import * as THREE from 'three';
import type { MeshDto } from '../backend/dto';

export class GeometryCache {
    private readonly items = new Map<string, THREE.BufferGeometry>();

    public has(id: string): boolean {
        return this.items.has(id);
    }

    public get(id: string): THREE.BufferGeometry | undefined {
        return this.items.get(id);
    }

    public set(id: string, payload: THREE.BufferGeometry) {
        this.items.set(id, payload);
    }

    public createMesh(id: string, dto: MeshDto): THREE.BufferGeometry {
        let geometry = this.get(id);
        if (geometry)
            return geometry;

        geometry = new THREE.BufferGeometry();
        geometry.userData.id = id;

        geometry.setAttribute('position', new THREE.BufferAttribute(dto.vertices, 3));
        geometry.setAttribute('normal', new THREE.BufferAttribute(dto.normals, 3));
        geometry.setIndex(new THREE.BufferAttribute(dto.indices, 1));

        this.set(id, geometry);

        return geometry;
    }

    unset(id: string) {
        const geometry = this.get(id);
        if (geometry) {
            geometry.dispose();
            this.items.delete(id);
        }
    }
}