package com.dsh.utils;


import org.apache.commons.beanutils.BeanUtils;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.ss.usermodel.Sheet;
import org.apache.poi.ss.usermodel.Workbook;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;

import java.io.IOException;
import java.io.InputStream;
import java.util.*;

/**
 * Created by Roy.xiao on 2017/7/20.
 */
public class ExcelParser {

    /**
     * 数据源
     */
    private InputStream in;
    /**
     * 扩展名
     */
    private String ext;

    /**
     * 常量： 扩展名
     */
    public static final String EXT_XLSX = "xlsx";
    public static final String EXT_XLS = "xls";

    /**
     * 解析方式
     */
    private int SIMPLE_DATASET = 0;
    private int SPECIFIC_DATASET = 1;

    public ExcelParser(InputStream inputStream, String ext) {
        this.in = inputStream;
        this.ext = ext;
    }

    /**
     * 返还简单数据集
     * @return
     */
    public List<Map<String, Object>> dataset() {
        return parseParams(SIMPLE_DATASET);
    }

    /**
     * 返还指定类型集合
     * @param tClass
     * @param <T>
     * @return 返还指定类型集合
     */
    public <T>List<T> specificList(Class<T> tClass) {
        List<T> targetList = new ArrayList<T>();
        List<Map<String, Object>> speDatas = parseParams(SPECIFIC_DATASET);
        for (Map<String, Object> map: speDatas) {
            T obj = null;
            try {
                obj = tClass.newInstance();
            } catch (Exception e) {
                throw new RuntimeException(e);
            }
            Set<Map.Entry<String, Object>> entrySet =map.entrySet();
            Iterator it = entrySet.iterator();
            while (it.hasNext()) {
                Map.Entry<String, Object> entry = (Map.Entry<String, Object>) it.next();
                try {
                    BeanUtils.setProperty(obj, entry.getKey(), entry.getValue());
                }catch (Exception e) {
                    throw new RuntimeException(e);
                }
            }
            targetList.add(obj);
        }
        return targetList;
    }

    /**
     * 模板解析
     * @param type
     * @return
     */
    private List<Map<String, Object>> parseParams(int type) {
        List<Map<String, Object>> dataset = new LinkedList<Map<String, Object>>();
        Workbook workbook = null;

        try {
            if (ext.equals(EXT_XLS)) {
                workbook = new HSSFWorkbook(in);
            } else {
                workbook = new XSSFWorkbook(in);
            }
        } catch (IOException e) {
            throw new RuntimeException(e);
        }
        Iterator<Sheet> sheetIterator = workbook.sheetIterator();
        List<String> titleGroup = new ArrayList<String>();

        boolean isFirstRowDes = true;
        boolean isFirstRowTitle = true;

        while (sheetIterator.hasNext()) {
            Sheet sheet = sheetIterator.next();
            Iterator<Row> rowIterator = sheet.rowIterator();

            while (rowIterator.hasNext()) {
                Row row = rowIterator.next();
                if (row == null) {
                    continue;
                }
                if (isFirstRowDes){
                    isFirstRowDes = false;
                    continue;
                }
                Iterator<Cell> cellIterator = row.cellIterator();
                int cellNum = 0;
                Map<String, Object> cells = new TreeMap<String, Object>();
                while (cellIterator.hasNext()) {
                    Cell cell = cellIterator.next();
//                    if (isFirstRowTitle) {
//                        titleGroup.add(cell.getStringCellValue());
//                        continue;
//                    }
                    String dataKey = null;
                    if (type == SIMPLE_DATASET) {
                        dataKey = String.valueOf(cell.getColumnIndex());
                    } else {
                        dataKey = titleGroup.get(cellNum);
                    }
                    switch (cell.getCellType()) {
                        case Cell.CELL_TYPE_BOOLEAN:
                            cells.put(dataKey, cell.getBooleanCellValue());
                            break;
                        case Cell.CELL_TYPE_NUMERIC:
                            cells.put(dataKey, cell.getNumericCellValue());
                            break;
                        case Cell.CELL_TYPE_STRING:
                            cells.put(dataKey, cell.getStringCellValue());
                            break;
                        case Cell.CELL_TYPE_BLANK:
                            cells.put(dataKey, "");
                            break;
                        default:
                            cells.put(dataKey, "");
                            break;
                    }
                    cellNum ++;
                }
//                if (!isFirstRowTitle) {
                    dataset.add(cells);
//                }
                if (isFirstRowTitle) {
                    if (titleGroup.size() != 0) {
                        isFirstRowTitle = false;
                    }
                }
            }
        }
        return dataset;
    }

}