package main

import (
	"fmt"
	"io/ioutil"
	"math/rand"
	"os"
	"strings"
	"time"
)

type deck []string

func (d deck) print() {
	for i, card := range d {
		fmt.Println(i, card)
	}
}

func (d deck) toString(seperator string) string {
	return strings.Join(d, "\n")
}

func (d deck) save(filename string) error {
	return ioutil.WriteFile(filename, []byte(d.toString("\n")), 0644)
}

func (d deck) shuffle() deck {
	rand.Seed(time.Now().UnixNano())
	for i, _ := range d {
		indexToSwap := rand.Intn(len(d) - 1)
		d[i], d[indexToSwap] = d[indexToSwap], d[i]
	}
	return d
}

func newDeck() deck {
	cards := deck{}
	cardSuits := []string{"Spades", "Diamonds", "Hearts", "Clubs"}
	cardValues := []string{"Ace", "Two", "Three", "Four"}
	for _, suite := range cardSuits {
		for _, value := range cardValues {
			cards = append(cards, value+" of "+suite)
		}
	}
	return cards
}

func deal(d deck, handsize int) (deck, deck) {
	return d[:handsize], d[handsize:]
}

func fromString(input []byte, seperator string) deck {
	return deck(strings.Split(string(input), seperator))
}

func load(filename string) deck {
	bytes, err := ioutil.ReadFile(filename)
	if err != nil {
		fmt.Println("Error: ", err)
		os.Exit(1)
	}
	return fromString(bytes, "\n")
}