import path from "path";
import fs from "fs";
import { NodeIO } from "@gltf-transform/core";
import { dedup, prune } from "@gltf-transform/functions";
import { KHRONOS_EXTENSIONS } from "@gltf-transform/extensions";

const baseDir = "C:/glTF-Sample-Assets/Models/";

function ensureDirectoryExists(fileName: string) {
  const directory = path.dirname(fileName);
  if (!fs.existsSync(directory)) {
    fs.mkdirSync(directory, { recursive: true });
  }
}

async function runOptimize(modelName: string) {
  const inputDir = baseDir + modelName + "/glTF/";
  const outputDir = baseDir + modelName + "/glTF-Optimized/";

  const inputFileName = inputDir + modelName + ".gltf";
  const outputFileName = outputDir + modelName + ".gltf";

  const io = new NodeIO().registerExtensions(KHRONOS_EXTENSIONS);
  const document = await io.read(inputFileName);
  await document.transform(dedup());
  await document.transform(prune());
  const meshes = document.getRoot().listMeshes();
  for (const mesh of meshes) {
    const primitives = mesh.listPrimitives();
    for (const primitive of primitives) {
      if (primitive.getMaterial()?.getBaseColorTexture() === null) {
        primitive.setAttribute("TEXCOORD_0", null);
      }
    }
  }
  const jsonDocument = await io.writeJSON(document);

  ensureDirectoryExists(outputFileName);
  fs.writeFileSync(outputFileName, JSON.stringify(jsonDocument.json, null, 2));
  for (const uri of Object.keys(jsonDocument.resources)) {
    const resource = jsonDocument.resources[uri];
    const resourceFileName = path.join(outputDir, uri);
    ensureDirectoryExists(resourceFileName);
    fs.writeFileSync(resourceFileName, resource);
  }
}

async function run() {
  await runOptimize("IridescenceDielectricSpheres");
  await runOptimize("IridescenceMetallicSpheres");
}

run();