package tome_lib

import (
	"fmt"
	"math/rand"
	"time"
)

type Deck struct {
	Cards []*Card `json:"cards"`
}

func (d *Deck) String() string {
	if d == nil {
		return "||"
	}
	return fmt.Sprintf("|%v|", d.Cards)
}

func DeckFromCards(c []*Card) *Deck {
	return &Deck{
		Cards: c,
	}
}
func DeckFromCard(c *Card) *Deck {
	if c == nil {
		return &Deck{
			Cards: []*Card{},
		}
	}
	return &Deck{
		Cards: []*Card{c},
	}
}
func (d *Deck) Shuffle() {
	r := rand.New(rand.NewSource(time.Now().UnixNano()))
	for i := range d.Cards {
		j := r.Intn(i + 1)
		d.Cards[i], d.Cards[j] = d.Cards[j], d.Cards[i]
	}
}

func (d *Deck) Scry(s int) *Deck {
	var seen []*Card
	if len(d.Cards) == 0 {
		return DeckFromCard(nil)
	} else if len(d.Cards) < s {
		seen := make([]*Card, len(d.Cards))
		copy(seen, d.Cards)
		d.Reset()
	} else {
		seen = make([]*Card, s)
		scrybox := d.Cards[(len(d.Cards) - s):len(d.Cards)]
		res := copy(seen, scrybox)
		if res == 0 {
			panic("Error copy scrybox")
		}
		d.Cards = d.Cards[0 : len(d.Cards)-s]
	}
	return DeckFromCards(seen)
}

func (d *Deck) Bottom(bot *Deck) {
	d.Cards = append(bot.Cards, d.Cards...) //Should shuffle result first?
}

func (d *Deck) Size() int {
	return len(d.Cards)
}

func (d *Deck) Reset() {
	d.Cards = []*Card{}
}