package cn.com.goldenwater.dcproj.filter;

import net.sf.json.JSONArray;
import net.sf.json.JSONObject;
import org.apache.commons.lang3.StringUtils;
import org.slf4j.LoggerFactory;

import javax.servlet.ReadListener;
import javax.servlet.ServletInputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.*;
import java.nio.charset.StandardCharsets;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

/**
 * @author 81229
 * 防xss攻击方案
 */
public class XssHttpServletRequestWrapper extends BodyReaderHttpServletRequestWrapper {

    private final String badStr = "'|and|exec|execute|insert|select|delete|update|count|drop|" +
            "char|declare|sitename|net user|xp_cmdshell|;|or|+|like'|and|create|" +
            "table|from|grant|use|group_concat|column_name" +
            "information_schema.columns|table_schema|union|where|" +
            "chr|mid|master|truncate|--|,|like|//|/|%|frame|style|script|DBMS_PIPE|**/";
    private org.slf4j.Logger logger = LoggerFactory.getLogger(getClass());
    /**
     * Constructs a request object wrapping the given request.
     *
     * @param request The request to wrap
     * @throws IllegalArgumentException if the request is null
     */
    HttpServletRequest request;
    HttpServletResponse response;

    public XssHttpServletRequestWrapper(HttpServletRequest request, HttpServletResponse response) {
        super(request);
        this.request = request;
        this.response = response;
    }


    @Override
    public String getHeader(String name) {
        String value = super.getHeader(name);
        if (StringUtils.isEmpty(value)) {
            return value;
        } else {
            return cleanXSS(value);
        }

    }

    @Override
    public String getParameter(String name) {
        String value = super.getParameter(name);
        if (StringUtils.isEmpty(value)) {
            return value;
        } else {
            return cleanXSS(value);
        }

    }

    @Override
    public Object getAttribute(String name) {
        Object object = super.getAttribute(name);
        if (object instanceof Map) {
            return getParams((Map<String, Object>) object);
        }
        if (object instanceof String) {
            return cleanXSS(object + "");
        }
        return object;
    }

    @Override
    public String[] getParameterValues(String name) {
        String[] values = super.getParameterValues(name);
        if (values != null) {
            int length = values.length;
            String[] escapseValues = new String[length];
            for (int i = 0; i < length; i++) {
                escapseValues[i] = cleanXSS(values[i]);
            }
            return escapseValues;
        }
        return super.getParameterValues(name);
    }

    private Map<String, Object> getParams(Map<String, Object> map) {
        Map<String, Object> resultMap = new HashMap<>();
        for (String key : map.keySet()) {
            Object val = map.get(key);
            if (map.get(key) instanceof String) {
                resultMap.put(key, cleanXSS(val.toString()));
            } else {
                resultMap.put(key, val);
            }
        }
        return resultMap;
    }

    @Override
    public ServletInputStream getInputStream() throws IOException {
        String str = getRequestBody(super.getInputStream());
        if (StringUtils.isNotBlank(str)) {
            if (str.startsWith("{")) {
                JSONObject jsonObject = JSONObject.fromObject(str);
                Map<String, Object> map = (Map<String, Object>) JSONObject.toBean(jsonObject, Map.class);
                str = JSONObject.fromObject(getParams(map)).toString();
            } else if (str.startsWith("[")) {
                JSONArray jsonArray = JSONArray.fromObject(str);
                List<Map<String, Object>> paramsList = new ArrayList<>();
                if (jsonArray != null && jsonArray.size() > 0) {
                    if (jsonArray.get(0) instanceof JSONArray) {
                        for (int i = 0; i < jsonArray.size(); i++) {
                            JSONObject jsonObject = jsonArray.getJSONObject(i);
                            Map<String, Object> map = (Map<String, Object>) JSONObject.toBean(jsonObject, Map.class);
                            paramsList.add(getParams(map));
                        }
                        str = JSONArray.fromObject(paramsList).toString();
                    }
                }
            }

        }
        final ByteArrayInputStream bais = new ByteArrayInputStream(str.getBytes());

        return new ServletInputStream() {

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

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

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

            @Override
            public void setReadListener(ReadListener listener) {

            }
        };
    }


    private String cleanXSS(String value) {
//        value = RequestUtils.cleanScript(value);
//        if (value.contains("error-333:")){
//            try {
//                ReturnUtils.responseFail(response, "路径存在异常，请仔细检查", 5555);
//            } catch (Exception e) {
//                e.printStackTrace();
//            }
//            return "";
//        }

       /* value = value.replaceAll("'", "& #39;");
        value = value.replaceAll("eval\\((.*)\\)", "");
        value = value.replaceAll("[\\\"\\\'][\\s]*javascript:(.*)[\\\"\\\']", "\"\"");
        value = value.replaceAll("script", "");
//        value = value.replaceAll("[*]","["+"*]");
        value = value.replaceAll("[?]","["+"?]");
        String[] values = value.split(" ");
        String[] badStrs = badStr.split("\\|");
        for (int i = 0;i<badStrs.length;i++){
            for (int j = 0;j<values.length;j++){
                if (values[j].equalsIgnoreCase(badStrs[i])){
                    values[j] = "forbid";
                }
            }
        }
        StringBuilder sb = new StringBuilder();
        for (int i = 0;i<values.length;i++){
            if (i == values.length-1){
                sb.append(values[i]);
            } else {
                sb.append(values[i]+" ");
            }
        }
        value = sb.toString();*/
//        System.out.println("outer-->"+value);
        return value;
    }


    public static String getRequestBody(InputStream stream) {
        String line = "";
        StringBuilder body = new StringBuilder();
        // 读取POST提交的数据内容
        BufferedReader reader = new BufferedReader(new InputStreamReader(stream, StandardCharsets.UTF_8));
        try {
            while ((line = reader.readLine()) != null) {
                body.append(line);
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
        return body.toString();
    }

}