import {EventEmitter} from 'events'
import Worker from '../workers/Terrain.worker'

export default class Terrain extends EventEmitter {
    constructor(name, x, z, heightmap, blendmap, scene) {
        super();
        this.name = name;
        this.scene = scene;
        this.x = x;
        this.z = z;
        this.mesh = null;
        this.worker = new Worker();
        this.heightmap = heightmap;
        this.blendmap = blendmap;
        this.subdivisions = 64;
        this.filter = [1, 1, 1];
        this.heightmapBuffer = null;
        this.blendmapBuffer = null;
        this.SIZE = 32.5;
        this.MIN_HEIGHT = 0;
        this.MAX_HEIGHT = 1;

        this.getHeightmapPixels(heightmap, blendmap);

        this.worker.onmessage = event => {
            if(event.data.generated) {
                this.heights = event.data.heights;
                this.mesh = this.scene.engine.loader.loadToVAO(
                    this.name,
                    event.data.vertices,
                    event.data.indices,
                    event.data.texCoords,
                    event.data.normals
                );
                this.emit('ready', event.data);
            }
        };
    }

    getHeights(positions) {
        return new Promise((res, rej) => {
            this.worker.postMessage({
                getHeights: positions
            });

            this.worker.onmessage = event => {
                if(event.data) {
                    res(event.data)
                }
            };
        });
    }

    getHeightmapPixels(heightmap, blendmap) {
        if(blendmap && heightmap) {
            let canvas = document.createElement('canvas');
            let canvas2 = document.createElement('canvas');

            canvas.width = canvas2.width =  heightmap.image.width;
            canvas.height = canvas2.height =  heightmap.image.height;
            let ctx = canvas.getContext('2d');
            let ctx2 = canvas2.getContext('2d');
            // ctx.translate(0, height);
            // ctx.scale(1, -1);
            ctx.drawImage(heightmap.image, 0, 0);

            // ctx2.translate(blendmap.image.width/2, blendmap.image.height/2);
            // ctx2.scale(-1, -1);
            ctx2.drawImage(blendmap.image, 0, 0);

            this.heightmapBuffer = ctx.getImageData(0, 0, heightmap.image.width, heightmap.image.height).data;
            this.blendmapBuffer = ctx2.getImageData(0, 0,  blendmap.image.width, blendmap.image.height).data;
            this.worker.postMessage({

                config: {
                    heightmap: this.heightmapBuffer,
                    blendmap: this.blendmapBuffer,
                    heightmapWidth: heightmap.image.width,
                    heightmapHeight: heightmap.image.height,
                    SIZE: this.SIZE,
                    subdivisions: this.subdivisions,
                    filter: this.filter,
                    MAX_HEIGHT: this.MAX_HEIGHT,
                    MIN_HEIGHT: this.MIN_HEIGHT
                }
            })
        }

    }
}