package com.zy.common.utils;

import java.math.BigDecimal;
import java.math.RoundingMode;

public class Arith {
    public static double add(int dot, Number... numbers) {
        return getAirth(dot, Arith.ArithType.ADD.getValue(), numbers);
    }

    public static double subtract(int dot, Number... numbers) {
        return getAirth(dot, Arith.ArithType.SUBTRACT.getValue(), numbers);
    }

    public static double multiplys(int dot, Number... numbers) {
        return getAirth(dot, Arith.ArithType.MULTIPLY.getValue(), numbers);
    }

    public static double divides(int dot, Number... numbers) {
        return getAirth(dot, Arith.ArithType.DIVIDE.getValue(), numbers);
    }

    public static int percentage(Number... numbers) {
        return (int) (divides(2, numbers) * (double) 100.0F);
    }

    public static double remainder(Number... numbers) {
        return (new BigDecimal(numbers[0].toString())).remainder(new BigDecimal(String.valueOf(numbers[1]))).doubleValue();
    }

    private static double getAirth(int dot, int arithType, Number... numbers) {
        if (numbers != null && numbers.length != 0) {
            BigDecimal bigDecimal = new BigDecimal(numbers[0].toString());

            for (int i = 1; i < numbers.length; ++i) {
                switch (arithType) {
                    case 0:
                        bigDecimal = bigDecimal.add(new BigDecimal(String.valueOf(numbers[i])));
                        break;
                    case 1:
                        bigDecimal = bigDecimal.divide(new BigDecimal(String.valueOf(numbers[i])), dot, RoundingMode.HALF_UP);
                        break;
                    case 2:
                        bigDecimal = bigDecimal.subtract(new BigDecimal(String.valueOf(numbers[i])));
                        break;
                    case 3:
                        bigDecimal = bigDecimal.multiply(new BigDecimal(String.valueOf(numbers[i])));
                        break;
                    default:
                        return (double) 0.0F;
                }
            }

            return bigDecimal.setScale(dot, RoundingMode.HALF_UP).doubleValue();
        } else {
            return (double) 0.0F;
        }
    }

    private static enum ArithType {
        ADD("add", 0),
        DIVIDE("divide", 1),
        SUBTRACT("subtract", 2),
        MULTIPLY("multiply", 3);

        private String key;
        private int value;

        private ArithType(String key, int value) {
            this.key = key;
            this.value = value;
        }

        public int getValue() {
            return this.value;
        }
    }
}