using Newtonsoft.Json;
using Newtonsoft.Json.Converters;
using System.Globalization;
using System.Net.Http.Headers;
using System.Text.RegularExpressions;

namespace ChrisKaczor.ApplicationUpdate
{
    public partial class GitHubRelease
    {
        private const string LatestSegment = "/latest";

        private static readonly HttpClient HttpClient = new()
        {
            DefaultRequestHeaders =
                { UserAgent = { ProductInfoHeaderValue.Parse(UpdateCheck.ApplicationName.Replace(" ", "")) } }
        };

        private static GitHubRelease? FromJson(string json) =>
            JsonConvert.DeserializeObject<GitHubRelease>(json, Converter.Settings);

        private static List<GitHubRelease>? FromJsonArray(string json) =>
            JsonConvert.DeserializeObject<List<GitHubRelease>>(json, Converter.Settings);

        [JsonProperty("tag_name")] public string? TagName { get; set; }

        [JsonProperty("assets")] public List<Asset>? Assets { get; set; }

        [JsonProperty("prerelease")] public bool Prerelease { get; set; }

        public static async Task<VersionInfo?> GetLatestAsync(string baseUrl)
        {
            try
            {
                var url = baseUrl.EndsWith(LatestSegment) ? baseUrl : baseUrl + LatestSegment;

                var json = await HttpClient.GetStringAsync(url);

                var release = FromJson(json);

                var versionInfo = VersionInfo.CreateFromGitHubRelease(release);

                return versionInfo;
            }
            catch (Exception)
            {
                return null;
            }
        }

        public static async Task<VersionInfo?> GetLatestPrereleaseAsync(string baseUrl)
        {
            try
            {
                var url = baseUrl.EndsWith(LatestSegment) ? baseUrl[..^LatestSegment.Length] : baseUrl;

                var json = await HttpClient.GetStringAsync(url);

                var releases = FromJsonArray(json);

                var release = releases?.FirstOrDefault();

                if (release == null)
                    return null;

                var versionInfo = VersionInfo.CreateFromGitHubRelease(release);

                return versionInfo;
            }
            catch (Exception)
            {
                return null;
            }
        }
    }

    public class Asset
    {
        [JsonProperty("created_at")] public DateTimeOffset? CreatedAt { get; set; }

        [JsonProperty("browser_download_url")] public string? BrowserDownloadUrl { get; set; }
    }

    internal class Converter
    {
        public static readonly JsonSerializerSettings Settings = new()
        {
            MetadataPropertyHandling = MetadataPropertyHandling.Ignore,
            DateParseHandling = DateParseHandling.None,
            Converters =
            {
                new IsoDateTimeConverter { DateTimeStyles = DateTimeStyles.AssumeUniversal }
            }
        };
    }
}