export class BSpline {
    points: any[] = [];
    degree: any;
    dimension: any;
    baseFunc: any;
    baseFuncRangeInt: number = 0; // INIT??


    constructor(points: any, degree: any, copy?: any) {
        if (copy) {
            this.points = []
            for (var i = 0; i < points.length; i++) {
                this.points.push(points[i]);
            }
        } else {
            this.points = points;
        }
        this.degree = degree;
        this.dimension = points[0].length;
        if (degree == 2) {
            this.baseFunc = this.basisDeg2;
            this.baseFuncRangeInt = 2;
        } else if (degree == 3) {
            this.baseFunc = this.basisDeg3;
            this.baseFuncRangeInt = 2;
        } else if (degree == 4) {
            this.baseFunc = this.basisDeg4;
            this.baseFuncRangeInt = 3;
        } else if (degree == 5) {
            this.baseFunc = this.basisDeg5;
            this.baseFuncRangeInt = 3;
        }
    }

    //BSpline.prototype.seqAt = function(dim: any): any{
    seqAt(dim: any): any {
        var points: any = this.points;
        var margin: any = this.degree + 1;
        return function (n: any) {
            if (n < margin) {
                return points[0][dim];
            } else if (points.length + margin <= n) {
                return points[points.length - 1][dim];
            } else {
                return points[n - margin][dim];
            }
        };
    };

    //BSpline.prototype.basisDeg2 = function(x: any): number{
    basisDeg2(x: any): number {
        if (-0.5 <= x && x < 0.5) {
            return 0.75 - x * x;
        } else if (0.5 <= x && x <= 1.5) {
            return 1.125 + (-1.5 + x / 2.0) * x;
        } else if (-1.5 <= x && x < -0.5) {
            return 1.125 + (1.5 + x / 2.0) * x;
        } else {
            return 0;
        }
    };

    //BSpline.prototype.basisDeg3 = function(x: any): number{
    basisDeg3(x: any): number {
        if (-1 <= x && x < 0) {
            return 2.0 / 3.0 + (-1.0 - x / 2.0) * x * x;
        } else if (1 <= x && x <= 2) {
            return 4.0 / 3.0 + x * (-2.0 + (1.0 - x / 6.0) * x);
        } else if (-2 <= x && x < -1) {
            return 4.0 / 3.0 + x * (2.0 + (1.0 + x / 6.0) * x);
        } else if (0 <= x && x < 1) {
            return 2.0 / 3.0 + (-1.0 + x / 2.0) * x * x;
        } else {
            return 0;
        }
    };

    //BSpline.prototype.basisDeg4 = function(x: any): number{
    basisDeg4(x: any): number {
        if (-1.5 <= x && x < -0.5) {
            return 55.0 / 96.0 + x * (-(5.0 / 24.0) + x * (-(5.0 / 4.0) + (-(5.0 / 6.0) - x / 6.0) * x));
        } else if (0.5 <= x && x < 1.5) {
            return 55.0 / 96.0 + x * (5.0 / 24.0 + x * (-(5.0 / 4.0) + (5.0 / 6.0 - x / 6.0) * x));
        } else if (1.5 <= x && x <= 2.5) {
            return 625.0 / 384.0 + x * (-(125.0 / 48.0) + x * (25.0 / 16.0 + (-(5.0 / 12.0) + x / 24.0) * x));
        } else if (-2.5 <= x && x <= -1.5) {
            return 625.0 / 384.0 + x * (125.0 / 48.0 + x * (25.0 / 16.0 + (5.0 / 12.0 + x / 24.0) * x));
        } else if (-1.5 <= x && x < 1.5) {
            return 115.0 / 192.0 + x * x * (-(5.0 / 8.0) + x * x / 4.0);
        } else {
            return 0;
        }
    };

    //BSpline.prototype.basisDeg5 = function(x: any): number{
    basisDeg5(x: any): number {
        if (-2 <= x && x < -1) {
            return 17.0 / 40.0 + x * (-(5.0 / 8.0) + x * (-(7.0 / 4.0) + x * (-(5.0 / 4.0) + (-(3.0 / 8.0) - x / 24.0) * x)));
        } else if (0 <= x && x < 1) {
            return 11.0 / 20.0 + x * x * (-(1.0 / 2.0) + (1.0 / 4.0 - x / 12.0) * x * x);
        } else if (2 <= x && x <= 3) {
            return 81.0 / 40.0 + x * (-(27.0 / 8.0) + x * (9.0 / 4.0 + x * (-(3.0 / 4.0) + (1.0 / 8.0 - x / 120.0) * x)));
        } else if (-3 <= x && x < -2) {
            return 81.0 / 40.0 + x * (27.0 / 8.0 + x * (9.0 / 4.0 + x * (3.0 / 4.0 + (1.0 / 8.0 + x / 120.0) * x)));
        } else if (1 <= x && x < 2) {
            return 17.0 / 40.0 + x * (5.0 / 8.0 + x * (-(7.0 / 4.0) + x * (5.0 / 4.0 + (-(3.0 / 8.0) + x / 24.0) * x)));
        } else if (-1 <= x && x < 0) {
            return 11.0 / 20.0 + x * x * (-(1.0 / 2.0) + (1.0 / 4.0 + x / 12.0) * x * x);
        } else {
            return 0;
        }
    };

    //BSpline.prototype.getInterpol = function(seq: any, t: any): number{
    getInterpol(seq: any, t: any): number {
        var f: any = this.baseFunc;
        var rangeInt: any = this.baseFuncRangeInt;
        var tInt: number = Math.floor(t);
        var result: number = 0;
        for (var i = tInt - rangeInt; i <= tInt + rangeInt; i++) {
            result += seq(i) * f(t - i);
        }
        return result;
    };

    //BSpline.prototype.calcAt = function(t: any): any{
    calcAt(t: any): any {
        t = t * ((this.degree + 1) * 2 + this.points.length);//t must be in [0,1]
        if (this.dimension == 2) {
            return [this.getInterpol(this.seqAt(0), t), this.getInterpol(this.seqAt(1), t)];
        } else if (this.dimension == 3) {
            return [this.getInterpol(this.seqAt(0), t), this.getInterpol(this.seqAt(1), t), this.getInterpol(this.seqAt(2), t)];
        } else {
            var res = [];
            for (var i = 0; i < this.dimension; i++) {
                res.push(this.getInterpol(this.seqAt(i), t));
            }
            return res;
        }
    };
}

/*
var BSpline = function(points: any, degree: any, copy: any){
    if(copy){
        this.points = []
        for(var i = 0;i<points.length;i++){
            this.points.push(points[i]);
        }
    }else{
        this.points = points;
    }
    this.degree = degree;
    this.dimension = points[0].length;
    if(degree == 2){
        this.baseFunc = this.basisDeg2;
        this.baseFuncRangeInt = 2;
    }else if(degree == 3){
        this.baseFunc = this.basisDeg3;
        this.baseFuncRangeInt = 2;
    }else if(degree == 4){
        this.baseFunc = this.basisDeg4;
        this.baseFuncRangeInt = 3;
    }else if(degree == 5){
        this.baseFunc = this.basisDeg5;
        this.baseFuncRangeInt = 3;
    }
};
*/