gaemstone/src/gaemstone/Flecs/Doc.cs

using System.Runtime.InteropServices;
using gaemstone.ECS;
using gaemstone.ECS.Utility;
using static flecs_hub.flecs;

namespace gaemstone.Flecs;

[BuiltIn, Module, Path("/flecs/doc")]
public partial class Doc
{
	[Tag] public struct Brief {  }
	[Tag] public struct Detail {  }
	[Tag] public struct Link {  }
	[Tag] public struct Color {  }

	[Relation, Component]
	public struct Description
	{
		internal unsafe void* Value;

		public override string? ToString()
			{ unsafe { return Marshal.PtrToStringUTF8((nint)Value); } }
		public static implicit operator string?(Description desc)
			=> desc.ToString();
	}
}

public static unsafe class DocExtensions
{
	private static Entity<TContext> Set<TContext, T>(Entity<TContext> entity, string? value)
	{
		var id = entity.World.Pair<Doc.Description, T>();

		if (value != null) {
			var str  = GlobalHeapAllocator.Instance.AllocateCString(value);
			var desc = new Doc.Description { Value = (void*)(nint)str };
			entity.Set(id, desc);
		} else {
			entity.Remove(id);
		}

		return entity;
	}

	public static string? GetDocName<TContext>(this Entity<TContext> entity, bool fallbackToEntityName = true)
		=> fallbackToEntityName || entity.Has<Doc.Description, Core.Name>()
			? ecs_doc_get_name(entity.World, entity).FlecsToString() : null;
	public static Entity<TContext> SetDocName<TContext>(this Entity<TContext> entity, string? value)
		=> Set<TContext, Core.Name>(entity, value);

	public static string? GetDocBrief<TContext>(this Entity<TContext> entity)
		=> ecs_doc_get_brief(entity.World, entity).FlecsToString()!;
	public static Entity<TContext> SetDocBrief<TContext>(this Entity<TContext> entity, string? value)
		=> Set<TContext, Doc.Brief>(entity, value);

	public static string? GetDocDetail<TContext>(this Entity<TContext> entity)
		=> ecs_doc_get_detail(entity.World, entity).FlecsToString()!;
	public static Entity<TContext> SetDocDetail<TContext>(this Entity<TContext> entity, string? value)
		=> Set<TContext, Doc.Detail>(entity, value);

	public static string? GetDocLink<TContext>(this Entity<TContext> entity)
		=> ecs_doc_get_link(entity.World, entity).FlecsToString()!;
	public static Entity<TContext> SetDocLink<TContext>(this Entity<TContext> entity, string? value)
		=> Set<TContext, Doc.Link>(entity, value);

	public static string? GetDocColor<TContext>(this Entity<TContext> entity)
		=> ecs_doc_get_color(entity.World, entity).FlecsToString()!;
	public static Entity<TContext> SetDocColor<TContext>(this Entity<TContext> entity, string? value)
		=> Set<TContext, Doc.Color>(entity, value);
}