using AS1024.GeoFeed.Core.Interfaces;
using AS1024.GeoFeed.Models;
using System.Text.Json;
using System.Net.Http.Headers;
using System.Net.Sockets;
using System.Web;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.Logging;

namespace AS1024.GeoFeed.Core.GeoFeedProviders
{
    public abstract class NetBoxGeoFeedProviderBase : IGeoFeedProvider
    {
        protected readonly IConfiguration configuration;
        protected readonly ILogger<NetBoxGeoFeedProvider> logger;
        protected readonly IList<AddressFamily> addressFamilies = new List<AddressFamily>()
        {
            AddressFamily.InterNetwork,
            AddressFamily.InterNetworkV6
        };
        protected readonly IHttpClientFactory httpClientFactory;

        string IGeoFeedProvider.GeoFeedProviderName => "netbox";

        public NetBoxGeoFeedProviderBase(IConfiguration configuration,
                              ILogger<NetBoxGeoFeedProvider> logger,
                              IHttpClientFactory httpClientFactory)
        {
            this.configuration = configuration;
            this.logger = logger;
            this.httpClientFactory = httpClientFactory;
        }

        public async Task<List<IPGeoFeed>> GetGeoFeedDataAsync()
        {
            List<IPGeoFeed> geoFeed = [];
            using HttpClient client = httpClientFactory.CreateClient();
            client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Token", configuration["APIKey"]);
            client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));

            foreach (AddressFamily family in addressFamilies)
            {
                Uri uri = BuildNetBoxURI(family);
                NetboxData? jsonData = null;

                while (true)
                {
                    logger.LogDebug($"Making request to {uri}...");

                    using HttpResponseMessage result = await client.GetAsync(uri);
                    if (!result.IsSuccessStatusCode)
                    {
                        break;
                    }
                    string stringResult = await result.Content.ReadAsStringAsync();
                    jsonData = DeserializeJsonData(stringResult);

                    if (jsonData?.Results == null || jsonData.Results.Count == 0)
                    {
                        break;
                    }

                    foreach (Result data in jsonData.Results)
                    {
                        try
                        {
                            geoFeed.Add(new IPGeoFeed
                            {
                                Prefix = data.Prefix,
                                GeolocCity = data.CustomFields.GeolocCity,
                                GeolocRegion = data.CustomFields.GeolocRegion,
                                GeolocCountry = data.CustomFields.GeolocCountry,
                                GeolocHasLocation = data.CustomFields.GeolocHasLocation,
                                GeolocPostalCode = data.CustomFields.GeolocPostalCode
                            });
                        }
                        catch (Exception ex)
                        {
                            logger.LogError(ex.ToString());
                        }
                    }

                    if (!string.IsNullOrEmpty(jsonData.Next))
                    {
                        uri = new Uri(jsonData.Next);
                        continue;
                    }

                    break;
                }
            }

            return geoFeed;
        }

        protected virtual NetboxData? DeserializeJsonData(string stringResult)
        {
            return JsonSerializer.Deserialize<NetboxData>(stringResult, new JsonSerializerOptions
            {
                PropertyNamingPolicy = JsonNamingPolicy.SnakeCaseLower
            });
        }

        protected Uri BuildNetBoxURI(AddressFamily family)
        {
            System.Collections.Specialized.NameValueCollection queryParameters = HttpUtility.ParseQueryString(string.Empty);
            queryParameters["cf_geoloc_has_location"] = "true";
            queryParameters["limit"] = "50";

            switch (family)
            {
                case AddressFamily.InterNetwork:
                    queryParameters["mask_length__lte"] = "24";
                    queryParameters["family"] = "4";
                    break;

                case AddressFamily.InterNetworkV6:
                    queryParameters["mask_length__lte"] = "48";
                    queryParameters["family"] = "6";
                    break;
            }

            UriBuilder endUrl = new UriBuilder
            {
                Path = "api/ipam/prefixes/",
                Query = queryParameters.ToString(),
                Host = configuration["NetBoxHost"],
                Scheme = "https"
            };

            return endUrl.Uri;
        }
    }
}