dice-roller/main.go

package main

import (
	"flag"
	"fmt"
	"math/rand"
	"os"
	"time"

	"gitlab.com/EternalWanderer/dice-roller/Coin"
	"gitlab.com/EternalWanderer/dice-roller/Colors"
	"gitlab.com/EternalWanderer/dice-roller/Dice"
)

var (
	surfaces, modifier, diceThrows, attacks int
	advantage, disadvantage, coin           bool
)

func main() {
	ParseFlags()
	rand.Seed(time.Now().Unix())

	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:
		Coin.Toss(diceThrows)

	case advantage:
		if modifier > 0 {
			fmt.Printf("%sRolling 1d20 + %d with advantage...%s\n", Colors.ColorGreen, modifier, Colors.ColorReset)
		} else {
			fmt.Printf("%sRolling 1d20 with advantage...%s\n", Colors.ColorGreen, Colors.ColorReset)
		}
		fmt.Printf("\t%s%d%s\n", Colors.ColorGreen, Dice.Advantage(Dice.SimpleCast(modifier), Dice.SimpleCast(modifier)), Colors.ColorReset)

	case disadvantage:
		if modifier != 0 {
			fmt.Printf("%sRolling 1d20 + %d with disadvantage...%s\n", Colors.ColorRed, modifier, Colors.ColorReset)
		} else {
			fmt.Printf("%sRolling 1d20 with disadvantage...%s\n", Colors.ColorRed, Colors.ColorReset)
		}
		fmt.Printf("\t%s%d%s\n", Colors.ColorRed, Dice.Disadvantage(Dice.SimpleCast(modifier), Dice.SimpleCast(modifier)), Colors.ColorReset)

	case attacks > 1:
		for i := 0; i < attacks; i++ {
			fmt.Printf("%sAttack %d:%s\n", Colors.ColorBlue, i+1, Colors.ColorReset)
			Dice.Cast(surfaces, diceThrows, modifier)
		}
	default:
		Dice.Cast(surfaces, diceThrows, modifier)
	}
}

func ParseFlags() {
	flag.IntVar(&surfaces, "surfaces", 20, "Use to specify die surfaces, does not apply to advantage and disadvantage")
	flag.IntVar(&surfaces, "s", 20, "Use to specify die surfaces, defaults to 20")

	flag.IntVar(&diceThrows, "throws", 1, "Specify amount of dice to cast")
	flag.IntVar(&diceThrows, "c", 1, "Specify amount of dice to cast")

	flag.IntVar(&modifier, "modifier", 0, "Add modifier to result of rolls")
	flag.IntVar(&modifier, "m", 0, "Add modifier to result of rolls")

	flag.IntVar(&attacks, "attacks", 1, "Roll a set rules multiple times, does not apply to advantage and disadvantage")
	flag.IntVar(&attacks, "a", 1, "Roll a set rules multiple times, does not apply to advantage and disadvantage")

	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()
}