import { Graph } from '../../Graph';
import { StaticLayout } from './StaticLayout';

class GridLayout extends StaticLayout {

    apply (graph: Graph): void {

        const bbox = graph.boundingBox();
        const cx = (bbox[1] + bbox[3]) / 2;
        const cy = (bbox[0] + bbox[2]) / 2;
        const w = 0.8 * Math.abs(bbox[1] - bbox[3]);
        const h = 0.8 * Math.abs(bbox[0] - bbox[2]);

        const nodes = graph.nodes();
        const ratio = w/h;

        let r = 0,
            c = 0;

        while (r * c < nodes.length) {
            c / r < ratio ? ++c : ++r;
        }

        const t = cy + h / 2;
        const l = cx - w / 2;
        const dx = w / c;
        const dy = h / r;

        let row = 0,
            col = 0;

        nodes.forEach(node => {
            node.x = l + col * dx;
            node.y = t - row * dy;
            if (col++ === c) {
                col = 0;
                row++;
            }
        });

    }

}

export {
    GridLayout
}