using System;
using System.Collections.Generic;
using UnityEngine;

namespace NGS.MeshFusionPro;

public class CombinedMeshDataInternal : CombinedMeshData, IDisposable
{
	private CombinedMesh _root;

	private List<CombinedMeshPartInternal> _parts;

	private int _vertexCount;

	private int _trianglesCount;

	private List<Bounds> _partsBounds;

	private Bounds _boundingBox;

	public override int PartsCount => _parts.Count;

	public override int VertexCount => _vertexCount;

	protected CombinedMesh Root => _root;

	public void Initialize(CombinedMesh root)
	{
		_root = root;
		_parts = new List<CombinedMeshPartInternal>();
		OnInitialized();
	}

	public override Bounds GetBounds()
	{
		return _boundingBox;
	}

	public override Bounds GetBounds(CombinedMeshPart part)
	{
		return _partsBounds[part.Index];
	}

	public override IEnumerable<CombinedMeshPart> GetParts()
	{
		for (int i = 0; i < _parts.Count; i++)
		{
			yield return _parts[i];
		}
	}

	public void Dispose()
	{
		OnDispose();
	}

	public CombinedMeshPart[] CreateParts(IList<MeshCombineInfo> infos)
	{
		CombinedMeshPart[] array = new CombinedMeshPart[infos.Count];
		for (int i = 0; i < array.Length; i++)
		{
			MeshCombineInfo meshCombineInfo = infos[i];
			Mesh mesh = meshCombineInfo.mesh;
			Matrix4x4 transformMatrix = meshCombineInfo.transformMatrix;
			int vertexCount = _vertexCount;
			int vertexCount2 = meshCombineInfo.vertexCount;
			int trianglesCount = _trianglesCount;
			int trianglesCount2 = meshCombineInfo.trianglesCount;
			CombinedMeshPartInternal combinedMeshPartInternal = new CombinedMeshPartInternal(_root, _parts.Count, vertexCount, vertexCount2, trianglesCount, trianglesCount2);
			_parts.Add(combinedMeshPartInternal);
			array[i] = combinedMeshPartInternal;
			_vertexCount += vertexCount2;
			_trianglesCount += trianglesCount2;
			OnAddPart(combinedMeshPartInternal, mesh, transformMatrix);
		}
		OnMeshUpdated();
		return array;
	}

	public void RemoveParts(IList<CombinedMeshPart> parts)
	{
		for (int i = 0; i < parts.Count; i++)
		{
			CombinedMeshPartInternal combinedMeshPartInternal = (CombinedMeshPartInternal)parts[i];
			OnRemovePart(combinedMeshPartInternal);
			int num = _parts.IndexOf(combinedMeshPartInternal);
			int vertexCount = combinedMeshPartInternal.VertexCount;
			int trianglesCount = combinedMeshPartInternal.TrianglesCount;
			for (int j = num + 1; j < _parts.Count; j++)
			{
				CombinedMeshPartInternal combinedMeshPartInternal2 = _parts[j];
				combinedMeshPartInternal2.Offset(newVertexStart: combinedMeshPartInternal2.VertexStart - vertexCount, newTrianglesStart: combinedMeshPartInternal2.TrianglesStart - trianglesCount, newIndex: combinedMeshPartInternal2.Index - 1);
			}
			_parts.Remove(combinedMeshPartInternal);
			_vertexCount -= combinedMeshPartInternal.VertexCount;
			_trianglesCount -= combinedMeshPartInternal.TrianglesCount;
		}
		OnMeshUpdated();
	}

	protected virtual void OnInitialized()
	{
		_partsBounds = new List<Bounds>();
	}

	protected virtual void OnAddPart(CombinedMeshPart part, Mesh mesh, Matrix4x4 transform)
	{
		_partsBounds.Add(mesh.bounds.Transform(transform));
	}

	protected virtual void OnRemovePart(CombinedMeshPart part)
	{
		_partsBounds.RemoveAt(part.Index);
	}

	protected virtual void OnMeshUpdated()
	{
		_boundingBox = _root.Mesh.bounds;
	}

	protected virtual void OnDispose()
	{
	}
}