package com.qianwen.core.boot.request;

import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentMap;
import java.util.logging.Logger;
import java.util.regex.Matcher;
import java.util.regex.Pattern;


public final class XssHtmlFilter {
	private static final int REGEX_FLAGS_SI = 34;
	  
	  private static final Pattern P_COMMENTS = Pattern.compile("<!--(.*?)-->", 32);
	  
	  private static final Pattern P_COMMENT = Pattern.compile("^!--(.*)--$", 34);
	  
	  private static final Pattern P_TAGS = Pattern.compile("<(.*?)>", 32);
	  
	  private static final Pattern P_END_TAG = Pattern.compile("^/([a-z0-9]+)", 34);
	  
	  private static final Pattern P_START_TAG = Pattern.compile("^([a-z0-9]+)(.*?)(/?)$", 34);
	  
	  private static final Pattern P_QUOTED_ATTRIBUTES = Pattern.compile("([a-z0-9]+)=([\"'])(.*?)\\2", 34);
	  
	  private static final Pattern P_UNQUOTED_ATTRIBUTES = Pattern.compile("([a-z0-9]+)(=)([^\"\\s']+)", 34);
	  
	  private static final Pattern P_PROTOCOL = Pattern.compile("^([^:]+):", 34);
	  
	  private static final Pattern P_ENTITY = Pattern.compile("&#(\\d+);?");
	  
	  private static final Pattern P_ENTITY_UNICODE = Pattern.compile("&#x([0-9a-f]+);?");
	  
	  private static final Pattern P_ENCODE = Pattern.compile("%([0-9a-f]{2});?");
	  
	  private static final Pattern P_VALID_ENTITIES = Pattern.compile("&([^&;]*)(?=(;|&|$))");
	  
	  private static final Pattern P_VALID_QUOTES = Pattern.compile("(>|^)([^<]+?)(<|$)", 32);
	  
	  private static final Pattern P_END_ARROW = Pattern.compile("^>");
	  
	  private static final Pattern P_BODY_TO_END = Pattern.compile("<([^>]*?)(?=<|$)");
	  
	  private static final Pattern P_XML_CONTENT = Pattern.compile("(^|>)([^<]*?)(?=>)");
	  
	  private static final Pattern P_STRAY_LEFT_ARROW = Pattern.compile("<([^>]*?)(?=<|$)");
	  
	  private static final Pattern P_STRAY_RIGHT_ARROW = Pattern.compile("(^|>)([^<]*?)(?=>)");
	  
	  private static final Pattern P_AMP = Pattern.compile("&");
	  
	  private static final Pattern P_QUOTE = Pattern.compile("<");
	  
	  private static final Pattern P_LEFT_ARROW = Pattern.compile("<");
	  
	  private static final Pattern P_RIGHT_ARROW = Pattern.compile(">");
	  
	  private static final Pattern P_BOTH_ARROWS = Pattern.compile("<>");
	  
	  private static final ConcurrentMap<String, Pattern> P_REMOVE_PAIR_BLANKS = new ConcurrentHashMap<>();
	  
	  private static final ConcurrentMap<String, Pattern> P_REMOVE_SELF_BLANKS = new ConcurrentHashMap<>();
	  
	  private final Map<String, List<String>> vAllowed;
	  
	  private final Map<String, Integer> vTagCounts = new HashMap<>();
	  
	  private final String[] vSelfClosingTags;
	  
	  private final String[] vNeedClosingTags;
	  
	  private final String[] vDisallowed;
	  
	  private final String[] vProtocolAtts;
	  
	  private final String[] vAllowedProtocols;
	  
	  private final String[] vRemoveBlanks;
	  
	  private final String[] vAllowedEntities;
	  
	  private final boolean stripComment;
	  
	  private final boolean encodeQuotes;
	  
	  private boolean vDebug = false;
    private final boolean alwaysMakeTags;


   

    public XssHtmlFilter() {
    	this.vAllowed = new HashMap<>();
        ArrayList<String> aAtts = new ArrayList<>();
        aAtts.add("href");
        aAtts.add("target");
        this.vAllowed.put("a", aAtts);
        ArrayList<String> imgAtts = new ArrayList<>();
        imgAtts.add("src");
        imgAtts.add("width");
        imgAtts.add("height");
        imgAtts.add("alt");
        this.vAllowed.put("img", imgAtts);
        ArrayList<String> noAtts = new ArrayList<>();
        this.vAllowed.put("b", noAtts);
        this.vAllowed.put("strong", noAtts);
        this.vAllowed.put("i", noAtts);
        this.vAllowed.put("em", noAtts);
        this.vSelfClosingTags = new String[] { "img" };
        this.vNeedClosingTags = new String[] { "a", "b", "strong", "i", "em" };
        this.vDisallowed = new String[0];
        this.vAllowedProtocols = new String[] { "http", "mailto", "https" };
        this.vProtocolAtts = new String[] { "src", "href" };
        this.vRemoveBlanks = new String[] { "a", "b", "strong", "i", "em" };
        this.vAllowedEntities = new String[] { "amp", "gt", "lt", "quot" };
        this.stripComment = true;
        this.encodeQuotes = true;
        this.alwaysMakeTags = false;
    }

    public XssHtmlFilter(final boolean debug) {
        this();
        this.vDebug = debug;
    }

    public XssHtmlFilter(final Map<String, Object> conf) {
    	assert conf.containsKey("vAllowed") : "configuration requires vAllowed";
        assert conf.containsKey("vSelfClosingTags") : "configuration requires vSelfClosingTags";
        assert conf.containsKey("vNeedClosingTags") : "configuration requires vNeedClosingTags";
        assert conf.containsKey("vDisallowed") : "configuration requires vDisallowed";
        assert conf.containsKey("vAllowedProtocols") : "configuration requires vAllowedProtocols";
        assert conf.containsKey("vProtocolAtts") : "configuration requires vProtocolAtts";
        assert conf.containsKey("vRemoveBlanks") : "configuration requires vRemoveBlanks";
        assert conf.containsKey("vAllowedEntities") : "configuration requires vAllowedEntities";
        this.vAllowed = Collections.unmodifiableMap((HashMap)conf.get("vAllowed"));
        this.vSelfClosingTags = (String[])conf.get("vSelfClosingTags");
        this.vNeedClosingTags = (String[])conf.get("vNeedClosingTags");
        this.vDisallowed = (String[])conf.get("vDisallowed");
        this.vAllowedProtocols = (String[])conf.get("vAllowedProtocols");
        this.vProtocolAtts = (String[])conf.get("vProtocolAtts");
        this.vRemoveBlanks = (String[])conf.get("vRemoveBlanks");
        this.vAllowedEntities = (String[])conf.get("vAllowedEntities");
        this.stripComment = conf.containsKey("stripComment") ? ((Boolean)conf.get("stripComment")).booleanValue() : true;
        this.encodeQuotes = conf.containsKey("encodeQuotes") ? ((Boolean)conf.get("encodeQuotes")).booleanValue() : true;
        this.alwaysMakeTags = conf.containsKey("alwaysMakeTags") ? ((Boolean)conf.get("alwaysMakeTags")).booleanValue() : true;
    }

    private void reset() {
        this.vTagCounts.clear();
    }

    private void debug(final String msg) {
        if (this.vDebug) {
            Logger.getAnonymousLogger().info(msg);
        }
    }

    public static String chr(final int decimal) {
        return String.valueOf((char) decimal);
    }

    public static String htmlSpecialChars(final String s) {
        String result = regexReplace(P_AMP, "&amp;", s);
        return regexReplace(P_RIGHT_ARROW, "&gt;", regexReplace(P_LEFT_ARROW, "&lt;", regexReplace(P_QUOTE, "&quot;", result)));
    }

    public String filter(final String input) {
        reset();
        debug("************************************************");
        debug("              INPUT: " + input);
        String s = escapeComments(input);
        debug("     escapeComments: " + s);
        String s2 = balanceHtml(s);
        debug("        balanceHtml: " + s2);
        String s3 = checkTags(s2);
        debug("          checkTags: " + s3);
        String s4 = processRemoveBlanks(s3);
        debug("processRemoveBlanks: " + s4);
        String s5 = validateEntities(s4);
        debug("    validateEntites: " + s5);
        debug("************************************************\n\n");
        return s5;
    }

    public boolean isAlwaysMakeTags() {
        return this.alwaysMakeTags;
    }

    public boolean isStripComments() {
        return this.stripComment;
    }

    private String escapeComments(final String s) {
        Matcher m = P_COMMENTS.matcher(s);
        StringBuffer buf = new StringBuffer();
        if (m.find()) {
            String match = m.group(1);
            m.appendReplacement(buf, Matcher.quoteReplacement("<!--" + htmlSpecialChars(match) + "-->"));
        }
        m.appendTail(buf);
        return buf.toString();
    }

    private String balanceHtml(String s) {
        String s2;
        if (this.alwaysMakeTags) {
            s2 = regexReplace(P_XML_CONTENT, "$1<$2", regexReplace(P_BODY_TO_END, "<$1>", regexReplace(P_END_ARROW, "", s)));
        } else {
            s2 = regexReplace(P_BOTH_ARROWS, "", regexReplace(P_STRAY_RIGHT_ARROW, "$1$2&gt;<", regexReplace(P_STRAY_LEFT_ARROW, "&lt;$1", s)));
        }
        return s2;
    }

    private String checkTags(String s) {
        Matcher m = P_TAGS.matcher(s);
        StringBuffer buf = new StringBuffer();
        while (m.find()) {
            String replaceStr = m.group(1);
            m.appendReplacement(buf, Matcher.quoteReplacement(processTag(replaceStr)));
        }
        m.appendTail(buf);
        String s2 = buf.toString();
        for (String key : this.vTagCounts.keySet()) {
            for (int ii = 0; ii < this.vTagCounts.get(key).intValue(); ii++) {
                s2 = s2 + "</" + key + ">";
            }
        }
        return s2;
    }

    private String processRemoveBlanks(final String s) {
        String[] strArr;
        String result = s;
        for (String tag : this.vRemoveBlanks) {
            if (!P_REMOVE_PAIR_BLANKS.containsKey(tag)) {
                P_REMOVE_PAIR_BLANKS.putIfAbsent(tag, Pattern.compile("<" + tag + "(\\s[^>]*)?></" + tag + ">"));
            }
            String result2 = regexReplace(P_REMOVE_PAIR_BLANKS.get(tag), "", result);
            if (!P_REMOVE_SELF_BLANKS.containsKey(tag)) {
                P_REMOVE_SELF_BLANKS.putIfAbsent(tag, Pattern.compile("<" + tag + "(\\s[^>]*)?/>"));
            }
            result = regexReplace(P_REMOVE_SELF_BLANKS.get(tag), "", result2);
        }
        return result;
    }

    private static String regexReplace(final Pattern regexPattern, final String replacement, final String s) {
        Matcher m = regexPattern.matcher(s);
        return m.replaceAll(replacement);
    }

    private String processTag(final String s) {
        Matcher m = P_END_TAG.matcher(s);
        if (m.find()) {
            String name = m.group(1).toLowerCase();
            if (allowed(name) && !inArray(name, this.vSelfClosingTags) && this.vTagCounts.containsKey(name)) {
                this.vTagCounts.put(name, Integer.valueOf(this.vTagCounts.get(name).intValue() - 1));
                return "</" + name + ">";
            }
        }
        Matcher m2 = P_START_TAG.matcher(s);
        if (m2.find()) {
            String name2 = m2.group(1).toLowerCase();
            String body = m2.group(2);
            String ending = m2.group(3);
            if (allowed(name2)) {
                String params = "";
                Matcher m22 = P_QUOTED_ATTRIBUTES.matcher(body);
                Matcher m3 = P_UNQUOTED_ATTRIBUTES.matcher(body);
                List<String> paramNames = new ArrayList<>();
                List<String> paramValues = new ArrayList<>();
                while (m22.find()) {
                    paramNames.add(m22.group(1));
                    paramValues.add(m22.group(3));
                }
                while (m3.find()) {
                    paramNames.add(m3.group(1));
                    paramValues.add(m3.group(3));
                }
                for (int ii = 0; ii < paramNames.size(); ii++) {
                    String paramName = paramNames.get(ii).toLowerCase();
                    String paramValue = paramValues.get(ii);
                    if (allowedAttribute(name2, paramName)) {
                        if (inArray(paramName, this.vProtocolAtts)) {
                            paramValue = processParamProtocol(paramValue);
                        }
                        params = params + " " + paramName + "=\"" + paramValue + "\"";
                    }
                }
                if (inArray(name2, this.vSelfClosingTags)) {
                    ending = " /";
                }
                if (inArray(name2, this.vNeedClosingTags)) {
                    ending = "";
                }
                if (ending == null || ending.length() < 1) {
                    if (this.vTagCounts.containsKey(name2)) {
                        this.vTagCounts.put(name2, Integer.valueOf(this.vTagCounts.get(name2).intValue() + 1));
                    } else {
                        this.vTagCounts.put(name2, 1);
                    }
                } else {
                    ending = " /";
                }
                return "<" + name2 + params + ending + ">";
            }
            return "";
        }
        Matcher m4 = P_COMMENT.matcher(s);
        if (!this.stripComment && m4.find()) {
            return "<" + m4.group() + ">";
        }
        return "";
    }

    private String processParamProtocol(String s) {
        String s2 = decodeEntities(s);
        Matcher m = P_PROTOCOL.matcher(s2);
        if (m.find()) {
            String protocol = m.group(1);
            if (!inArray(protocol, this.vAllowedProtocols)) {
                s2 = "#" + s2.substring(protocol.length() + 1);
                if (s2.startsWith("#//")) {
                    s2 = "#" + s2.substring(3);
                }
            }
        }
        return s2;
    }

    private String decodeEntities(String s) {
        StringBuffer buf = new StringBuffer();
        Matcher m = P_ENTITY.matcher(s);
        while (m.find()) {
            String match = m.group(1);
            int decimal = Integer.decode(match).intValue();
            m.appendReplacement(buf, Matcher.quoteReplacement(chr(decimal)));
        }
        m.appendTail(buf);
        String s2 = buf.toString();
        StringBuffer buf2 = new StringBuffer();
        Matcher m2 = P_ENTITY_UNICODE.matcher(s2);
        while (m2.find()) {
            String match2 = m2.group(1);
            int decimal2 = Integer.valueOf(match2, 16).intValue();
            m2.appendReplacement(buf2, Matcher.quoteReplacement(chr(decimal2)));
        }
        m2.appendTail(buf2);
        String s3 = buf2.toString();
        StringBuffer buf3 = new StringBuffer();
        Matcher m3 = P_ENCODE.matcher(s3);
        while (m3.find()) {
            String match3 = m3.group(1);
            int decimal3 = Integer.valueOf(match3, 16).intValue();
            m3.appendReplacement(buf3, Matcher.quoteReplacement(chr(decimal3)));
        }
        m3.appendTail(buf3);
        String s4 = buf3.toString();
        return validateEntities(s4);
    }

    private String validateEntities(final String s) {
        StringBuffer buf = new StringBuffer();
        Matcher m = P_VALID_ENTITIES.matcher(s);
        while (m.find()) {
            String one = m.group(1);
            String two = m.group(2);
            m.appendReplacement(buf, Matcher.quoteReplacement(checkEntity(one, two)));
        }
        m.appendTail(buf);
        return encodeQuotes(buf.toString());
    }

    private String encodeQuotes(final String s) {
        if (this.encodeQuotes) {
            StringBuffer buf = new StringBuffer();
            Matcher m = P_VALID_QUOTES.matcher(s);
            while (m.find()) {
                String one = m.group(1);
                String two = m.group(2);
                String three = m.group(3);
                m.appendReplacement(buf, Matcher.quoteReplacement(one + regexReplace(P_QUOTE, "&quot;", two) + three));
            }
            m.appendTail(buf);
            return buf.toString();
        }
        return s;
    }

    private String checkEntity(final String preamble, final String term) {
        return (";".equals(term) && isValidEntity(preamble)) ? '&' + preamble : "&amp;" + preamble;
    }

    private boolean isValidEntity(final String entity) {
        return inArray(entity, this.vAllowedEntities);
    }

    private static boolean inArray(final String s, final String[] array) {
        for (String item : array) {
            if (item != null && item.equals(s)) {
                return true;
            }
        }
        return false;
    }

    private boolean allowed(final String name) {
        return (this.vAllowed.isEmpty() || this.vAllowed.containsKey(name)) && !inArray(name, this.vDisallowed);
    }

    private boolean allowedAttribute(final String name, final String paramName) {
        return allowed(name) && (this.vAllowed.isEmpty() || this.vAllowed.get(name).contains(paramName));
    }
}