package com.fr.plugin;


import com.fr.log.FineLoggerFactory;
import com.fr.log.FineLoggerProvider;

import javax.servlet.ReadListener;
import javax.servlet.ServletInputStream;
import javax.servlet.ServletRequest;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;
import java.io.*;
import java.nio.charset.Charset;
import java.nio.charset.StandardCharsets;

/**
 * @author 01
 * @program wrapper-demo
 * @description 包装HttpServletRequest，目的是让其输入流可重复读
 * @create 2018-12-24 20:48
 * @since 1.0
 **/
public class RequestWrapper extends HttpServletRequestWrapper {
    FineLoggerProvider log = FineLoggerFactory.getLogger();
    /**
     * 存储body数据的容器
     */
    private byte[] body;

    public RequestWrapper(HttpServletRequest request) {
        super(request);
        // 将body数据存储起来
        String bodyStr = getBodyString(request);
        body = bodyStr.getBytes(Charset.defaultCharset());
    }

    public void setBody(byte[] body) {
        this.body = body;
    }

    /**
     * 获取请求Body
     *
     * @param request request
     * @return String
     */
    private String getBodyString(final ServletRequest request) {
        try {
            return inputStream2String(request.getInputStream());
        } catch (IOException e) {
            log.error("", e);
            throw new RuntimeException(e);
        }
    }

    /**
     * 获取请求Body
     *
     * @return String
     */
    public String getBodyString() {
        return new String(this.body, StandardCharsets.UTF_8);
    }

    /**
     * 将inputStream里的数据读取出来并转换成字符串
     *
     * @param inputStream inputStream
     * @return String
     */
    private String inputStream2String(InputStream inputStream) {
        StringBuilder sb = new StringBuilder();
        BufferedReader reader = null;

        try {
            reader = new BufferedReader(new InputStreamReader(inputStream, Charset.defaultCharset()));
            String line;
            while ((line = reader.readLine()) != null) {
                sb.append(line);
            }
        } catch (IOException e) {
            log.error("", e);
            throw new RuntimeException(e);
        } finally {
            if (reader != null) {
                try {
                    reader.close();
                } catch (IOException e) {
                    log.error("", e);
                }
            }
        }

        return sb.toString();
    }

    @Override
    public BufferedReader getReader() throws IOException {
        return new BufferedReader(new InputStreamReader(getInputStream()));
    }

    @Override
    public ServletInputStream getInputStream() throws IOException {

        final ByteArrayInputStream inputStream = new ByteArrayInputStream(body);

        return new ServletInputStream() {
            @Override
            public int read() throws IOException {
                return inputStream.read();
            }

            @Override
            public boolean isFinished() {
                return false;
            }

            @Override
            public boolean isReady() {
                return false;
            }

            @Override
            public void setReadListener(ReadListener readListener) {
            }
        };
    }
}