package game

import "fmt"

// Suit is the trade-in symbol printed on pet cards. Three pets of the same
// suit can be traded for a pick of the next tier's deck.
type Suit string

const (
	SuitSun  Suit = "sun"
	SuitMoon Suit = "moon"
	SuitStar Suit = "star"
	SuitLeaf Suit = "leaf"
)

var suits = []Suit{SuitSun, SuitMoon, SuitStar, SuitLeaf}

// CardKind distinguishes pets from foods.
type CardKind string

const (
	KindPet  CardKind = "pet"
	KindFood CardKind = "food"
)

// Food identifiers. Only apples exist for now; more foods come later.
const FoodApple = "apple"

// Card is a single physical card instance. IDs are unique per game.
type Card struct {
	ID    string   `json:"id"`
	Kind  CardKind `json:"kind"`
	Name  string   `json:"name"`
	Tier  int      `json:"tier"`
	Power int      `json:"power,omitempty"`
	Suit  Suit     `json:"suit,omitempty"`
	// Effect is display text for the pet's ability. Effects are not yet
	// implemented mechanically; the field keeps card data forward-compatible.
	Effect string `json:"effect,omitempty"`
	Food   string `json:"food,omitempty"`
}

func (c Card) IsPet() bool  { return c.Kind == KindPet }
func (c Card) IsFood() bool { return c.Kind == KindFood }

// petTemplate is the printed definition of a pet; each template appears as
// multiple card copies in its tier's shop deck.
type petTemplate struct {
	Name  string
	Power int
}

const copiesPerPet = 2

// petTiers defines the shop decks. Index 0 is tier 1 (round 1) through
// index 5 for tier 6 (round 6). Suits are assigned round-robin per tier so
// every tier contains every suit.
var petTiers = [MaxRounds][]petTemplate{
	{ // Tier 1
		{"Ant", 1}, {"Cricket", 1}, {"Fish", 2}, {"Horse", 1},
		{"Beaver", 2}, {"Otter", 1}, {"Pig", 3}, {"Mosquito", 2},
	},
	{ // Tier 2
		{"Crab", 3}, {"Swan", 2}, {"Hedgehog", 3}, {"Peacock", 4},
		{"Flamingo", 3}, {"Rat", 2}, {"Shrimp", 2}, {"Spider", 3},
	},
	{ // Tier 3
		{"Dog", 4}, {"Badger", 4}, {"Camel", 3}, {"Giraffe", 3},
		{"Kangaroo", 4}, {"Ox", 5}, {"Rabbit", 3}, {"Sheep", 4},
	},
	{ // Tier 4
		{"Skunk", 5}, {"Hippo", 6}, {"Bison", 6}, {"Deer", 4},
		{"Squirrel", 4}, {"Whale", 5}, {"Worm", 4}, {"Penguin", 5},
	},
	{ // Tier 5
		{"Scorpion", 5}, {"Rhino", 7}, {"Monkey", 6}, {"Cow", 6},
		{"Seal", 6}, {"Shark", 7}, {"Turkey", 5}, {"Crocodile", 8},
	},
	{ // Tier 6
		{"Leopard", 8}, {"Boar", 9}, {"Fly", 7}, {"Gorilla", 9},
		{"Mammoth", 10}, {"Snake", 8}, {"Tiger", 9}, {"Dragon", 10},
	},
}

// newCardID mints a unique card ID within the game.
func (g *Game) newCardID() string {
	g.NextCardID++
	return fmt.Sprintf("c%d", g.NextCardID)
}

// buildShopDecks creates all six tier decks (unshuffled).
func (g *Game) buildShopDecks() {
	g.ShopDecks = make([][]Card, MaxRounds)
	for tierIdx, templates := range petTiers {
		deck := make([]Card, 0, len(templates)*copiesPerPet)
		for i, t := range templates {
			for range copiesPerPet {
				deck = append(deck, Card{
					ID:    g.newCardID(),
					Kind:  KindPet,
					Name:  t.Name,
					Tier:  tierIdx + 1,
					Power: t.Power,
					Suit:  suits[i%len(suits)],
				})
			}
		}
		g.ShopDecks[tierIdx] = deck
	}
}

// newApple mints an apple food card (from discarding, etc.).
func (g *Game) newApple() Card {
	return Card{
		ID:   g.newCardID(),
		Kind: KindFood,
		Name: "Apple",
		Food: FoodApple,
	}
}