/*******************************************************************************
 * 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;

import com.bstek.ureport.Utils;
import com.bstek.ureport.build.BindData;
import com.bstek.ureport.build.Context;
import com.bstek.ureport.exception.ReportException;
import com.bstek.ureport.expression.model.data.BindDataListExpressionData;
import com.bstek.ureport.expression.model.data.ExpressionData;
import com.bstek.ureport.expression.model.data.ObjectExpressionData;
import com.bstek.ureport.expression.model.data.ObjectListExpressionData;
import com.bstek.ureport.model.Cell;
import org.codehaus.jackson.map.ObjectMapper;

import java.util.HashMap;
import java.util.List;
import java.util.Map;

/**
 * @author Jacky.gao
 * @since 2017年1月3日
 */
public class JsonFunction implements Function {

    @Override
    public Object execute(List<ExpressionData<?>> dataList, Context context, Cell currentCell) {
        if (dataList.size() != 2) {
            return null;
        }
        String obj = buildData(dataList.get(0));
        String property = buildData(dataList.get(1));

        if (obj == null || property == null || obj.equals("") || property.equals("")) {
            return null;
        }
        ObjectMapper mapper = new ObjectMapper();
        try {
            Map<?, ?> map = mapper.readValue(obj, HashMap.class);
            return Utils.getProperty(map, property);
        } catch (Exception ex) {
            throw new ReportException(ex);
        }
    }

    private String buildData(ExpressionData<?> exprData) {
        String obj = null;
        if (exprData instanceof ObjectExpressionData) {
            ObjectExpressionData objData = (ObjectExpressionData) exprData;
            Object data = objData.getData();
            if (data != null) {
                obj = data.toString();
            }
        } else if (exprData instanceof ObjectListExpressionData) {
            ObjectListExpressionData listData = (ObjectListExpressionData) exprData;
            List<?> list = listData.getData();
            if (list.size() == 1) {
                Object data = list.get(0);
                if (data != null) {
                    obj = data.toString();
                }
            }
        } else if (exprData instanceof BindDataListExpressionData) {
            BindDataListExpressionData listData = (BindDataListExpressionData) exprData;
            List<BindData> list = listData.getData();
            if (list.size() == 1) {
                Object data = list.get(0).getValue();
                if (data != null) {
                    obj = data.toString();
                }
            }
        }
        return obj;
    }

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