using LiteCharms.Infrastructure.Database;

namespace LiteCharms.Features.ShoppingCarts.Commands.Handlers;

public class RemovePackageFromShoppingCartCommandHandler(IDbContextFactory<ShopDbContext> contextFactory) : IRequestHandler<RemovePackageFromShoppingCartCommand, Result>
{
    public async ValueTask<Result> Handle(RemovePackageFromShoppingCartCommand request, CancellationToken cancellationToken)
    {
        try
        {
            using var context = await contextFactory.CreateDbContextAsync(cancellationToken);

            if (!await context.ShoppingCarts.AnyAsync(c => c.Id == request.ShoppingCartId, cancellationToken))
                return Result.Fail($"Shopping cart could not be found by ID {request.ShoppingCartId}");

            if (!await context.ShoppingCartPackages.AnyAsync(p => p.Id == request.ShoppingCartPackageId, cancellationToken))
                return Result.Fail($"Shopping cart package {request.ShoppingCartPackageId} is not in the shopping cart {request.ShoppingCartId}");

            var shoppingCartPackage = await context.ShoppingCartPackages.FirstOrDefaultAsync(cp => cp.Id == request.ShoppingCartPackageId, cancellationToken);

            if (shoppingCartPackage is null)
                return Result.Ok();

            context.ShoppingCartPackages.Remove(shoppingCartPackage!);

            return await context.SaveChangesAsync(cancellationToken) > 0
                ? Result.Ok()
                : Result.Fail($"Could remove package of id {request.ShoppingCartPackageId} from shopping cart {request.ShoppingCartId}");
        }
        catch (Exception ex)
        {
            return Result.Fail(new Error(ex.Message).CausedBy(ex));
        }
    }
}