package Web;

import java.io.IOException;
import java.net.InetSocketAddress;
import java.nio.ByteBuffer;
import java.nio.CharBuffer;
import java.nio.channels.SelectionKey;
import java.nio.channels.Selector;
import java.nio.channels.ServerSocketChannel;
import java.nio.channels.SocketChannel;
import java.nio.charset.Charset;

import java.util.Iterator;
import java.util.Set;
import java.util.logging.Level;
import java.util.logging.Logger;

/**
 * 服务器 负责分配静态文件服务器和应用服务
 *
 * @author Ma
 */
public class HttpServer {

 public static void init(int port) {
 try {
 //初始化数据库连接
 DB.connection();
 Selector selector = Selector.open();//创建selector
 ServerSocketChannel serverChannel = ServerSocketChannel.open();
 serverChannel.socket().bind(new InetSocketAddress(port));
 serverChannel.configureBlocking(false);
 serverChannel.register(selector, SelectionKey.OP_ACCEPT);//注册
 SocketChannel channel;
 try {
 while (true) {
 selector.select();
 Iterator<SelectionKey> iter = selector.selectedKeys().iterator();
 while (iter.hasNext()) {

 SelectionKey key = iter.next();
 iter.remove();

 Object attach = key.attachment();
 //如果有正在读取静态文件的标记就返回
 if (attach != null && attach.equals(0)) {
 continue;
 }


 //开始处理
 if (key.isAcceptable()) { // 接收请求 
 ServerSocketChannel server = (ServerSocketChannel) key.channel();
 channel = server.accept();
 //设置非阻塞模式 
 channel.configureBlocking(false);
 channel.register(selector, SelectionKey.OP_READ);
 } else if (key.isReadable()) { // 读信息 
 channel = (SocketChannel) key.channel();
 ByteBuffer clientBuffer = ByteBuffer.allocate(1024);
 int count = channel.read(clientBuffer);
 String receive = "";
 while (count > 0) {
 clientBuffer.flip();
 CharBuffer charBuffer = Charset.forName("UTF-8").decode(clientBuffer);
 String temp = charBuffer.toString();
 receive = receive + temp;
 clientBuffer.clear();
 count = channel.read(clientBuffer);
 channel.register(selector, SelectionKey.OP_WRITE);
 }

 key.attach(receive);
 clientBuffer.clear();
 } else if (key.isWritable()) { // 写事件 

 //开始处理事件
 //开始时间
 long startTime = System.currentTimeMillis();
 channel = (SocketChannel) key.channel();
 boolean accessStaticFile = false;//是不是访问的静态文件
 // 写事件 
 Request request = new Request((String) key.attachment());
 if (request.Path.equals("/favicon.ico") || request.Path.equals("robots.txt") || request.Path.toLowerCase().indexOf("/static") == 0) {
 //##处理
 //#说明是访问静态文件
 accessStaticFile = true;
 StaticFileServer staticFile = new StaticFileServer(request);
 if (staticFile.exists()) {
 staticFile.read(channel);
 key.attach(0);//这个标记是正在读取静态文件
 continue;//读取下一个循环
 } else {
 //如果不存在
 //当作非静态文件处理404 省事
 accessStaticFile = false;
 Response.setStatus(404);
 }

 }
 //访问的不是静态文件,或者静态文件不存在
 if (!accessStaticFile) {
 //###处理请求
 //获取客户端IP
 request.setRemoteIP(channel.socket().getLocalAddress().getHostName());
 //开始分配到Handler
 Allocation.init(request);

 //Handler结束

 if (Response.Content == null) {
 Response.setContent("未知错误造成,无返回实体!");
 Response.setStatus(500);
 }
 byte[] contentBytes = Response.Content.getBytes("UTF-8");
 //先设置实体长度
 Response.setContentLength(contentBytes.length);

 //然后获取header
 byte[] headerBytes = Response.getHeader().getBytes("UTF-8");
 ByteBuffer writerBuffer = ByteBuffer.allocate(headerBytes.length + contentBytes.length);
 writerBuffer.clear();
 writerBuffer.put(headerBytes);
 writerBuffer.put(contentBytes);
 writerBuffer.flip();
 while (writerBuffer.hasRemaining()) {
 channel.write(writerBuffer);
 }
 writerBuffer.clear();
 channel.close();
 //输出debug信息
 if (Options.DEBUG || Options.ParseLine) {
 System.out.println(Response.Status + " " + request.Header.get("Host") + request.Path + " " + (System.currentTimeMillis() - startTime) + "ms");
 }
 //完成响应,清理相应信息
 Response.finish();
 }

 }

 }
 }
 } finally {
 serverChannel.close();
 }
 } catch (IOException ex) {
 Logger.getLogger(HttpServer.class.getName()).log(Level.SEVERE, null, ex);
 }
 }

 /**
 * 设置URL
 *
 * @param path
 * @param handler
 */
 public static void setPATH(String path, Object handler) {
 Allocation.PATH.put(path, handler);
 }

 /**
 * 获取所有的Path
 *
 * @return
 */
 public static String[] getAllPath() {
 String[] pathArray = new String[Allocation.PATH.size()];
 Set set = Allocation.PATH.entrySet();
 Iterator iterator = set.iterator();
 int i = 0;
 while (iterator.hasNext()) {
 java.util.Map.Entry item = (java.util.Map.Entry) iterator.next();
 pathArray[i] = (String) item.getKey();
 i++;
 }
 return pathArray;
 }
}