using MatterHackers.Agg.PlatformAbstract;
using System.IO;

namespace MatterHackers.MatterControl
{
	public class VersionInfo
	{
		private static VersionInfoContainer globalInstance;

		public static VersionInfoContainer Instance
		{
			get
			{
				if (globalInstance == null)
				{
					VersionInfoHandler versionInfoHandler = new VersionInfoHandler();
					globalInstance = versionInfoHandler.ImportVersionInfoFromJson();
				}
				return globalInstance;
			}
		}
	}

	public class VersionInfoContainer
	{
		public VersionInfoContainer()
		{
		}

		public string ReleaseVersion { get; set; }

		public string BuildVersion { get; set; }

		public string BuildToken { get; set; }

		public string ProjectToken { get; set; }
	}

	internal class VersionInfoHandler
	{
		public VersionInfoHandler()
		{
		}

		public VersionInfoContainer ImportVersionInfoFromJson(string loadedFileName = null)
		{
			// TODO: Review all cases below. What happens if we return a default instance of VersionInfoContainer or worse yet, null. It seems likely we end up with a null
			// reference error when someone attempts to use VersionInfo.Instance and it's invalide. Consider removing the error handing below and throwing an error when
			// an error condition is found rather than masking it until the user goes to a section that relies on the instance - thus moving detection of the problem to
			// an earlier stage and expanding the number of cases where it would be noticed.
			string content = loadedFileName == null ?
					StaticData.Instance.ReadAllText(Path.Combine("BuildInfo.txt")) :
					System.IO.File.Exists(loadedFileName) ? System.IO.File.ReadAllText(loadedFileName) : "";

			if (!string.IsNullOrWhiteSpace(content))
			{
				VersionInfoContainer versionInfo = (VersionInfoContainer)Newtonsoft.Json.JsonConvert.DeserializeObject(content, typeof(VersionInfoContainer));
				if (versionInfo == null)
				{
					return new VersionInfoContainer();
				}
				return versionInfo;
			}
			else
			{
				return null;
			}
		}
	}
}