using System;
using System.Diagnostics;
using System.Net.Http;
using System.Reflection;
using System.Text.Json;
using System.Threading.Tasks;

namespace DellMonitorControl;

public class UpdateChecker
{
    private const string ReleasesApiUrl = "https://git.marketally.com/api/v1/repos/misc/ControlMyMonitorManagement/releases/latest";
    private static readonly HttpClient _httpClient = new() { Timeout = TimeSpan.FromSeconds(10) };

    public static Version CurrentVersion => Assembly.GetExecutingAssembly().GetName().Version ?? new Version(1, 0, 0);

    public static async Task<UpdateInfo?> CheckForUpdateAsync()
    {
        try
        {
            DebugLogger.Log($"Checking for updates... Current version: {CurrentVersion}");

            var response = await _httpClient.GetStringAsync(ReleasesApiUrl);
            var release = JsonSerializer.Deserialize<GiteaRelease>(response);

            if (release == null || string.IsNullOrEmpty(release.tag_name))
            {
                DebugLogger.Log("No release info found");
                return null;
            }

            var latestVersionStr = release.tag_name.TrimStart('v', 'V');
            if (!Version.TryParse(latestVersionStr, out var latestVersion))
            {
                DebugLogger.Log($"Could not parse version: {release.tag_name}");
                return null;
            }

            DebugLogger.Log($"Latest version: {latestVersion}");

            if (latestVersion > CurrentVersion)
            {
                // Find the installer asset
                string? downloadUrl = null;
                if (release.assets != null)
                {
                    foreach (var asset in release.assets)
                    {
                        if (asset.name?.EndsWith(".exe", StringComparison.OrdinalIgnoreCase) == true)
                        {
                            downloadUrl = asset.browser_download_url;
                            break;
                        }
                    }
                }

                // Fallback to release page if no direct download
                downloadUrl ??= release.html_url;

                DebugLogger.Log($"Update available: {latestVersion}, URL: {downloadUrl}");

                return new UpdateInfo
                {
                    CurrentVersion = CurrentVersion,
                    LatestVersion = latestVersion,
                    DownloadUrl = downloadUrl ?? "",
                    ReleaseNotes = release.body ?? ""
                };
            }

            DebugLogger.Log("No update available");
            return null;
        }
        catch (Exception ex)
        {
            DebugLogger.LogError("Update check failed", ex);
            return null;
        }
    }

    public static void OpenDownloadPage(string url)
    {
        try
        {
            Process.Start(new ProcessStartInfo
            {
                FileName = url,
                UseShellExecute = true
            });
        }
        catch (Exception ex)
        {
            DebugLogger.LogError("Failed to open download page", ex);
        }
    }
}

public class UpdateInfo
{
    public Version CurrentVersion { get; set; } = new(1, 0, 0);
    public Version LatestVersion { get; set; } = new(1, 0, 0);
    public string DownloadUrl { get; set; } = "";
    public string ReleaseNotes { get; set; } = "";
}

public class GiteaRelease
{
    public string? tag_name { get; set; }
    public string? name { get; set; }
    public string? body { get; set; }
    public string? html_url { get; set; }
    public GiteaAsset[]? assets { get; set; }
}

public class GiteaAsset
{
    public string? name { get; set; }
    public string? browser_download_url { get; set; }
}