package model

import (
	"errors"
	"strconv"
	"strings"
)

type ProductID int

var productID ProductID = 1

type Product struct {
	ID       ProductID
	Name     string
	Category string
	Price    float64
	Quantity int
}

type ProductInput struct {
	Name     string
	Category string
	Price    float64
	Quantity int
}

type Inventory struct {
	products map[ProductID]Product
}

func NewInventory() *Inventory {
	return &Inventory{products: make(map[ProductID]Product)}
}

func (e *Inventory) AddProduct(i *ProductInput) *Product {
	product := Product{
		ID:       productID,
		Name:     i.Name,
		Category: i.Category,
		Price:    i.Price,
		Quantity: i.Quantity,
	}

	e.products[productID] = product

	productID += 1

	return &product
}

func (e *Inventory) FetchProducts() map[ProductID]Product {
	return e.products
}

func (e *Inventory) UpdateProduct(id ProductID, field, value string) (*Product, error) {
	product, ok := e.products[id]

	if !ok {
		return nil, errors.New("Produto não encontrado")
	}

	switch strings.ToLower(field) {
	case "nome", "name":
		product.Name = value
	case "categoria", "category":
		product.Category = value
	case "preco", "preço", "price":
		price, err := strconv.ParseFloat(value, 64)
		if err != nil {
			return nil, errors.New("Preço inválido")
		}
		product.Price = price
	case "quantidade", "quantity":
		quantity, err := strconv.Atoi(value)
		if err != nil {
			return nil, errors.New("Quantidade inválida")
		}
		product.Quantity = quantity
	default:
		return nil, errors.New("Campo inválido")
	}

	e.products[id] = product

	return &product, nil
}

func (e *Inventory) DeleteProduct() {}