AltitudeWeb/frontend/src/app/particles/services/intersection-plane.service.ts

import {Injectable} from '@angular/core';
import * as THREE from 'three';
import {RendererService} from './renderer.service';

/**
 * Service responsible for managing the intersection plane
 */
@Injectable({
  providedIn: 'root'
})
export class IntersectionPlaneService {
  private intersectionPlane!: THREE.Mesh;
  private planePosition: number = 8; // Position in 1/16th of a block

  constructor(private rendererService: RendererService) {
  }

  /**
   * Creates the intersection plane and adds it to the scene
   */
  createIntersectionPlane(): THREE.Mesh {
    const planeGeometry = new THREE.PlaneGeometry(3, 3);
    const planeMaterial = new THREE.MeshBasicMaterial({
      color: 0x00AA00,
      transparent: true,
      opacity: 0.05,
      side: THREE.DoubleSide
    });

    this.intersectionPlane = new THREE.Mesh(planeGeometry, planeMaterial);
    this.intersectionPlane.position.z = 0;
    // Center the plane vertically with the player (player is about 2 blocks tall)
    this.intersectionPlane.position.y = 1;
    this.rendererService.scene.add(this.intersectionPlane);

    return this.intersectionPlane;
  }

  /**
   * Updates the plane position based on slider value
   */
  updatePlanePosition(value: number): void {
    this.planePosition = value;
    // Convert from 1/16th block to Three.js units
    const position = (this.planePosition / 16) - 0.5; // Center at 0

    // Check if the plane is rotated vertically (looking from above/below)
    if (Math.abs(this.intersectionPlane.rotation.x) > 0.1) {
      // For vertical orientation, adjust Y position
      this.intersectionPlane.position.y = position * (this.intersectionPlane.rotation.x > 0 ? -1 : 1);
      // Reset x and z positions
      this.intersectionPlane.position.x = 0;
      this.intersectionPlane.position.z = 0;
    } else {
      const rotation = this.intersectionPlane.rotation.y;

      if (Math.abs(rotation) < 0.1 || Math.abs(rotation - Math.PI) < 0.1) {
        // Camera in front (0) or behind (PI)
        const direction = Math.abs(rotation) < 0.1 ? 1 : -1;
        this.intersectionPlane.position.z = position * direction;
        // Reset x position to avoid cumulative changes
        this.intersectionPlane.position.x = 0;
      } else {
        // Camera on right (PI/2) or left (-PI/2)
        const direction = rotation > 0 ? 1 : -1;
        this.intersectionPlane.position.x = position * direction;
        // Reset z position to avoid cumulative changes
        this.intersectionPlane.position.z = 0;
      }
    }
  }

  /**
   * Updates the plane orientation based on camera position
   */
  updatePlaneOrientation(camera: THREE.Camera): void {
    if (!this.intersectionPlane) return;

    // Check if camera is looking from above or below first
    const verticalAngle = Math.atan2(
      camera.position.y,
      Math.sqrt(camera.position.x * camera.position.x + camera.position.z * camera.position.z)
    );

    // Threshold angle for considering the camera to be above/below (about 45 degrees)
    const verticalThreshold = Math.PI / 4;

    if (verticalAngle > verticalThreshold) {
      // Camera is above
      this.intersectionPlane.rotation.x = -Math.PI / 2;
      this.intersectionPlane.rotation.y = 0;
      this.updatePlaneMaterial(0xAA0000);
    } else if (verticalAngle < -verticalThreshold) {
      // Camera is below
      this.intersectionPlane.rotation.x = Math.PI / 2;
      this.intersectionPlane.rotation.y = 0;
      this.updatePlaneMaterial(0xAA0000);
    } else {
      // Reset rotation.x as we're now in the horizontal plane
      this.intersectionPlane.rotation.x = 0;

      // Calculate the angle between camera and player (in the XZ plane)
      const cameraAngle = Math.atan2(
        camera.position.x,
        camera.position.z
      );

      // Determine which quadrant the camera is in with a 45-degree offset
      const quadrant = Math.floor((cameraAngle + Math.PI + Math.PI / 4) / (Math.PI / 2)) % 4;

      // Rotate the plane to face the camera
      if (quadrant === 0) {
        this.intersectionPlane.rotation.y = 0; // Camera in front
        this.updatePlaneMaterial(0x00AA00);
      } else if (quadrant === 1) {
        this.intersectionPlane.rotation.y = Math.PI / 2; // Camera on right
        this.updatePlaneMaterial(0x0000AA);
      } else if (quadrant === 2) {
        this.intersectionPlane.rotation.y = Math.PI; // Camera behind
        this.updatePlaneMaterial(0x00AA00);
      } else {
        this.intersectionPlane.rotation.y = -Math.PI / 2; // Camera on left
        this.updatePlaneMaterial(0x0000AA);
      }
    }

    // Update position after rotation change
    this.updatePlanePosition(this.planePosition);
  }

  /**
   * Updates the plane material color
   */
  private updatePlaneMaterial(color: number): void {
    this.intersectionPlane.material = new THREE.MeshBasicMaterial({
      color: color,
      transparent: true,
      opacity: 0.05,
      side: THREE.DoubleSide
    });
  }

  /**
   * Gets the intersection plane
   */
  getIntersectionPlane(): THREE.Mesh {
    return this.intersectionPlane;
  }

  /**
   * Gets the current plane position
   */
  getPlanePosition(): number {
    return this.planePosition;
  }
}