Class BasketController

API/Controllers/BasketController.cs:12–128

namespace API.Controllers;

public class BasketController(StoreContext context,
    DiscountService couponService, PaymentsService paymentsService) : BaseApiController
{
    [HttpGet]
    public async Task<ActionResult<BasketDto>> GetBasket()
    {
        var basket = await RetrieveBasket();

        if (basket == null) return NoContent();

        return basket.ToDto();
    }

    [HttpPost]
    public async Task<ActionResult<BasketDto>> AddItemToBasket(int productId, int quantity)
    {
        var basket = await RetrieveBasket();

        basket ??= CreateBasket();

        var product = await context.Products.FindAsync(productId);

        if (product == null) return BadRequest("Problem adding item to basket");

        basket.AddItem(product, quantity);

        var result = await context.SaveChangesAsync() > 0;

        if (result) return CreatedAtAction(nameof(GetBasket), basket.ToDto());

        return BadRequest("Problem updating basket");
    }

    [HttpDelete]
    public async Task<ActionResult> RemoveBasketItem(int productId, int quantity)
    {
        var basket = await RetrieveBasket();

        if (basket == null) return BadRequest("Unable to retrieve basket");

        basket.RemoveItem(productId, quantity);

        var result = await context.SaveChangesAsync() > 0;

        if (result) return Ok();

        return BadRequest("Problem updating basket");
    }

    [HttpPost("{code}")]
    public async Task<ActionResult<BasketDto>> AddCouponCode(string code)
    {
        // get the basket
        var basket = await RetrieveBasket();
        if (basket == null || string.IsNullOrEmpty(basket.ClientSecret)) return BadRequest("Unable to apply voucher");

        // get the coupon
        var coupon = await couponService.GetCouponFromPromoCode(code);