using System.Net;
using System.Net.Http.Json;
using Prefab.Web.Client.Models.Shared;

namespace Prefab.Web.Client.Services;

public interface INavMenuService
{
    Task<Result<NavMenuModel>> Get(int depth, CancellationToken cancellationToken);   
}

public sealed class NavMenuService : INavMenuService
{
    private readonly HttpClient _httpClient;

    public NavMenuService(HttpClient httpClient)
    {
        _httpClient = httpClient ?? throw new ArgumentNullException(nameof(httpClient));
    }

    public async Task<Result<NavMenuModel>> Get(int depth, CancellationToken cancellationToken)
    {
        var normalizedDepth = Math.Clamp(depth, 1, 2);

        try
        {
            using var response = await _httpClient.GetAsync($"/bff/nav-menu/{normalizedDepth}", cancellationToken);

            var payload = await response.Content.ReadFromJsonAsync<Result<NavMenuModel>>(cancellationToken: cancellationToken);

            if (payload is not null)
            {
                return payload;
            }

            if (!response.IsSuccessStatusCode)
            {
                var statusCode = (HttpStatusCode)response.StatusCode;
                var problem = ResultProblem.Unexpected(
                    "Failed to load navigation menu.",
                    new HttpRequestException($"Navigation menu request failed with status code {(int)statusCode} ({statusCode})."),
                    statusCode);

                return Result<NavMenuModel>.Failure(problem);
            }

            var emptyProblem = ResultProblem.Unexpected(
                "Failed to load navigation menu.",
                new InvalidOperationException("Navigation menu response body was empty."),
                (HttpStatusCode)response.StatusCode);

            return Result<NavMenuModel>.Failure(emptyProblem);
        }
        catch (Exception exception)
        {
            var problem = ResultProblem.Unexpected("Failed to load navigation menu.", exception);
            return Result<NavMenuModel>.Failure(problem);
        }
    }
}