import { Render } from "matter-js";

/**
 * @description Override method for matter-js render. This is most importan part
 * of this project. Must be improved.
 * @class VisualRender
 */
class VisualRender {

    constructor() {
        (Render as any).getTexture = this.getTexture;
        (Render as any).drawSolid = this.drawSolid;
        (Render as any).bodies = this.overrideRenderFunction;
    }

    /**
     * Description Override method for Render.bodies
     * @private
     * @method Render.bodies
     * @param {render} render
     * @param {body[]} bodies
     * @param {RenderingContext} context
     */
    private overrideRenderFunction(render, bodies, context) {

        const c = context;
        const options = render.options,
            showInternalEdges = options.showInternalEdges || !options.wireframes;
        let body, part, i, k;

        for (i = 0; i < bodies.length; i++) {
            body = bodies[i];

            if (!body.render.visible) {
                continue;
            }

            // handle compound parts
            for (k = body.parts.length > 1 ? 1 : 0; k < body.parts.length; k++) {
                part = body.parts[k];

                if (!part.render.visible) {
                    continue;
                }

                if (options.showSleeping && body.isSleeping) {
                    c.globalAlpha = 0.5 * part.render.opacity;
                } else if (part.render.opacity !== 1) {
                    c.globalAlpha = part.render.opacity;
                }

                // debug line - remove on prod
                if (part.render.wireframes === true) {
                    this.drawSolid(c, part, showInternalEdges, options);
                }

                if (part.render.sprite && part.render.visualComponent && !options.wireframes) {

                    c.translate(part.position.x, part.position.y);
                    c.rotate(part.angle);
                    // tslint:disable-next-line:no-unused-expression
                    () => this.drawSolid(c, part, showInternalEdges, options);
                    if (part.render.visualComponent) {
                        part.render.visualComponent.drawComponent(c, part);
                    }
                    c.rotate(-part.angle);
                    c.translate(-part.position.x, -part.position.y);

                } else {

                    this.drawSolid(c, part, showInternalEdges, options);

                }

                c.globalAlpha = 1;
            }
        }
    }

    private getTexture(render, imagePath): HTMLImageElement {

        let image = render.textures[imagePath];
        if (image) { return image; }
        image = render.textures[imagePath] = new Image();
        image.src = imagePath;
        return image;

    }

    private drawSolid(c, part, showInternalEdges, options) {

        if (part.circleRadius) {
            c.beginPath();
            c.arc(part.position.x, part.position.y, part.circleRadius, 0, 2 * Math.PI);
        } else {
            c.beginPath();
            c.moveTo(part.vertices[0].x, part.vertices[0].y);

            for (let j = 1; j < part.vertices.length; j++) {
                if (!part.vertices[j - 1].isInternal || showInternalEdges) {
                    c.lineTo(part.vertices[j].x, part.vertices[j].y);
                } else {
                    c.moveTo(part.vertices[j].x, part.vertices[j].y);
                }

                if (part.vertices[j].isInternal && !showInternalEdges) {
                    c.moveTo(part.vertices[(j + 1) % part.vertices.length].x, part.vertices[(j + 1) % part.vertices.length].y);
                }
            }

            c.lineTo(part.vertices[0].x, part.vertices[0].y);
            c.closePath();
        }

        if (!options.wireframes) {
            c.fillStyle = part.render.fillStyle;

            if (part.render.lineWidth) {
                c.lineWidth = part.render.lineWidth;
                c.strokeStyle = part.render.strokeStyle;
                c.stroke();
            }

            c.fill();
        } else {
            c.lineWidth = 1;
            c.strokeStyle = "#bbb";
            c.stroke();
        }

    }

}

export default VisualRender;