using System.Reflection;
using System.Runtime.InteropServices;
using CursorLang.Core.Interop;
using Windows.ApplicationModel;

namespace CursorLang.Core.Services;

/// <summary>
/// The version of the running application.
/// </summary>
/// <remarks>
/// The same application runs from a package and from a folder, and the two keep
/// their version in different places. The answer is computed once: it cannot
/// change while the process lives.
/// </remarks>
public static class AppVersion
{
    public static Version Current { get; } = Detect();

    private static Version Detect()
    {
        if (PackageIdentityNative.IsPackaged)
        {
            try
            {
                PackageVersion version = Package.Current.Id.Version;
                return new Version(version.Major, version.Minor, version.Build, version.Revision);
            }
            catch (Exception e) when (e is COMException or InvalidOperationException)
            {
                // The package was built without a version in the manifest — the assembly version is left
            }
        }

        return Assembly.GetEntryAssembly()?.GetName().Version ?? new Version(0, 0, 0, 0);
    }
}