/*
 * #%L
 * BroadleafCommerce Common Libraries
 * %%
 * Copyright (C) 2009 - 2014 Broadleaf Commerce
 * %%
 * 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.
 * #L%
 */
package org.broadleafcommerce.common.web;

import com.fasterxml.jackson.databind.ObjectMapper;

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

import javax.servlet.http.HttpServletResponse;


/**
 * Used when a controller typically returns a String that represents a view path but would like to return a
 * JSON response in other scenarios, such as an error case.
 * 
 * Example Usage:
 * 
 * return new JsonResponse(response)
 *     .with("status", "ok")
 *     .with("shouldRefresh", true)
 *     .done();
 * 
 * @author Andre Azzolini (apazzolini)
 */
public class JsonResponse {
    
    protected Map<String, Object> map = new HashMap<String, Object>();
    protected HttpServletResponse response;
    
    public JsonResponse(HttpServletResponse response) {
        this.response = response;
    }
    
    public JsonResponse with(String key, Object value) {
        map.put(key, value);
        return this;
    }
    
    public String done() {
        response.setHeader("Content-Type", "application/json");
        try {
            new ObjectMapper().writeValue(response.getWriter(), map);
        } catch (Exception e) {
            throw new RuntimeException("Could not serialize JSON", e);
        }
        return null;
    }

}