/*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */
package be.vives.prog3.web;

import be.vives.prog3.control.BlogJpaController;
import be.vives.prog3.control.exceptions.NonexistentEntityException;
import be.vives.prog3.model.Blog;
import com.google.gson.Gson;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.List;
import javax.persistence.EntityManagerFactory;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 *
 * @author Jean-Pierre
 */
@WebServlet(name = "BlogServlet", urlPatterns = {"/BlogServlet"})
public class BlogServlet extends HttpServlet {

    private BlogJpaController blogJpaController;

    @Override
    public void init() throws ServletException {
        super.init(); //To change body of generated methods, choose Tools | Templates.
        ServletContext context = this.getServletContext();
        EntityManagerFactory emf =
                (EntityManagerFactory) context.getAttribute("EntityManagerFactory");
        blogJpaController = new BlogJpaController(emf);
    }

    /**
     * Als de request een parameter id heeft : deze Blog ophalen, anders alle Blogs
     * @param request
     * @param response
     * @throws ServletException
     * @throws IOException
     */
    protected void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        // 1. responseType instellen.
        response.setContentType("application/json;charset=UTF-8");

        // 2. Parameters uit de request halen (indien nodig)
        //Als de request een parameter id heeft : deze Blog ophalen, anders alle Blogs
        Integer id;
        try {
            id = Integer.parseInt(request.getParameter("id"));
        } catch (NumberFormatException e) {
            id = null;
        }

        Gson gson = new Gson();
        String jsonString;
        // 3. Instantie van het model ophalen en raadplegen.
        // 4. resultaat converteren naar een JSON String.
        if (id == null) {
            List<Blog> blogList = blogJpaController.findBlogEntities();
            jsonString = gson.toJson(blogList);
        } else {
            Blog blog = blogJpaController.findBlog(id);
            jsonString = gson.toJson(blog);
        }

        // 5. Output genereren
        try (PrintWriter out = response.getWriter()) {
            out.println(jsonString);
        }
    }

    //New Post
    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        // 1. responseType instellen.
        response.setContentType("application/json;charset=UTF-8");

        // 2. Parameters uit de request halen (indien nodig)
        String title   = request.getParameter("title");
        String content = request.getParameter("content");
        //Map<String, String[]> params = request.getParameterMap();

        // 3. Instantie van het model ophalen en raadplegen.
        Blog blog = new Blog(title, content);
        blogJpaController.create(blog);

        // 4. resultaat converteren naar een JSON String.
        Gson gson = new Gson();
        String jsonString = gson.toJson(blog);

        // 5. Output genereren
        try (PrintWriter out = response.getWriter()) {
            out.println(jsonString);
        }
    }

    @Override
    protected void doDelete(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        // 1. responseType instellen.
        resp.setContentType("application/json;charset=UTF-8");

        // 2. Parameters uit de request halen (indien nodig)
        Integer id;
        try {
            id = Integer.parseInt(req.getParameter("id"));
        } catch (NumberFormatException e) {
            id = -1;
        }

        // 3. Instantie van het model ophalen en raadplegen.
        int aantal = 1;
        try {
            blogJpaController.destroy(id);
        } catch (NonexistentEntityException ex) {
            aantal = 0;
        }

        // 4. resultaat converteren naar een JSON String.
        Gson gson = new Gson();
        String jsonString = gson.toJson(aantal);

        // 5. Output genereren
        try (PrintWriter out = resp.getWriter()) {
            out.println(jsonString);
        }
    }

    //Update Post
    @Override
    protected void doPut(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        // 1. responseType instellen.
        resp.setContentType("application/json;charset=UTF-8");

        // 2. Parameters uit de request halen (indien nodig)
        Integer id;
        try {
            id = Integer.parseInt(req.getParameter("id"));
        } catch (NumberFormatException e) {
            id = -1;
        }
        String title   = req.getParameter("title");
        String content = req.getParameter("content");

        // 3. Instantie van het model ophalen en raadplegen.
        Blog blog = new Blog(id, title, content);
        int aantal = 1;
        try {
            blogJpaController.edit(blog);
        } catch (Exception ex) {
            aantal = 0;
        }

        // 4. resultaat converteren naar een JSON String.
        Gson gson = new Gson();
        String jsonString = gson.toJson(aantal);

        // 5. Output genereren
        try (PrintWriter out = resp.getWriter()) {
            out.println(jsonString);
        }
    }

    /**
     * Returns a short description of the servlet.
     *
     * @return a String containing servlet description
     */
    @Override
    public String getServletInfo() {
        return "Short description";
    }// </editor-fold>


}