import * as THREE from "three";
import ForceGraph3D from "3d-force-graph";
import SpriteText from "three-spritetext";
import { union } from "./utils/set_utils.js";

const IMG_SCALE = 16;
const MAIN_IMG_SCALE = 80;
const OBJECT_SCALE = 10;

export default function buildGraph({ db, objects, handlers }) {
  const linkable = {};
  const groups = {};
  const data = { nodes: [], links: [] };

  // console.log(db);

  /**
   * load nodes and links
   */

  db.page.forEach((item, index) => {
    const node = {
      title: index + 1 + " " + item.title,
      id: index,
      data: item,
      groups: [],
    };
    data.nodes.push(node);
    for (let tagIndex = 0; tagIndex < 8; tagIndex += 1) {
      const group = item["tag_" + tagIndex];
      if (!group) continue;
      group -= 1;
      node.groups.push(group);
      if (group in groups) {
        groups[group].push(index);
      } else {
        groups[group] = [index];
      }
      if (group in linkable) {
        data.links.push({
          source: choice(linkable[group]),
          // source: linkable[group][0],
          target: index,
        });
        // option: don't link to the root node more than once
        // if (window.location.hash === "#dense" && linkable[group][0]) {
        if (linkable[group][0]) {
          linkable[group].push(index);
        } else {
          linkable[group] = [index];
        }
      } else {
        linkable[group] = [index];
      }
    }
  });

  /**
   * find common links
   */
  data.links.forEach((link) => {
    const a = data.nodes[link.source];
    const b = data.nodes[link.target];

    !a.links && (a.links = []);
    !b.links && (b.links = []);
    a.links.push(link);
    b.links.push(link);
  });

  const highlightNodes = new Set();
  const highlightLinks = new Set();
  let selectedNode = null;

  /** build group */

  let graph = ForceGraph3D();
  graph(document.querySelector("#graph"))
    .graphData(data)
    .showNavInfo(false)
    .nodeLabel((node) => node.title)
    .nodeThreeObject((node) => {
      let sprite, material, texture, video;
      if (node.data.object) {
        const object = node.data.object;
        var box = new THREE.Box3().setFromObject(object);
        var center = new THREE.Vector3();
        box.getCenter(center);
        object.position.sub(center);
        object.scale.set(OBJECT_SCALE, OBJECT_SCALE, OBJECT_SCALE);
        return object;
      } else if (node.data.thumbnail?.uri) {
        if (node.data.thumbnail.type === "video") {
          video = document.createElement("video");
          video.src = node.data.thumbnail.uri;
          video.muted = true;
          video.loop = true;
          video.autoplay = true;
          video.play();
          texture = new THREE.VideoTexture(video);
        } else {
          texture = new THREE.TextureLoader().load(node.data.thumbnail.uri);
        }
        // console.log(imgTexture);
        const aspect = node.data.thumbnail.width / node.data.thumbnail.height;
        material = new THREE.SpriteMaterial({ map: texture });
        sprite = new THREE.Sprite(material);
        if (node.id === 0) {
          sprite.scale.set(MAIN_IMG_SCALE, MAIN_IMG_SCALE / aspect);
        } else {
          sprite.scale.set(IMG_SCALE, IMG_SCALE / aspect);
        }
        return sprite;
      } else {
        sprite = new SpriteText(
          node.title.split(/[ :]+/).slice(0, 3).join(" ")
        );
        sprite.material.depthWrite = false; // make sprite background transparent
        sprite.color = "#888888"; // colors[node.groups[0]]; // node.groups.length - 1]];
        sprite.textHeight = 4;
        return sprite;
      }
    })
    .onNodeClick(handlers.click);

  // TrackballControls
  graph.controls().addEventListener("change", () => {
    const position = graph.cameraPosition();
    // console.log(position);
  });

  const initialZoom = () => {
    const distance = 20000;
    let angle = 0;
    graph.cameraPosition(
      {
        x: distance * Math.sin(angle),
        z: distance * Math.cos(angle),
      },
      { x: 0, y: 0, z: 0 },
      0
    );
    setTimeout(() => zoomOut(1000), 1000);
  };

  const zoomOut = (duration = 1000) => {
    const distance = 415;
    let angle = 0;
    graph.cameraPosition(
      {
        x: distance * Math.sin(angle),
        z: distance * Math.cos(angle),
      },
      { x: 0, y: 0, z: 0 },
      duration
    );
  };

  const zoomIn = () => {
    const distance = 200;
    let angle = 0;
    graph.cameraPosition(
      {
        x: distance * Math.sin(angle),
        z: distance * Math.cos(angle),
      },
      { x: 0, y: 0, z: 0 },
      1000
    );
  };

  const handleSelect = (category) => {
    if (!category) {
      graph.graphData(data);
      zoomOut();
      return;
    }
    const { nodes, links } = data;
    const visible = new Set();

    const selectedData = {};
    selectedData.nodes = nodes.filter((node) => {
      for (let tagIndex = 0; tagIndex < 8; tagIndex += 1) {
        const group = node.data["tag_" + tagIndex];
        if (!group) continue;
        if (group === category) {
          visible.add(node.id);
          return true;
        }
      }
      return false;
    });
    selectedData.links = links.filter((link) => {
      const { source, target } = link;
      return visible.has(source.id) && visible.has(target.id);
    });
    // console.log(selectedData);
    graph.graphData(selectedData);
    zoomIn();
  };

  // graph.d3Force("charge").strength(-150);

  // camera orbit
  initialZoom();

  return {
    onSelect: handleSelect,
  };
  // stars();
}

const randint = (limit) => Math.floor(Math.random() * limit);
const choice = (list) => list[randint(list.length)];
const commonGroups = (a, b) => union(a.groups, b.groups);