/*
  Mediazentrale - Personal Media Center
  Copyright (C) 2021  Ulrich Hilger

  This program is free software: you can redistribute it and/or modify
  it under the terms of the GNU Affero General Public License as
  published by the Free Software Foundation, either version 3 of the
  License, or (at your option) any later version.

  This program is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU Affero General Public License for more details.

  You should have received a copy of the GNU Affero General Public License
  along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */
package de.uhilger.mediaz.api;

import com.sun.net.httpserver.HttpExchange;
import com.sun.net.httpserver.HttpHandler;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.util.logging.Logger;


/**
 *
 * @author Ulrich Hilger
 * @version 1, 8.4.2021
 */
public abstract class AbstractHandler extends JsonHelper implements HttpHandler {
  
  private static final Logger logger = Logger.getLogger(AbstractHandler.class.getName());

  /** Name der HTTP Methode GET */
  public static final String HTTP_GET = "GET";
  
  /** Name der HTTP Methode PUT */
  public static final String HTTP_PUT = "PUT";
  
  /** Name der HTTP Methode POST */
  public static final String HTTP_POST = "POST";
  
  /** Name der HTTP Methode DELETE */
  public static final String HTTP_DELETE = "DELETE";
  
  public static final int RTC_OK = 200;
  public static final int RTC_NOT_FOUND = 404;
  
  protected int returnCode;

  public AbstractHandler() {
    this.returnCode = RTC_OK;
  }
  
  @Override
  public void handle(HttpExchange e) throws IOException {
    String method = e.getRequestMethod();
    String response = "";
    switch(method) {
      case HTTP_GET:
        String json = get(e);
        if(json != null) {
          response = json;
        } else {
          response = "nicht gefunden";
          returnCode = RTC_NOT_FOUND;
        }
        break;
        
      case HTTP_PUT:
        response = put(e);
        break;
        
      case HTTP_POST:
        response = post(e);
        break;
        
      case HTTP_DELETE:
        boolean geloescht = delete(e);
        if(geloescht) {
          response = "geloescht";
        } else {
          response = "nicht geloescht";
        }
        break;
    }
    logger.info(response);
    e.sendResponseHeaders(getReturnCode(), response.length());
    OutputStream os = e.getResponseBody();
    os.write(response.getBytes());
    os.close();        
  }
  
  protected void setReturnCode(int code) {
    this.returnCode = code;
  }
  
  protected int getReturnCode() {
    return returnCode;
  }
  
  protected String bodyLesen(HttpExchange e) throws IOException {
    InputStream is = e.getRequestBody();
    BufferedReader r = new BufferedReader(new InputStreamReader(is));
    StringBuilder sb = new StringBuilder();
    String line = r.readLine();
    while(line != null) {
      sb.append(line);
      line = r.readLine();
    }
    r.close();
    String json = sb.toString();
    return json;
  }

  protected String put(HttpExchange e) throws IOException {
    setReturnCode(RTC_NOT_FOUND);
    return "nicht unterstuetzt";
  }

  protected String post(HttpExchange e) {
    setReturnCode(RTC_NOT_FOUND);
    return "nicht unterstuetzt";
  }

  protected boolean delete(HttpExchange e) {
    setReturnCode(RTC_NOT_FOUND);
    return false;
  }
  
  
  protected abstract String get(HttpExchange e);
  /*
  protected abstract String put(HttpExchange e) throws IOException;
  protected abstract String post(HttpExchange e);
  protected abstract boolean delete(HttpExchange e);
  */
  
}