import {
  AmbientLight,
  AnimationClip,
  Bone,
  BufferGeometry,
  ClampToEdgeWrapping,
  Color,
  DirectionalLight,
  EquirectangularReflectionMapping,
  Euler,
  FileLoader,
  Float32BufferAttribute,
  Group,
  Line,
  LineBasicMaterial,
  Loader,
  LoaderUtils,
  MathUtils,
  Matrix3,
  Matrix4,
  Mesh,
  MeshLambertMaterial,
  MeshPhongMaterial,
  NumberKeyframeTrack,
  Object3D,
  OrthographicCamera,
  PerspectiveCamera,
  PointLight,
  PropertyBinding,
  Quaternion,
  QuaternionKeyframeTrack,
  RepeatWrapping,
  Skeleton,
  SkinnedMesh,
  SpotLight,
  Texture,
  TextureLoader,
  Uint16BufferAttribute,
  Vector3,
  Vector4,
  VectorKeyframeTrack,
  SRGBColorSpace,
} from "three";
import * as fflate from "../public/libs/fflate.module";
import { NURBSCurve } from "../public/curves/NURBSCurve.js";

/**
 * Loader loads FBX file and generates Group representing FBX scene.
 * Requires FBX file to be >= 7.0 and in ASCII or >= 6400 in Binary format
 * Versions lower than this may load but will probably have errors
 *
 * Needs Support:
 *  Morph normals / blend shape normals
 *
 * FBX format references:
 * 	https://help.autodesk.com/view/FBX/2017/ENU/?guid=__cpp_ref_index_html (C++ SDK reference)
 *
 * Binary format specification:
 *	https://code.blender.org/2013/08/fbx-binary-file-format-specification/
 */

let fbxTree;
let connections;
let sceneGraph;

class FBXLoader extends Loader {
  constructor(manager) {
    super(manager);
  }

  load(url, onLoad, onProgress, onError) {
    const scope = this;

    const path =
      scope.path === "" ? LoaderUtils.extractUrlBase(url) : scope.path;

    const loader = new FileLoader(this.manager);
    loader.setPath(scope.path);
    loader.setResponseType("arraybuffer");
    loader.setRequestHeader(scope.requestHeader);
    loader.setWithCredentials(scope.withCredentials);

    loader.load(
      url,
      function (buffer) {
        try {
          onLoad(scope.parse(buffer, path));
        } catch (e) {
          if (onError) {
            onError(e);
          } else {
            console.error(e);
          }

          scope.manager.itemError(url);
        }
      },
      onProgress,
      onError
    );
  }

  parse(FBXBuffer, path) {
    if (isFbxFormatBinary(FBXBuffer)) {
      fbxTree = new BinaryParser().parse(FBXBuffer);
    } else {
      const FBXText = convertArrayBufferToString(FBXBuffer);

      if (!isFbxFormatASCII(FBXText)) {
        throw new Error("THREE.FBXLoader: Unknown format.");
      }

      if (getFbxVersion(FBXText) < 7000) {
        throw new Error(
          "THREE.FBXLoader: FBX version not supported, FileVersion: " +
            getFbxVersion(FBXText)
        );
      }

      fbxTree = new TextParser().parse(FBXText);
    }

    // console.log( fbxTree );

    const textureLoader = new TextureLoader(this.manager)
      .setPath(this.resourcePath || path)
      .setCrossOrigin(this.crossOrigin);

    return new FBXTreeParser(textureLoader, this.manager).parse(fbxTree);
  }
}

// Parse the FBXTree object returned by the BinaryParser or TextParser and return a Group
class FBXTreeParser {
  constructor(textureLoader, manager) {
    this.textureLoader = textureLoader;
    this.manager = manager;
  }

  parse() {
    connections = this.parseConnections();

    const images = this.parseImages();
    const textures = this.parseTextures(images);
    const materials = this.parseMaterials(textures);
    const deformers = this.parseDeformers();
    const geometryMap = new GeometryParser().parse(deformers);

    this.parseScene(deformers, geometryMap, materials);

    return sceneGraph;
  }

  // Parses FBXTree.Connections which holds parent-child connections between objects (e.g. material -> texture, model->geometry )
  // and details the connection type
  parseConnections() {
    const connectionMap = new Map();

    if ("Connections" in fbxTree) {
      const rawConnections = fbxTree.Connections.connections;

      rawConnections.forEach(function (rawConnection) {
        const fromID = rawConnection[0];
        const toID = rawConnection[1];
        const relationship = rawConnection[2];

        if (!connectionMap.has(fromID)) {
          connectionMap.set(fromID, {
            parents: [],
            children: [],
          });
        }

        const parentRelationship = { ID: toID, relationship: relationship };
        connectionMap.get(fromID).parents.push(parentRelationship);

        if (!connectionMap.has(toID)) {
          connectionMap.set(toID, {
            parents: [],
            children: [],
          });
        }

        const childRelationship = { ID: fromID, relationship: relationship };
        connectionMap.get(toID).children.push(childRelationship);
      });
    }

    return connectionMap;
  }

  // Parse FBXTree.Objects.Video for embedded image data
  // These images are connected to textures in FBXTree.Objects.Textures
  // via FBXTree.Connections.
  parseImages() {
    const images = {};
    const blobs = {};

    if ("Video" in fbxTree.Objects) {
      const videoNodes = fbxTree.Objects.Video;

      for (const nodeID in videoNodes) {
        const videoNode = videoNodes[nodeID];

        const id = parseInt(nodeID);

        images[id] = videoNode.RelativeFilename || videoNode.Filename;

        // raw image data is in videoNode.Content
        if ("Content" in videoNode) {
          const arrayBufferContent =
            videoNode.Content instanceof ArrayBuffer &&
            videoNode.Content.byteLength > 0;
          const base64Content =
            typeof videoNode.Content === "string" && videoNode.Content !== "";

          if (arrayBufferContent || base64Content) {
            const image = this.parseImage(videoNodes[nodeID]);

            blobs[videoNode.RelativeFilename || videoNode.Filename] = image;
          }
        }
      }
    }

    for (const id in images) {
      const filename = images[id];

      if (blobs[filename] !== undefined) images[id] = blobs[filename];
      else images[id] = images[id].split("\\").pop();
    }

    return images;
  }

  // Parse embedded image data in FBXTree.Video.Content
  parseImage(videoNode) {
    const content = videoNode.Content;
    const fileName = videoNode.RelativeFilename || videoNode.Filename;
    const extension = fileName
      .slice(fileName.lastIndexOf(".") + 1)
      .toLowerCase();

    let type;

    switch (extension) {
      case "bmp":
        type = "image/bmp";
        break;

      case "jpg":
      case "jpeg":
        type = "image/jpeg";
        break;

      case "png":
        type = "image/png";
        break;

      case "tif":
        type = "image/tiff";
        break;

      case "tga":
        if (this.manager.getHandler(".tga") === null) {
          console.warn("FBXLoader: TGA loader not found, skipping ", fileName);
        }

        type = "image/tga";
        break;

      default:
        console.warn(
          'FBXLoader: Image type "' + extension + '" is not supported.'
        );
        return;
    }

    if (typeof content === "string") {
      // ASCII format

      return "data:" + type + ";base64," + content;
    } else {
      // Binary Format

      const array = new Uint8Array(content);
      return window.URL.createObjectURL(new Blob([array], { type: type }));
    }
  }

  // Parse nodes in FBXTree.Objects.Texture
  // These contain details such as UV scaling, cropping, rotation etc and are connected
  // to images in FBXTree.Objects.Video
  parseTextures(images) {
    const textureMap = new Map();

    if ("Texture" in fbxTree.Objects) {
      const textureNodes = fbxTree.Objects.Texture;
      for (const nodeID in textureNodes) {
        const texture = this.parseTexture(textureNodes[nodeID], images);
        textureMap.set(parseInt(nodeID), texture);
      }
    }

    return textureMap;
  }

  // Parse individual node in FBXTree.Objects.Texture
  parseTexture(textureNode, images) {
    const texture = this.loadTexture(textureNode, images);

    texture.ID = textureNode.id;

    texture.name = textureNode.attrName;

    const wrapModeU = textureNode.WrapModeU;
    const wrapModeV = textureNode.WrapModeV;

    const valueU = wrapModeU !== undefined ? wrapModeU.value : 0;
    const valueV = wrapModeV !== undefined ? wrapModeV.value : 0;

    // http://download.autodesk.com/us/fbx/SDKdocs/FBX_SDK_Help/files/fbxsdkref/class_k_fbx_texture.html#889640e63e2e681259ea81061b85143a
    // 0: repeat(default), 1: clamp

    texture.wrapS = valueU === 0 ? RepeatWrapping : ClampToEdgeWrapping;
    texture.wrapT = valueV === 0 ? RepeatWrapping : ClampToEdgeWrapping;

    if ("Scaling" in textureNode) {
      const values = textureNode.Scaling.value;

      texture.repeat.x = values[0];
      texture.repeat.y = values[1];
    }

    if ("Translation" in textureNode) {
      const values = textureNode.Translation.value;

      texture.offset.x = values[0];
      texture.offset.y = values[1];
    }

    return texture;
  }

  // load a texture specified as a blob or data URI, or via an external URL using TextureLoader
  loadTexture(textureNode, images) {
    let fileName;

    const currentPath = this.textureLoader.path;

    const children = connections.get(textureNode.id).children;

    if (
      children !== undefined &&
      children.length > 0 &&
      images[children[0].ID] !== undefined
    ) {
      fileName = images[children[0].ID];

      if (fileName.indexOf("blob:") === 0 || fileName.indexOf("data:") === 0) {
        this.textureLoader.setPath(undefined);
      }
    }

    let texture;

    const extension = textureNode.FileName.slice(-3).toLowerCase();

    if (extension === "tga") {
      const loader = this.manager.getHandler(".tga");

      if (loader === null) {
        console.warn(
          "FBXLoader: TGA loader not found, creating placeholder texture for",
          textureNode.RelativeFilename
        );
        texture = new Texture();
      } else {
        loader.setPath(this.textureLoader.path);
        texture = loader.load(fileName);
      }
    } else if (extension === "psd") {
      console.warn(
        "FBXLoader: PSD textures are not supported, creating placeholder texture for",
        textureNode.RelativeFilename
      );
      texture = new Texture();
    } else {
      texture = this.textureLoader.load(fileName);
    }

    this.textureLoader.setPath(currentPath);

    return texture;
  }

  // Parse nodes in FBXTree.Objects.Material
  parseMaterials(textureMap) {
    const materialMap = new Map();

    if ("Material" in fbxTree.Objects) {
      const materialNodes = fbxTree.Objects.Material;

      for (const nodeID in materialNodes) {
        const material = this.parseMaterial(materialNodes[nodeID], textureMap);

        if (material !== null) materialMap.set(parseInt(nodeID), material);
      }
    }

    return materialMap;
  }

  // Parse single node in FBXTree.Objects.Material
  // Materials are connected to texture maps in FBXTree.Objects.Textures
  // FBX format currently only supports Lambert and Phong shading models
  parseMaterial(materialNode, textureMap) {
    const ID = materialNode.id;
    const name = materialNode.attrName;
    let type = materialNode.ShadingModel;

    // Case where FBX wraps shading model in property object.
    if (typeof type === "object") {
      type = type.value;
    }

    // Ignore unused materials which don't have any connections.
    if (!connections.has(ID)) return null;

    const parameters = this.parseParameters(materialNode, textureMap, ID);

    let material;

    switch (type.toLowerCase()) {
      case "phong":
        material = new MeshPhongMaterial();
        break;
      case "lambert":
        material = new MeshLambertMaterial();
        break;
      default:
        console.warn(
          'THREE.FBXLoader: unknown material type "%s". Defaulting to MeshPhongMaterial.',
          type
        );
        material = new MeshPhongMaterial();
        break;
    }

    material.setValues(parameters);
    material.name = name;

    return material;
  }

  // Parse FBX material and return parameters suitable for a three.js material
  // Also parse the texture map and return any textures associated with the material
  parseParameters(materialNode, textureMap, ID) {
    const parameters = {};

    if (materialNode.BumpFactor) {
      parameters.bumpScale = materialNode.BumpFactor.value;
    }

    if (materialNode.Diffuse) {
      parameters.color = new Color()
        .fromArray(materialNode.Diffuse.value)
        .convertSRGBToLinear();
    } else if (
      materialNode.DiffuseColor &&
      (materialNode.DiffuseColor.type === "Color" ||
        materialNode.DiffuseColor.type === "ColorRGB")
    ) {
      // The blender exporter exports diffuse here instead of in materialNode.Diffuse
      parameters.color = new Color()
        .fromArray(materialNode.DiffuseColor.value)
        .convertSRGBToLinear();
    }

    if (materialNode.DisplacementFactor) {
      parameters.displacementScale = materialNode.DisplacementFactor.value;
    }

    if (materialNode.Emissive) {
      parameters.emissive = new Color()
        .fromArray(materialNode.Emissive.value)
        .convertSRGBToLinear();
    } else if (
      materialNode.EmissiveColor &&
      (materialNode.EmissiveColor.type === "Color" ||
        materialNode.EmissiveColor.type === "ColorRGB")
    ) {
      // The blender exporter exports emissive color here instead of in materialNode.Emissive
      parameters.emissive = new Color()
        .fromArray(materialNode.EmissiveColor.value)
        .convertSRGBToLinear();
    }

    if (materialNode.EmissiveFactor) {
      parameters.emissiveIntensity = parseFloat(
        materialNode.EmissiveFactor.value
      );
    }

    if (materialNode.Opacity) {
      parameters.opacity = parseFloat(materialNode.Opacity.value);
    }

    if (parameters.opacity < 1.0) {
      parameters.transparent = true;
    }

    if (materialNode.ReflectionFactor) {
      parameters.reflectivity = materialNode.ReflectionFactor.value;
    }

    if (materialNode.Shininess) {
      parameters.shininess = materialNode.Shininess.value;
    }

    if (materialNode.Specular) {
      parameters.specular = new Color()
        .fromArray(materialNode.Specular.value)
        .convertSRGBToLinear();
    } else if (
      materialNode.SpecularColor &&
      materialNode.SpecularColor.type === "Color"
    ) {
      // The blender exporter exports specular color here instead of in materialNode.Specular
      parameters.specular = new Color()
        .fromArray(materialNode.SpecularColor.value)
        .convertSRGBToLinear();
    }

    const scope = this;
    connections.get(ID).children.forEach(function (child) {
      const type = child.relationship;

      switch (type) {
        case "Bump":
          parameters.bumpMap = scope.getTexture(textureMap, child.ID);
          break;

        case "Maya|TEX_ao_map":
          parameters.aoMap = scope.getTexture(textureMap, child.ID);
          break;

        case "DiffuseColor":
        case "Maya|TEX_color_map":
          parameters.map = scope.getTexture(textureMap, child.ID);
          if (parameters.map !== undefined) {
            parameters.map.colorSpace = SRGBColorSpace;
          }

          break;

        case "DisplacementColor":
          parameters.displacementMap = scope.getTexture(textureMap, child.ID);
          break;

        case "EmissiveColor":
          parameters.emissiveMap = scope.getTexture(textureMap, child.ID);
          if (parameters.emissiveMap !== undefined) {
            parameters.emissiveMap.colorSpace = SRGBColorSpace;
          }

          break;

        case "NormalMap":
        case "Maya|TEX_normal_map":
          parameters.normalMap = scope.getTexture(textureMap, child.ID);
          break;

        case "ReflectionColor":
          parameters.envMap = scope.getTexture(textureMap, child.ID);
          if (parameters.envMap !== undefined) {
            parameters.envMap.mapping = EquirectangularReflectionMapping;
            parameters.envMap.colorSpace = SRGBColorSpace;
          }

          break;

        case "SpecularColor":
          parameters.specularMap = scope.getTexture(textureMap, child.ID);
          if (parameters.specularMap !== undefined) {
            parameters.specularMap.colorSpace = SRGBColorSpace;
          }

          break;

        case "TransparentColor":
        case "TransparencyFactor":
          parameters.alphaMap = scope.getTexture(textureMap, child.ID);
          parameters.transparent = true;
          break;

        case "AmbientColor":
        case "ShininessExponent": // AKA glossiness map
        case "SpecularFactor": // AKA specularLevel
        case "VectorDisplacementColor": // NOTE: Seems to be a copy of DisplacementColor
        default:
          console.warn(
            "THREE.FBXLoader: %s map is not supported in three.js, skipping texture.",
            type
          );
          break;
      }
    });

    return parameters;
  }

  // get a texture from the textureMap for use by a material.
  getTexture(textureMap, id) {
    // if the texture is a layered texture, just use the first layer and issue a warning
    if (
      "LayeredTexture" in fbxTree.Objects &&
      id in fbxTree.Objects.LayeredTexture
    ) {
      console.warn(
        "THREE.FBXLoader: layered textures are not supported in three.js. Discarding all but first layer."
      );
      id = connections.get(id).children[0].ID;
    }

    return textureMap.get(id);
  }

  // Parse nodes in FBXTree.Objects.Deformer
  // Deformer node can contain skinning or Vertex Cache animation data, however only skinning is supported here
  // Generates map of Skeleton-like objects for use later when generating and binding skeletons.
  parseDeformers() {
    const skeletons = {};
    const morphTargets = {};

    if ("Deformer" in fbxTree.Objects) {
      const DeformerNodes = fbxTree.Objects.Deformer;

      for (const nodeID in DeformerNodes) {
        const deformerNode = DeformerNodes[nodeID];

        const relationships = connections.get(parseInt(nodeID));

        if (deformerNode.attrType === "Skin") {
          const skeleton = this.parseSkeleton(relationships, DeformerNodes);
          skeleton.ID = nodeID;

          if (relationships.parents.length > 1)
            console.warn(
              "THREE.FBXLoader: skeleton attached to more than one geometry is not supported."
            );
          skeleton.geometryID = relationships.parents[0].ID;

          skeletons[nodeID] = skeleton;
        } else if (deformerNode.attrType === "BlendShape") {
          const morphTarget = {
            id: nodeID,
          };

          morphTarget.rawTargets = this.parseMorphTargets(
            relationships,
            DeformerNodes
          );
          morphTarget.id = nodeID;

          if (relationships.parents.length > 1)
            console.warn(
              "THREE.FBXLoader: morph target attached to more than one geometry is not supported."
            );

          morphTargets[nodeID] = morphTarget;
        }
      }
    }

    return {
      skeletons: skeletons,
      morphTargets: morphTargets,
    };
  }

  // Parse single nodes in FBXTree.Objects.Deformer
  // The top level skeleton node has type 'Skin' and sub nodes have type 'Cluster'
  // Each skin node represents a skeleton and each cluster node represents a bone
  parseSkeleton(relationships, deformerNodes) {
    const rawBones = [];

    relationships.children.forEach(function (child) {
      const boneNode = deformerNodes[child.ID];

      if (boneNode.attrType !== "Cluster") return;

      const rawBone = {
        ID: child.ID,
        indices: [],
        weights: [],
        transformLink: new Matrix4().fromArray(boneNode.TransformLink.a),
        // transform: new Matrix4().fromArray( boneNode.Transform.a ),
        // linkMode: boneNode.Mode,
      };

      if ("Indexes" in boneNode) {
        rawBone.indices = boneNode.Indexes.a;
        rawBone.weights = boneNode.Weights.a;
      }

      rawBones.push(rawBone);
    });

    return {
      rawBones: rawBones,
      bones: [],
    };
  }

  // The top level morph deformer node has type "BlendShape" and sub nodes have type "BlendShapeChannel"
  parseMorphTargets(relationships, deformerNodes) {
    const rawMorphTargets = [];

    for (let i = 0; i < relationships.children.length; i++) {
      const child = relationships.children[i];

      const morphTargetNode = deformerNodes[child.ID];

      const rawMorphTarget = {
        name: morphTargetNode.attrName,
        initialWeight: morphTargetNode.DeformPercent,
        id: morphTargetNode.id,
        fullWeights: morphTargetNode.FullWeights.a,
      };

      if (morphTargetNode.attrType !== "BlendShapeChannel") return;

      rawMorphTarget.geoID = connections
        .get(parseInt(child.ID))
        .children.filter(function (child) {
          return child.relationship === undefined;
        })[0].ID;

      rawMorphTargets.push(rawMorphTarget);
    }

    return rawMorphTargets;
  }

  // create the main Group() to be returned by the loader
  parseScene(deformers, geometryMap, materialMap) {
    sceneGraph = new Group();

    const modelMap = this.parseModels(
      deformers.skeletons,
      geometryMap,
      materialMap
    );

    const modelNodes = fbxTree.Objects.Model;

    const scope = this;
    modelMap.forEach(function (model) {
      const modelNode = modelNodes[model.ID];
      scope.setLookAtProperties(model, modelNode);

      const parentConnections = connections.get(model.ID).parents;

      parentConnections.forEach(function (connection) {
        const parent = modelMap.get(connection.ID);
        if (parent !== undefined) parent.add(model);
      });

      if (model.parent === null) {
        sceneGraph.add(model);
      }
    });

    this.bindSkeleton(deformers.skeletons, geometryMap, modelMap);

    this.createAmbientLight();

    sceneGraph.traverse(function (node) {
      if (node.userData.transformData) {
        if (node.parent) {
          node.userData.transformData.parentMatrix = node.parent.matrix;
          node.userData.transformData.parentMatrixWorld =
            node.parent.matrixWorld;
        }

        const transform = generateTransform(node.userData.transformData);

        node.applyMatrix4(transform);
        node.updateWorldMatrix();
      }
    });

    const animations = new AnimationParser().parse();

    // if all the models where already combined in a single group, just return that
    if (sceneGraph.children.length === 1 && sceneGraph.children[0].isGroup) {
      sceneGraph.children[0].animations = animations;
      sceneGraph = sceneGraph.children[0];
    }

    sceneGraph.animations = animations;
  }

  // parse nodes in FBXTree.Objects.Model
  parseModels(skeletons, geometryMap, materialMap) {
    const modelMap = new Map();
    const modelNodes = fbxTree.Objects.Model;

    for (const nodeID in modelNodes) {
      const id = parseInt(nodeID);
      const node = modelNodes[nodeID];
      const relationships = connections.get(id);

      let model = this.buildSkeleton(
        relationships,
        skeletons,
        id,
        node.attrName
      );

      if (!model) {
        switch (node.attrType) {
          case "Camera":
            model = this.createCamera(relationships);
            break;
          case "Light":
            model = this.createLight(relationships);
            break;
          case "Mesh":
            model = this.createMesh(relationships, geometryMap, materialMap);
            break;
          case "NurbsCurve":
            model = this.createCurve(relationships, geometryMap);
            break;
          case "LimbNode":
          case "Root":
            model = new Bone();
            break;
          case "Null":
          default:
            model = new Group();
            break;
        }

        model.name = node.attrName
          ? PropertyBinding.sanitizeNodeName(node.attrName)
          : "";

        model.ID = id;
      }

      this.getTransformData(model, node);
      modelMap.set(id, model);
    }

    return modelMap;
  }

  buildSkeleton(relationships, skeletons, id, name) {
    let bone = null;

    relationships.parents.forEach(function (parent) {
      for (const ID in skeletons) {
        const skeleton = skeletons[ID];

        skeleton.rawBones.forEach(function (rawBone, i) {
          if (rawBone.ID === parent.ID) {
            const subBone = bone;
            bone = new Bone();

            bone.matrixWorld.copy(rawBone.transformLink);

            // set name and id here - otherwise in cases where "subBone" is created it will not have a name / id

            bone.name = name ? PropertyBinding.sanitizeNodeName(name) : "";
            bone.ID = id;

            skeleton.bones[i] = bone;

            // In cases where a bone is shared between multiple meshes
            // duplicate the bone here and and it as a child of the first bone
            if (subBone !== null) {
              bone.add(subBone);
            }
          }
        });
      }
    });

    return bone;
  }

  // create a PerspectiveCamera or OrthographicCamera
  createCamera(relationships) {
    let model;
    let cameraAttribute;

    relationships.children.forEach(function (child) {
      const attr = fbxTree.Objects.NodeAttribute[child.ID];

      if (attr !== undefined) {
        cameraAttribute = attr;
      }
    });

    if (cameraAttribute === undefined) {
      model = new Object3D();
    } else {
      let type = 0;
      if (
        cameraAttribute.CameraProjectionType !== undefined &&
        cameraAttribute.CameraProjectionType.value === 1
      ) {
        type = 1;
      }

      let nearClippingPlane = 1;
      if (cameraAttribute.NearPlane !== undefined) {
        nearClippingPlane = cameraAttribute.NearPlane.value / 1000;
      }

      let farClippingPlane = 1000;
      if (cameraAttribute.FarPlane !== undefined) {
        farClippingPlane = cameraAttribute.FarPlane.value / 1000;
      }

      let width = window.innerWidth;
      let height = window.innerHeight;

      if (
        cameraAttribute.AspectWidth !== undefined &&
        cameraAttribute.AspectHeight !== undefined
      ) {
        width = cameraAttribute.AspectWidth.value;
        height = cameraAttribute.AspectHeight.value;
      }

      const aspect = width / height;

      let fov = 45;
      if (cameraAttribute.FieldOfView !== undefined) {
        fov = cameraAttribute.FieldOfView.value;
      }

      const focalLength = cameraAttribute.FocalLength
        ? cameraAttribute.FocalLength.value
        : null;

      switch (type) {
        case 0: // Perspective
          model = new PerspectiveCamera(
            fov,
            aspect,
            nearClippingPlane,
            farClippingPlane
          );
          if (focalLength !== null) model.setFocalLength(focalLength);
          break;

        case 1: // Orthographic
          model = new OrthographicCamera(
            -width / 2,
            width / 2,
            height / 2,
            -height / 2,
            nearClippingPlane,
            farClippingPlane
          );
          break;

        default:
          console.warn("THREE.FBXLoader: Unknown camera type " + type + ".");
          model = new Object3D();
          break;
      }
    }

    return model;
  }

  // Create a DirectionalLight, PointLight or SpotLight
  createLight(relationships) {
    let model;
    let lightAttribute;

    relationships.children.forEach(function (child) {
      const attr = fbxTree.Objects.NodeAttribute[child.ID];

      if (attr !== undefined) {
        lightAttribute = attr;
      }
    });

    if (lightAttribute === undefined) {
      model = new Object3D();
    } else {
      let type;

      // LightType can be undefined for Point lights
      if (lightAttribute.LightType === undefined) {
        type = 0;
      } else {
        type = lightAttribute.LightType.value;
      }

      let color = 0xffffff;

      if (lightAttribute.Color !== undefined) {
        color = new Color()
          .fromArray(lightAttribute.Color.value)
          .convertSRGBToLinear();
      }

      let intensity =
        lightAttribute.Intensity === undefined
          ? 1
          : lightAttribute.Intensity.value / 100;

      // light disabled
      if (
        lightAttribute.CastLightOnObject !== undefined &&
        lightAttribute.CastLightOnObject.value === 0
      ) {
        intensity = 0;
      }

      let distance = 0;
      if (lightAttribute.FarAttenuationEnd !== undefined) {
        if (
          lightAttribute.EnableFarAttenuation !== undefined &&
          lightAttribute.EnableFarAttenuation.value === 0
        ) {
          distance = 0;
        } else {
          distance = lightAttribute.FarAttenuationEnd.value;
        }
      }

      // TODO: could this be calculated linearly from FarAttenuationStart to FarAttenuationEnd?
      const decay = 1;

      switch (type) {
        case 0: // Point
          model = new PointLight(color, intensity, distance, decay);
          break;

        case 1: // Directional
          model = new DirectionalLight(color, intensity);
          break;

        case 2: // Spot
          let angle = Math.PI / 3;

          if (lightAttribute.InnerAngle !== undefined) {
            angle = MathUtils.degToRad(lightAttribute.InnerAngle.value);
          }

          let penumbra = 0;
          if (lightAttribute.OuterAngle !== undefined) {
            // TODO: this is not correct - FBX calculates outer and inner angle in degrees
            // with OuterAngle > InnerAngle && OuterAngle <= Math.PI
            // while three.js uses a penumbra between (0, 1) to attenuate the inner angle
            penumbra = MathUtils.degToRad(lightAttribute.OuterAngle.value);
            penumbra = Math.max(penumbra, 1);
          }

          model = new SpotLight(
            color,
            intensity,
            distance,
            angle,
            penumbra,
            decay
          );
          break;

        default:
          console.warn(
            "THREE.FBXLoader: Unknown light type " +
              lightAttribute.LightType.value +
              ", defaulting to a PointLight."
          );
          model = new PointLight(color, intensity);
          break;
      }

      if (
        lightAttribute.CastShadows !== undefined &&
        lightAttribute.CastShadows.value === 1
      ) {
        model.castShadow = true;
      }
    }

    return model;
  }

  createMesh(relationships, geometryMap, materialMap) {
    let model;
    let geometry = null;
    let material = null;
    const materials = [];

    // get geometry and materials(s) from connections
    relationships.children.forEach(function (child) {
      if (geometryMap.has(child.ID)) {
        geometry = geometryMap.get(child.ID);
      }

      if (materialMap.has(child.ID)) {
        materials.push(materialMap.get(child.ID));
      }
    });

    if (materials.length > 1) {
      material = materials;
    } else if (materials.length > 0) {
      material = materials[0];
    } else {
      material = new MeshPhongMaterial({
        name: Loader.DEFAULT_MATERIAL_NAME,
        color: 0xcccccc,
      });
      materials.push(material);
    }

    if ("color" in geometry.attributes) {
      materials.forEach(function (material) {
        material.vertexColors = true;
      });
    }

    if (geometry.FBX_Deformer) {
      model = new SkinnedMesh(geometry, material);
      model.normalizeSkinWeights();
    } else {
      model = new Mesh(geometry, material);
    }

    return model;
  }

  createCurve(relationships, geometryMap) {
    const geometry = relationships.children.reduce(function (geo, child) {
      if (geometryMap.has(child.ID)) geo = geometryMap.get(child.ID);

      return geo;
    }, null);

    // FBX does not list materials for Nurbs lines, so we'll just put our own in here.
    const material = new LineBasicMaterial({
      name: Loader.DEFAULT_MATERIAL_NAME,
      color: 0x3300ff,
      linewidth: 1,
    });
    return new Line(geometry, material);
  }

  // parse the model node for transform data
  getTransformData(model, modelNode) {
    const transformData = {};

    if ("InheritType" in modelNode)
      transformData.inheritType = parseInt(modelNode.InheritType.value);

    if ("RotationOrder" in modelNode)
      transformData.eulerOrder = getEulerOrder(modelNode.RotationOrder.value);
    else transformData.eulerOrder = "ZYX";

    if ("Lcl_Translation" in modelNode)
      transformData.translation = modelNode.Lcl_Translation.value;

    if ("PreRotation" in modelNode)
      transformData.preRotation = modelNode.PreRotation.value;
    if ("Lcl_Rotation" in modelNode)
      transformData.rotation = modelNode.Lcl_Rotation.value;
    if ("PostRotation" in modelNode)
      transformData.postRotation = modelNode.PostRotation.value;

    if ("Lcl_Scaling" in modelNode)
      transformData.scale = modelNode.Lcl_Scaling.value;

    if ("ScalingOffset" in modelNode)
      transformData.scalingOffset = modelNode.ScalingOffset.value;
    if ("ScalingPivot" in modelNode)
      transformData.scalingPivot = modelNode.ScalingPivot.value;

    if ("RotationOffset" in modelNode)
      transformData.rotationOffset = modelNode.RotationOffset.value;
    if ("RotationPivot" in modelNode)
      transformData.rotationPivot = modelNode.RotationPivot.value;

    model.userData.transformData = transformData;
  }

  setLookAtProperties(model, modelNode) {
    if ("LookAtProperty" in modelNode) {
      const children = connections.get(model.ID).children;

      children.forEach(function (child) {
        if (child.relationship === "LookAtProperty") {
          const lookAtTarget = fbxTree.Objects.Model[child.ID];

          if ("Lcl_Translation" in lookAtTarget) {
            const pos = lookAtTarget.Lcl_Translation.value;

            // DirectionalLight, SpotLight
            if (model.target !== undefined) {
              model.target.position.fromArray(pos);
              sceneGraph.add(model.target);
            } else {
              // Cameras and other Object3Ds

              model.lookAt(new Vector3().fromArray(pos));
            }
          }
        }
      });
    }
  }

  bindSkeleton(skeletons, geometryMap, modelMap) {
    const bindMatrices = this.parsePoseNodes();

    for (const ID in skeletons) {
      const skeleton = skeletons[ID];

      const parents = connections.get(parseInt(skeleton.ID)).parents;

      parents.forEach(function (parent) {
        if (geometryMap.has(parent.ID)) {
          const geoID = parent.ID;
          const geoRelationships = connections.get(geoID);

          geoRelationships.parents.forEach(function (geoConnParent) {
            if (modelMap.has(geoConnParent.ID)) {
              const model = modelMap.get(geoConnParent.ID);

              model.bind(
                new Skeleton(skeleton.bones),
                bindMatrices[geoConnParent.ID]
              );
            }
          });
        }
      });
    }
  }

  parsePoseNodes() {
    const bindMatrices = {};

    if ("Pose" in fbxTree.Objects) {
      const BindPoseNode = fbxTree.Objects.Pose;

      for (const nodeID in BindPoseNode) {
        if (
          BindPoseNode[nodeID].attrType === "BindPose" &&
          BindPoseNode[nodeID].NbPoseNodes > 0
        ) {
          const poseNodes = BindPoseNode[nodeID].PoseNode;

          if (Array.isArray(poseNodes)) {
            poseNodes.forEach(function (poseNode) {
              bindMatrices[poseNode.Node] = new Matrix4().fromArray(
                poseNode.Matrix.a
              );
            });
          } else {
            bindMatrices[poseNodes.Node] = new Matrix4().fromArray(
              poseNodes.Matrix.a
            );
          }
        }
      }
    }

    return bindMatrices;
  }

  // Parse ambient color in FBXTree.GlobalSettings - if it's not set to black (default), create an ambient light
  createAmbientLight() {
    if (
      "GlobalSettings" in fbxTree &&
      "AmbientColor" in fbxTree.GlobalSettings
    ) {
      const ambientColor = fbxTree.GlobalSettings.AmbientColor.value;
      const r = ambientColor[0];
      const g = ambientColor[1];
      const b = ambientColor[2];

      if (r !== 0 || g !== 0 || b !== 0) {
        const color = new Color(r, g, b).convertSRGBToLinear();
        sceneGraph.add(new AmbientLight(color, 1));
      }
    }
  }
}

// parse Geometry data from FBXTree and return map of BufferGeometries
class GeometryParser {
  constructor() {
    this.negativeMaterialIndices = false;
  }

  // Parse nodes in FBXTree.Objects.Geometry
  parse(deformers) {
    const geometryMap = new Map();

    if ("Geometry" in fbxTree.Objects) {
      const geoNodes = fbxTree.Objects.Geometry;

      for (const nodeID in geoNodes) {
        const relationships = connections.get(parseInt(nodeID));
        const geo = this.parseGeometry(
          relationships,
          geoNodes[nodeID],
          deformers
        );

        geometryMap.set(parseInt(nodeID), geo);
      }
    }

    // report warnings

    if (this.negativeMaterialIndices === true) {
      console.warn(
        "THREE.FBXLoader: The FBX file contains invalid (negative) material indices. The asset might not render as expected."
      );
    }

    return geometryMap;
  }

  // Parse single node in FBXTree.Objects.Geometry
  parseGeometry(relationships, geoNode, deformers) {
    switch (geoNode.attrType) {
      case "Mesh":
        return this.parseMeshGeometry(relationships, geoNode, deformers);
        break;

      case "NurbsCurve":
        return this.parseNurbsGeometry(geoNode);
        break;
    }
  }

  // Parse single node mesh geometry in FBXTree.Objects.Geometry
  parseMeshGeometry(relationships, geoNode, deformers) {
    const skeletons = deformers.skeletons;
    const morphTargets = [];

    const modelNodes = relationships.parents.map(function (parent) {
      return fbxTree.Objects.Model[parent.ID];
    });

    // don't create geometry if it is not associated with any models
    if (modelNodes.length === 0) return;

    const skeleton = relationships.children.reduce(function (skeleton, child) {
      if (skeletons[child.ID] !== undefined) skeleton = skeletons[child.ID];

      return skeleton;
    }, null);

    relationships.children.forEach(function (child) {
      if (deformers.morphTargets[child.ID] !== undefined) {
        morphTargets.push(deformers.morphTargets[child.ID]);
      }
    });

    // Assume one model and get the preRotation from that
    // if there is more than one model associated with the geometry this may cause problems
    const modelNode = modelNodes[0];

    const transformData = {};

    if ("RotationOrder" in modelNode)
      transformData.eulerOrder = getEulerOrder(modelNode.RotationOrder.value);
    if ("InheritType" in modelNode)
      transformData.inheritType = parseInt(modelNode.InheritType.value);

    if ("GeometricTranslation" in modelNode)
      transformData.translation = modelNode.GeometricTranslation.value;
    if ("GeometricRotation" in modelNode)
      transformData.rotation = modelNode.GeometricRotation.value;
    if ("GeometricScaling" in modelNode)
      transformData.scale = modelNode.GeometricScaling.value;

    const transform = generateTransform(transformData);

    return this.genGeometry(geoNode, skeleton, morphTargets, transform);
  }

  // Generate a BufferGeometry from a node in FBXTree.Objects.Geometry
  genGeometry(geoNode, skeleton, morphTargets, preTransform) {
    const geo = new BufferGeometry();
    if (geoNode.attrName) geo.name = geoNode.attrName;

    const geoInfo = this.parseGeoNode(geoNode, skeleton);
    const buffers = this.genBuffers(geoInfo);

    const positionAttribute = new Float32BufferAttribute(buffers.vertex, 3);

    positionAttribute.applyMatrix4(preTransform);

    geo.setAttribute("position", positionAttribute);

    if (buffers.colors.length > 0) {
      geo.setAttribute("color", new Float32BufferAttribute(buffers.colors, 3));
    }

    if (skeleton) {
      geo.setAttribute(
        "skinIndex",
        new Uint16BufferAttribute(buffers.weightsIndices, 4)
      );

      geo.setAttribute(
        "skinWeight",
        new Float32BufferAttribute(buffers.vertexWeights, 4)
      );

      // used later to bind the skeleton to the model
      geo.FBX_Deformer = skeleton;
    }

    if (buffers.normal.length > 0) {
      const normalMatrix = new Matrix3().getNormalMatrix(preTransform);

      const normalAttribute = new Float32BufferAttribute(buffers.normal, 3);
      normalAttribute.applyNormalMatrix(normalMatrix);

      geo.setAttribute("normal", normalAttribute);
    }

    buffers.uvs.forEach(function (uvBuffer, i) {
      const name = i === 0 ? "uv" : `uv${i}`;

      geo.setAttribute(name, new Float32BufferAttribute(buffers.uvs[i], 2));
    });

    if (geoInfo.material && geoInfo.material.mappingType !== "AllSame") {
      // Convert the material indices of each vertex into rendering groups on the geometry.
      let prevMaterialIndex = buffers.materialIndex[0];
      let startIndex = 0;

      buffers.materialIndex.forEach(function (currentIndex, i) {
        if (currentIndex !== prevMaterialIndex) {
          geo.addGroup(startIndex, i - startIndex, prevMaterialIndex);

          prevMaterialIndex = currentIndex;
          startIndex = i;
        }
      });

      // the loop above doesn't add the last group, do that here.
      if (geo.groups.length > 0) {
        const lastGroup = geo.groups[geo.groups.length - 1];
        const lastIndex = lastGroup.start + lastGroup.count;

        if (lastIndex !== buffers.materialIndex.length) {
          geo.addGroup(
            lastIndex,
            buffers.materialIndex.length - lastIndex,
            prevMaterialIndex
          );
        }
      }

      // case where there are multiple materials but the whole geometry is only
      // using one of them
      if (geo.groups.length === 0) {
        geo.addGroup(0, buffers.materialIndex.length, buffers.materialIndex[0]);
      }
    }

    this.addMorphTargets(geo, geoNode, morphTargets, preTransform);

    return geo;
  }

  parseGeoNode(geoNode, skeleton) {
    const geoInfo = {};

    geoInfo.vertexPositions =
      geoNode.Vertices !== undefined ? geoNode.Vertices.a : [];
    geoInfo.vertexIndices =
      geoNode.PolygonVertexIndex !== undefined
        ? geoNode.PolygonVertexIndex.a
        : [];

    if (geoNode.LayerElementColor) {
      geoInfo.color = this.parseVertexColors(geoNode.LayerElementColor[0]);
    }

    if (geoNode.LayerElementMaterial) {
      geoInfo.material = this.parseMaterialIndices(
        geoNode.LayerElementMaterial[0]
      );
    }

    if (geoNode.LayerElementNormal) {
      geoInfo.normal = this.parseNormals(geoNode.LayerElementNormal[0]);
    }

    if (geoNode.LayerElementUV) {
      geoInfo.uv = [];

      let i = 0;
      while (geoNode.LayerElementUV[i]) {
        if (geoNode.LayerElementUV[i].UV) {
          geoInfo.uv.push(this.parseUVs(geoNode.LayerElementUV[i]));
        }

        i++;
      }
    }

    geoInfo.weightTable = {};

    if (skeleton !== null) {
      geoInfo.skeleton = skeleton;

      skeleton.rawBones.forEach(function (rawBone, i) {
        // loop over the bone's vertex indices and weights
        rawBone.indices.forEach(function (index, j) {
          if (geoInfo.weightTable[index] === undefined)
            geoInfo.weightTable[index] = [];

          geoInfo.weightTable[index].push({
            id: i,
            weight: rawBone.weights[j],
          });
        });
      });
    }

    return geoInfo;
  }

  genBuffers(geoInfo) {
    const buffers = {
      vertex: [],
      normal: [],
      colors: [],
      uvs: [],
      materialIndex: [],
      vertexWeights: [],
      weightsIndices: [],
    };

    let polygonIndex = 0;
    let faceLength = 0;
    let displayedWeightsWarning = false;

    // these will hold data for a single face
    let facePositionIndexes = [];
    let faceNormals = [];
    let faceColors = [];
    let faceUVs = [];
    let faceWeights = [];
    let faceWeightIndices = [];

    const scope = this;
    geoInfo.vertexIndices.forEach(function (vertexIndex, polygonVertexIndex) {
      let materialIndex;
      let endOfFace = false;

      // Face index and vertex index arrays are combined in a single array
      // A cube with quad faces looks like this:
      // PolygonVertexIndex: *24 {
      //  a: 0, 1, 3, -3, 2, 3, 5, -5, 4, 5, 7, -7, 6, 7, 1, -1, 1, 7, 5, -4, 6, 0, 2, -5
      //  }
      // Negative numbers mark the end of a face - first face here is 0, 1, 3, -3
      // to find index of last vertex bit shift the index: ^ - 1
      if (vertexIndex < 0) {
        vertexIndex = vertexIndex ^ -1; // equivalent to ( x * -1 ) - 1
        endOfFace = true;
      }

      let weightIndices = [];
      let weights = [];

      facePositionIndexes.push(
        vertexIndex * 3,
        vertexIndex * 3 + 1,
        vertexIndex * 3 + 2
      );

      if (geoInfo.color) {
        const data = getData(
          polygonVertexIndex,
          polygonIndex,
          vertexIndex,
          geoInfo.color
        );

        faceColors.push(data[0], data[1], data[2]);
      }

      if (geoInfo.skeleton) {
        if (geoInfo.weightTable[vertexIndex] !== undefined) {
          geoInfo.weightTable[vertexIndex].forEach(function (wt) {
            weights.push(wt.weight);
            weightIndices.push(wt.id);
          });
        }

        if (weights.length > 4) {
          if (!displayedWeightsWarning) {
            console.warn(
              "THREE.FBXLoader: Vertex has more than 4 skinning weights assigned to vertex. Deleting additional weights."
            );
            displayedWeightsWarning = true;
          }

          const wIndex = [0, 0, 0, 0];
          const Weight = [0, 0, 0, 0];

          weights.forEach(function (weight, weightIndex) {
            let currentWeight = weight;
            let currentIndex = weightIndices[weightIndex];

            Weight.forEach(function (
              comparedWeight,
              comparedWeightIndex,
              comparedWeightArray
            ) {
              if (currentWeight > comparedWeight) {
                comparedWeightArray[comparedWeightIndex] = currentWeight;
                currentWeight = comparedWeight;

                const tmp = wIndex[comparedWeightIndex];
                wIndex[comparedWeightIndex] = currentIndex;
                currentIndex = tmp;
              }
            });
          });

          weightIndices = wIndex;
          weights = Weight;
        }

        // if the weight array is shorter than 4 pad with 0s
        while (weights.length < 4) {
          weights.push(0);
          weightIndices.push(0);
        }

        for (let i = 0; i < 4; ++i) {
          faceWeights.push(weights[i]);
          faceWeightIndices.push(weightIndices[i]);
        }
      }

      if (geoInfo.normal) {
        const data = getData(
          polygonVertexIndex,
          polygonIndex,
          vertexIndex,
          geoInfo.normal
        );

        faceNormals.push(data[0], data[1], data[2]);
      }

      if (geoInfo.material && geoInfo.material.mappingType !== "AllSame") {
        materialIndex = getData(
          polygonVertexIndex,
          polygonIndex,
          vertexIndex,
          geoInfo.material
        )[0];

        if (materialIndex < 0) {
          scope.negativeMaterialIndices = true;
          materialIndex = 0; // fallback
        }
      }

      if (geoInfo.uv) {
        geoInfo.uv.forEach(function (uv, i) {
          const data = getData(
            polygonVertexIndex,
            polygonIndex,
            vertexIndex,
            uv
          );

          if (faceUVs[i] === undefined) {
            faceUVs[i] = [];
          }

          faceUVs[i].push(data[0]);
          faceUVs[i].push(data[1]);
        });
      }

      faceLength++;

      if (endOfFace) {
        if (faceLength > 4)
          console.warn(
            "THREE.FBXLoader: Polygons with more than four sides are not supported. Make sure to triangulate the geometry during export."
          );

        scope.genFace(
          buffers,
          geoInfo,
          facePositionIndexes,
          materialIndex,
          faceNormals,
          faceColors,
          faceUVs,
          faceWeights,
          faceWeightIndices,
          faceLength
        );

        polygonIndex++;
        faceLength = 0;

        // reset arrays for the next face
        facePositionIndexes = [];
        faceNormals = [];
        faceColors = [];
        faceUVs = [];
        faceWeights = [];
        faceWeightIndices = [];
      }
    });

    return buffers;
  }

  // Generate data for a single face in a geometry. If the face is a quad then split it into 2 tris
  genFace(
    buffers,
    geoInfo,
    facePositionIndexes,
    materialIndex,
    faceNormals,
    faceColors,
    faceUVs,
    faceWeights,
    faceWeightIndices,
    faceLength
  ) {
    for (let i = 2; i < faceLength; i++) {
      buffers.vertex.push(geoInfo.vertexPositions[facePositionIndexes[0]]);
      buffers.vertex.push(geoInfo.vertexPositions[facePositionIndexes[1]]);
      buffers.vertex.push(geoInfo.vertexPositions[facePositionIndexes[2]]);

      buffers.vertex.push(
        geoInfo.vertexPositions[facePositionIndexes[(i - 1) * 3]]
      );
      buffers.vertex.push(
        geoInfo.vertexPositions[facePositionIndexes[(i - 1) * 3 + 1]]
      );
      buffers.vertex.push(
        geoInfo.vertexPositions[facePositionIndexes[(i - 1) * 3 + 2]]
      );

      buffers.vertex.push(geoInfo.vertexPositions[facePositionIndexes[i * 3]]);
      buffers.vertex.push(
        geoInfo.vertexPositions[facePositionIndexes[i * 3 + 1]]
      );
      buffers.vertex.push(
        geoInfo.vertexPositions[facePositionIndexes[i * 3 + 2]]
      );

      if (geoInfo.skeleton) {
        buffers.vertexWeights.push(faceWeights[0]);
        buffers.vertexWeights.push(faceWeights[1]);
        buffers.vertexWeights.push(faceWeights[2]);
        buffers.vertexWeights.push(faceWeights[3]);

        buffers.vertexWeights.push(faceWeights[(i - 1) * 4]);
        buffers.vertexWeights.push(faceWeights[(i - 1) * 4 + 1]);
        buffers.vertexWeights.push(faceWeights[(i - 1) * 4 + 2]);
        buffers.vertexWeights.push(faceWeights[(i - 1) * 4 + 3]);

        buffers.vertexWeights.push(faceWeights[i * 4]);
        buffers.vertexWeights.push(faceWeights[i * 4 + 1]);
        buffers.vertexWeights.push(faceWeights[i * 4 + 2]);
        buffers.vertexWeights.push(faceWeights[i * 4 + 3]);

        buffers.weightsIndices.push(faceWeightIndices[0]);
        buffers.weightsIndices.push(faceWeightIndices[1]);
        buffers.weightsIndices.push(faceWeightIndices[2]);
        buffers.weightsIndices.push(faceWeightIndices[3]);

        buffers.weightsIndices.push(faceWeightIndices[(i - 1) * 4]);
        buffers.weightsIndices.push(faceWeightIndices[(i - 1) * 4 + 1]);
        buffers.weightsIndices.push(faceWeightIndices[(i - 1) * 4 + 2]);
        buffers.weightsIndices.push(faceWeightIndices[(i - 1) * 4 + 3]);

        buffers.weightsIndices.push(faceWeightIndices[i * 4]);
        buffers.weightsIndices.push(faceWeightIndices[i * 4 + 1]);
        buffers.weightsIndices.push(faceWeightIndices[i * 4 + 2]);
        buffers.weightsIndices.push(faceWeightIndices[i * 4 + 3]);
      }

      if (geoInfo.color) {
        buffers.colors.push(faceColors[0]);
        buffers.colors.push(faceColors[1]);
        buffers.colors.push(faceColors[2]);

        buffers.colors.push(faceColors[(i - 1) * 3]);
        buffers.colors.push(faceColors[(i - 1) * 3 + 1]);
        buffers.colors.push(faceColors[(i - 1) * 3 + 2]);

        buffers.colors.push(faceColors[i * 3]);
        buffers.colors.push(faceColors[i * 3 + 1]);
        buffers.colors.push(faceColors[i * 3 + 2]);
      }

      if (geoInfo.material && geoInfo.material.mappingType !== "AllSame") {
        buffers.materialIndex.push(materialIndex);
        buffers.materialIndex.push(materialIndex);
        buffers.materialIndex.push(materialIndex);
      }

      if (geoInfo.normal) {
        buffers.normal.push(faceNormals[0]);
        buffers.normal.push(faceNormals[1]);
        buffers.normal.push(faceNormals[2]);

        buffers.normal.push(faceNormals[(i - 1) * 3]);
        buffers.normal.push(faceNormals[(i - 1) * 3 + 1]);
        buffers.normal.push(faceNormals[(i - 1) * 3 + 2]);

        buffers.normal.push(faceNormals[i * 3]);
        buffers.normal.push(faceNormals[i * 3 + 1]);
        buffers.normal.push(faceNormals[i * 3 + 2]);
      }

      if (geoInfo.uv) {
        geoInfo.uv.forEach(function (uv, j) {
          if (buffers.uvs[j] === undefined) buffers.uvs[j] = [];

          buffers.uvs[j].push(faceUVs[j][0]);
          buffers.uvs[j].push(faceUVs[j][1]);

          buffers.uvs[j].push(faceUVs[j][(i - 1) * 2]);
          buffers.uvs[j].push(faceUVs[j][(i - 1) * 2 + 1]);

          buffers.uvs[j].push(faceUVs[j][i * 2]);
          buffers.uvs[j].push(faceUVs[j][i * 2 + 1]);
        });
      }
    }
  }

  addMorphTargets(parentGeo, parentGeoNode, morphTargets, preTransform) {
    if (morphTargets.length === 0) return;

    parentGeo.morphTargetsRelative = true;

    parentGeo.morphAttributes.position = [];
    // parentGeo.morphAttributes.normal = []; // not implemented

    const scope = this;
    morphTargets.forEach(function (morphTarget) {
      morphTarget.rawTargets.forEach(function (rawTarget) {
        const morphGeoNode = fbxTree.Objects.Geometry[rawTarget.geoID];

        if (morphGeoNode !== undefined) {
          scope.genMorphGeometry(
            parentGeo,
            parentGeoNode,
            morphGeoNode,
            preTransform,
            rawTarget.name
          );
        }
      });
    });
  }

  // a morph geometry node is similar to a standard  node, and the node is also contained
  // in FBXTree.Objects.Geometry, however it can only have attributes for position, normal
  // and a special attribute Index defining which vertices of the original geometry are affected
  // Normal and position attributes only have data for the vertices that are affected by the morph
  genMorphGeometry(parentGeo, parentGeoNode, morphGeoNode, preTransform, name) {
    const vertexIndices =
      parentGeoNode.PolygonVertexIndex !== undefined
        ? parentGeoNode.PolygonVertexIndex.a
        : [];

    const morphPositionsSparse =
      morphGeoNode.Vertices !== undefined ? morphGeoNode.Vertices.a : [];
    const indices =
      morphGeoNode.Indexes !== undefined ? morphGeoNode.Indexes.a : [];

    const length = parentGeo.attributes.position.count * 3;
    const morphPositions = new Float32Array(length);

    for (let i = 0; i < indices.length; i++) {
      const morphIndex = indices[i] * 3;

      morphPositions[morphIndex] = morphPositionsSparse[i * 3];
      morphPositions[morphIndex + 1] = morphPositionsSparse[i * 3 + 1];
      morphPositions[morphIndex + 2] = morphPositionsSparse[i * 3 + 2];
    }

    // TODO: add morph normal support
    const morphGeoInfo = {
      vertexIndices: vertexIndices,
      vertexPositions: morphPositions,
    };

    const morphBuffers = this.genBuffers(morphGeoInfo);

    const positionAttribute = new Float32BufferAttribute(
      morphBuffers.vertex,
      3
    );
    positionAttribute.name = name || morphGeoNode.attrName;

    positionAttribute.applyMatrix4(preTransform);

    parentGeo.morphAttributes.position.push(positionAttribute);
  }

  // Parse normal from FBXTree.Objects.Geometry.LayerElementNormal if it exists
  parseNormals(NormalNode) {
    const mappingType = NormalNode.MappingInformationType;
    const referenceType = NormalNode.ReferenceInformationType;
    const buffer = NormalNode.Normals.a;
    let indexBuffer = [];
    if (referenceType === "IndexToDirect") {
      if ("NormalIndex" in NormalNode) {
        indexBuffer = NormalNode.NormalIndex.a;
      } else if ("NormalsIndex" in NormalNode) {
        indexBuffer = NormalNode.NormalsIndex.a;
      }
    }

    return {
      dataSize: 3,
      buffer: buffer,
      indices: indexBuffer,
      mappingType: mappingType,
      referenceType: referenceType,
    };
  }

  // Parse UVs from FBXTree.Objects.Geometry.LayerElementUV if it exists
  parseUVs(UVNode) {
    const mappingType = UVNode.MappingInformationType;
    const referenceType = UVNode.ReferenceInformationType;
    const buffer = UVNode.UV.a;
    let indexBuffer = [];
    if (referenceType === "IndexToDirect") {
      indexBuffer = UVNode.UVIndex.a;
    }

    return {
      dataSize: 2,
      buffer: buffer,
      indices: indexBuffer,
      mappingType: mappingType,
      referenceType: referenceType,
    };
  }

  // Parse Vertex Colors from FBXTree.Objects.Geometry.LayerElementColor if it exists
  parseVertexColors(ColorNode) {
    const mappingType = ColorNode.MappingInformationType;
    const referenceType = ColorNode.ReferenceInformationType;
    const buffer = ColorNode.Colors.a;
    let indexBuffer = [];
    if (referenceType === "IndexToDirect") {
      indexBuffer = ColorNode.ColorIndex.a;
    }

    for (let i = 0, c = new Color(); i < buffer.length; i += 4) {
      c.fromArray(buffer, i).convertSRGBToLinear().toArray(buffer, i);
    }

    return {
      dataSize: 4,
      buffer: buffer,
      indices: indexBuffer,
      mappingType: mappingType,
      referenceType: referenceType,
    };
  }

  // Parse mapping and material data in FBXTree.Objects.Geometry.LayerElementMaterial if it exists
  parseMaterialIndices(MaterialNode) {
    const mappingType = MaterialNode.MappingInformationType;
    const referenceType = MaterialNode.ReferenceInformationType;

    if (mappingType === "NoMappingInformation") {
      return {
        dataSize: 1,
        buffer: [0],
        indices: [0],
        mappingType: "AllSame",
        referenceType: referenceType,
      };
    }

    const materialIndexBuffer = MaterialNode.Materials.a;

    // Since materials are stored as indices, there's a bit of a mismatch between FBX and what
    // we expect.So we create an intermediate buffer that points to the index in the buffer,
    // for conforming with the other functions we've written for other data.
    const materialIndices = [];

    for (let i = 0; i < materialIndexBuffer.length; ++i) {
      materialIndices.push(i);
    }

    return {
      dataSize: 1,
      buffer: materialIndexBuffer,
      indices: materialIndices,
      mappingType: mappingType,
      referenceType: referenceType,
    };
  }

  // Generate a NurbGeometry from a node in FBXTree.Objects.Geometry
  parseNurbsGeometry(geoNode) {
    const order = parseInt(geoNode.Order);

    if (isNaN(order)) {
      console.error(
        "THREE.FBXLoader: Invalid Order %s given for geometry ID: %s",
        geoNode.Order,
        geoNode.id
      );
      return new BufferGeometry();
    }

    const degree = order - 1;

    const knots = geoNode.KnotVector.a;
    const controlPoints = [];
    const pointsValues = geoNode.Points.a;

    for (let i = 0, l = pointsValues.length; i < l; i += 4) {
      controlPoints.push(new Vector4().fromArray(pointsValues, i));
    }

    let startKnot, endKnot;

    if (geoNode.Form === "Closed") {
      controlPoints.push(controlPoints[0]);
    } else if (geoNode.Form === "Periodic") {
      startKnot = degree;
      endKnot = knots.length - 1 - startKnot;

      for (let i = 0; i < degree; ++i) {
        controlPoints.push(controlPoints[i]);
      }
    }

    const curve = new NURBSCurve(
      degree,
      knots,
      controlPoints,
      startKnot,
      endKnot
    );
    const points = curve.getPoints(controlPoints.length * 12);

    return new BufferGeometry().setFromPoints(points);
  }
}

// parse animation data from FBXTree
class AnimationParser {
  // take raw animation clips and turn them into three.js animation clips
  parse() {
    const animationClips = [];

    const rawClips = this.parseClips();

    if (rawClips !== undefined) {
      for (const key in rawClips) {
        const rawClip = rawClips[key];

        const clip = this.addClip(rawClip);

        animationClips.push(clip);
      }
    }

    return animationClips;
  }

  parseClips() {
    // since the actual transformation data is stored in FBXTree.Objects.AnimationCurve,
    // if this is undefined we can safely assume there are no animations
    if (fbxTree.Objects.AnimationCurve === undefined) return undefined;

    const curveNodesMap = this.parseAnimationCurveNodes();

    this.parseAnimationCurves(curveNodesMap);

    const layersMap = this.parseAnimationLayers(curveNodesMap);
    const rawClips = this.parseAnimStacks(layersMap);

    return rawClips;
  }

  // parse nodes in FBXTree.Objects.AnimationCurveNode
  // each AnimationCurveNode holds data for an animation transform for a model (e.g. left arm rotation )
  // and is referenced by an AnimationLayer
  parseAnimationCurveNodes() {
    const rawCurveNodes = fbxTree.Objects.AnimationCurveNode;

    const curveNodesMap = new Map();

    for (const nodeID in rawCurveNodes) {
      const rawCurveNode = rawCurveNodes[nodeID];

      if (rawCurveNode.attrName.match(/S|R|T|DeformPercent/) !== null) {
        const curveNode = {
          id: rawCurveNode.id,
          attr: rawCurveNode.attrName,
          curves: {},
        };

        curveNodesMap.set(curveNode.id, curveNode);
      }
    }

    return curveNodesMap;
  }

  // parse nodes in FBXTree.Objects.AnimationCurve and connect them up to
  // previously parsed AnimationCurveNodes. Each AnimationCurve holds data for a single animated
  // axis ( e.g. times and values of x rotation)
  parseAnimationCurves(curveNodesMap) {
    const rawCurves = fbxTree.Objects.AnimationCurve;

    // TODO: Many values are identical up to roundoff error, but won't be optimised
    // e.g. position times: [0, 0.4, 0. 8]
    // position values: [7.23538335023477e-7, 93.67518615722656, -0.9982695579528809, 7.23538335023477e-7, 93.67518615722656, -0.9982695579528809, 7.235384487103147e-7, 93.67520904541016, -0.9982695579528809]
    // clearly, this should be optimised to
    // times: [0], positions [7.23538335023477e-7, 93.67518615722656, -0.9982695579528809]
    // this shows up in nearly every FBX file, and generally time array is length > 100

    for (const nodeID in rawCurves) {
      const animationCurve = {
        id: rawCurves[nodeID].id,
        times: rawCurves[nodeID].KeyTime.a.map(convertFBXTimeToSeconds),
        values: rawCurves[nodeID].KeyValueFloat.a,
      };

      const relationships = connections.get(animationCurve.id);

      if (relationships !== undefined) {
        const animationCurveID = relationships.parents[0].ID;
        const animationCurveRelationship =
          relationships.parents[0].relationship;

        if (animationCurveRelationship.match(/X/)) {
          curveNodesMap.get(animationCurveID).curves["x"] = animationCurve;
        } else if (animationCurveRelationship.match(/Y/)) {
          curveNodesMap.get(animationCurveID).curves["y"] = animationCurve;
        } else if (animationCurveRelationship.match(/Z/)) {
          curveNodesMap.get(animationCurveID).curves["z"] = animationCurve;
        } else if (
          animationCurveRelationship.match(/DeformPercent/) &&
          curveNodesMap.has(animationCurveID)
        ) {
          curveNodesMap.get(animationCurveID).curves["morph"] = animationCurve;
        }
      }
    }
  }

  // parse nodes in FBXTree.Objects.AnimationLayer. Each layers holds references
  // to various AnimationCurveNodes and is referenced by an AnimationStack node
  // note: theoretically a stack can have multiple layers, however in practice there always seems to be one per stack
  parseAnimationLayers(curveNodesMap) {
    const rawLayers = fbxTree.Objects.AnimationLayer;

    const layersMap = new Map();

    for (const nodeID in rawLayers) {
      const layerCurveNodes = [];

      const connection = connections.get(parseInt(nodeID));

      if (connection !== undefined) {
        // all the animationCurveNodes used in the layer
        const children = connection.children;

        children.forEach(function (child, i) {
          if (curveNodesMap.has(child.ID)) {
            const curveNode = curveNodesMap.get(child.ID);

            // check that the curves are defined for at least one axis, otherwise ignore the curveNode
            if (
              curveNode.curves.x !== undefined ||
              curveNode.curves.y !== undefined ||
              curveNode.curves.z !== undefined
            ) {
              if (layerCurveNodes[i] === undefined) {
                const modelID = connections
                  .get(child.ID)
                  .parents.filter(function (parent) {
                    return parent.relationship !== undefined;
                  })[0].ID;

                if (modelID !== undefined) {
                  const rawModel = fbxTree.Objects.Model[modelID.toString()];

                  if (rawModel === undefined) {
                    console.warn(
                      "THREE.FBXLoader: Encountered a unused curve.",
                      child
                    );
                    return;
                  }

                  const node = {
                    modelName: rawModel.attrName
                      ? PropertyBinding.sanitizeNodeName(rawModel.attrName)
                      : "",
                    ID: rawModel.id,
                    initialPosition: [0, 0, 0],
                    initialRotation: [0, 0, 0],
                    initialScale: [1, 1, 1],
                  };

                  sceneGraph.traverse(function (child) {
                    if (child.ID === rawModel.id) {
                      node.transform = child.matrix;

                      if (child.userData.transformData)
                        node.eulerOrder =
                          child.userData.transformData.eulerOrder;
                    }
                  });

                  if (!node.transform) node.transform = new Matrix4();

                  // if the animated model is pre rotated, we'll have to apply the pre rotations to every
                  // animation value as well
                  if ("PreRotation" in rawModel)
                    node.preRotation = rawModel.PreRotation.value;
                  if ("PostRotation" in rawModel)
                    node.postRotation = rawModel.PostRotation.value;

                  layerCurveNodes[i] = node;
                }
              }

              if (layerCurveNodes[i])
                layerCurveNodes[i][curveNode.attr] = curveNode;
            } else if (curveNode.curves.morph !== undefined) {
              if (layerCurveNodes[i] === undefined) {
                const deformerID = connections
                  .get(child.ID)
                  .parents.filter(function (parent) {
                    return parent.relationship !== undefined;
                  })[0].ID;

                const morpherID = connections.get(deformerID).parents[0].ID;
                const geoID = connections.get(morpherID).parents[0].ID;

                // assuming geometry is not used in more than one model
                const modelID = connections.get(geoID).parents[0].ID;

                const rawModel = fbxTree.Objects.Model[modelID];

                const node = {
                  modelName: rawModel.attrName
                    ? PropertyBinding.sanitizeNodeName(rawModel.attrName)
                    : "",
                  morphName: fbxTree.Objects.Deformer[deformerID].attrName,
                };

                layerCurveNodes[i] = node;
              }

              layerCurveNodes[i][curveNode.attr] = curveNode;
            }
          }
        });

        layersMap.set(parseInt(nodeID), layerCurveNodes);
      }
    }

    return layersMap;
  }

  // parse nodes in FBXTree.Objects.AnimationStack. These are the top level node in the animation
  // hierarchy. Each Stack node will be used to create a AnimationClip
  parseAnimStacks(layersMap) {
    const rawStacks = fbxTree.Objects.AnimationStack;

    // connect the stacks (clips) up to the layers
    const rawClips = {};

    for (const nodeID in rawStacks) {
      const children = connections.get(parseInt(nodeID)).children;

      if (children.length > 1) {
        // it seems like stacks will always be associated with a single layer. But just in case there are files
        // where there are multiple layers per stack, we'll display a warning
        console.warn(
          "THREE.FBXLoader: Encountered an animation stack with multiple layers, this is currently not supported. Ignoring subsequent layers."
        );
      }

      const layer = layersMap.get(children[0].ID);

      rawClips[nodeID] = {
        name: rawStacks[nodeID].attrName,
        layer: layer,
      };
    }

    return rawClips;
  }

  addClip(rawClip) {
    let tracks = [];

    const scope = this;
    rawClip.layer.forEach(function (rawTracks) {
      tracks = tracks.concat(scope.generateTracks(rawTracks));
    });

    return new AnimationClip(rawClip.name, -1, tracks);
  }

  generateTracks(rawTracks) {
    const tracks = [];

    let initialPosition = new Vector3();
    let initialRotation = new Quaternion();
    let initialScale = new Vector3();

    if (rawTracks.transform)
      rawTracks.transform.decompose(
        initialPosition,
        initialRotation,
        initialScale
      );

    initialPosition = initialPosition.toArray();
    initialRotation = new Euler()
      .setFromQuaternion(initialRotation, rawTracks.eulerOrder)
      .toArray();
    initialScale = initialScale.toArray();

    if (
      rawTracks.T !== undefined &&
      Object.keys(rawTracks.T.curves).length > 0
    ) {
      const positionTrack = this.generateVectorTrack(
        rawTracks.modelName,
        rawTracks.T.curves,
        initialPosition,
        "position"
      );
      if (positionTrack !== undefined) tracks.push(positionTrack);
    }

    if (
      rawTracks.R !== undefined &&
      Object.keys(rawTracks.R.curves).length > 0
    ) {
      const rotationTrack = this.generateRotationTrack(
        rawTracks.modelName,
        rawTracks.R.curves,
        initialRotation,
        rawTracks.preRotation,
        rawTracks.postRotation,
        rawTracks.eulerOrder
      );
      if (rotationTrack !== undefined) tracks.push(rotationTrack);
    }

    if (
      rawTracks.S !== undefined &&
      Object.keys(rawTracks.S.curves).length > 0
    ) {
      const scaleTrack = this.generateVectorTrack(
        rawTracks.modelName,
        rawTracks.S.curves,
        initialScale,
        "scale"
      );
      if (scaleTrack !== undefined) tracks.push(scaleTrack);
    }

    if (rawTracks.DeformPercent !== undefined) {
      const morphTrack = this.generateMorphTrack(rawTracks);
      if (morphTrack !== undefined) tracks.push(morphTrack);
    }

    return tracks;
  }

  generateVectorTrack(modelName, curves, initialValue, type) {
    const times = this.getTimesForAllAxes(curves);
    const values = this.getKeyframeTrackValues(times, curves, initialValue);

    return new VectorKeyframeTrack(modelName + "." + type, times, values);
  }

  generateRotationTrack(
    modelName,
    curves,
    initialValue,
    preRotation,
    postRotation,
    eulerOrder
  ) {
    if (curves.x !== undefined) {
      this.interpolateRotations(curves.x);
      curves.x.values = curves.x.values.map(MathUtils.degToRad);
    }

    if (curves.y !== undefined) {
      this.interpolateRotations(curves.y);
      curves.y.values = curves.y.values.map(MathUtils.degToRad);
    }

    if (curves.z !== undefined) {
      this.interpolateRotations(curves.z);
      curves.z.values = curves.z.values.map(MathUtils.degToRad);
    }

    const times = this.getTimesForAllAxes(curves);
    const values = this.getKeyframeTrackValues(times, curves, initialValue);

    if (preRotation !== undefined) {
      preRotation = preRotation.map(MathUtils.degToRad);
      preRotation.push(eulerOrder);

      preRotation = new Euler().fromArray(preRotation);
      preRotation = new Quaternion().setFromEuler(preRotation);
    }

    if (postRotation !== undefined) {
      postRotation = postRotation.map(MathUtils.degToRad);
      postRotation.push(eulerOrder);

      postRotation = new Euler().fromArray(postRotation);
      postRotation = new Quaternion().setFromEuler(postRotation).invert();
    }

    const quaternion = new Quaternion();
    const euler = new Euler();

    const quaternionValues = [];

    for (let i = 0; i < values.length; i += 3) {
      euler.set(values[i], values[i + 1], values[i + 2], eulerOrder);

      quaternion.setFromEuler(euler);

      if (preRotation !== undefined) quaternion.premultiply(preRotation);
      if (postRotation !== undefined) quaternion.multiply(postRotation);

      quaternion.toArray(quaternionValues, (i / 3) * 4);
    }

    return new QuaternionKeyframeTrack(
      modelName + ".quaternion",
      times,
      quaternionValues
    );
  }

  generateMorphTrack(rawTracks) {
    const curves = rawTracks.DeformPercent.curves.morph;
    const values = curves.values.map(function (val) {
      return val / 100;
    });

    const morphNum = sceneGraph.getObjectByName(rawTracks.modelName)
      .morphTargetDictionary[rawTracks.morphName];

    return new NumberKeyframeTrack(
      rawTracks.modelName + ".morphTargetInfluences[" + morphNum + "]",
      curves.times,
      values
    );
  }

  // For all animated objects, times are defined separately for each axis
  // Here we'll combine the times into one sorted array without duplicates
  getTimesForAllAxes(curves) {
    let times = [];

    // first join together the times for each axis, if defined
    if (curves.x !== undefined) times = times.concat(curves.x.times);
    if (curves.y !== undefined) times = times.concat(curves.y.times);
    if (curves.z !== undefined) times = times.concat(curves.z.times);

    // then sort them
    times = times.sort(function (a, b) {
      return a - b;
    });

    // and remove duplicates
    if (times.length > 1) {
      let targetIndex = 1;
      let lastValue = times[0];
      for (let i = 1; i < times.length; i++) {
        const currentValue = times[i];
        if (currentValue !== lastValue) {
          times[targetIndex] = currentValue;
          lastValue = currentValue;
          targetIndex++;
        }
      }

      times = times.slice(0, targetIndex);
    }

    return times;
  }

  getKeyframeTrackValues(times, curves, initialValue) {
    const prevValue = initialValue;

    const values = [];

    let xIndex = -1;
    let yIndex = -1;
    let zIndex = -1;

    times.forEach(function (time) {
      if (curves.x) xIndex = curves.x.times.indexOf(time);
      if (curves.y) yIndex = curves.y.times.indexOf(time);
      if (curves.z) zIndex = curves.z.times.indexOf(time);

      // if there is an x value defined for this frame, use that
      if (xIndex !== -1) {
        const xValue = curves.x.values[xIndex];
        values.push(xValue);
        prevValue[0] = xValue;
      } else {
        // otherwise use the x value from the previous frame
        values.push(prevValue[0]);
      }

      if (yIndex !== -1) {
        const yValue = curves.y.values[yIndex];
        values.push(yValue);
        prevValue[1] = yValue;
      } else {
        values.push(prevValue[1]);
      }

      if (zIndex !== -1) {
        const zValue = curves.z.values[zIndex];
        values.push(zValue);
        prevValue[2] = zValue;
      } else {
        values.push(prevValue[2]);
      }
    });

    return values;
  }

  // Rotations are defined as Euler angles which can have values  of any size
  // These will be converted to quaternions which don't support values greater than
  // PI, so we'll interpolate large rotations
  interpolateRotations(curve) {
    for (let i = 1; i < curve.values.length; i++) {
      const initialValue = curve.values[i - 1];
      const valuesSpan = curve.values[i] - initialValue;

      const absoluteSpan = Math.abs(valuesSpan);

      if (absoluteSpan >= 180) {
        const numSubIntervals = absoluteSpan / 180;

        const step = valuesSpan / numSubIntervals;
        let nextValue = initialValue + step;

        const initialTime = curve.times[i - 1];
        const timeSpan = curve.times[i] - initialTime;
        const interval = timeSpan / numSubIntervals;
        let nextTime = initialTime + interval;

        const interpolatedTimes = [];
        const interpolatedValues = [];

        while (nextTime < curve.times[i]) {
          interpolatedTimes.push(nextTime);
          nextTime += interval;

          interpolatedValues.push(nextValue);
          nextValue += step;
        }

        curve.times = inject(curve.times, i, interpolatedTimes);
        curve.values = inject(curve.values, i, interpolatedValues);
      }
    }
  }
}

// parse an FBX file in ASCII format
class TextParser {
  getPrevNode() {
    return this.nodeStack[this.currentIndent - 2];
  }

  getCurrentNode() {
    return this.nodeStack[this.currentIndent - 1];
  }

  getCurrentProp() {
    return this.currentProp;
  }

  pushStack(node) {
    this.nodeStack.push(node);
    this.currentIndent += 1;
  }

  popStack() {
    this.nodeStack.pop();
    this.currentIndent -= 1;
  }

  setCurrentProp(val, name) {
    this.currentProp = val;
    this.currentPropName = name;
  }

  parse(text) {
    this.currentIndent = 0;

    this.allNodes = new FBXTree();
    this.nodeStack = [];
    this.currentProp = [];
    this.currentPropName = "";

    const scope = this;

    const split = text.split(/[\r\n]+/);

    split.forEach(function (line, i) {
      const matchComment = line.match(/^[\s\t]*;/);
      const matchEmpty = line.match(/^[\s\t]*$/);

      if (matchComment || matchEmpty) return;

      const matchBeginning = line.match(
        "^\\t{" + scope.currentIndent + "}(\\w+):(.*){",
        ""
      );
      const matchProperty = line.match(
        "^\\t{" + scope.currentIndent + "}(\\w+):[\\s\\t\\r\\n](.*)"
      );
      const matchEnd = line.match("^\\t{" + (scope.currentIndent - 1) + "}}");

      if (matchBeginning) {
        scope.parseNodeBegin(line, matchBeginning);
      } else if (matchProperty) {
        scope.parseNodeProperty(line, matchProperty, split[++i]);
      } else if (matchEnd) {
        scope.popStack();
      } else if (line.match(/^[^\s\t}]/)) {
        // large arrays are split over multiple lines terminated with a ',' character
        // if this is encountered the line needs to be joined to the previous line
        scope.parseNodePropertyContinued(line);
      }
    });

    return this.allNodes;
  }

  parseNodeBegin(line, property) {
    const nodeName = property[1].trim().replace(/^"/, "").replace(/"$/, "");

    const nodeAttrs = property[2].split(",").map(function (attr) {
      return attr.trim().replace(/^"/, "").replace(/"$/, "");
    });

    const node = { name: nodeName };
    const attrs = this.parseNodeAttr(nodeAttrs);

    const currentNode = this.getCurrentNode();

    // a top node
    if (this.currentIndent === 0) {
      this.allNodes.add(nodeName, node);
    } else {
      // a subnode

      // if the subnode already exists, append it
      if (nodeName in currentNode) {
        // special case Pose needs PoseNodes as an array
        if (nodeName === "PoseNode") {
          currentNode.PoseNode.push(node);
        } else if (currentNode[nodeName].id !== undefined) {
          currentNode[nodeName] = {};
          currentNode[nodeName][currentNode[nodeName].id] =
            currentNode[nodeName];
        }

        if (attrs.id !== "") currentNode[nodeName][attrs.id] = node;
      } else if (typeof attrs.id === "number") {
        currentNode[nodeName] = {};
        currentNode[nodeName][attrs.id] = node;
      } else if (nodeName !== "Properties70") {
        if (nodeName === "PoseNode") currentNode[nodeName] = [node];
        else currentNode[nodeName] = node;
      }
    }

    if (typeof attrs.id === "number") node.id = attrs.id;
    if (attrs.name !== "") node.attrName = attrs.name;
    if (attrs.type !== "") node.attrType = attrs.type;

    this.pushStack(node);
  }

  parseNodeAttr(attrs) {
    let id = attrs[0];

    if (attrs[0] !== "") {
      id = parseInt(attrs[0]);

      if (isNaN(id)) {
        id = attrs[0];
      }
    }

    let name = "",
      type = "";

    if (attrs.length > 1) {
      name = attrs[1].replace(/^(\w+)::/, "");
      type = attrs[2];
    }

    return { id: id, name: name, type: type };
  }

  parseNodeProperty(line, property, contentLine) {
    let propName = property[1].replace(/^"/, "").replace(/"$/, "").trim();
    let propValue = property[2].replace(/^"/, "").replace(/"$/, "").trim();

    // for special case: base64 image data follows "Content: ," line
    //	Content: ,
    //	 "/9j/4RDaRXhpZgAATU0A..."
    if (propName === "Content" && propValue === ",") {
      propValue = contentLine.replace(/"/g, "").replace(/,$/, "").trim();
    }

    const currentNode = this.getCurrentNode();
    const parentName = currentNode.name;

    if (parentName === "Properties70") {
      this.parseNodeSpecialProperty(line, propName, propValue);
      return;
    }

    // Connections
    if (propName === "C") {
      const connProps = propValue.split(",").slice(1);
      const from = parseInt(connProps[0]);
      const to = parseInt(connProps[1]);

      let rest = propValue.split(",").slice(3);

      rest = rest.map(function (elem) {
        return elem.trim().replace(/^"/, "");
      });

      propName = "connections";
      propValue = [from, to];
      append(propValue, rest);

      if (currentNode[propName] === undefined) {
        currentNode[propName] = [];
      }
    }

    // Node
    if (propName === "Node") currentNode.id = propValue;

    // connections
    if (propName in currentNode && Array.isArray(currentNode[propName])) {
      currentNode[propName].push(propValue);
    } else {
      if (propName !== "a") currentNode[propName] = propValue;
      else currentNode.a = propValue;
    }

    this.setCurrentProp(currentNode, propName);

    // convert string to array, unless it ends in ',' in which case more will be added to it
    if (propName === "a" && propValue.slice(-1) !== ",") {
      currentNode.a = parseNumberArray(propValue);
    }
  }

  parseNodePropertyContinued(line) {
    const currentNode = this.getCurrentNode();

    currentNode.a += line;

    // if the line doesn't end in ',' we have reached the end of the property value
    // so convert the string to an array
    if (line.slice(-1) !== ",") {
      currentNode.a = parseNumberArray(currentNode.a);
    }
  }

  // parse "Property70"
  parseNodeSpecialProperty(line, propName, propValue) {
    // split this
    // P: "Lcl Scaling", "Lcl Scaling", "", "A",1,1,1
    // into array like below
    // ["Lcl Scaling", "Lcl Scaling", "", "A", "1,1,1" ]
    const props = propValue.split('",').map(function (prop) {
      return prop.trim().replace(/^\"/, "").replace(/\s/, "_");
    });

    const innerPropName = props[0];
    const innerPropType1 = props[1];
    const innerPropType2 = props[2];
    const innerPropFlag = props[3];
    let innerPropValue = props[4];

    // cast values where needed, otherwise leave as strings
    switch (innerPropType1) {
      case "int":
      case "enum":
      case "bool":
      case "ULongLong":
      case "double":
      case "Number":
      case "FieldOfView":
        innerPropValue = parseFloat(innerPropValue);
        break;

      case "Color":
      case "ColorRGB":
      case "Vector3D":
      case "Lcl_Translation":
      case "Lcl_Rotation":
      case "Lcl_Scaling":
        innerPropValue = parseNumberArray(innerPropValue);
        break;
    }

    // CAUTION: these props must append to parent's parent
    this.getPrevNode()[innerPropName] = {
      type: innerPropType1,
      type2: innerPropType2,
      flag: innerPropFlag,
      value: innerPropValue,
    };

    this.setCurrentProp(this.getPrevNode(), innerPropName);
  }
}

// Parse an FBX file in Binary format
class BinaryParser {
  parse(buffer) {
    const reader = new BinaryReader(buffer);
    reader.skip(23); // skip magic 23 bytes

    const version = reader.getUint32();

    if (version < 6400) {
      throw new Error(
        "THREE.FBXLoader: FBX version not supported, FileVersion: " + version
      );
    }

    const allNodes = new FBXTree();

    while (!this.endOfContent(reader)) {
      const node = this.parseNode(reader, version);
      if (node !== null) allNodes.add(node.name, node);
    }

    return allNodes;
  }

  // Check if reader has reached the end of content.
  endOfContent(reader) {
    // footer size: 160bytes + 16-byte alignment padding
    // - 16bytes: magic
    // - padding til 16-byte alignment (at least 1byte?)
    //	(seems like some exporters embed fixed 15 or 16bytes?)
    // - 4bytes: magic
    // - 4bytes: version
    // - 120bytes: zero
    // - 16bytes: magic
    if (reader.size() % 16 === 0) {
      return ((reader.getOffset() + 160 + 16) & ~0xf) >= reader.size();
    } else {
      return reader.getOffset() + 160 + 16 >= reader.size();
    }
  }

  // recursively parse nodes until the end of the file is reached
  parseNode(reader, version) {
    const node = {};

    // The first three data sizes depends on version.
    const endOffset = version >= 7500 ? reader.getUint64() : reader.getUint32();
    const numProperties =
      version >= 7500 ? reader.getUint64() : reader.getUint32();

    version >= 7500 ? reader.getUint64() : reader.getUint32(); // the returned propertyListLen is not used

    const nameLen = reader.getUint8();
    const name = reader.getString(nameLen);

    // Regards this node as NULL-record if endOffset is zero
    if (endOffset === 0) return null;

    const propertyList = [];

    for (let i = 0; i < numProperties; i++) {
      propertyList.push(this.parseProperty(reader));
    }

    // Regards the first three elements in propertyList as id, attrName, and attrType
    const id = propertyList.length > 0 ? propertyList[0] : "";
    const attrName = propertyList.length > 1 ? propertyList[1] : "";
    const attrType = propertyList.length > 2 ? propertyList[2] : "";

    // check if this node represents just a single property
    // like (name, 0) set or (name2, [0, 1, 2]) set of {name: 0, name2: [0, 1, 2]}
    node.singleProperty =
      numProperties === 1 && reader.getOffset() === endOffset ? true : false;

    while (endOffset > reader.getOffset()) {
      const subNode = this.parseNode(reader, version);

      if (subNode !== null) this.parseSubNode(name, node, subNode);
    }

    node.propertyList = propertyList; // raw property list used by parent

    if (typeof id === "number") node.id = id;
    if (attrName !== "") node.attrName = attrName;
    if (attrType !== "") node.attrType = attrType;
    if (name !== "") node.name = name;

    return node;
  }

  parseSubNode(name, node, subNode) {
    // special case: child node is single property
    if (subNode.singleProperty === true) {
      const value = subNode.propertyList[0];

      if (Array.isArray(value)) {
        node[subNode.name] = subNode;

        subNode.a = value;
      } else {
        node[subNode.name] = value;
      }
    } else if (name === "Connections" && subNode.name === "C") {
      const array = [];

      subNode.propertyList.forEach(function (property, i) {
        // first Connection is FBX type (OO, OP, etc.). We'll discard these
        if (i !== 0) array.push(property);
      });

      if (node.connections === undefined) {
        node.connections = [];
      }

      node.connections.push(array);
    } else if (subNode.name === "Properties70") {
      const keys = Object.keys(subNode);

      keys.forEach(function (key) {
        node[key] = subNode[key];
      });
    } else if (name === "Properties70" && subNode.name === "P") {
      let innerPropName = subNode.propertyList[0];
      let innerPropType1 = subNode.propertyList[1];
      const innerPropType2 = subNode.propertyList[2];
      const innerPropFlag = subNode.propertyList[3];
      let innerPropValue;

      if (innerPropName.indexOf("Lcl ") === 0)
        innerPropName = innerPropName.replace("Lcl ", "Lcl_");
      if (innerPropType1.indexOf("Lcl ") === 0)
        innerPropType1 = innerPropType1.replace("Lcl ", "Lcl_");

      if (
        innerPropType1 === "Color" ||
        innerPropType1 === "ColorRGB" ||
        innerPropType1 === "Vector" ||
        innerPropType1 === "Vector3D" ||
        innerPropType1.indexOf("Lcl_") === 0
      ) {
        innerPropValue = [
          subNode.propertyList[4],
          subNode.propertyList[5],
          subNode.propertyList[6],
        ];
      } else {
        innerPropValue = subNode.propertyList[4];
      }

      // this will be copied to parent, see above
      node[innerPropName] = {
        type: innerPropType1,
        type2: innerPropType2,
        flag: innerPropFlag,
        value: innerPropValue,
      };
    } else if (node[subNode.name] === undefined) {
      if (typeof subNode.id === "number") {
        node[subNode.name] = {};
        node[subNode.name][subNode.id] = subNode;
      } else {
        node[subNode.name] = subNode;
      }
    } else {
      if (subNode.name === "PoseNode") {
        if (!Array.isArray(node[subNode.name])) {
          node[subNode.name] = [node[subNode.name]];
        }

        node[subNode.name].push(subNode);
      } else if (node[subNode.name][subNode.id] === undefined) {
        node[subNode.name][subNode.id] = subNode;
      }
    }
  }

  parseProperty(reader) {
    const type = reader.getString(1);
    let length;

    switch (type) {
      case "C":
        return reader.getBoolean();

      case "D":
        return reader.getFloat64();

      case "F":
        return reader.getFloat32();

      case "I":
        return reader.getInt32();

      case "L":
        return reader.getInt64();

      case "R":
        length = reader.getUint32();
        return reader.getArrayBuffer(length);

      case "S":
        length = reader.getUint32();
        return reader.getString(length);

      case "Y":
        return reader.getInt16();

      case "b":
      case "c":
      case "d":
      case "f":
      case "i":
      case "l":
        const arrayLength = reader.getUint32();
        const encoding = reader.getUint32(); // 0: non-compressed, 1: compressed
        const compressedLength = reader.getUint32();

        if (encoding === 0) {
          switch (type) {
            case "b":
            case "c":
              return reader.getBooleanArray(arrayLength);

            case "d":
              return reader.getFloat64Array(arrayLength);

            case "f":
              return reader.getFloat32Array(arrayLength);

            case "i":
              return reader.getInt32Array(arrayLength);

            case "l":
              return reader.getInt64Array(arrayLength);
          }
        }

        const data = fflate.unzlibSync(
          new Uint8Array(reader.getArrayBuffer(compressedLength))
        );
        const reader2 = new BinaryReader(data.buffer);

        switch (type) {
          case "b":
          case "c":
            return reader2.getBooleanArray(arrayLength);

          case "d":
            return reader2.getFloat64Array(arrayLength);

          case "f":
            return reader2.getFloat32Array(arrayLength);

          case "i":
            return reader2.getInt32Array(arrayLength);

          case "l":
            return reader2.getInt64Array(arrayLength);
        }

        break; // cannot happen but is required by the DeepScan

      default:
        throw new Error("THREE.FBXLoader: Unknown property type " + type);
    }
  }
}

class BinaryReader {
  constructor(buffer, littleEndian) {
    this.dv = new DataView(buffer);
    this.offset = 0;
    this.littleEndian = littleEndian !== undefined ? littleEndian : true;
    this._textDecoder = new TextDecoder();
  }

  getOffset() {
    return this.offset;
  }

  size() {
    return this.dv.buffer.byteLength;
  }

  skip(length) {
    this.offset += length;
  }

  // seems like true/false representation depends on exporter.
  // true: 1 or 'Y'(=0x59), false: 0 or 'T'(=0x54)
  // then sees LSB.
  getBoolean() {
    return (this.getUint8() & 1) === 1;
  }

  getBooleanArray(size) {
    const a = [];

    for (let i = 0; i < size; i++) {
      a.push(this.getBoolean());
    }

    return a;
  }

  getUint8() {
    const value = this.dv.getUint8(this.offset);
    this.offset += 1;
    return value;
  }

  getInt16() {
    const value = this.dv.getInt16(this.offset, this.littleEndian);
    this.offset += 2;
    return value;
  }

  getInt32() {
    const value = this.dv.getInt32(this.offset, this.littleEndian);
    this.offset += 4;
    return value;
  }

  getInt32Array(size) {
    const a = [];

    for (let i = 0; i < size; i++) {
      a.push(this.getInt32());
    }

    return a;
  }

  getUint32() {
    const value = this.dv.getUint32(this.offset, this.littleEndian);
    this.offset += 4;
    return value;
  }

  // JavaScript doesn't support 64-bit integer so calculate this here
  // 1 << 32 will return 1 so using multiply operation instead here.
  // There's a possibility that this method returns wrong value if the value
  // is out of the range between Number.MAX_SAFE_INTEGER and Number.MIN_SAFE_INTEGER.
  // TODO: safely handle 64-bit integer
  getInt64() {
    let low, high;

    if (this.littleEndian) {
      low = this.getUint32();
      high = this.getUint32();
    } else {
      high = this.getUint32();
      low = this.getUint32();
    }

    // calculate negative value
    if (high & 0x80000000) {
      high = ~high & 0xffffffff;
      low = ~low & 0xffffffff;

      if (low === 0xffffffff) high = (high + 1) & 0xffffffff;

      low = (low + 1) & 0xffffffff;

      return -(high * 0x100000000 + low);
    }

    return high * 0x100000000 + low;
  }

  getInt64Array(size) {
    const a = [];

    for (let i = 0; i < size; i++) {
      a.push(this.getInt64());
    }

    return a;
  }

  // Note: see getInt64() comment
  getUint64() {
    let low, high;

    if (this.littleEndian) {
      low = this.getUint32();
      high = this.getUint32();
    } else {
      high = this.getUint32();
      low = this.getUint32();
    }

    return high * 0x100000000 + low;
  }

  getFloat32() {
    const value = this.dv.getFloat32(this.offset, this.littleEndian);
    this.offset += 4;
    return value;
  }

  getFloat32Array(size) {
    const a = [];

    for (let i = 0; i < size; i++) {
      a.push(this.getFloat32());
    }

    return a;
  }

  getFloat64() {
    const value = this.dv.getFloat64(this.offset, this.littleEndian);
    this.offset += 8;
    return value;
  }

  getFloat64Array(size) {
    const a = [];

    for (let i = 0; i < size; i++) {
      a.push(this.getFloat64());
    }

    return a;
  }

  getArrayBuffer(size) {
    const value = this.dv.buffer.slice(this.offset, this.offset + size);
    this.offset += size;
    return value;
  }

  getString(size) {
    const start = this.offset;
    let a = new Uint8Array(this.dv.buffer, start, size);

    this.skip(size);

    const nullByte = a.indexOf(0);
    if (nullByte >= 0) a = new Uint8Array(this.dv.buffer, start, nullByte);

    return this._textDecoder.decode(a);
  }
}

// FBXTree holds a representation of the FBX data, returned by the TextParser ( FBX ASCII format)
// and BinaryParser( FBX Binary format)
class FBXTree {
  add(key, val) {
    this[key] = val;
  }
}

// ************** UTILITY FUNCTIONS **************

function isFbxFormatBinary(buffer) {
  const CORRECT = "Kaydara\u0020FBX\u0020Binary\u0020\u0020\0";

  return (
    buffer.byteLength >= CORRECT.length &&
    CORRECT === convertArrayBufferToString(buffer, 0, CORRECT.length)
  );
}

function isFbxFormatASCII(text) {
  const CORRECT = [
    "K",
    "a",
    "y",
    "d",
    "a",
    "r",
    "a",
    "\\",
    "F",
    "B",
    "X",
    "\\",
    "B",
    "i",
    "n",
    "a",
    "r",
    "y",
    "\\",
    "\\",
  ];

  let cursor = 0;

  function read(offset) {
    const result = text[offset - 1];
    text = text.slice(cursor + offset);
    cursor++;
    return result;
  }

  for (let i = 0; i < CORRECT.length; ++i) {
    const num = read(1);
    if (num === CORRECT[i]) {
      return false;
    }
  }

  return true;
}

function getFbxVersion(text) {
  const versionRegExp = /FBXVersion: (\d+)/;
  const match = text.match(versionRegExp);

  if (match) {
    const version = parseInt(match[1]);
    return version;
  }

  throw new Error(
    "THREE.FBXLoader: Cannot find the version number for the file given."
  );
}

// Converts FBX ticks into real time seconds.
function convertFBXTimeToSeconds(time) {
  return time / 46186158000;
}

const dataArray = [];

// extracts the data from the correct position in the FBX array based on indexing type
function getData(polygonVertexIndex, polygonIndex, vertexIndex, infoObject) {
  let index;

  switch (infoObject.mappingType) {
    case "ByPolygonVertex":
      index = polygonVertexIndex;
      break;
    case "ByPolygon":
      index = polygonIndex;
      break;
    case "ByVertice":
      index = vertexIndex;
      break;
    case "AllSame":
      index = infoObject.indices[0];
      break;
    default:
      console.warn(
        "THREE.FBXLoader: unknown attribute mapping type " +
          infoObject.mappingType
      );
  }

  if (infoObject.referenceType === "IndexToDirect")
    index = infoObject.indices[index];

  const from = index * infoObject.dataSize;
  const to = from + infoObject.dataSize;

  return slice(dataArray, infoObject.buffer, from, to);
}

const tempEuler = new Euler();
const tempVec = new Vector3();

// generate transformation from FBX transform data
// ref: https://help.autodesk.com/view/FBX/2017/ENU/?guid=__files_GUID_10CDD63C_79C1_4F2D_BB28_AD2BE65A02ED_htm
// ref: http://docs.autodesk.com/FBX/2014/ENU/FBX-SDK-Documentation/index.html?url=cpp_ref/_transformations_2main_8cxx-example.html,topicNumber=cpp_ref__transformations_2main_8cxx_example_htmlfc10a1e1-b18d-4e72-9dc0-70d0f1959f5e
function generateTransform(transformData) {
  const lTranslationM = new Matrix4();
  const lPreRotationM = new Matrix4();
  const lRotationM = new Matrix4();
  const lPostRotationM = new Matrix4();

  const lScalingM = new Matrix4();
  const lScalingPivotM = new Matrix4();
  const lScalingOffsetM = new Matrix4();
  const lRotationOffsetM = new Matrix4();
  const lRotationPivotM = new Matrix4();

  const lParentGX = new Matrix4();
  const lParentLX = new Matrix4();
  const lGlobalT = new Matrix4();

  const inheritType = transformData.inheritType ? transformData.inheritType : 0;

  if (transformData.translation)
    lTranslationM.setPosition(tempVec.fromArray(transformData.translation));

  if (transformData.preRotation) {
    const array = transformData.preRotation.map(MathUtils.degToRad);
    array.push(transformData.eulerOrder || Euler.DEFAULT_ORDER);
    lPreRotationM.makeRotationFromEuler(tempEuler.fromArray(array));
  }

  if (transformData.rotation) {
    const array = transformData.rotation.map(MathUtils.degToRad);
    array.push(transformData.eulerOrder || Euler.DEFAULT_ORDER);
    lRotationM.makeRotationFromEuler(tempEuler.fromArray(array));
  }

  if (transformData.postRotation) {
    const array = transformData.postRotation.map(MathUtils.degToRad);
    array.push(transformData.eulerOrder || Euler.DEFAULT_ORDER);
    lPostRotationM.makeRotationFromEuler(tempEuler.fromArray(array));
    lPostRotationM.invert();
  }

  if (transformData.scale)
    lScalingM.scale(tempVec.fromArray(transformData.scale));

  // Pivots and offsets
  if (transformData.scalingOffset)
    lScalingOffsetM.setPosition(tempVec.fromArray(transformData.scalingOffset));
  if (transformData.scalingPivot)
    lScalingPivotM.setPosition(tempVec.fromArray(transformData.scalingPivot));
  if (transformData.rotationOffset)
    lRotationOffsetM.setPosition(
      tempVec.fromArray(transformData.rotationOffset)
    );
  if (transformData.rotationPivot)
    lRotationPivotM.setPosition(tempVec.fromArray(transformData.rotationPivot));

  // parent transform
  if (transformData.parentMatrixWorld) {
    lParentLX.copy(transformData.parentMatrix);
    lParentGX.copy(transformData.parentMatrixWorld);
  }

  const lLRM = lPreRotationM
    .clone()
    .multiply(lRotationM)
    .multiply(lPostRotationM);
  // Global Rotation
  const lParentGRM = new Matrix4();
  lParentGRM.extractRotation(lParentGX);

  // Global Shear*Scaling
  const lParentTM = new Matrix4();
  lParentTM.copyPosition(lParentGX);

  const lParentGRSM = lParentTM.clone().invert().multiply(lParentGX);
  const lParentGSM = lParentGRM.clone().invert().multiply(lParentGRSM);
  const lLSM = lScalingM;

  const lGlobalRS = new Matrix4();

  if (inheritType === 0) {
    lGlobalRS
      .copy(lParentGRM)
      .multiply(lLRM)
      .multiply(lParentGSM)
      .multiply(lLSM);
  } else if (inheritType === 1) {
    lGlobalRS
      .copy(lParentGRM)
      .multiply(lParentGSM)
      .multiply(lLRM)
      .multiply(lLSM);
  } else {
    const lParentLSM = new Matrix4().scale(
      new Vector3().setFromMatrixScale(lParentLX)
    );
    const lParentLSM_inv = lParentLSM.clone().invert();
    const lParentGSM_noLocal = lParentGSM.clone().multiply(lParentLSM_inv);

    lGlobalRS
      .copy(lParentGRM)
      .multiply(lLRM)
      .multiply(lParentGSM_noLocal)
      .multiply(lLSM);
  }

  const lRotationPivotM_inv = lRotationPivotM.clone().invert();
  const lScalingPivotM_inv = lScalingPivotM.clone().invert();
  // Calculate the local transform matrix
  let lTransform = lTranslationM
    .clone()
    .multiply(lRotationOffsetM)
    .multiply(lRotationPivotM)
    .multiply(lPreRotationM)
    .multiply(lRotationM)
    .multiply(lPostRotationM)
    .multiply(lRotationPivotM_inv)
    .multiply(lScalingOffsetM)
    .multiply(lScalingPivotM)
    .multiply(lScalingM)
    .multiply(lScalingPivotM_inv);

  const lLocalTWithAllPivotAndOffsetInfo = new Matrix4().copyPosition(
    lTransform
  );

  const lGlobalTranslation = lParentGX
    .clone()
    .multiply(lLocalTWithAllPivotAndOffsetInfo);
  lGlobalT.copyPosition(lGlobalTranslation);

  lTransform = lGlobalT.clone().multiply(lGlobalRS);

  // from global to local
  lTransform.premultiply(lParentGX.invert());

  return lTransform;
}

// Returns the three.js intrinsic Euler order corresponding to FBX extrinsic Euler order
// ref: http://help.autodesk.com/view/FBX/2017/ENU/?guid=__cpp_ref_class_fbx_euler_html
function getEulerOrder(order) {
  order = order || 0;

  const enums = [
    "ZYX", // -> XYZ extrinsic
    "YZX", // -> XZY extrinsic
    "XZY", // -> YZX extrinsic
    "ZXY", // -> YXZ extrinsic
    "YXZ", // -> ZXY extrinsic
    "XYZ", // -> ZYX extrinsic
    //'SphericXYZ', // not possible to support
  ];

  if (order === 6) {
    console.warn(
      "THREE.FBXLoader: unsupported Euler Order: Spherical XYZ. Animations and rotations may be incorrect."
    );
    return enums[0];
  }

  return enums[order];
}

// Parses comma separated list of numbers and returns them an array.
// Used internally by the TextParser
function parseNumberArray(value) {
  const array = value.split(",").map(function (val) {
    return parseFloat(val);
  });

  return array;
}

function convertArrayBufferToString(buffer, from, to) {
  if (from === undefined) from = 0;
  if (to === undefined) to = buffer.byteLength;

  return new TextDecoder().decode(new Uint8Array(buffer, from, to));
}

function append(a, b) {
  for (let i = 0, j = a.length, l = b.length; i < l; i++, j++) {
    a[j] = b[i];
  }
}

function slice(a, b, from, to) {
  for (let i = from, j = 0; i < to; i++, j++) {
    a[j] = b[i];
  }

  return a;
}

// inject array a2 into array a1 at index
function inject(a1, index, a2) {
  return a1.slice(0, index).concat(a2).concat(a1.slice(index));
}

export { FBXLoader };