using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEditor;
using UnityEditor.PackageManager.UI;
using SourceFormatParser.BSP;
using static SourceFormatParser.BSP.SourceBSPStructs;
using System.Linq;
using Codice.Client.BaseCommands;
using System;
using System.IO;
using uSrcTools;
using Unity.VisualScripting.Antlr3.Runtime.Tree;

public class ModelImporter : EditorWindow
{
    [MenuItem("CustomTools/ModelImporter")]

    public static void ShowWindow()
    {
        EditorWindow.GetWindow(typeof(ModelImporter));
    }

    private float _worldScale = 0.0254f;


    static Vector3 ToUnityVector(SourceFormatParser.Common.SourceVector v)
    {
        return new Vector3(v.x, v.z, v.y);
    }

    static List<short> GetFaceVertexIds(SourceBSP bsp, dface_t face)
    {
        List<short> faceVertexIds = new List<short>();

        for (int e = 0; e < face.numedges; ++e) {
            var edgeId = bsp.SurfEdge[e + face.firstedge];

            bool flipped = false;
            if (edgeId < 0) {
                edgeId = -edgeId;
                flipped = true;
            }

            var edge = bsp.Edges[edgeId];

            short a;
            short b;
            if (flipped) {
                a = edge.v.y;
                b = edge.v.x;
            } else {
                a = edge.v.x;
                b = edge.v.y;
            }

            if (e == 0) {
                faceVertexIds.Add(a);
                faceVertexIds.Add(b);
            } else {
                if (a != faceVertexIds[faceVertexIds.Count - 1]) {
                    Debug.LogError("Unexpected vertex ID");
                } else {
                    if (e < face.numedges - 1) {
                        faceVertexIds.Add(b);
                    }
                }
            }
        }

        return faceVertexIds;
    }


    GameObject CreateGameObject(string name, Transform parent = null)
    {
        GameObject g = new GameObject(name);
        var mf = g.AddComponent<MeshFilter>();
        mf.sharedMesh = new Mesh();
        g.AddComponent<MeshRenderer>();

        if(parent != null) {
            g.transform.parent = parent;
        }

        g.transform.localPosition = Vector3.zero;
        g.transform.localRotation = Quaternion.identity;
        g.transform.localScale = Vector3.one;

        return g;
    }

    GameObject CreateMeshGameObject(string name, Transform parent = null)
    {
        var result = CreateGameObject(name, parent);

        var mf = result.AddComponent<MeshFilter>();
        mf.sharedMesh = new Mesh();
        result.AddComponent<MeshRenderer>();

        return result;
    }


    struct surface {
        public int index;
        public int texFlags;
        public int texID;
        public short dispinfo;

        public Vector3[] points;
        public Vector2[] uv;
        public Vector2[] uv2;
        public Color32[] cols;
        public int[] triangles;

        public int lightMapW;
        public int lightMapH;

        public Vector2 lightmapScale;
        public Vector2 lightmapOffset;
    }


    static surface BuildDispFace(SourceBSP bsp, int faceIndex)
    {
        var curFace = bsp.Faces[faceIndex];
        var dispinfoId = curFace.dispinfo;

        Vector3[] vertices = new Vector3[4];
        List<Vector3> disp_verts = new List<Vector3>();
        List<Vector2> UVs = new List<Vector2>();
        List<Color32> cols = new List<Color32>();
        List<int> indices = new List<int>();

        var curTexInfo = bsp.Texinfo[curFace.texinfo];
        var curTexData = bsp.Texdata[curTexInfo.texdata];

        int fEdge = curFace.firstedge;

        for (int i = 0; i < curFace.numedges; i++) {
            var sourceVector = (bsp.SurfEdge[fEdge + i] > 0 ?
            bsp.Vertexes[bsp.Edges[Mathf.Abs(bsp.SurfEdge[fEdge + i])].v.x] :
            bsp.Vertexes[bsp.Edges[Mathf.Abs(bsp.SurfEdge[fEdge + i])].v.y]);
            vertices[i] = ToUnityVector(sourceVector);
        }

        var curDisp = bsp.DispInfo[dispinfoId];
        Vector3 startPos = ToUnityVector(curDisp.startPosition);

        float dist;
        float minDist = 0.1f;
        int minIndex = 0;

        for (int i = 0; i < 4; i++) {
            dist = Vector3.Distance(startPos, vertices[i]);

            if (dist < minDist) {
                minDist = dist;
                minIndex = i;
            }
        }

        Vector3 temp;

        for (int i = 0; i < minIndex; i++) {
            temp = vertices[0];
            vertices[0] = vertices[1];
            vertices[1] = vertices[2];
            vertices[2] = vertices[3];
            vertices[3] = temp;
        }

        Vector3 leftEdge = vertices[1] - vertices[0];
        Vector3 rightEdge = vertices[2] - vertices[3];

        int numEdgeVertices = (1 << curDisp.power) + 1;

        float subdivideScale = 1.0f / (float)(numEdgeVertices - 1);

        Vector3 leftEdgeStep = leftEdge * subdivideScale;
        Vector3 rightEdgeStep = rightEdge * subdivideScale;

        int firstVertex = 0;

        Vector3 leftEnd;
        Vector3 rightEnd;
        Vector3 leftRightSeg;
        Vector3 leftRightStep;

        int dispVertIndex;
        CDispVert dispVert;

        Vector3 flatVertex;
        Vector3 dispVertex;

        float scaleU = (float)1f / curTexData.width;
        float scaleV = (float)1f / curTexData.height;

        for (int i = 0; i < numEdgeVertices; i++) {
            leftEnd = leftEdgeStep * (float)i;
            leftEnd += vertices[0];
            rightEnd = rightEdgeStep * (float)i;
            rightEnd += vertices[3];

            leftRightSeg = rightEnd - leftEnd;
            leftRightStep = leftRightSeg * subdivideScale;

            for (int j = 0; j < numEdgeVertices; j++) {
                dispVertIndex = curDisp.m_iDispVertStart;
                dispVertIndex += i * numEdgeVertices + j;
                dispVert = bsp.DispVerts[dispVertIndex];

                flatVertex = leftEnd + (leftRightStep * (float)j);

                dispVertex = ToUnityVector(dispVert.m_vVector) * (dispVert.m_flDist /* *scale*/ );
                dispVertex += flatVertex;

                disp_verts.Add(dispVertex);

                var tvi = curTexInfo.textureVecsTexelsPerWorldUnits;

                float tU = Vector3.Dot(flatVertex, new Vector3(tvi[0].x, tvi[0].z, tvi[0].y)) + (curTexInfo.textureVecsTexelsPerWorldUnits[0].w);
                float tV = Vector3.Dot(flatVertex, new Vector3(tvi[1].x, tvi[1].z, tvi[1].y)) + (curTexInfo.textureVecsTexelsPerWorldUnits[1].w);
                UVs.Add(new Vector2(tU * scaleU, tV * scaleV));

                cols.Add(new Color32((byte)(dispVert.m_flAlpha), 0, 0, 0));
            }
        }

        int curIndex;

        for (int i = 0; i < numEdgeVertices - 1; i++) {
            for (int j = 0; j < numEdgeVertices - 1; j++) {
                curIndex = i * numEdgeVertices + j;

                if ((curIndex % 2) == 1) {
                    curIndex += firstVertex;

                    indices.Add(curIndex + 1);
                    indices.Add(curIndex);
                    indices.Add(curIndex + numEdgeVertices);
                    indices.Add(curIndex + numEdgeVertices + 1);
                    indices.Add(curIndex + 1);
                    indices.Add(curIndex + numEdgeVertices);
                } else {
                    curIndex += firstVertex;

                    indices.Add(curIndex);
                    indices.Add(curIndex + numEdgeVertices);
                    indices.Add(curIndex + numEdgeVertices + 1);
                    indices.Add(curIndex + 1);
                    indices.Add(curIndex);
                    indices.Add(curIndex + numEdgeVertices + 1);
                }
            }
        }

        /*for (int i = 0; i < disp_verts.Count; i++) {
            disp_verts[i] *= uSrcSettings.Inst.worldScale;
        }*/

        surface f = new surface();
        f.index = faceIndex;
        //f.flags = flags;

        f.dispinfo = dispinfoId;

        f.points = disp_verts.ToArray();
        f.uv = UVs.ToArray();
        //f.uv2 = UV2s;
        f.cols = cols.ToArray();
        f.triangles = indices.ToArray();

        //f.lightMapW = lightmapW;
        //f.lightMapH = lightmapH;

        return f;
    }



    GameObject LoadModel(SourceBSP bsp, dmodel_t model, bool skipSky, Transform parent = null)
    {

        var matPath = AssetDatabase.FindAssets("DefaultBspMaterial");
        var assetPath = AssetDatabase.GUIDToAssetPath(matPath[0]);

        var mat = AssetDatabase.LoadAssetAtPath<Material>(assetPath);

        var result = CreateGameObject("BspModel", parent);
        var meshFilter = result.GetComponent<MeshFilter>();
        var meshRenderer = result.GetComponent<MeshRenderer>();
     
        var mesh = meshFilter.sharedMesh;

        List<short> tex = new List<short>();

        List<Vector3> vertices = new List<Vector3>();
        List<int> triangles = new List<int>();

        int dispCount = 0;

        for (int i = 0; i < model.numfaces; ++i) {
            int faceId = i + model.firstface;
            var face = bsp.Faces[faceId];

            var faceTexInfo = bsp.Texinfo[face.texinfo];

            if(skipSky && ((faceTexInfo.flags & SourceBSPStructs.SurfaceFlags.SURF_SKY) != 0)) {
                continue;
            }

            var vertexIndexOffset = vertices.Count;
            if (face.dispinfo == -1) {
               
                if (face.numedges != 0) {
                   
                    var faceVertexIds = GetFaceVertexIds(bsp, face);
                    var verticesCount = faceVertexIds.Count;

                    for (int v = 0; v < faceVertexIds.Count; ++v) {
                        var srcVertex = bsp.Vertexes[faceVertexIds[v]];
                        vertices.Add(new Vector3(srcVertex.x, srcVertex.z, srcVertex.y));
                    }

                    int trianglesCount = verticesCount - 2;
                    int indicesCount = trianglesCount * 3;

                    //int[] indices = new int[indicesCount];
                    for (int t = 0; t < trianglesCount; ++t) {
                        triangles.Add(vertexIndexOffset + 0);
                        triangles.Add(vertexIndexOffset + (t + 1));
                        triangles.Add(vertexIndexOffset + (t + 2));
                    }


                    //Debug.Log($"Vertex IDs count: {faceVertexIds.Count} Edges count: {face.numedges}");
                    // break; //TEST!!! Only first face
                } else {
                    Debug.Log("Face without edges");
                }
            } else {
                var dispSurface = BuildDispFace(bsp, faceId);

                for(int t = 0; t< dispSurface.triangles.Length; ++t) {
                    dispSurface.triangles[t] += vertexIndexOffset;
                }
                triangles.AddRange(dispSurface.triangles);

                vertices.AddRange(dispSurface.points);

                dispCount++;
               /* if (dispCount >= 800) {
                    break;
                }*/
               
            }

           

        }

 
        Debug.Log("Index format: " + mesh.indexFormat);
        mesh.indexFormat = UnityEngine.Rendering.IndexFormat.UInt32;


        vertices = vertices.Select(v => v * _worldScale).ToList();
        mesh.vertices = vertices.ToArray();
        mesh.triangles = triangles.ToArray();
        mesh.RecalculateBounds();
        mesh.RecalculateNormals();

        meshRenderer.sharedMaterials = new Material[] { mat };

        //Debug.Log($"Texinfos count: {tex.Count} Distinct: {tex.Distinct().Count()}") ;


        return result;
    }

    private bool SkipSky = true;
    private bool LoadProps = true;

    void LoadProp()
    {

    }

    private string _gameDir = @"C:\Program Files (x86)\Steam\steamapps\common\Counter-Strike Global Offensive\csgo";
    private string GameMapsDir => System.IO.Path.Combine(_gameDir, "maps");

    private string MapFilePath(string mapName)
    {
        return System.IO.Path.Combine(GameMapsDir, mapName + ".bsp");
    }


    GameObject CreateCubeGameObject(string name, Transform parent = null)
    {
        var result = GameObject.CreatePrimitive(PrimitiveType.Cube);
        result.name = name;
        if (parent != null) {
            result.transform.parent = parent;
        }
        result.transform.localPosition = Vector3.zero;
        result.transform.localRotation = Quaternion.identity;
        result.transform.localScale = Vector3.one;
        return result;
    }


    private void LoadStaticProp(StaticPropLumpV11_t prop, List<VPKFile.ExtensionRecord> tree, Transform propsRoot, dgamelumpheader_t game)
    {
        var propType = prop.m_PropType;
        var propName = game.staticPropNames[propType];

        GameObject propObject = CreateGameObject(propName.m_Name, propsRoot.transform);

        propObject.transform.localPosition = ToUnityVector(prop.m_Origin) * _worldScale;
        propObject.transform.localRotation = Quaternion.Euler(-prop.m_Angles.z, -prop.m_Angles.y, -prop.m_Angles.x);


        if (prop.m_UniformScale != 0.0f) {
            propObject.transform.localScale = new Vector3(prop.m_UniformScale, prop.m_UniformScale, prop.m_UniformScale);
        }


        var fileRecord = VPKFile.FindFile(tree, propName.m_Name);
        if (fileRecord != null) {




            SourceStudioModel model = new SourceStudioModel();
            model.Load(propName.m_Name, (string path) => {
                var fileRecord = VPKFile.FindFile(tree, path);
                var propData = VPKFile.ReadFile(_gameDir, "pak01", fileRecord);
                Debug.Log("Loading file: " + path + " Size: " + propData.Length);

                MemoryStream propDataStream = new MemoryStream(propData);
                return propDataStream;
            });

            Debug.Log("Model loaded");


            model.GetInstance(propObject, false, 0);
            // SourceMDL mdl = new SourceMDL(propDataStream, false);

            // mdl.Header.


        }
    }

    void OnGUI()
    {


        SkipSky = GUILayout.Toggle(SkipSky, "Skip sky");

        LoadProps = GUILayout.Toggle(LoadProps, "Load props");

        if (GUILayout.Button("Import")) {




            string mapName = "de_inferno"; // "de_dust2";  //de_inferno


            GameObject mapRoot = CreateGameObject(mapName);


            SourceBSP bsp = new SourceBSP(MapFilePath(mapName));

            LoadModel(bsp, bsp.Models[0], SkipSky, mapRoot.transform);
            /*foreach(var model in bsp.Models) {
                if(model.numfaces != 0) {
                    LoadModel(bsp, model, SkipSky);
                } else {
                    Debug.Log("WTF");
                }
            }*/


            var game = bsp.GameLump;
            var tree = VPKFile.ReadDirTree(System.IO.Path.Combine(_gameDir, "pak01_dir.vpk"));


            if (LoadProps) {
                var staticProps = (SourceFormatParser.BSP.SourceBSPStructs.StaticPropLumpV11_t[])game.staticProps;
                GameObject propsRoot = CreateGameObject("Props", mapRoot.transform);
                foreach (var prop in staticProps) {
                    LoadStaticProp(prop, tree, propsRoot.transform, game);
                }
            }

        }
    }
}