m = "vijf over"
+		m += "vijf over"
+	} else {
+		m += " uur"
 	}
 
 	hours := []string{
@@ -65,13 +70,41 @@ func woordklok(tsp time.Time) string {
 		"tien",
 		"elf",
 	}
-	hour := hours[hh]
+	hour := hours[hh] + " uur"
 
 	// and replace the matching text with the uppercase
-	return fmt.Sprintf("%s%s", repl_upper(klok1, strings.Split(m, " ")), repl_upper(klok2, strings.Split(hour, " ")))
+	prefix := ""
+	suffix := ""
+	if color {
+		// Add color definitions
+		prefix = "\u001b[32m" // ANSI green
+		suffix = "\u001b[0m"  // ANSI reset
+	}
+	return fmt.Sprintf("%s%s", replace(klok1, strings.Split(m, " "), prefix, suffix), replace(klok2, strings.Split(hour, " "), prefix, suffix))
+}
+
+func IsTTY() bool {
+	if fileInfo, _ := os.Stdout.Stat(); (fileInfo.Mode() & os.ModeCharDevice) != 0 {
+		return true
+	} else {
+		return false
+	}
 }
 
 func main() {
-	woord := woordklok(time.Now())
+	color := flag.Bool("c", false, "Always use colors")
+	batch := flag.Bool("b", false, "Batch mode (no colors)")
+	flag.Parse()
+
+	// Determine if you
+	colors := *color
+	if !colors {
+		colors = IsTTY()
+	}
+	if *batch {
+		colors = false
+	}
+
+	woord := woordklok(time.Now(), colors)
 	fmt.Println(woord)
 }