import { getPath } from "./common.js";
import { loadGltf } from "./index2.js";
import { loadLight } from "./light.js";

if (!navigator.gpu) {
  throw new Error("WebGPU not supported on this browser.");
}

const adapter = await navigator.gpu.requestAdapter();
if (!adapter) {
  throw new Error("No WebGPU adapter");
}

const device = await adapter.requestDevice();

const canvas = document.querySelector("canvas");
canvas.width = canvas.clientWidth
canvas.height = canvas.clientHeight

const context = canvas.getContext("webgpu");
const canvasFormat = navigator.gpu.getPreferredCanvasFormat();
context.configure({
  device: device,
  format: canvasFormat,
});

const encoder = device.createCommandEncoder();

const renderPass = encoder.beginRenderPass({
  colorAttachments: [{
    view: context.getCurrentTexture().createView(),
    loadOp: "clear",
    clearValue: { r: 0.9, g: 0.5, b: 0.2, a: 1 },
    storeOp: "store",
  }]
});
renderPass.end();

const commandBuffer = encoder.finish();
device.queue.submit([commandBuffer]);

const memory = new WebAssembly.Memory({ initial: 258 * 2 });
const module = await WebAssembly.instantiateStreaming(fetch("src/module.wasm"), {
  env: {
    memory: memory,
    log: console.log,
  }
});

function createDepthTexture() {
  return device.createTexture({
    size: [canvas.width, canvas.height],
    format: 'depth24plus',
    usage: GPUTextureUsage.RENDER_ATTACHMENT,
  });
}

var depthTexture = undefined;

const eyeValueX = document.getElementById("eye-value-x");
const eyeValueY = document.getElementById("eye-value-y");
const eyeValueZ = document.getElementById("eye-value-z");

const yawValue = document.getElementById("yaw");
const pitchValue = document.getElementById("pitch");

function recreateDepth()
{
  if (canvas.clientWidth !== canvas.width || canvas.clientWidth !== canvas.height) {
    canvas.width = canvas.clientWidth;
    canvas.height = canvas.clientHeight;

    if (depthTexture !== undefined) {
      depthTexture.destroy();
    }
    depthTexture = createDepthTexture();
  }
}

const matrixSize = 4 * 4 * 4;
const float4Size = 4 * 4;
const float3Size = 4 * 3;
const viewUniformBufferSize = (matrixSize * 2) + (float4Size * 2);

const viewUniformBuffer = device.createBuffer({
  label: "view uniform buffer",
  size: viewUniformBufferSize,
  usage: GPUBufferUsage.UNIFORM | GPUBufferUsage.COPY_DST,
});

const cameraStateSize = (float3Size * 3) + (4 * 3) + (float3Size * 1);

const viewStateAddress = module.instance.exports.mem_alloc(viewUniformBufferSize);
const cameraStateAddress = module.instance.exports.mem_alloc(cameraStateSize);

module.instance.exports.camera_init(cameraStateAddress);

const gltfRenderer = await loadGltf(device, canvasFormat, viewUniformBuffer, memory, module);
const lightRenderer = await loadLight(device, canvasFormat, viewUniformBuffer);


const KEY = {
  A: 65,
  B: 66,
  C: 67,
  D: 68,
  E: 69,
  F: 70,
  G: 71,
  H: 72,
  I: 73,
  J: 74,
  K: 75,
  L: 76,
  M: 77,
  N: 78,
  O: 79,
  P: 80,
  Q: 81,
  R: 82,
  S: 83,
  T: 84,
  U: 85,
  V: 86,
  W: 87,
  X: 88,
  Y: 89,
  Z: 90,

  Left: 37,
  Up: 38,
  Right: 39,
  Down: 40,
};

const keyCodes = new Set(Object.values(KEY));
const keyState = {};
for (const code of Object.values(KEY)) {
  keyState[code] = false;
}

function handleKeydown(e)
{
  //console.log(e.keyCode);
  if (keyCodes.has(e.keyCode)) {
    keyState[e.keyCode] = true;
  }
}

function handleKeyup(e)
{
  if (keyCodes.has(e.keyCode)) {
    keyState[e.keyCode] = false;
  }
}

window.addEventListener('keydown', handleKeydown, false);
window.addEventListener('keyup', handleKeyup, false);

function updateView()
{
  const lu = keyState[KEY.W] === true;
  const ll = keyState[KEY.A] === true;
  const ld = keyState[KEY.S] === true;
  const lr = keyState[KEY.D] === true;

  const lal = keyState[KEY.Q] === true;
  const lar = keyState[KEY.E] === true;

  const ru = keyState[KEY.Up] === true;
  const rl = keyState[KEY.Left] === true;
  const rd = keyState[KEY.Down] === true;
  const rr = keyState[KEY.Right] === true;

  module.instance.exports.camera_move(cameraStateAddress,
                                      lu, ll, ld, lr,
                                      lal, lar,
                                      ru, rl, rd, rr);

  const aspect = canvas.width / canvas.height;

  module.instance.exports.camera_view_projection(cameraStateAddress,
                                                 viewStateAddress,
                                                 aspect);

  device.queue.writeBuffer(viewUniformBuffer, 0,
                           memory.buffer, viewStateAddress,
                           viewUniformBufferSize);

  const cameraStateF32 = new Float32Array(memory.buffer, cameraStateAddress, cameraStateSize);
  eyeValueX.innerHTML = cameraStateF32[0].toFixed(1);
  eyeValueY.innerHTML = cameraStateF32[1].toFixed(1);
  eyeValueZ.innerHTML = cameraStateF32[2].toFixed(1);
  yawValue.innerHTML = cameraStateF32[9].toFixed(2);
  pitchValue.innerHTML = cameraStateF32[10].toFixed(2);
}

function render2()
{
  recreateDepth();
  const colorView = context.getCurrentTexture().createView();

  updateView();

  {
    const encoder = device.createCommandEncoder();
    const renderPass = encoder.beginRenderPass({
      colorAttachments: [{
        view: colorView,
        loadOp: "clear",
        clearValue: { r: 0.2, g: 0.2, b: 0.4, a: 1 },
        storeOp: "store",
      }],
      depthStencilAttachment: {
        view: depthTexture.createView(),
        depthClearValue: 1.0,
        depthLoadOp: 'clear',
        depthStoreOp: 'store',
      },
    });

    gltfRenderer.render(renderPass);
    lightRenderer.render(renderPass);

    renderPass.end();

    const commandBuffer = encoder.finish();
    device.queue.submit([commandBuffer]);
  }

  requestAnimationFrame(render2);
}
requestAnimationFrame(render2);