/*******************************************************************************
 * Copyright 2017 Bstek
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not
 * use this file except in compliance with the License.  You may obtain a copy
 * of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
 * License for the specific language governing permissions and limitations under
 * the License.
 ******************************************************************************/
package com.bstek.ureport.expression.function.math;

import com.bstek.ureport.build.Context;
import com.bstek.ureport.expression.model.data.ExpressionData;
import com.bstek.ureport.model.Cell;

import java.math.BigDecimal;
import java.util.List;

/**
 * @author Jacky.gao
 * @since 2017年1月23日
 */
public class ChnFunction extends MathFunction {
    private static final String[] CN_UPPER_NUMBER = {"零", "壹", "贰", "叁", "肆", "伍", "陆", "柒", "捌", "玖"};
    private static final String[] CN_UPPER_UNIT = {"", "", "点", "拾", "佰", "仟", "万", "拾", "佰", "仟", "亿", "拾", "佰", "仟", "兆", "拾", "佰", "仟"};
    private static final String CN_NEGATIVE = "负";
    private static final int NUMBER_PRECISION = 2;
    private static final String CN_ZEOR = "零";

    @Override
    public Object execute(List<ExpressionData<?>> dataList, Context context, Cell currentCell) {
        BigDecimal data = buildBigDecimal(dataList);
        return numberToChn(data);
    }

    @Override
    public String name() {
        return "chn";
    }

    public static void main(String[] args) {
        BigDecimal numberData = new BigDecimal("30010.12");
        String chn = numberToChn(numberData);
        System.out.println(chn);
    }

    private static String numberToChn(BigDecimal numberData) {
        StringBuilder sb = new StringBuilder();
        int signum = numberData.signum();
        if (signum == 0) {
            return CN_ZEOR;
        }
        long number = numberData.movePointRight(NUMBER_PRECISION).setScale(0, BigDecimal.ROUND_HALF_UP).abs().longValue();
        long scale = number % 100;
        int numUnit;
        int numIndex = 0;
        boolean getZero = false;
        if (!(scale > 0)) {
            numIndex = 2;
            number = number / 100;
            getZero = true;
        }
        if ((scale > 0) && (!(scale % 10 > 0))) {
            numIndex = 1;
            number = number / 10;
            getZero = true;
        }
        int zeroSize = 0;
        while (number > 0) {
            numUnit = (int) (number % 10);
            if (numUnit > 0) {
                if ((numIndex == 9) && (zeroSize >= 3)) {
                    sb.insert(0, CN_UPPER_UNIT[6]);
                }
                if ((numIndex == 13) && (zeroSize >= 3)) {
                    sb.insert(0, CN_UPPER_UNIT[10]);
                }
                String unit = buildPoint(numIndex, sb);
                sb.insert(0, unit);
                sb.insert(0, CN_UPPER_NUMBER[numUnit]);
                getZero = false;
                zeroSize = 0;
            } else {
                ++zeroSize;
                if (!(getZero)) {
                    String unit = CN_UPPER_UNIT[numIndex];
                    if (!unit.equals("点")) {
                        sb.insert(0, CN_UPPER_NUMBER[numUnit]);
                    }
                }
                if (numIndex == 2) {
                    String unit = buildPoint(numIndex, sb);
                    sb.insert(0, unit);
                } else if (((numIndex - 2) % 4 == 0) && (number % 1000 > 0)) {
                    sb.insert(0, CN_UPPER_UNIT[numIndex]);
                }
                getZero = true;
            }
            number = number / 10;
            ++numIndex;
        }
        if (signum == -1) {
            sb.insert(0, CN_NEGATIVE);
        }
        return sb.toString();
    }

    private static String buildPoint(int numIndex, StringBuilder sb) {
        String unit = CN_UPPER_UNIT[numIndex];
        if (unit.equals("点")) {
            if (sb.length() > 0) {
                return unit;
            }
        } else {
            return unit;
        }
        return "";
    }
}
