Added cointoss functionality and some more formatting

dice-roller.1

@@ -13,6 +13,9 @@ dice-roller \- Dice roller utility written in GO
 .PP
 .B dice-roller
 .OP --disadvantage
+.PP
+.B dice-roller
+.OP --coin
 .SH DESCRIPTION
 .B dice-roller
 is a little dice roller I wrote because I'm hopelessly bad at basic arithmetic equations.
@@ -36,3 +39,6 @@ Roll two 2d20 and take the highest number, accepts modifiers
 .TP
 .B --disadvantage
 Roll two 2d20 and take the lowest number, accepts modifiers
+.TP
+.B --coin
+Toss a coin, same behaviour as throwing with 2 surfaces, only accepts different amount of casts.

main.go

@@ -5,12 +5,13 @@ import (
 	"fmt"
 	"math/rand"
 	"os"
+	"strings"
 	"time"
 )
 
 var (
 	surfaces, modifier, diceThrows, attacks int
-	advantage, disadvantage                 bool
+	advantage, disadvantage, coin           bool
 )
 
 type Color string
@@ -31,8 +32,26 @@ func main() {
 	ParseFlags()
 
 	switch {
+
+	// few basic checks
+	case attacks < 1:
+		fmt.Println("Attack amount cannot be below 1")
+		os.Exit(1)
+
+	case surfaces < 2:
+		fmt.Println("Die surfaces cannot be below 2")
+		os.Exit(1)
+
+	case diceThrows < 1:
+		fmt.Println("Dice thrown cannot be below 1")
+		os.Exit(1)
+
+	// die with 2 sides might as well be a coin
+	case surfaces == 2 || coin:
+		TossCoin(diceThrows)
+
 	case advantage:
-		if modifier != 0 {
+		if modifier > 0 {
 			fmt.Printf("%sRolling 1d20 + %d with advantage...%s\n", Color(ColorGreen), modifier, Color(ColorReset))
 		} else {
 			fmt.Printf("%sRolling 1d20 with advantage...%s\n", Color(ColorGreen), Color(ColorReset))
@@ -47,10 +66,6 @@ func main() {
 		}
 		fmt.Printf("\t%s%d%s\n", Color(ColorRed), Disadvantage(SimpleCast(), SimpleCast()), Color(ColorReset))
 
-	case attacks < 1:
-		fmt.Println("Attack amount cannot be below 1")
-		os.Exit(1)
-
 	case attacks > 1:
 		for i := 0; i < attacks; i++ {
 			fmt.Printf("%sAttack %d:%s\n", Color(ColorBlue), i+1, Color(ColorReset))
@@ -77,9 +92,34 @@ func ParseFlags() {
 	flag.BoolVar(&advantage, "advantage", false, "Roll with advantage")
 	flag.BoolVar(&disadvantage, "disadvantage", false, "Roll with disadvantage")
 
+	flag.BoolVar(&coin, "coin", false, "Toss a coin, same as '-s 2'")
+
 	flag.Parse()
 }
 
+func TossCoin(castAmount int) {
+	var (
+		coins     []string
+		coin      string
+		coinState int
+	)
+	for i := 0; i < castAmount; i++ {
+		coinState = rand.Intn(2)
+		if coinState == 0 {
+			coin = ColorYellow + "heads" + ColorReset
+		} else {
+			coin = ColorBlue + "tails" + ColorReset
+		}
+		coins = append(coins, coin)
+	}
+	if castAmount > 1 {
+		fmt.Printf("%sTossing %d coins...%s\n", ColorYellow, castAmount, ColorReset)
+	} else {
+		fmt.Printf("%sTossing coin...%s\n", ColorYellow, ColorReset)
+	}
+	fmt.Printf("\t%s\n", strings.Trim(fmt.Sprint(coins), "[]"))
+}
+
 func Cast(dieSurfaces, castAmount int) {
 	var (
 		casts       []int
@@ -92,14 +132,17 @@ func Cast(dieSurfaces, castAmount int) {
 		total += cast
 	}
 
-	if modifier != 0 {
+	switch {
+	case modifier != 0:
 		fmt.Printf("%sRolling %dd%d + %d...\n%s", ColorYellow, diceThrows, surfaces, modifier, ColorReset)
-	} else {
+	default:
 		fmt.Printf("%sRolling %dd%d...\n%s", ColorYellow, diceThrows, surfaces, ColorReset)
 	}
 
 	if castAmount > 1 {
-		fmt.Println(Color(ColorMagenta), "\tIndividual rolls:", casts, Color(ColorReset))
+		fmt.Println(Color(ColorMagenta), "\tIndividual rolls:",
+			strings.Trim(fmt.Sprint(casts), "[]"),
+			Color(ColorReset))
 	}
 
 	if modifier != 0 {