public class Product
{
    public int ProductId { get; set; }
    public string ProductName { get; set; } = null!;
    public int ProductTypeId { get; set; }
    public string SKU { get; set; } = null!;

    public ProductType ProductType { get; set; } = null!;
    
}
public class ProductType
{
    public int ProductTypeId { get; set; }
    public string TypeName { get; set; } = null!;

    public ICollection<Product> Products { get; set; } = new List<Product>();
}
public class ProductListRequest
{
    public string ProductSearchTerm { get; set; } = "";
    public int PageNumber { get; set; } = 1;
    public int PageSize { get; set; } = 10;
}

public class ProductListResponse
{
    public List<ProductListItemResponse> InventoryItems { get; set; } = new();
    public int TotalCount { get; set; }
    public int PageNumber { get; set; }
    public int PageSize { get; set; }
}

public class ProductListItemResponse
{
    public int ProductId { get; set; }
    public string ProductName { get; set; } = null!;
    public int ProductTypeId { get; set; }
    public string SKU { get; set; } = null!;
    public string TypeName { get; set; } = null!;
}

public interface IExampleService
{
    Task<ProductListResponse> GetAllProductsAsync(ProductListRequest request, CancellationToken cancellationToken);
}

public class ExampleService : IExampleService
{
    private readonly ExampleDbContext _context;

    public ExampleService(ExampleDbContext context)
    {
        _context = context;
    }

    public async Task<ProductListResponse> GetAllProductsAsync(ProductListRequest request, CancellationToken cancellationToken)
    {
        try
        {
            // Get search from request
            var productSearchTerm = request.ProductSearchTerm;

            // Setup query
            var productList = _context.Products
            .Include(i => i.ProductType)
            .AsQueryable();

            // Apply filters
            if (!string.IsNullOrEmpty(productSearchTerm))
            {
                productList = productList.Where(i => i.ProductName.Contains(productSearchTerm));
            }

            // Get total count
            var totalCount = await productList.CountAsync(cancellationToken);

            // Apply pagination
            var results = await productList
                .OrderBy(i => i.ProductId)
                .Skip((request.PageNumber - 1) * request.PageSize)
                .Take(request.PageSize)
                .Select(i => new ProductListItemResponse
                {
                    ProductId = i.ProductId,
                    ProductName = i.ProductName,
                    ProductTypeId = i.ProductTypeId,
                    SKU = i.SKU,
                    TypeName = i.ProductType.TypeName
                })
                .ToListAsync(cancellationToken);

            return new ProductListResponse
            {
                InventoryItems = results,
                TotalCount = totalCount,
                PageNumber = request.PageNumber,
                PageSize = request.PageSize
            };
        }
        catch (Exception ex)
        {
            Console.WriteLine(ex.Message);
            return null;
        }
    }
}