import * as THREE from "three";
import { OrbitControls } from "three/addons/controls/OrbitControls.js";
import {
  SCENE_BACKGROUND,
  GROUND_SIZE,
  GRID_CELL_SIZE,
} from "../config/gameConfig.js";

export class SceneSetup {
  constructor() {
    // Basic scene setup
    this.scene = new THREE.Scene();
    this.scene.background = new THREE.Color(SCENE_BACKGROUND);

    // Camera
    this.camera = new THREE.PerspectiveCamera(
      60,
      window.innerWidth / window.innerHeight,
      0.1,
      2000
    );
    this.camera.position.set(20, 22, 24);

    // Renderer
    this.renderer = new THREE.WebGLRenderer({ antialias: true });
    this.renderer.setSize(window.innerWidth, window.innerHeight);
    this.renderer.shadowMap.enabled = true;
    document.body.appendChild(this.renderer.domElement);

    // Controls
    this.controls = new OrbitControls(this.camera, this.renderer.domElement);
    this.controls.target.set(0, 0, 0);
    this.controls.enableDamping = true;

    // Camera movement config
    this.CAMERA_MOVE_SPEED = 18; // units per second in world-space
    // Bounds relative to ground size, keep a small margin inside edges
    const half = GROUND_SIZE / 2;
    this.CAMERA_MIN_X = -half + 2;
    this.CAMERA_MAX_X = half - 2;
    this.CAMERA_MIN_Z = -half + 2;
    this.CAMERA_MAX_Z = half - 2;

    // Setup lighting
    this.setupLighting();

    // Setup ground
    this.ground = this.setupGround();

    // Setup grid
    this.grid = this.setupGrid();

    // Handle window resize
    window.addEventListener("resize", () => this.onWindowResize());
  }

  setupLighting() {
    const hemi = new THREE.HemisphereLight(0xffffff, 0x404040, 0.6);
    this.scene.add(hemi);

    const dirLight = new THREE.DirectionalLight(0xffffff, 1.0);
    dirLight.position.set(8, 20, 8);
    dirLight.castShadow = true;
    dirLight.shadow.mapSize.set(1024, 1024);
    this.scene.add(dirLight);
  }

  setupGround() {
    const groundGeo = new THREE.PlaneGeometry(GROUND_SIZE, GROUND_SIZE);
    const groundMat = new THREE.MeshStandardMaterial({ color: 0x1d6e2f });
    const ground = new THREE.Mesh(groundGeo, groundMat);
    ground.rotation.x = -Math.PI / 2;
    ground.receiveShadow = true;
    ground.name = "ground";
    this.scene.add(ground);
    return ground;
  }

  setupGrid() {
    const divisions = Math.floor(GROUND_SIZE / GRID_CELL_SIZE);
    const grid = new THREE.GridHelper(
      GROUND_SIZE,
      divisions,
      0x8ab4f8,
      0x3a97ff
    );
    grid.position.y = 0.02; // avoid z-fighting with ground
    grid.material.transparent = true;
    grid.material.opacity = 0.35;
    grid.renderOrder = 0;
    this.scene.add(grid);
    return grid;
  }

  clampToBounds(vec3) {
    vec3.x = Math.min(this.CAMERA_MAX_X, Math.max(this.CAMERA_MIN_X, vec3.x));
    vec3.z = Math.min(this.CAMERA_MAX_Z, Math.max(this.CAMERA_MIN_Z, vec3.z));
    return vec3;
  }

  // Move camera and controls target horizontally in world space while keeping height
  moveCamera(direction, deltaTime) {
    // direction: {x: -1|0|1, z: -1|0|1}
    if (!direction || (direction.x === 0 && direction.z === 0)) return;

    // Compute normalized planar direction
    const move = new THREE.Vector3(direction.x, 0, direction.z);
    if (move.lengthSq() === 0) return;
    move.normalize().multiplyScalar(this.CAMERA_MOVE_SPEED * deltaTime);

    // Maintain current height
    const currentY = this.camera.position.y;

    // Move both camera and target so orbit feel is preserved
    const newCamPos = this.camera.position.clone().add(move);
    const newTarget = this.controls.target.clone().add(move);

    // Clamp within bounds
    this.clampToBounds(newCamPos);
    this.clampToBounds(newTarget);

    // Apply positions (preserve camera height)
    newCamPos.y = currentY;
    this.camera.position.copy(newCamPos);
    this.controls.target.copy(newTarget);
    // Let OrbitControls smoothing handle interpolation
  }

  onWindowResize() {
    this.camera.aspect = window.innerWidth / window.innerHeight;
    this.camera.updateProjectionMatrix();
    this.renderer.setSize(window.innerWidth, window.innerHeight);
  }

  render(gameState) {
    // Optionally pass gameState so we can update transient visuals like electric arcs
    this.controls.update();

    // Per-frame visual updates for towers (electric arcs fade/cleanup)
    if (gameState && Array.isArray(gameState.towers)) {
      const now = performance.now();
      for (const t of gameState.towers) {
        if (t?.updateElectricArcs) {
          t.updateElectricArcs(now);
        }
      }
    }

    this.renderer.render(this.scene, this.camera);
  }
}