using System;
using System.Diagnostics;
using System.Linq;
using System.Net.Http;
using System.Net.Http.Json;
using System.Threading;
using System.Threading.Tasks;
using Microsoft.Extensions.Logging;
using Microsoft.VisualBasic.CompilerServices;
using Newtonsoft.Json;
using Wabbajack.Common;
using Wabbajack.Downloaders;
using Wabbajack.DTOs;
using Wabbajack.DTOs.DownloadStates;
using Wabbajack.DTOs.JsonConverters;
using Wabbajack.Networking.Http;
using Wabbajack.Networking.Http.Interfaces;
using Wabbajack.Networking.WabbajackClientApi;
using Wabbajack.Paths;
using Wabbajack.Paths.IO;
using Wabbajack.RateLimiter;

namespace Wabbajack
{
    public class LauncherUpdater
    {
        private readonly ILogger<LauncherUpdater> _logger;
        private readonly HttpClient _client;
        private readonly Client _wjclient;
        private readonly DTOSerializer _dtos;

        private readonly DownloadDispatcher _downloader;

        private static Uri GITHUB_REPO_RELEASES = new("https://api.github.com/repos/wabbajack-tools/wabbajack/releases");

        public LauncherUpdater(ILogger<LauncherUpdater> logger, HttpClient client, Client wjclient, DTOSerializer dtos,
            DownloadDispatcher downloader)
        {
            _logger = logger;
            _client = client;
            _wjclient = wjclient;
            _dtos = dtos;
            _downloader = downloader;
        }


        public static Lazy<AbsolutePath> CommonFolder = new (() =>
        {
            var entryPoint = KnownFolders.EntryPoint;

            // If we're not in a folder that looks like a version, abort
            if (!Version.TryParse(entryPoint.FileName.ToString(), out var version))
            {
                return entryPoint;
            }

            // If we're not in a folder that has Wabbajack.exe in the parent folder, abort
            if (!entryPoint.Parent.Combine(Consts.AppName).WithExtension(new Extension(".exe")).FileExists())
            {
                return entryPoint;
            }

            return entryPoint.Parent;
        });



        public async Task Run()
        {

            if (CommonFolder.Value == KnownFolders.EntryPoint)
            {
                _logger.LogInformation("Outside of standard install folder, not updating");
                return;
            }

            var version = Version.Parse(KnownFolders.EntryPoint.FileName.ToString());

            var oldVersions = CommonFolder.Value
                .EnumerateDirectories()
                .Select(f => Version.TryParse(f.FileName.ToString(), out var ver) ? (ver, f) : default)
                .Where(f => f != default)
                .Where(f => f.ver < version)
                .Select(f => f!)
                .OrderByDescending(f => f)
                .Skip(2)
                .ToArray();

            foreach (var (_, path) in oldVersions)
            {
                _logger.LogInformation("Deleting old Wabbajack version at: {Path}", path);
                path.DeleteDirectory();
            }

            var release = (await GetReleases())
                .Select(release => Version.TryParse(release.Tag, out version) ? (version, release) : default)
                .Where(r => r != default)
                .OrderByDescending(r => r.version)
                .Select(r =>
                {
                    var (version, release) = r;
                    var asset = release.Assets.FirstOrDefault(a => a.Name == "Wabbajack.exe");
                    return asset != default ? (version, release, asset) : default;
                })
                .FirstOrDefault();

            var launcherFolder = KnownFolders.EntryPoint.Parent;
            var exePath = launcherFolder.Combine("Wabbajack.exe");

            var launcherVersion = FileVersionInfo.GetVersionInfo(exePath.ToString());

            if (release != default && release.version > Version.Parse(launcherVersion.FileVersion!))
            {
                _logger.LogInformation("Updating Launcher from {OldVersion} to {NewVersion}", launcherVersion.FileVersion, release.version);
                var tempPath = launcherFolder.Combine("Wabbajack.exe.temp");

                await _downloader.Download(new Archive
                {
                    State = new Http {Url = release.asset.BrowserDownloadUrl!},
                    Name = release.asset.Name,
                    Size = release.asset.Size
                }, tempPath, CancellationToken.None);

                if (tempPath.Size() != release.asset.Size)
                {
                    _logger.LogInformation(
                        "Downloaded launcher did not match expected size: {DownloadedSize} expected {ExpectedSize}", tempPath.Size(), release.asset.Size);
                    return;
                }

                if (exePath.FileExists())
                    exePath.Delete();
                await tempPath.MoveToAsync(exePath, true, CancellationToken.None);

                _logger.LogInformation("Finished updating wabbajack");
                await _wjclient.SendMetric("updated_launcher", $"{launcherVersion.FileVersion} -> {release.version}");
            }
        }

        private async Task<Release[]> GetReleases()
        {
            _logger.LogInformation("Getting new Wabbajack version list");
            var msg = MakeMessage(GITHUB_REPO_RELEASES);
            return await _client.GetJsonFromSendAsync<Release[]>(msg, _dtos.Options);
        }

        private HttpRequestMessage MakeMessage(Uri uri)
        {
            var msg =  new HttpRequestMessage(HttpMethod.Get, uri);
            msg.AddChromeAgent();
            return msg;
        }


        class Release
        {
            [JsonProperty("tag_name")] public string Tag { get; set; } = "";

            [JsonProperty("assets")] public Asset[] Assets { get; set; } = Array.Empty<Asset>();

        }

        class Asset
        {
            [JsonProperty("browser_download_url")]
            public Uri? BrowserDownloadUrl { get; set; }

            [JsonProperty("name")] public string Name { get; set; } = "";

            [JsonProperty("size")] public long Size { get; set; } = 0;
        }
    }
}