package main

import (
	"flag"
	"fmt"
	"strings"
)

func main() {
	var all bool

	flag.BoolVar(&all, "all", false, "reveal the code words of all the letters in the English alphabet.")
	flag.Parse()

	if all {
		fmt.Print(phoneticLetters(fullAlphabet()))
	} else {
		fmt.Print(phoneticLetters(flag.Args()...))
	}
}

// phoneticLetters returns a string of all the code words for the given set of letters.
func phoneticLetters(input... string) string {
	var characters string

	for i := range input {
		characters = characters + strings.ToLower(input[i])
	}

	b := strings.Builder{}

	for _, r := range characters {
		switch r {
		case 'a':
			b.WriteString("A - Alpha\n")
		case 'b':
			b.WriteString("B - Bravo\n")
		case 'c':
			b.WriteString("C - Charlie\n")
		case 'd':
			b.WriteString("D - Delta\n")
		case 'e':
			b.WriteString("E - Echo\n")
		case 'f':
			b.WriteString("F - Foxtrot\n")
		case 'g':
			b.WriteString("G - Golf\n")
		case 'h':
			b.WriteString("H - Hotel\n")
		case 'i':
			b.WriteString("I - India\n")
		case 'j':
			b.WriteString("J - Juliet\n")
		case 'k':
			b.WriteString("K - Kilo\n")
		case 'l':
			b.WriteString("L - Lima\n")
		case 'm':
			b.WriteString("M - Mike\n")
		case 'n':
			b.WriteString("N - November\n")
		case 'o':
			b.WriteString("O - Oscar\n")
		case 'p':
			b.WriteString("P - Papa\n")
		case 'q':
			b.WriteString("Q - Quebec\n")
		case 'r':
			b.WriteString("R - Romeo\n")
		case 's':
			b.WriteString("S - Sierra\n")
		case 't':
			b.WriteString("T - Tango\n")
		case 'u':
			b.WriteString("U - Uniform\n")
		case 'v':
			b.WriteString("V - Victor\n")
		case 'w':
			b.WriteString("W - Whiskey\n")
		case 'x':
			b.WriteString("X - Xray\n")
		case 'y':
			b.WriteString("Y - Yankee\n")
		case 'z':
			b.WriteString("Z - Zulu\n")
		}
	}

	return b.String()
}

// fullAlphabet returns a string of all the letters in the alphabet.
func fullAlphabet() string {
	return "a b c d e f g h i j k l m n o p q r s t u v w x y z"
}