/*
 *  Copyright 2015 the original author or authors. 
 *  @https://github.com/scouter-project/scouter
 *
 *  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 scouter.server.netio.service;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Set;
import scouter.io.DataInputX;
import scouter.io.DataOutputX;
import scouter.server.Configure;
import scouter.server.Logger;
import scouter.server.netio.service.anotation.ServiceHandler;
import scouter.util.scan.Scanner;
public class ServiceHandlingProxy {
	protected static HashMap<String, Invocation> handlers = new HashMap<String, Invocation>();
	protected static class Invocation {
		Object object;
		Method method;
		public Invocation(Object object, Method method) {
			this.object = object;
			this.method = method;
		}
		public void exec(DataInputX in, DataOutputX out, boolean login) {
			try {
				method.invoke(object, new Object[] { in, out, login });
			} catch (InvocationTargetException t) {
				if (t.getCause() != null) {
					t.getCause().printStackTrace();
				} else {
					t.printStackTrace();
				}
			} catch (Exception e) {
				Logger.println("S777", 10, "Service Exception", e);
				e.printStackTrace();
			}
		}
		@Override
		public String toString() {
			return object.getClass().getName() + "." + method.getName();
		}
	}
	public static void load() {
		String pkg = Scanner.cutOutLast(ServiceHandlingProxy.class.getName(), ".");
		Set<String> classes = new Scanner(pkg).process(ServiceHandlingProxy.class.getClassLoader());
		Set<String> custom = new Scanner(System.getProperty("scouter.handler")).process();
		classes.addAll(custom);
		Iterator<String> itr = classes.iterator();
		while (itr.hasNext()) {
			try {
				Class c = Class.forName(itr.next());
				if (Modifier.isPublic(c.getModifiers()) == false) {
					continue;
				}
				try {
					Method[] m = c.getDeclaredMethods();
					for (int i = 0; i < m.length; i++) {
						ServiceHandler mapAn = (ServiceHandler) m[i].getAnnotation(ServiceHandler.class);
						if (mapAn == null)
							continue;
						String key = mapAn.value();
						Invocation news = new Invocation(c.newInstance(), m[i]);
						Invocation olds = handlers.get(key);
						if (olds != null) {
							Logger.println("Warning duplicated Handler key=" + key + " old=" + olds + " new=" + news);
						} else {
							if (Configure.getInstance().log_service_handler_list) {
								Logger.println("ServiceHandler " + key + "=>" + news);
							}
						}
						handlers.put(key, news);
					}
				} catch (Exception x) {
					x.printStackTrace();
				}
			} catch (Exception e) {
				e.printStackTrace();
			}
		}
	}
	public static void process(String cmd, DataInputX in, DataOutputX out, boolean login) {
		Invocation handler = handlers.get(cmd);
		if (handler != null) {
			handler.exec(in, out, login);
		} else {
			// Logger.println("no handler  " + cmd);
			throw new RuntimeException("no handler  cmd=" + cmd);
		}
	}
	public static void main(String[] args) {
		load();
	}
}