package Web;

import java.nio.channels.SocketChannel;

import java.util.logging.Level;

import java.util.logging.Logger;

import java.io.IOException;

import java.nio.ByteBuffer;

import java.nio.channels.AsynchronousFileChannel;

import java.nio.channels.CompletionHandler;

import java.nio.file.Files;

import java.nio.file.Path;

import java.nio.file.Paths;

import java.nio.file.attribute.BasicFileAttributeView;

import java.nio.file.attribute.BasicFileAttributes;

import java.util.concurrent.TimeUnit;

/**

* 静态文件服务器

*

* @author Ma

*/

public class StaticFileServer {

public Request request;

public int size;

public ByteBuffer byteBuffer;

public SocketChannel socketChannel;

public Path filePath;

public String ExName;//扩展名字

/**

* 初始化一些东西

*

* @param request

*/

public StaticFileServer(Request request) {

this.request = request;

String path = Options.StaticPath + this.request.Path.substring(8);

this.filePath = Paths.get(path);

//设置扩展名

int index = this.request.Path.lastIndexOf(".");

this.ExName = this.request.Path.substring(index + 1);

}

/**

* 检测文件是否存在

*

* @return

*/

public boolean exists() {

return Files.exists(filePath);

}

/**

* 检查文件是否需要更新还是304状态吗

*

* @return

*/

public boolean update() {

try {

int lastTime = (int) Files.getLastModifiedTime(filePath).to(TimeUnit.SECONDS);//获取最后修改的时间戳

Object paramTime = this.request.Header.get("If-Modified-Since");

if ((paramTime != null) && (Integer.parseInt((String) paramTime) <= lastTime)) {

//处理304

Response.setStatus(304);

Response.setContentType(Response.findContentType(this.ExName));

Response.header("Last-Modified: " + lastTime);

Response.header("Cache-Control:public, max-age=2592000");

byte[] headerBytes = Response.getHeader().getBytes();

ByteBuffer writerBuffer = ByteBuffer.allocate(headerBytes.length);

writerBuffer.clear();

writerBuffer.put(headerBytes);

writerBuffer.flip();

while (writerBuffer.hasRemaining()) {

this.socketChannel.write(writerBuffer);

}

writerBuffer.clear();

this.socketChannel.close();

//输出debug信息

if (Options.DEBUG || Options.ParseLine) {

System.out.println(Response.Status + " " + this.request.Header.get("Host") + this.request.Path);

}

Response.finish();//清理信息

return false;

}

} catch (IOException ex) {

Logger.getLogger(StaticFileServer.class.getName()).log(Level.SEVERE, null, ex);

}

return true;

}

public void read(SocketChannel socketChannel) {

this.socketChannel = socketChannel;

//处理304

if (this.update()) {

//输出debug信息

if (Options.DEBUG || Options.ParseLine) {

System.out.println("Static File" + " " + this.request.Header.get("Host") + this.request.Path);

}

//处理200

BasicFileAttributeView basicView = Files.getFileAttributeView(this.filePath, BasicFileAttributeView.class);

try {

BasicFileAttributes basicAttrs = basicView.readAttributes();

long size = basicAttrs.size();

if (size > 2097152) {

//说明文件大于2M

}

this.size = (int) size;

int lastTime = (int) Files.getLastModifiedTime(filePath).to(TimeUnit.SECONDS);//获取最后修改的时间戳

this.byteBuffer = ByteBuffer.allocate((int) size);//申请缓存空间

//开始获取通道，读取文件

AsynchronousFileChannel afc = AsynchronousFileChannel.open(this.filePath);

afc.read(byteBuffer, 0, lastTime, new CompletionHandlerImpl(afc));

} catch (IOException ex) {

//处理500错误

Logger.getLogger(StaticFileServer.class.getName()).log(Level.SEVERE, null, ex);

}

}

}

/**

* 成员类 处理文件完成后的操作

*/

private class CompletionHandlerImpl implements CompletionHandler<Integer, Object> {

AsynchronousFileChannel afc;

public CompletionHandlerImpl(AsynchronousFileChannel afc) {

this.afc = afc;

}

/**

* 处理成功的操作

*

* @param result

* @param attachment

*/

@Override

public void completed(Integer result, Object attachment) {

Integer lastModifyInteger = (Integer) attachment;

int lastModify = lastModifyInteger.intValue();

//Header不能使用Response

String header = "HTTP/1.1 200 OK\r\n"

+ "Content-type: " + Response.findContentType(StaticFileServer.this.ExName) + ";\r\n"

+ "Content-ength: " + StaticFileServer.this.size + "\r\n"

+ "Last-Modified: " + lastModify + "\r\n"

+ "Cache-Control:public, max-age=2592000 \r\n"

+ "Server: " + Response.Server + "\r\n\r\n";

byte[] headerBytes = header.getBytes();

byte[] contentBytes = StaticFileServer.this.byteBuffer.array();

ByteBuffer writerBuffer = ByteBuffer.allocate(headerBytes.length + contentBytes.length);

writerBuffer.clear();

writerBuffer.put(headerBytes);

writerBuffer.put(contentBytes);

writerBuffer.flip();

try {

while (writerBuffer.hasRemaining()) {

StaticFileServer.this.socketChannel.write(writerBuffer);

}

writerBuffer.clear();

StaticFileServer.this.socketChannel.close();

this.afc.close();

} catch (IOException ex) {

Logger.getLogger(StaticFileServer.class.getName()).log(Level.SEVERE, null, ex);

}

}

/**

* 处理失败的操作

*

* @param exc

* @param attachment

*/

@Override

public void failed(Throwable exc, Object attachment) {

System.out.println(exc.getCause());

//@todo 处理500错误

try {

StaticFileServer.this.socketChannel.close();

this.afc.close();

} catch (IOException ex) {

Logger.getLogger(StaticFileServer.class.getName()).log(Level.SEVERE, null, ex);

}

}

}

}