/*
Copyright © 2023 NAME HERE <EMAIL ADDRESS>
*/
package cmd

import (
	"fmt"
	"strconv"
	"strings"

	"github.com/spf13/cobra"
)

// tempCmd represents the temp command
var (
	from           string
	to             string
	five_over_nine = float64(5) / float64(9)
	nine_over_five = float64(9) / float64(5)
	kconst         = 273.15
	rconst         = 459.67
	tempCmd        = &cobra.Command{
		Use:   "temp",
		Short: "A brief description of your command",
		Long: `A longer description that spans multiple lines and likely contains examples
and usage of using your command. For example:

Cobra is a CLI library for Go that empowers applications.
This application is a tool to generate the needed files
to quickly create a Cobra application.`,
		Args: cobra.MatchAll(cobra.ExactArgs(1)),
		RunE: func(cmd *cobra.Command, args []string) error {
			err := cmd.ParseFlags(args)
			if err != nil {
				return err
			}

			in, err := strconv.ParseFloat(args[0], 64)
			if err != nil {
				return err
			}
			var out float64
			switch strings.ToLower(cmd.Flag("from").Value.String()) {
			case "f", "farenheit":
				switch strings.ToLower(cmd.Flag("to").Value.String()) {
				case "f", "farenheit":
					out = in
				case "c", "celsius":
					out = ((in - 32) * five_over_nine)
				case "k", "kelvin":
					out = ((in-32)*five_over_nine + kconst)
				case "r", "rankine":
					out = in + rconst
				}
			case "c", "celsius":
				switch strings.ToLower(cmd.Flag("to").Value.String()) {
				case "f", "farenheit":
					out = in*nine_over_five + 32
				case "c", "celsius":
					out = in
				case "k", "kelvin":
					out = in + kconst
				case "r", "rankine":
					out = in*nine_over_five + rconst + 32
				}
			case "k", "kelvin":
				switch strings.ToLower(cmd.Flag("to").Value.String()) {
				case "f", "farenheit":
					out = (in-kconst)*nine_over_five + 32
				case "c", "celsius":
					out = in - kconst
				case "k", "kelvin":
					out = in
				case "r", "rankine":
					out = in * nine_over_five
				}
			case "r", "rankine":
				switch strings.ToLower(cmd.Flag("to").Value.String()) {
				case "f", "farenheit":
					out = in - rconst
				case "c", "celsius":
					out = (in - (rconst + 32)) * nine_over_five
				case "k", "kelvin":
					out = in * five_over_nine
				case "r", "rankine":
					out = in
				}
			}
			fmt.Println(strconv.FormatFloat(out, 'f', 2, 64))
			return nil
		},
	}
)

func init() {
	rootCmd.AddCommand(tempCmd)
	tempCmd.PersistentFlags().StringVarP(&from, "from", "f", "c", "unit system to convert from, (farenheit, celsius, kelvin)")
	tempCmd.PersistentFlags().StringVarP(&to, "to", "t", "f", "unit system to convert to, (farenheit, celsius, kelvin)")

	// Here you will define your flags and configuration settings.

	// Cobra supports Persistent Flags which will work for this command
	// and all subcommands, e.g.:
	// tempCmd.PersistentFlags().String("foo", "", "A help for foo")

	// Cobra supports local flags which will only run when this command
	// is called directly, e.g.:
	// tempCmd.Flags().BoolP("toggle", "t", false, "Help message for toggle")
}