import type { PrePointOnShape } from '../point-on-shape/point-on-shape.js';
import type { Circle } from '../geometry/circle.js';
import type { MatMeta } from '../mat/mat-meta.js';
import { addToCpTree } from '../mat/add-to-cp-tree.js';
import { getCloseByCpIfExist } from '../mat/get-closeby-cp-if-exist.js';
import { calcPosOrder } from '../point-on-shape/calc-pos-order.js';
import { isPosCorner } from '../point-on-shape/is-pos-corner.js';
import { getPosCorner$ } from '../point-on-shape/get-pos-corner.js';


/**
 * @hidden
 * Add a 1-prong to the MAT.
 * @param cpTrees
 * @param pos 
 */
function add1Prong(
        meta: MatMeta,
        radius: number,
        center: number[],
        pos: PrePointOnShape) {

    if (isPosCorner(pos) && getPosCorner$(pos).isDull) {
        // This is a 1-prong at a dull corner.
        
        // FUTURE
        // Remove this line, uncomment piece below it and implement the 
        // following strategy to find the 3-prongs: if deltas are conjoined due 
        // to dull corner, split the conjoinment by inserting successively 
        // closer (binary division) 2-prongs. If a 2-prong actually fails, 
        // simply remove the 1-prong at the dull corner. In this way **all** 
        // terminal points are found, e.g. zoom in on top left leg of ant.
        // Afterthought: there is a better way - split points by two prongs.

        //toRemove.push(posNode); // this!
        
        // if (typeof _debug_ !== 'undefined') { 
            // _debug_.generated.elems.oneProngAtDullCorner.push(pos);
        // }

        return;
    }
    
    const circle: Circle = { radius, center };
    
    const order = calcPosOrder(circle.center, pos);
    // Make sure there isn't already a ContactPoint close by - it can cause
    // floating point stability issues.
    if (getCloseByCpIfExist(meta, pos, circle, order, 0, 1)) {
        return;
    }

    addToCpTree(false, false, circle, [-0.5, +0.5], meta, [pos, pos]); 
}


export { add1Prong }