lottery-cli/cmd/lottery/main.go

package main

import (
	"context"
	"fmt"
	"os"
	"runtime/debug"
	"strings"

	"charm.land/huh/v2"
	"github.com/charmbracelet/fang"
	"github.com/spf13/cobra"
	"github.com/spf13/viper"

	"github.com/onyx-and-iris/lottery-cli"
)

var version string

func versionFromBuild() string {
	if version != "" {
		return version
	}

	info, ok := debug.ReadBuildInfo()
	if !ok {
		return "(unable to read version)"
	}
	return strings.Split(info.Main.Version, "-")[0]
}

var rootCmd = &cobra.Command{
	Use:   "lottery",
	Short: "A CLI for National Lottery games.",
	PreRunE: func(cmd *cobra.Command, args []string) error {
		cmd.MarkFlagsMutuallyExclusive("count", "count-prompt")

		return nil
	},
	RunE: func(cmd *cobra.Command, args []string) error {
		kindStr := viper.GetString("kind")
		if kindStr == "" {
			form := huh.NewForm(
				huh.NewGroup(
					huh.NewSelect[string]().
						Title("Pick a lottery.").
						Options(kindPromptOptions()...).
						Value(&kindStr),
				),
			)
			err := form.Run()
			if err != nil {
				return err
			}
		}

		kind, err := lottery.ParseKind(kindStr)
		if err != nil {
			return err
		}

		l, err := lottery.New(kind)
		if err != nil {
			return err
		}

		if countPrompt := viper.GetBool("count-prompt"); countPrompt {
			var count string
			if err := huh.NewInput().
				Title("How many draws would you like to generate?").
				Value(&count).Run(); err != nil {
				return err
			}

			viper.Set("count", count)
		}

		count := viper.GetInt("count")
		includeDrawHeading := count > 1
		renders := make([]string, 0, count)
		drawTitle := "Lottery"

		for i := range count {
			l.Draw()
			title, entry := renderDrawEntry(l, i+1, includeDrawHeading)
			drawTitle = title
			renders = append(renders, entry)
		}

		if len(renders) > 0 {
			fmt.Println(renderDrawCollection(drawTitle, renders))
		}

		return nil
	},
}

func kindPromptLabel(kind lottery.Kind) string {
	switch kind {
	case lottery.KindLotto:
		return "Lotto"
	case lottery.KindEuroMillions:
		return "EuroMillions"
	case lottery.KindSetForLife:
		return "Set For Life"
	case lottery.KindThunderball:
		return "Thunderball"
	case lottery.KindPowerball:
		return "Powerball"
	default:
		return string(kind)
	}
}

func kindPromptOptions() []huh.Option[string] {
	kinds := lottery.AllKinds()
	options := make([]huh.Option[string], 0, len(kinds))
	for _, kind := range kinds {
		options = append(options, huh.NewOption(kindPromptLabel(kind), string(kind)))
	}
	return options
}

func init() {
	rootCmd.Flags().StringP("kind", "k", "", "Lottery kind to generate draws for.")
	rootCmd.Flags().IntP("count", "c", 1, "Number of draws to generate.")
	rootCmd.Flags().BoolP("count-prompt", "C", false, "Prompt for the number of draws to generate.")

	viper.SetEnvKeyReplacer(strings.NewReplacer("-", "_"))
	viper.SetEnvPrefix("LOTTERY")
	viper.AutomaticEnv()
	if err := viper.BindPFlags(rootCmd.Flags()); err != nil {
		panic(err)
	}
}

func main() {
	if err := fang.Execute(
		context.Background(),
		rootCmd,
		fang.WithVersion(versionFromBuild()),
	); err != nil {
		os.Exit(1)
	}
}