using System;
using System.Collections;
using System.Collections.Generic;
using System.Linq;
using UnityEditor;
using UnityEngine;

[CustomEditor(typeof(CombineMeshs))]
public class CombineMeshsEditor : Editor
{
    CombineMeshs inst;

    private void OnEnable()
    {
        inst = (CombineMeshs)target;
    }

    public override void OnInspectorGUI()
    {
        base.OnInspectorGUI();

        //
        if(GUILayout.Button("CombineMeshs", GUILayout.Height(50)))
        {
            if(!inst.isCombineSubmesh)
            {
                AAA();
            }
            else
            {
                AAB();
            }
        }
    }

    void AAA()
    {
        List< CombineInstance > combineInstances = new List< CombineInstance >();
        List<Material> materials = new List< Material >();
        foreach(Transform t in inst.root.GetComponent<Transform>())
        {
            if(t.gameObject.activeSelf && t.GetComponent<MeshFilter>())
            {
                CombineInstance combineInstance = new CombineInstance();

                combineInstance.mesh = t.GetComponent<MeshFilter>().sharedMesh;
                combineInstance.transform = inst.root.worldToLocalMatrix * t.localToWorldMatrix;
                combineInstances.Add(combineInstance);

                materials.AddRange(t.GetComponent<MeshRenderer>().sharedMaterials);

                t.gameObject.SetActive(false);
            }
        }

        Mesh mesh = new Mesh();
        mesh.indexFormat = UnityEngine.Rendering.IndexFormat.UInt32;
        mesh.CombineMeshes(combineInstances.ToArray(), false);

        GameObject obj = new GameObject();
        obj.transform.position = inst.root.transform.position;
        obj.transform.SetParent(inst.root.transform);
        obj.AddComponent<MeshFilter>();
        obj.AddComponent<MeshRenderer>();

        obj.GetComponent<MeshFilter>().sharedMesh = mesh;
        obj.GetComponent<MeshRenderer>().sharedMaterials = materials.ToArray();
    }

    void AAB()
    {
        List<CombineInstance> combineInstances = new List<CombineInstance>();
        List<Material> materials = new List<Material>();
        foreach (Transform t in inst.root.GetComponentsInChildren<Transform>())
        {
            if (t.gameObject.activeSelf && t.GetComponent<MeshFilter>() && t.GetComponent<MeshFilter>().sharedMesh)
            {
                CombineInstance combineInstance = new CombineInstance();

                for (int i = 0; i < t.GetComponent<MeshFilter>().sharedMesh.subMeshCount; ++i)
                {
                    combineInstance.mesh = t.GetComponent<MeshFilter>().sharedMesh;
                    combineInstance.transform = inst.root.worldToLocalMatrix * t.localToWorldMatrix;
                    combineInstance.subMeshIndex = i;
                    combineInstances.Add(combineInstance);
                }

                //
                for (int i = 0; i < t.GetComponent<MeshRenderer>().sharedMaterials.Length; ++i)
                {
                    if (!materials.Contains(t.GetComponent<MeshRenderer>().sharedMaterials[i]))
                    {
                        materials.Add(t.GetComponent<MeshRenderer>().sharedMaterials[i]);
                    }
                }

                t.gameObject.SetActive(false);
            }
        }

        Mesh mesh = new Mesh();
        mesh.indexFormat = UnityEngine.Rendering.IndexFormat.UInt32;
        mesh.CombineMeshes(combineInstances.ToArray(), true);

        GameObject obj = new GameObject();
        obj.transform.position = inst.root.transform.position;
        obj.transform.SetParent(inst.root.transform);
        obj.AddComponent<MeshFilter>();
        obj.AddComponent<MeshRenderer>();

        obj.GetComponent<MeshFilter>().sharedMesh = mesh;
        obj.GetComponent<MeshRenderer>().sharedMaterials = materials.ToArray();

        Debug.Log("Done!");
    }
}