import { DRACOLoader } from 'three/examples/jsm/loaders/DRACOLoader';
import { GLTF, GLTFLoader } from 'three/examples/jsm/loaders/GLTFLoader';

/**
 * A basic loading manager.
 *
 * @module
 */

export class DIVELoadingManager {
    private gltfloader: GLTFLoader;
    private dracoloader: DRACOLoader;
    // ... maybe extend with other loaders later

    constructor() {
        this.gltfloader = new GLTFLoader();
        this.dracoloader = new DRACOLoader();
        this.dracoloader.setDecoderPath(
            'https://www.gstatic.com/draco/v1/decoders/',
        );
        this.gltfloader.setDRACOLoader(this.dracoloader);
    }

    private progress: Map<string, number> = new Map<string, number>();

    public async LoadGLTF(uri: string): Promise<GLTF> {
        const progEvent = (p: ProgressEvent<EventTarget>): void => {
            this.progress.set(uri, p.loaded / p.total);
        };

        this.progress.set(uri, 0);

        return new Promise<GLTF>((resolve, reject) => {
            this.gltfloader
                .loadAsync(uri, progEvent)
                .then(resolve)
                .catch(reject);
        });
    }

    public PollProgress(): number {
        let total = 0;
        this.progress.forEach((progress: number) => {
            total += progress;
        });

        if (this.progress.size === 0) return 1;
        return total / this.progress.size;
    }
}