package org.apidesign.apifest08.currency;

public final class Rate {

    private double rate;

    public Rate(int amountA, int amountB) {

        rate = amountA / (double)amountB;

        if (rate <= 0) {

            throw new IllegalArgumentException("Exchange rate must be positive.");

        }

    }

    public Rate(double amountA, double amountB) {

        rate = amountA / amountB;

        if (rate <= 0) {

            throw new IllegalArgumentException("Exchange rate must be positive.");

        }

    }

    public Rate(double rate) {

        this.rate = rate;

        if (this.rate <= 0) {

            throw new IllegalArgumentException("Exchange rate must be positive.");

        }

    }

    public double convertAtoB(int a) {

        return a / rate;

    }

    public double convertAtoB(double a) {

        return a / rate;

    }

    public double convertBtoA(int b) {

        return b * rate;

    }

    public double convertBtoA(double b) {

        return b * rate;

    }

    @Override

    public boolean equals(Object obj) {

        if (obj == null) {

            return false;

        }

        if (getClass() != obj.getClass()) {

            return false;

        }

        final Rate other = (Rate) obj;

        return true;

    }

    @Override

    public int hashCode() {

        int hash = 5;

        return hash;

    }

    @Override

    public String toString() {

        return ""+rate;

    }

}