import { evalCertified } from "./double/eval-certified.js";
import { eHorner } from "./expansion/e-horner.js";
import { eEstimate } from 'big-float-ts';


/**
 * Returns the result of evaluating the given polynomial (with double-double
 * precision coefficients) at the given value, where the coefficient-wise error 
 * is also given. 
 * 
 * * **the sign of the returned result is guaranteed to be correct**
 * * the evaluation is done adaptively, i.e. if the evaluation cannot be done
 * accurately enough then an exact precision polynomial is requested
 * 
 * @param p a polynomial given as an array with each consecutive element of
 * the array having more accurate coefficients than the previous (by adding 
 * consecutive double precision coefficients to prior coefficients)
 * @param pE a coefficientwise error bound
 * @param x the point of evaluation
 * @param psExact an object holding the exact polynomial and all its exact 
 * derivatives - this object may be modified!
 * @param getPsExact a function to retrieve the exact polynomial and all its 
 * exact derivatives
 * @param diffCount the number of differentiations done up to this point
 * 
 * @internal
 */
function evalAdaptive(
        p: number[][], 
        pE: number[], 
        x: number, 
        getPolyExact: () => number[][]): number {

    const r = evalCertified(p, x, pE, 4);
    if (r !== 0) {
        return r;
    }

    // condition number is too high - request higher precision

    return eEstimate(eHorner(getPolyExact(), x));
}


export { evalAdaptive }