/*
* The contents of this file are subject to the Mozilla Public License Version 1.1
* (the "License"); you may not use this file except in compliance with the License.
* You may obtain a copy of the License at .
*
* Software distributed under the License is distributed on an "AS IS" basis, WITHOUT
* WARRANTY OF ANY KIND, either express or implied. See the License for the specific
* language governing rights and limitations under the License.
*
* The Original Code is the Venice Web Community System.
*
* The Initial Developer of the Original Code is Eric J. Bowersox ,
* for Silverwrist Design Studios. Portions created by Eric J. Bowersox are
* Copyright (C) 2001 Eric J. Bowersox/Silverwrist Design Studios. All Rights Reserved.
*
* Contributor(s):
*/
package com.silverwrist.venice.htmlcheck.impl;
import java.util.*;
import com.silverwrist.venice.htmlcheck.*;
class HTMLCheckerImpl implements HTMLChecker, HTMLCheckerBackend, RewriterServices
{
/*--------------------------------------------------------------------------------
* Wrapper for Rewriters to implement counting where necessary
*--------------------------------------------------------------------------------
*/
static class CountingRewriter implements Rewriter
{
private Rewriter inner;
private int count = 0;
public CountingRewriter(Rewriter inner)
{
this.inner = inner;
} // end constructor
public String getName()
{
return inner.getName();
} // end getName
public MarkupData rewrite(String data, RewriterServices svc)
{
MarkupData rc = inner.rewrite(data,svc);
if (rc!=null)
count++;
return rc;
} // end rewrite
public int getCount()
{
return count;
} // end getCount
public void reset()
{
count = 0;
} // end reset
} // end class CountingRewriter
/*--------------------------------------------------------------------------------
* State machine constants
*--------------------------------------------------------------------------------
*/
private static final short ST_WHITESPACE = 0;
private static final short ST_CHARS = 1;
private static final short ST_LEFTANGLE = 2;
private static final short ST_TAG = 3;
private static final short ST_PAREN = 4;
private static final short ST_TAGQUOTE = 5;
/*--------------------------------------------------------------------------------
* Attributes
*--------------------------------------------------------------------------------
*/
private HTMLCheckerConfigImpl config; // the configuration we're working from
private boolean started = false; // have we started parsing?
private boolean finished = false; // have we finished parsing?
private short state = ST_WHITESPACE; // current parser state
private char quote_char; // quote character to match
private int paren_level = 0; // parenthesization level
private short columns = 0; // current number of columns
private int lines = 0; // current number of lines
private int nobreak_count = 0; // "no-break" count
private boolean trigger_WBR = false; // word break trigger
private StringBuffer output_buffer = null; // output buffer for characters
private StringBuffer temp_buffer = null; // temporary buffer used within one state
private Vector tag_stack = null; // stack of tags that have been opened
private Hashtable counters = new Hashtable(); // the CountingRewriter instances
private Vector string_rewriters = new Vector(); // string rewriter instances
private Vector word_rewriters = new Vector(); // word rewriter instances
private Vector tag_rewriters = new Vector(); // tag rewriter instances
private Vector paren_rewriters = new Vector(); // paren rewriter instances
private Hashtable context_data = new Hashtable(); // context variables
/*--------------------------------------------------------------------------------
* Constructor
*--------------------------------------------------------------------------------
*/
HTMLCheckerImpl(HTMLCheckerConfigImpl config)
{
TagRepository.init();
this.config = config;
copyRewriters(string_rewriters,config.getStringRewriters());
copyRewriters(word_rewriters,config.getWordRewriters());
copyRewriters(tag_rewriters,config.getTagRewriters());
copyRewriters(paren_rewriters,config.getParenRewriters());
} // end constructor
/*--------------------------------------------------------------------------------
* Internal functions
*--------------------------------------------------------------------------------
*/
private static final boolean isWordChar(char ch)
{
return (Character.isUpperCase(ch) || Character.isLowerCase(ch) || (ch=='-'));
} // end isWordChar
private static final int getRunLength(StringBuffer buf)
{
boolean word_char = isWordChar(buf.charAt(0));
int l = 1;
while (l0)
{ // look through all the output filters to see what we can do
Iterator it = filters.iterator();
while (!handled && it.hasNext())
{ // look for an output filter that matches this character
OutputFilter of = (OutputFilter)(it.next());
handled = of.tryOutputCharacter(output_buffer,ch);
} // end while
} // end if
if (!handled) // output the character
output_buffer.append(ch);
if (count_cols && (config.getWordWrapLength()>0))
columns++; // adjust column indicator
} // end emitChar
private void emitString(String str, List filters, boolean count_cols)
{
boolean real_count_cols = count_cols && (config.getWordWrapLength()>0);
if (filters.size()==0)
{ // if there are no filters, just append the entire string directly
output_buffer.append(str);
if (real_count_cols)
columns += (short)(str.length());
return;
} // end if
String temp = str;
while ((temp!=null) && (temp.length()>0))
{ // We output as much of the string as we possibly can at once. For starters,
// assume we're going to output the whole thing.
int output_len = temp.length();
// Now look at each of the output filters to see if we should try outputting
// a lesser amount (i.e., does the string contain a "stopper" that one of the
// output filters would like to mogrify?)
Iterator it = filters.iterator();
OutputFilter stopper = null;
while (it.hasNext() && (output_len>0))
{ // look to find the length of characters that doesn't match this filter
OutputFilter of = (OutputFilter)(it.next());
int lnm = of.lengthNoMatch(temp);
if ((lnm>=0) && (lnm0)
{ // At least this many unaltered characters can be output, so copy them.
output_buffer.append(temp.substring(0,output_len));
if (real_count_cols)
columns += (short)output_len;
} // end if
if (stopper!=null)
{ // one of the output filters stopped us, so invoke it
char tmpch = temp.charAt(output_len++);
if (!(stopper.tryOutputCharacter(output_buffer,tmpch)))
output_buffer.append(tmpch);
if (real_count_cols)
columns++;
} // end if
// Chop the string down the middle and go around again.
if (output_len==temp.length())
temp = null;
else if (output_len>0)
temp = temp.substring(output_len);
} // end while (still data left to append)
} // end emitString
private void emitLineBreak()
{
emitString("\r\n",config.getRawOutputFilters(),false);
if (config.getWordWrapLength()>0)
columns = 0;
lines++;
} // end emitLineBreak
private void emitPossibleLineBreak()
{
if ((config.getWordWrapLength()>0) && (nobreak_count<=0) && (columns>=config.getWordWrapLength()))
emitLineBreak();
} // end emitPossibleLineBreak
private void ensureSpaceOnLine(int nchars)
{
if ((config.getWordWrapLength()>0) && (nobreak_count<=0))
{ // line break might be required here
int remain_space = (int)(config.getWordWrapLength() - columns);
if (remain_space0)
{ // calculate where the next line break is
int line_break = temp_buffer.toString().indexOf('\n');
int output_len = line_break;
if (output_len<0)
output_len = temp_buffer.length();
if ((config.getWordWrapLength()>0) && (nobreak_count<=0))
{ // adjust output if necessary for word wrapping
int remain_space = (int)(config.getWordWrapLength() - columns);
if (remain_space0)
emitString(temp_buffer.substring(0,output_len),config.getOutputFilters(),true);
if (line_break>=0)
{ // there's a line break present - emit the line break
emitLineBreak(); // output the line break character
if (++line_break0) && (nobreak_count<=0))
{ // we can output the line break anywhere in the subsequence...
while (nchars>0)
{ // figure out how many characters we can output WITHOUT causing a line break
int curlen = nchars;
int remaining_space = (int)(config.getWordWrapLength() - columns);
if (curlen>remaining_space)
curlen = remaining_space;
// output those characters
emitString(temp_buffer.substring(0,curlen),config.getOutputFilters(),true);
temp_buffer.delete(0,curlen);
nchars -= curlen;
if (columns==config.getWordWrapLength())
emitLineBreak(); // and line break us to get to the next line
} // end while
} // end if
else
{ // just output the run of characters straight
emitString(temp_buffer.substring(0,nchars),config.getOutputFilters(),true);
temp_buffer.delete(0,nchars);
} // end else
} // end emitFromStartOfTempBuffer
private void doFlushString()
{
MarkupData md = attemptRewrite(string_rewriters,temp_buffer.toString());
if (md!=null)
{ // we've got something marked up! output it...
emitMarkupData(md);
temp_buffer.setLength(0);
return;
} // end if
while (temp_buffer.length()>0)
{ // find the length of the initial string of word or non-word characters
int sublen = getRunLength(temp_buffer);
if (isWordChar(temp_buffer.charAt(0)))
{ // we need to check the word...but first, we must eliminate leading hyphens
int hyph_count = 0;
while ((hyph_count0) && (temp_buffer.charAt(word_len-1)=='-'))
{ // decrement word length, increment hyphen count
hyph_count++;
word_len--;
} // end while
if (word_len>0)
{ // extract the word from the start of the buffer
String word = temp_buffer.substring(0,word_len);
temp_buffer.delete(0,word_len);
// try to rewrite this word...
md = attemptRewrite(word_rewriters,word);
if (md!=null)
emitMarkupData(md);
else
{ // just output the word normally
ensureSpaceOnLine(word.length());
emitString(word,config.getOutputFilters(),true);
} // end else
} // end if
// now emit the rest of the hyphens
emitFromStartOfTempBuffer(hyph_count);
} // end if
else // just emit this many characters, line-breaking where required
emitFromStartOfTempBuffer(sublen);
} // end while
} // end doFlushString
private boolean handleAsHTML()
{
trigger_WBR = false; // initialize
// Figure out the place in the buffer where the command word starts.
int start_cmd = 0;
boolean closing_tag = false;
if ((start_cmdTagRepository.getMaxTagLength()))
return false; // the command word is empty or is just too long to be an HTML tag
// Look up the tag name to get a tag index from the repository.
int tag_index = TagRepository.tagNameToIndex(temp_buffer.substring(start_cmd,end_cmd));
if (tag_index<0)
return false; // not a known HTML tag
// Look up the tag object that corresponds to the tag index.
SimpleTag tagobj = TagRepository.tagIndexToObject(tag_index);
if (closing_tag && !(tagobj.allowClose()))
return false; // this is a closing tag, and this tag doesn't permit the "close" form
// Get the HTML tag set index for this tag, and see if we allow that set.
int tag_set_id = TagRepository.tagIndexToSet(tag_index);
if (!(config.isTagSetAllowed(tag_set_id)) && !(config.getDiscardHTMLTags()))
return false; // we're not allowing it, we're not discarding it, so punt!
boolean valid = false;
if (!(config.getDiscardHTMLTags()) && tagobj.balanceTags())
{ // this tag needs to be balanced - here is where we manipulate the stack
if (closing_tag)
{ // hunt through the list to find the most recently-opened tag of this type
int i = tag_stack.size() - 1;
while (i>=0)
{ // look through the stack...
Integer foo = (Integer)(tag_stack.get(i));
if (foo.intValue()==tag_index)
{ // found it - remove it from the tag stack
tag_stack.remove(i);
valid = true;
break;
} // end if
} // end while
} // end if
else
{ // push a new opening tag!
tag_stack.add(new Integer(tag_index));
valid = true;
} // end else
} // end if
// else tag doesn't need to be auto-balanced, or is being discarded
if (!valid && !(config.getDiscardHTMLTags()))
return false; // not validated by the stack code, and not being discarded
// Give the tag object one last chance to dictate what we do with the tag.
String real_tag_data = tagobj.rewriteTagContents(temp_buffer.toString(),closing_tag,this);
if ((real_tag_data==null) || config.getDiscardHTMLTags())
return true; // tag is being erased by rewriter, or is being discarded anyway
// Emit the tag to the output.
emitChar('<',config.getRawOutputFilters(),false);
emitString(real_tag_data,config.getRawOutputFilters(),false);
emitChar('>',config.getRawOutputFilters(),false);
// Determine whether this tag causes a "logical line break."
boolean logical_line_break = false;
if (trigger_WBR && !closing_tag && (nobreak_count>0))
logical_line_break = true;
else
logical_line_break = tagobj.causeLineBreak(closing_tag);
if (logical_line_break)
columns = 0;
return true; // handled!
} // end handleAsHTML()
private void finishTag()
{
if (handleAsHTML())
{ // the tag has been handled as an HTML tag - bail out immediately
temp_buffer.setLength(0);
state = ST_WHITESPACE;
return;
} // end if
// now try to handle it using a tag rewriter
MarkupData md = attemptRewrite(tag_rewriters,temp_buffer.toString());
if (md!=null)
{ // we've got something marked up! output it...
emitMarkupData(md,'<','>');
temp_buffer.setLength(0);
state = ST_WHITESPACE;
return;
} // end if
// This tag has been rejected! We need to process it normally, as character data.
String rejection = temp_buffer.toString();
temp_buffer.setLength(0);
temp_buffer.append('<');
state = ST_CHARS;
if (rejection.length()>0)
parse(rejection); // just run it through the parser, now that we've fixed up the state
parse(">");
} // end finishTag
private void finishParen()
{
// Try to handle the paren element using a paren rewriter.
MarkupData md = attemptRewrite(paren_rewriters,temp_buffer.toString());
if (md!=null)
{ // we've got something marked up! output it...
emitMarkupData(md,'(',')');
temp_buffer.setLength(0);
state = ST_WHITESPACE;
paren_level = 0;
return;
} // end if
// This tag has been rejected! We need to process it normally, as character data.
String rejection = temp_buffer.toString();
temp_buffer.setLength(0);
temp_buffer.append('(');
state = ST_CHARS;
paren_level = 0;
if (rejection.length()>0)
parse(rejection); // just run it through the parser, now that we've fixed up the state
parse(")");
} // end finishParen
private void parse(String str)
{
int i = 0;
while (i': // end tag
finishTag(); // this changes the state, and maybe calls parse() recursively
i++;
break;
case '\'': // go into "quote string" mode inside tag
case '\"':
temp_buffer.append(ch);
state = ST_TAGQUOTE;
quote_char = ch;
i++;
break;
default: // just append more data to the temp buffer
temp_buffer.append(ch);
i++;
break;
} // end switch
} // end case
break;
case ST_PAREN:
{ // inside parentheses - try to build something up
switch (ch)
{
case '(': // append the open parenthesis and kick it up a notch!
temp_buffer.append(ch);
paren_level++;
i++;
break;
case ')':
if (paren_level==0)
finishParen(); // will change the parser state
else
{ // append the close parenthesis and kick it DOWN a notch
temp_buffer.append(ch);
paren_level--;
} // end else
i++;
break;
default:
temp_buffer.append(ch);
i++;
break;
} // end switch
} // end case
break;
case ST_TAGQUOTE:
temp_buffer.append(ch);
if (ch==quote_char) // close quote seen - go back to ST_TAG state
state = ST_TAG;
i++;
break;
default:
throw new IllegalStateException("invalid parser state value");
} // end switch
} // end while (looking through string)
} // end parse
/*--------------------------------------------------------------------------------
* Implementations from interface HTMLChecker
*--------------------------------------------------------------------------------
*/
public void append(String str) throws AlreadyFinishedException
{
if (finished)
throw new AlreadyFinishedException();
if (!started)
{ // initialize the parser state
initState();
started = true;
} // end if
parse(str); // parse things
} // end append
public void finish() throws AlreadyFinishedException
{
if (finished)
throw new AlreadyFinishedException();
if (!started)
{ // set up the initial parser state (so we don't kill ourselves later)
initState();
started = true;
} // end if
// This is the "end parse" loop, in which we resolve any funny state the parser has
// found itself in and clear out the internal buffers.
boolean running = false;
do
{ // what we do depends on the parser state...
switch (state)
{
case ST_WHITESPACE:
break; // discard any whitespace at the end of output
case ST_CHARS:
doFlushString(); // flush out the temporary buffer
break;
case ST_LEFTANGLE: // just emit a '<' character
emitPossibleLineBreak();
emitChar('<',config.getOutputFilters(),true);
break;
case ST_TAG:
case ST_TAGQUOTE:
{ // we won't finish this tag, so it's automagically rejected
String rejection = temp_buffer.toString();
temp_buffer.setLength(0);
temp_buffer.append('<');
state = ST_CHARS;
// now parse the tag contents again
if (rejection.length()>0)
parse(rejection);
running = true; // go back around for another try
} // end case
break;
case ST_PAREN:
{ // we won't finish this paren tag, so it's automagically rejected
String rejection = temp_buffer.toString();
temp_buffer.setLength(0);
temp_buffer.append('(');
state = ST_CHARS;
paren_level = 0;
// now parse the parenthesis contents again
if (rejection.length()>0)
parse(rejection);
running = true; // go back around for another try
} // end case
break;
} // end switch
} while (running); // end do
// Now close all the HTML tags that were left open.
for (int i=(tag_stack.size()-1); i>=0; i--)
{ // get each element in the tag stack and append the appropriate closing tag
Integer foo = (Integer)(tag_stack.get(i));
SimpleTag tagobj = TagRepository.tagIndexToObject(foo.intValue());
output_buffer.append(tagobj.makeClosingTag());
} // end for
// deallocate some excess crap and mark the object as finished
killState();
lines++; // there's one extra line at the end
finished = true;
} // end finish
public void reset()
{
started = false;
finished = false;
trigger_WBR = false;
state = ST_WHITESPACE;
quote_char = '\0';
columns = 0;
lines = 0;
paren_level = 0;
output_buffer = null;
killState();
// Also reset all the counters.
Iterator it = counters.values().iterator();
while (it.hasNext())
{ // reset each counter in turn
CountingRewriter cr = (CountingRewriter)(it.next());
cr.reset();
} // end while
} // end reset
public String getValue() throws NotYetFinishedException
{
if (!finished)
throw new NotYetFinishedException();
return output_buffer.toString();
} // end getValue
public int getLength() throws NotYetFinishedException
{
if (!finished)
throw new NotYetFinishedException();
return output_buffer.length();
} // end getLength
public int getLines() throws NotYetFinishedException
{
if (!finished)
throw new NotYetFinishedException();
return lines;
} // end getLines
public int getCounter(String name) throws NotYetFinishedException
{
if (!finished)
throw new NotYetFinishedException();
CountingRewriter cr = (CountingRewriter)(counters.get(name));
if (cr==null)
return 0;
else
return cr.getCount();
} // end getCounter
public Object getContextValue(String name)
{
return context_data.get(name);
} // end getContextValue
public void setContextValue(String name, Object val)
{
context_data.put(name,val);
} // end setContextValue
/*--------------------------------------------------------------------------------
* Implementations from interface HTMLCheckerBackend
*--------------------------------------------------------------------------------
*/
public String getCheckerAttrValue(String name)
{
if (name=="ANCHORTAIL")
return config.getAnchorTail();
throw new IllegalArgumentException("attribute \"" + name + "\" is not defined");
} // end getCheckerAttrValue
public void sendTagMessage(String msg)
{
if (msg=="NOBR")
{ // increment the no-break count
nobreak_count++;
return;
} // end if
if (msg=="/NOBR")
{ // decrement the no-break count
nobreak_count--;
return;
} // end if
if (msg=="WBR")
{ // trigger a word break
trigger_WBR = true;
return;
} // end if
throw new IllegalArgumentException("message \"" + msg + "\" is not defined");
} // end sendTagMessage
public Object getCheckerContextValue(String name)
{
return context_data.get(name);
} // end getCheckerContextValue
/*--------------------------------------------------------------------------------
* Implementations from interface RewriterServices
*--------------------------------------------------------------------------------
*/
public String getRewriterAttrValue(String name)
{
return getCheckerAttrValue(name);
} // end getRewriterAttrValue
public Object getRewriterContextValue(String name)
{
return context_data.get(name);
} // end getRewriterContextValue
} // end class HTMLCheckerImpl