package com.ruoyi.auth.fliter;

import lombok.extern.log4j.Log4j2;
import org.apache.commons.lang3.exception.ExceptionUtils;

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

/**
 * 构建可重复读取inputStream的request
 *
 * @author linzhang
 */
@Log4j2
public class RepeatedlyRequestWrapper extends HttpServletRequestWrapper
{
    private final byte[] body;

    public RepeatedlyRequestWrapper(HttpServletRequest request, ServletResponse response) throws IOException
    {
        super(request);
        request.setCharacterEncoding("UTF-8");
        response.setCharacterEncoding("UTF-8");

        body = getBodyString(request).getBytes("UTF-8");
    }

    public static String getBodyString(ServletRequest request)
    {
        StringBuilder sb = new StringBuilder();
        BufferedReader reader = null;
        try (InputStream inputStream = request.getInputStream())
        {
            reader = new BufferedReader(new InputStreamReader(inputStream, Charset.forName("UTF-8")));
            String line = "";
            while ((line = reader.readLine()) != null)
            {
                sb.append(line);
            }
        }
        catch (IOException e)
        {
            log.warn("getBodyString出现问题！");
        }
        finally
        {
            if (reader != null)
            {
                try
                {
                    reader.close();
                }
                catch (IOException e)
                {
                    log.error(ExceptionUtils.getMessage(e));
                }
            }
        }
        return sb.toString();
    }

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

    @Override
    public ServletInputStream getInputStream() throws IOException
    {
        final ByteArrayInputStream bais = new ByteArrayInputStream(body);
        return new ServletInputStream()
        {
            @Override
            public int read() throws IOException
            {
                return bais.read();
            }

            @Override
            public int available() throws IOException
            {
                return body.length;
            }

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

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

            @Override
            public void setReadListener(ReadListener readListener)
            {

            }
        };
    }
}