package com.zy.asrs.wms.common.security;

import com.alibaba.fastjson.JSON;
import com.zy.asrs.wms.utils.EncryptUtils;
import com.zy.asrs.wms.utils.WebkitParseUtils;
import javax.servlet.ReadListener;
import javax.servlet.ServletInputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;
import java.io.*;
import java.util.HashMap;
import java.util.Map;

public class CachedBodyHttpServletRequest extends HttpServletRequestWrapper {
    private final byte[] cachedBody;
    private final Map<String, String[]> parameterMap;

    public CachedBodyHttpServletRequest(HttpServletRequest request) throws IOException {
        super(request);
        String requestMethod = request.getMethod();
        if ("GET".equalsIgnoreCase(requestMethod)) {
            Map<String, String[]> map = request.getParameterMap();
            String jsonString = JSON.toJSONString(map);
            this.cachedBody = jsonString.getBytes();
            this.parameterMap = map;
        }else {
            // 读取请求体并缓存
            InputStream inputStream = request.getInputStream();
            // 方法来读取所有字节
            this.cachedBody = readBytesFromInputStream(inputStream);

            this.parameterMap = new HashMap<>();
            // 读取并解析表单数据
            parseRequestParameters();
        }
    }

    private byte[] readBytesFromInputStream(InputStream inputStream) throws IOException {
        ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
        byte[] buffer = new byte[1024];
        int bytesRead;
        while ((bytesRead = inputStream.read(buffer)) != -1) {
            byteArrayOutputStream.write(buffer, 0, bytesRead);
        }
        return byteArrayOutputStream.toByteArray();
    }

    @Override
    public ServletInputStream getInputStream() {
        return new CachedBodyServletInputStream(cachedBody);
    }

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

    @Override
    public String getParameter(String name) {
        String[] values = parameterMap.get(name);
        return (values != null && values.length > 0) ? values[0] : null;
    }

    @Override
    public Map<String, String[]> getParameterMap() {
        return parameterMap;
    }

    @Override
    public String[] getParameterValues(String name) {
        return parameterMap.get(name);
    }

    private static class CachedBodyServletInputStream extends ServletInputStream {
        private final ByteArrayInputStream inputStream;

        public CachedBodyServletInputStream(byte[] cachedBody) {
            this.inputStream = new ByteArrayInputStream(cachedBody);
        }

        @Override
        public boolean isFinished() {
            return inputStream.available() == 0;
        }

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

        @Override
        public void setReadListener(ReadListener listener) {
            throw new UnsupportedOperationException();
        }

        @Override
        public int read() {
            return inputStream.read();
        }
    }

    private void parseRequestParameters() {
        String string = new String(cachedBody);
        HashMap<String, Object> formData = WebkitParseUtils.getFormData(string);
        for (Map.Entry<String, Object> entry : formData.entrySet()) {
            parameterMap.put(entry.getKey(), new String[]{entry.getValue().toString()});
        }
    }
}