import * as THREE from "three";
import { OrbitControls } from "three/addons/controls/OrbitControls.js";
import { EffectComposer } from "three/addons/postprocessing/EffectComposer.js";
import { RenderPass } from "three/addons/postprocessing/RenderPass.js";
import { UnrealBloomPass } from "three/addons/postprocessing/UnrealBloomPass.js";
import { paintIdentify, paintRgb } from "../panel-paint.js";
import { hexFrameEdges, panelPlacement, PORTAL } from "../portal-geometry.js";

const HOST_STYLES = `
  :host {
    display: block;
    width: 100%;
    height: 100%;
  }
  .mount {
    width: 100%;
    height: 100%;
  }
`;

const FRAME_MAT = new THREE.MeshStandardMaterial({
  color: 0x0a0a0a,
  roughness: 0.92,
  metalness: 0.05,
});

const BASE_MAT = new THREE.MeshStandardMaterial({
  color: 0x050505,
  roughness: 0.95,
  metalness: 0.02,
});

export class PortalViewport extends HTMLElement {
  constructor() {
    super();
    /** @type {Map<number, object>} */
    this._panels = new Map();
    this._raf = 0;
  }

  connectedCallback() {
    if (this.shadowRoot) return;
    const root = this.attachShadow({ mode: "open" });
    root.innerHTML = `<style>${HOST_STYLES}</style><div class="mount"></div>`;
    this._mount = root.querySelector(".mount");

    this._scene = new THREE.Scene();
    this._scene.background = new THREE.Color(0x1a1a1e);
    this._scene.fog = new THREE.Fog(0x1a1a1e, 8, 22);

    this._camera = new THREE.PerspectiveCamera(50, 1, 0.1, 50);
    this._camera.position.set(0, 1.0, 3.8);

    this._renderer = new THREE.WebGLRenderer({ antialias: true });
    this._renderer.setPixelRatio(Math.min(window.devicePixelRatio, 2));
    this._renderer.toneMapping = THREE.ReinhardToneMapping;
    this._renderer.toneMappingExposure = 1.15;
    this._mount.appendChild(this._renderer.domElement);

    this._composer = new EffectComposer(this._renderer);
    this._composer.addPass(new RenderPass(this._scene, this._camera));
    this._bloom = new UnrealBloomPass(
      new THREE.Vector2(1, 1),
      0.85,
      0.35,
      0.15,
    );
    this._composer.addPass(this._bloom);

    this._controls = new OrbitControls(this._camera, this._renderer.domElement);
    this._controls.enableDamping = true;
    this._controls.target.set(0, 0.95, 0);
    this._controls.minDistance = 2.2;
    this._controls.maxDistance = 8;

    this._scene.add(new THREE.AmbientLight(0x332222, 0.25));
    const key = new THREE.DirectionalLight(0xffeedd, 0.35);
    key.position.set(2, 5, 4);
    this._scene.add(key);
    const rim = new THREE.DirectionalLight(0x445566, 0.2);
    rim.position.set(-3, 2, -2);
    this._scene.add(rim);

    this._buildEnvironment();
    this._buildFrame();
    this._buildBase();

    this._onResize = () => this._resize();
    window.addEventListener("resize", this._onResize);
    this._resize();
    this._tick();
  }

  disconnectedCallback() {
    window.removeEventListener("resize", this._onResize);
    cancelAnimationFrame(this._raf);
    this._renderer?.dispose();
    this._composer?.dispose();
  }

  _buildEnvironment() {
    const floor = new THREE.Mesh(
      new THREE.PlaneGeometry(14, 14),
      new THREE.MeshStandardMaterial({ color: 0x2a2a30, roughness: 0.9, metalness: 0 }),
    );
    floor.rotation.x = -Math.PI / 2;
    floor.position.y = 0;
    this._scene.add(floor);

    const back = new THREE.Mesh(
      new THREE.PlaneGeometry(12, 6),
      new THREE.MeshStandardMaterial({ color: 0x3a3a42, roughness: 0.95 }),
    );
    back.position.set(0, 2.5, -4);
    this._scene.add(back);
  }

  _buildFrame() {
    const { height, frameDepth } = PORTAL;
    const group = new THREE.Group();

    for (const edge of hexFrameEdges()) {
      if (edge.isFloor) continue;

      const ax = edge.outerA[0];
      const az = edge.outerA[1];
      const bx = edge.outerB[0];
      const bz = edge.outerB[1];
      const dx = bx - ax;
      const dz = bz - az;
      const len = Math.hypot(dx, dz);
      const beam = new THREE.Mesh(
        new THREE.BoxGeometry(len, height, frameDepth),
        FRAME_MAT,
      );
      beam.position.set((ax + bx) / 2, height / 2, (az + bz) / 2);
      beam.rotation.y = Math.atan2(dx, dz);
      group.add(beam);

      const lip = new THREE.Mesh(
        new THREE.BoxGeometry(len * 0.98, frameDepth * 0.6, frameDepth * 0.35),
        FRAME_MAT,
      );
      lip.position.set((ax + bx) / 2, height - frameDepth * 0.25, (az + bz) / 2);
      lip.rotation.y = Math.atan2(dx, dz);
      group.add(lip);
    }

    this._scene.add(group);
  }

  _buildBase() {
    const { apothem, baseThickness, baseExtend } = PORTAL;
    const w = apothem * 2 + baseExtend * 2;
    const base = new THREE.Mesh(
      new THREE.BoxGeometry(w, baseThickness, w * 0.85),
      BASE_MAT,
    );
    base.position.set(0, baseThickness / 2, 0.05);
    this._scene.add(base);
  }

  _resize() {
    const w = this.clientWidth || 1;
    const h = this.clientHeight || 1;
    this._camera.aspect = w / h;
    this._camera.updateProjectionMatrix();
    this._renderer.setSize(w, h);
    this._composer.setSize(w, h);
    this._bloom.resolution.set(w, h);
  }

  _tick() {
    this._raf = requestAnimationFrame(() => this._tick());
    this._controls.update();
    this._composer.render();
  }

  /** @param {import('../api.js').PanelConfig[]} panels */
  setPanels(panels) {
    if (!this.shadowRoot) this.connectedCallback();
    for (const entry of this._panels.values()) {
      this._scene.remove(entry.mesh);
      entry.texture.dispose();
      entry.material.dispose();
      entry.geometry.dispose();
    }
    this._panels.clear();

    for (const panel of panels) {
      const place = panelPlacement(panel.position, panel.width);
      const geometry = new THREE.PlaneGeometry(place.width, place.height);
      const canvas = document.createElement("canvas");
      canvas.width = panel.width;
      canvas.height = panel.height;
      const ctx = canvas.getContext("2d");
      const texture = new THREE.CanvasTexture(canvas);
      texture.magFilter = THREE.NearestFilter;
      texture.minFilter = THREE.NearestFilter;
      texture.colorSpace = THREE.SRGBColorSpace;

      const material = new THREE.MeshBasicMaterial({
        map: texture,
        side: THREE.FrontSide,
        toneMapped: false,
      });
      const mesh = new THREE.Mesh(geometry, material);
      mesh.position.set(place.pos[0], place.pos[1], place.pos[2]);
      mesh.rotation.set(place.rot[0], place.rot[1], place.rot[2]);

      this._scene.add(mesh);

      this._panels.set(panel.index, {
        mesh,
        geometry,
        material,
        canvas,
        ctx,
        texture,
        panel,
      });
    }
  }

  /**
   * @param {number} index
   * @param {number[] | Uint8Array} rgb
   * @param {number} width
   * @param {number} height
   * @param {boolean} identify
   */
  updatePanel(index, rgb, width, height, identify) {
    const entry = this._panels.get(index);
    if (!entry) return;
    if (identify) {
      paintIdentify(entry.ctx, entry.canvas, index, entry.panel.width, entry.panel.height);
    } else {
      paintRgb(entry.ctx, entry.canvas, rgb, width, height);
    }
    entry.texture.needsUpdate = true;
  }
}

customElements.define("portal-viewport", PortalViewport);