package bookstore_test

import (
	"bookstore"
	"testing"
	"sort"

	"github.com/google/go-cmp/cmp"
	"github.com/google/go-cmp/cmp/cmpopts"
)

func TestBuy(t *testing.T) {
	t.Parallel()
	b := bookstore.Book{
		Title: "Lol",
		Author: "KEK",
		Copies: 2,
	}
	want := 1
	result,err := bookstore.Buy(b)
	if err != nil {
		t.Fatal(err)
	}
	got := result.Copies
	if want != got {
		t.Errorf("Want %d but got %d", want,got)
	}
}

func TestBuyOutOfStock(t *testing.T) {
	t.Parallel()
	b := bookstore.Book{
		Title: "Lol",
		Author: "KEK",
		Copies: 0,
	}
	_,err := bookstore.Buy(b)
	if err == nil {
		t.Error("Book is out of stock")
	}
}

func TestGetAllBooks(t *testing.T) {
	t.Parallel()
	catalog := bookstore.Catalog{
		1: {ID: 1, Title: "For the Love of Go"},
		2: {ID: 2, Title: "The Power of Go: Tools"},
	}
	want := []bookstore.Book{
		{ID: 1, Title: "For the Love of Go"},
		{ID: 2, Title: "The Power of Go: Tools"},
	}
	got := catalog.GetAllBooks()
	sort.Slice(got, func(i, j int) bool {
		return got[i].ID < got[j].ID
	})
	if !cmp.Equal(want, got,cmpopts.IgnoreUnexported(bookstore.Book{})) {
		t.Error(cmp.Diff(want, got,))
	}
}
func TestGetBook(t *testing.T) {
	t.Parallel()
	catalog := bookstore.Catalog{
		1: {ID: 1, Title: "For the Love of Go"},
		2: {ID: 2, Title: "The Power of Go: Tools"},
	}
    // want := bookstore.Book{ID: 2, Title: "The Power of Go: Tools"}
	_, err := catalog.GetBook(2)
	if err != nil {
        t.Fatal("want error for non-existent ID, got nil")
    } 
}
func TestNetPriceCents(t *testing.T) {
	t.Parallel()
	b := bookstore.Book {
		Title: "For the love of Go",
		PriceCents: 4000,
		DiscountPercents: 25,
	}
	want := 3000
	got := b.NetPriceCents()
	if want != got {
		t.Errorf("want %d, got %d",want,got)
	}
}
func TestSetPriceCents(t *testing.T) {
    t.Parallel()
    b := bookstore.Book{
        Title: "For the Love of Go",
        PriceCents: 4000,
    }
    want := 3000
    err := b.SetPriceCents(want)
    if err != nil {
        t.Fatal(err)
    }
    got := b.PriceCents
	if want != got {
    	t.Errorf("want updated price %d, got %d", want, got)
    }
}
func TestSetCategory(t *testing.T) {
	t.Parallel()
	b := bookstore.Book{
		Title: "For the Love of Go",
	}
	cats := []bookstore.Category {
		bookstore.CategoryAutobiography,
        bookstore.CategoryLargePrintRomance,
        bookstore.CategoryParticlePhysics,
	}
	for _, cat := range cats {
	err := b.SetCategory(cat)
	if err != nil {
		t.Fatal(err)
		}
	got := b.Category()
	if cat != got {
		t.Errorf("want category %q, got %q", cat, got)
		}
	}
}


func TestSetCategoryInvalid(t *testing.T) {
	t.Parallel()
	b := bookstore.Book{
		Title: "For the Love of Go",
	}
	err := b.SetCategory(999)
	if err == nil {
		t.Fatal("want error for invalid category, got nil")
	}
}