import { Mesh } from "../src/Mesh";
import { Scene } from "../src/Scene";
import type { PBRMaterial } from "../src/materials/PBRMaterial";
import type { YawnCore } from "./core-mock";

export const triangle = {
  positions: [-1, -1, 0, 1, -1, 0, 0, 1, 0],
  normals: [0, 0, 1, 0, 0, 1, 0, 0, 1],
  tangents: [1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1],
  uvs: [0, 0, 1, 0, 0.5, 1],
  uvs2: [0.1, 0.1, 0.9, 0.1, 0.5, 0.9],
  colors: [1, 0, 0, 1, 0, 1, 0, 1, 0, 0, 1, 1],
  indices: [0, 1, 2],
};

export async function createScene(
  options: ConstructorParameters<typeof Scene>[1] = {},
) {
  const scene = new Scene({} as HTMLCanvasElement, options);
  await scene.ready;
  return scene;
}

export function testCore(scene: Scene) {
  return scene.core as unknown as YawnCore;
}

export function latestGraph(scene: Scene): any {
  return testCore(scene).graphs.at(-1);
}

export function renderPipeline(graph: any, id: string) {
  return graph.pipelines.render.find((pipeline: any) => pipeline.id === id);
}

export function pbrPipelines(graph: any) {
  return graph.pipelines.render.filter((pipeline: any) =>
    pipeline.id.startsWith("forward-pbr-"),
  );
}

export function forwardPasses(graph: any) {
  return graph.passes.filter(
    (pass: any) =>
      pass.type === "render" && pass.pipeline.startsWith("forward-"),
  );
}

export function detailedMesh(
  scene: Scene,
  material: PBRMaterial,
  vertexData: Record<string, ArrayLike<number>> = triangle,
) {
  return new Mesh(scene, { material, vertexData });
}

/** Decodes the active indirect rows of every forward bucket pass, in pass order. */
export function bucketDraws(scene: Scene, graph: any) {
  return forwardPasses(graph)
    .filter((pass: any) => pass.indirect)
    .flatMap((pass: any) => {
      const buffer = graph.resources.buffers.find(
        (buffer: any) => buffer.id === pass.indirect.resource,
      );
      const view = scene.core.array(buffer.array).view;
      const draws = [];
      for (let row = 0; row * 8 < view.length; row++) {
        const [indices, instances, firstIndex, baseVertex, firstInstance] =
          view.subarray(row * 8, row * 8 + 5);
        if (instances)
          draws.push({
            pass: pass.id,
            indices,
            firstIndex,
            baseVertex,
            firstInstance,
          });
      }
      return draws;
    });
}