import * as THREE from "/three.js";
import { buildTerrain } from "./terrain-mesh.js";
// This renderer consumes snapshots, never connects to a Minecraft server.
const renderer = new THREE.WebGLRenderer({
  antialias: true,
  preserveDrawingBuffer: true,
});
renderer.outputColorSpace = THREE.SRGBColorSpace;
renderer.setPixelRatio(1);
document.body.append(renderer.domElement);
const scene = new THREE.Scene();
const gl = renderer.getContext();
const gpuInfo = gl.getExtension("WEBGL_debug_renderer_info");
window.rendererInfo = {
  vendor: gpuInfo
    ? gl.getParameter(gpuInfo.UNMASKED_VENDOR_WEBGL)
    : "unavailable",
  renderer: gpuInfo
    ? gl.getParameter(gpuInfo.UNMASKED_RENDERER_WEBGL)
    : "unavailable",
};
scene.background = new THREE.Color("#95c4eb");
scene.add(new THREE.HemisphereLight("#e9f3ff", "#73704e", 2.0));
const sun = new THREE.DirectionalLight("#fff4d6", 2.2);
sun.position.set(-40, 90, -30);
scene.add(sun);
const loader = new THREE.TextureLoader(),
  jsonCache = new Map(),
  textureCache = new Map(),
  resolvedModels = new Map();
const resourcePath = (ref, kind) =>
  `/assets/assets/${ref.includes(":") ? ref.split(":")[0] : "minecraft"}/${kind}/${ref.split(":").at(-1)}`;
async function json(path) {
  if (!jsonCache.has(path))
    jsonCache.set(
      path,
      fetch(path, { signal: AbortSignal.timeout(60000) }).then((r) => {
        if (!r.ok) throw new Error(`Minecraft asset ${path}: HTTP ${r.status}`);
        return r.json();
      }),
    );
  return jsonCache.get(path);
}
async function model(ref, chain = []) {
  if (chain.includes(ref)) throw new Error("Cyclic model");
  if (resolvedModels.has(ref)) return resolvedModels.get(ref);
  const raw = await json(resourcePath(ref, "models") + ".json");
  let parent = {};
  if (raw.parent && !raw.parent.includes("builtin/"))
    parent = await model(raw.parent, [...chain, ref]);
  const merged = {
    ...parent,
    ...raw,
    textures: { ...parent.textures, ...raw.textures },
  };
  resolvedModels.set(ref, merged);
  return merged;
}
function textureRef(m, ref) {
  let i = 0;
  while (ref?.startsWith("#") && i++ < 20) ref = m.textures[ref.slice(1)];
  return ref;
}
async function texture(ref) {
  if (!ref) return null;
  if (!textureCache.has(ref)) {
    // Cache the in-flight promise and failures as well as successful textures.
    // Missing vanilla assets must not trigger another request for every face.
    textureCache.set(
      ref,
      loader
        .loadAsync(resourcePath(ref, "textures") + ".png")
        .then((t) => {
          t.magFilter = THREE.NearestFilter;
          t.minFilter = THREE.NearestFilter;
          t.colorSpace = THREE.SRGBColorSpace;
          return t;
        })
        .catch(() => null),
    );
  }
  return textureCache.get(ref);
}
function parseState(s) {
  const [name, raw] = s.split("[");
  return {
    name,
    props: Object.fromEntries(
      (raw?.replace("]", "") || "")
        .split(",")
        .filter(Boolean)
        .map((p) => p.split("=")),
    ),
  };
}
function match(condition, props) {
  if (condition.OR) return condition.OR.some((c) => match(c, props));
  if (condition.AND) return condition.AND.every((c) => match(c, props));
  return Object.entries(condition).every(([k, v]) =>
    String(v).split("|").includes(props[k]),
  );
}
function selectModels(state, props) {
  if (state.variants) {
    for (const [key, v] of Object.entries(state.variants)) {
      const c = Object.fromEntries(
        key
          .split(",")
          .filter(Boolean)
          .map((p) => p.split("=")),
      );
      if (match(c, props)) return [Array.isArray(v) ? v[0] : v];
    }
  }
  return (state.multipart || [])
    .filter((p) => !p.when || match(p.when, props))
    .map((p) => (Array.isArray(p.apply) ? p.apply[0] : p.apply));
}
const faceData = {
  east: {
    normal: [1, 0, 0],
    corners: [
      [1, 0, 1],
      [1, 0, 0],
      [1, 1, 1],
      [1, 1, 0],
    ],
  },
  west: {
    normal: [-1, 0, 0],
    corners: [
      [0, 0, 0],
      [0, 0, 1],
      [0, 1, 0],
      [0, 1, 1],
    ],
  },
  up: {
    normal: [0, 1, 0],
    corners: [
      [0, 1, 1],
      [1, 1, 1],
      [0, 1, 0],
      [1, 1, 0],
    ],
  },
  down: {
    normal: [0, -1, 0],
    corners: [
      [0, 0, 0],
      [1, 0, 0],
      [0, 0, 1],
      [1, 0, 1],
    ],
  },
  south: {
    normal: [0, 0, 1],
    corners: [
      [0, 0, 1],
      [1, 0, 1],
      [0, 1, 1],
      [1, 1, 1],
    ],
  },
  north: {
    normal: [0, 0, -1],
    corners: [
      [1, 0, 0],
      [0, 0, 0],
      [1, 1, 0],
      [0, 1, 0],
    ],
  },
};
window.buildTerrain = async (snapshot) => {
  const unsupported = new Set(),
    stateCache = new Map();
  async function stateModels(s) {
    if (stateCache.has(s)) return stateCache.get(s);
    const { name, props } = parseState(s);
    let variants = [];
    try {
      const bs = await json(resourcePath(name, "blockstates") + ".json");
      for (const v of selectModels(bs, props))
        variants.push({ v, m: await model(v.model) });
    } catch (error) {
      unsupported.add(name);
      if (unsupported.size <= 8)
        console.warn(`Missing block model ${name}: ${error.message}`);
    }
    stateCache.set(s, variants);
    return variants;
  }
  return buildTerrain(
    snapshot,
    scene,
    faceData,
    stateModels,
    textureRef,
    texture,
    unsupported,
  );
};
const directions = {
  px: [
    [1, 0, 0],
    [0, 1, 0],
  ],
  nx: [
    [-1, 0, 0],
    [0, 1, 0],
  ],
  py: [
    [0, 1, 0],
    [0, 0, -1],
  ],
  ny: [
    [0, -1, 0],
    [0, 0, 1],
  ],
  pz: [
    [0, 0, 1],
    [0, 1, 0],
  ],
  nz: [
    [0, 0, -1],
    [0, 1, 0],
  ],
};
function renderScene(camera, requireGeometry = false) {
  if (gl.isContextLost())
    throw new Error("Graphics context lost while rendering terrain");
  renderer.render(scene, camera);
  const error = gl.getError();
  if (error !== gl.NO_ERROR)
    throw new Error(`WebGL failed to render terrain (error ${error})`);
  if (requireGeometry && renderer.info.render.triangles === 0)
    throw new Error(
      "Surface-map camera sees no terrain geometry. Check world coordinates and Minecraft assets.",
    );
}
window.renderFace = (p, face, size) => {
  renderer.setSize(size, size);
  const camera = new THREE.PerspectiveCamera(90, 1, 0.05, 512);
  camera.position.set(p.x, p.y, p.z);
  const [dir, up] = directions[face];
  camera.up.set(...up);
  camera.lookAt(p.x + dir[0], p.y + dir[1], p.z + dir[2]);
  renderScene(camera);
  return renderer.domElement.toDataURL("image/webp", 0.85);
};
window.renderMap = (size) => {
  const b = window.terrainBounds;
  renderer.setSize(size, size);
  const camera = new THREE.OrthographicCamera(
    -(b.maxX - b.minX) / 2,
    (b.maxX - b.minX) / 2,
    (b.maxZ - b.minZ) / 2,
    -(b.maxZ - b.minZ) / 2,
    0.1,
    1024,
  );
  camera.position.set((b.minX + b.maxX) / 2, 512, (b.minZ + b.maxZ) / 2);
  camera.up.set(0, 0, -1);
  camera.lookAt(camera.position.x, 0, camera.position.z);
  renderScene(camera, true);
  return renderer.domElement.toDataURL("image/webp", 0.9);
};
window.rendererReady = true;