package ECC;

import java.math.BigInteger;

public class Point {

    private BigInteger x;
    private BigInteger y;
    private boolean isInfinity;
    
    private static Point INFINITY;

    public Point(BigInteger x, BigInteger y) {
        this.x = x;
        this.y = y;
        isInfinity = false;
    }
    public Point(Point p) {
        this.x = p.getX();
        this.y = p.getY();
        isInfinity = p.isInfinity(); 
    }
    public Point(long x, long y) {
        this( BigInteger.valueOf(x), BigInteger.valueOf(y));
    }
    public Point() {
        this.x = this.y = BigInteger.ZERO;
        isInfinity = true;
    }
    public static Point make(int[] array){
        String x, y;
        x = y = "";
        for (int i = 0; i < 2 * ECC.PAD; i++) {
            if(i<ECC.PAD)
                x += array[i];
            else y += array[i];
        }
        return new Point(Integer.parseInt(x, 2), Integer.parseInt(y, 2));
    }

    public BigInteger getX() {
        return x;
    }

    public BigInteger getY() {
        return y;
    }

    public boolean isInfinity() {
        return isInfinity;
    }
    
    public Point negate() {
        if (isInfinity()) {
            return getInfinity();
        }
        return new Point(x, y.negate());
    }
    
    public static Point getInfinity() {
        if(INFINITY == null)
            INFINITY = new Point();
        return INFINITY;
    }
    
    public boolean equals(Object other) {
        if (this == other) {
            return true;
        }
        if (other instanceof Point) {
            if (this.x != null) {
                Point otherPoint = (Point)other;
                // no need to check for null in this case
                return this.x.equals(otherPoint.x) &&
                       this.y.equals(otherPoint.y);
            } else {
                return other == getInfinity();
            }
        }
        return false;
    }

    @Override
    public String toString() {
        if (isInfinity()) {
            return "INFINITY";
        } else {
            return "(" + x.toString() + ", " + y.toString() + ")";
        }
    }
    
    @Override
    public int hashCode(){        
        if (this.isInfinity) {
            return x.hashCode() * 31 + x.hashCode();
        }
        return 11;
    }
}