#region ================== Namespaces

using CodeImp.DoomBuilder.Config;
using CodeImp.DoomBuilder.Map;
using CodeImp.DoomBuilder.Types;
using System.Collections.Generic;

#endregion

namespace CodeImp.DoomBuilder.BuilderModes
{
	public abstract class BaseActionTextures
	{
		#region ================== Variables

		private List<int> tags;

		#endregion

		#region ================== Constructor / Destructor

		public BaseActionTextures()
		{
			tags = FindTags();
		}

		#endregion

		#region ================== Methods

		// Determine if the sidedef's sector tag is for an inspected action and the sidedef will require a texture.
		public bool RequiresTexture(Sidedef side, int tag)
		{
			return tags.Contains(tag) &&
				side.Other != null &&
				side.Other.Sector != side.Sector &&
				!side.Other.Sector.Tags.Contains(tag) &&
				HasAdjustedSector(side);
		}

		// Gather all sector tags for the linedef actions being inspected.
		private List<int> FindTags()
		{
			List<int> actions = FindActions();
			List<int> tags = new List<int>();
			int tag;

			foreach (Linedef ld in General.Map.Map.Linedefs)
			{
				if (ld.Action > 0 && actions.Contains(ld.Action))
				{
					if (General.Map.HEXEN || General.Map.UDMF)
						tag = FindArgumentsSectorTag(ld.Action, ld.Args);
					else
						tag = ld.Tag;

					if (tag > 0)
						tags.Add(tag);
				}
			}

			if (General.Map.HEXEN || General.Map.UDMF)
			{
				foreach (Thing t in General.Map.Map.Things)
				{
					if (t.Action > 0 && actions.Contains(t.Action))
					{
						tag = FindArgumentsSectorTag(t.Action, t.Args);

						if (tag > 0)
							tags.Add(tag);
					}
				}
			}

			return tags;
		}

		// Get the sector tag from linedef/things action arguments.
		private int FindArgumentsSectorTag(int action, int[] args)
		{
			if (General.Map.Config.GetLinedefActionInfo(action).Args[0].Type == (int)UniversalType.SectorTag)
				return args[0];

			return 0;
		}

		// Gather the linedef specials from the configuration that this will inspect.
		private List<int> FindActions()
		{
			List<int> actions = new List<int>();

			foreach (LinedefActionInfo info in General.Map.Config.LinedefActions.Values)
				if (InspectsAction(info))
					actions.Add(info.Index);

			return actions;
		}

		// Determine if tagged sectors for the given action will have its textures analyzed.
		protected abstract bool InspectsAction(LinedefActionInfo info);

		// Determine whether an upper or lower texture is required after the sector tag is activated.
		protected abstract bool HasAdjustedSector(Sidedef side);

		#endregion
	}
}