package com.kidgrow.zuul.filter.support;

import lombok.extern.slf4j.Slf4j;
import org.apache.commons.io.IOUtils;
import javax.servlet.ReadListener;
import javax.servlet.ServletInputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;
import java.io.*;
import java.util.*;

/**
 * 石家庄喜高科技有限责任公司 版权所有 © Copyright 2020<br>
 *
 * @Description: <br>
 * @Project: <br>
 * @CreateDate: Created in 2020/2/4 14:49 <br>
 * @Author: <a href="4345453@kidgrow.com">liuke</a>
 */
@Slf4j
public class ModifyHttpServletRequestWrapper extends HttpServletRequestWrapper {
    private final byte[] body;
    private Map<String, String> customHeaders;

    public ModifyHttpServletRequestWrapper(HttpServletRequest request) throws IOException {
        super(request);
        ByteArrayOutputStream baos = new ByteArrayOutputStream();
        IOUtils.copy(request.getInputStream(), baos);
        this.body = baos.toByteArray();
        this.customHeaders = new HashMap<>();
    }

    @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 boolean isFinished() {
                return false;
            }

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

            @Override
            public void setReadListener(ReadListener readListener) {

            }
        };
    }

    public void putHeader(String name, String value) {
        this.customHeaders.put(name, value);
    }

    @Override
    public String getHeader(String name) {
        String value = this.customHeaders.get(name);
        if (value != null) {
            return value;
        }
        return ((HttpServletRequest) getRequest()).getHeader(name);
    }

    @Override
    public Enumeration<String> getHeaderNames() {
        Set<String> set = new HashSet<>(customHeaders.keySet());
        Enumeration<String> enumeration = ((HttpServletRequest) getRequest()).getHeaderNames();
        while (enumeration.hasMoreElements()) {
            String name = enumeration.nextElement();
            set.add(name);
        }
        return Collections.enumeration(set);
    }
}