package com.nwalsh.saxon;
import java.util.Stack;
import java.util.StringTokenizer;
import org.xml.sax.*;
import org.w3c.dom.*;
import javax.xml.transform.TransformerException;
import com.icl.saxon.Controller;
import com.icl.saxon.om.NamePool;
import com.icl.saxon.output.Emitter;
import com.icl.saxon.tree.AttributeCollection;
/**
* <p>Saxon extension to decorate a result tree fragment with callouts.</p>
*
* <p>$Id: CalloutEmitter.java,v 1.2 2002/03/21 13:27:51 nwalsh Exp $</p>
*
* <p>Copyright (C) 2000 Norman Walsh.</p>
*
* <p>This class provides the guts of a
* <a href="http://users.iclway.co.uk/mhkay/saxon/">Saxon 6.*</a>
* implementation of callouts for verbatim environments. (It is used
* by the Verbatim class.)</p>
*
* <p>The general design is this: the stylesheets construct a result tree
* fragment for some verbatim environment. The Verbatim class initializes
* a CalloutEmitter with information about the callouts that should be applied
* to the verbatim environment in question. Then the result tree fragment
* is "replayed" through the CalloutEmitter; the CalloutEmitter builds a
* new result tree fragment from this event stream, decorated with callouts,
* and that is returned.</p>
*
* <p><b>Change Log:</b></p>
* <dl>
* <dt>1.0</dt>
* <dd><p>Initial release.</p></dd>
* </dl>
*
* @see Verbatim
*
* @author Norman Walsh
* <a href="mailto:ndw@nwalsh.com">ndw@nwalsh.com</a>
*
* @version $Id: CalloutEmitter.java,v 1.2 2002/03/21 13:27:51 nwalsh Exp $
*
*/
public class CalloutEmitter extends CopyEmitter {
/** A stack for the preserving information about open elements. */
protected Stack elementStack = null;
/** A stack for holding information about temporarily closed elements. */
protected Stack tempStack = null;
/** Is the next element absolutely the first element in the fragment? */
protected boolean firstElement = false;
/** The FO namespace name. */
protected static String foURI = "http://www.w3.org/1999/XSL/Format";
/** The XHTML namespace name. */
protected static String xhURI = "http://www.w3.org/1999/xhtml";
/** The default column for callouts that specify only a line. */
protected int defaultColumn = 60;
/** Is the stylesheet currently running an FO stylesheet? */
protected boolean foStylesheet = false;
/** The current line number. */
private static int lineNumber = 0;
/** The current column number. */
private static int colNumber = 0;
/** The (sorted) array of callouts obtained from the areaspec. */
private static Callout callout[] = null;
/** The number of callouts in the callout array. */
private static int calloutCount = 0;
/** A pointer used to keep track of our position in the callout array. */
private static int calloutPos = 0;
/** The FormatCallout object to use for formatting callouts. */
private static FormatCallout fCallout = null;
/** <p>Constructor for the CalloutEmitter.</p>
*
* @param namePool The name pool to use for constructing elements and attributes.
* @param graphicsPath The path to callout number graphics.
* @param graphicsExt The extension for callout number graphics.
* @param graphicsMax The largest callout number that can be represented as a graphic.
* @param defaultColumn The default column for callouts.
* @param foStylesheet Is this an FO stylesheet?
*/
public CalloutEmitter(Controller controller,
NamePool namePool,
int defaultColumn,
boolean foStylesheet,
FormatCallout fCallout) {
super(controller, namePool);
elementStack = new Stack();
firstElement = true;
this.defaultColumn = defaultColumn;
this.foStylesheet = foStylesheet;
this.fCallout = fCallout;
}
/**
* <p>Examine the areaspec and determine the number and position of
* callouts.</p>
*
* <p>The <code><a href="http://docbook.org/tdg/html/areaspec.html">areaspecNodeSet</a></code>
* is examined and a sorted list of the callouts is constructed.</p>
*
* <p>This data structure is used to augment the result tree fragment
* with callout bullets.</p>
*
* @param areaspecNodeSet The source document <areaspec> element.
*
*/
public void setupCallouts (NodeList areaspecNodeList) {
callout = new Callout[10];
calloutCount = 0;
calloutPos = 0;
lineNumber = 1;
colNumber = 1;
// First we walk through the areaspec to calculate the position
// of the callouts
// <areaspec>
// <areaset id="ex.plco.const" coords="">
// <area id="ex.plco.c1" coords="4"/>
// <area id="ex.plco.c2" coords="8"/>
// </areaset>
// <area id="ex.plco.ret" coords="12"/>
// <area id="ex.plco.dest" coords="12"/>
// </areaspec>
int pos = 0;
int coNum = 0;
boolean inAreaSet = false;
Node areaspec = areaspecNodeList.item(0);
NodeList children = areaspec.getChildNodes();
for (int count = 0; count < children.getLength(); count++) {
Node node = children.item(count);
if (node.getNodeType() == Node.ELEMENT_NODE) {
if (node.getNodeName().equalsIgnoreCase("areaset")) {
coNum++;
NodeList areas = node.getChildNodes();
for (int acount = 0; acount < areas.getLength(); acount++) {
Node area = areas.item(acount);
if (area.getNodeType() == Node.ELEMENT_NODE) {
if (area.getNodeName().equalsIgnoreCase("area")) {
addCallout(coNum, area, defaultColumn);
} else {
System.out.println("Unexpected element in areaset: "
+ area.getNodeName());
}
}
}
} else if (node.getNodeName().equalsIgnoreCase("area")) {
coNum++;
addCallout(coNum, node, defaultColumn);
} else {
System.out.println("Unexpected element in areaspec: "
+ node.getNodeName());
}
}
}
// Now sort them
java.util.Arrays.sort(callout, 0, calloutCount);
}
/** Process characters. */
public void characters(char[] chars, int start, int len)
throws TransformerException {
// If we hit characters, then there's no first element...
firstElement = false;
if (lineNumber == 0) {
// if there are any text nodes, there's at least one line
lineNumber++;
colNumber = 1;
}
// Walk through the text node looking for callout positions
char[] newChars = new char[len];
int pos = 0;
for (int count = start; count < start+len; count++) {
if (calloutPos < calloutCount
&& callout[calloutPos].getLine() == lineNumber
&& callout[calloutPos].getColumn() == colNumber) {
if (pos > 0) {
rtfEmitter.characters(newChars, 0, pos);
pos = 0;
}
closeOpenElements(rtfEmitter);
while (calloutPos < calloutCount
&& callout[calloutPos].getLine() == lineNumber
&& callout[calloutPos].getColumn() == colNumber) {
fCallout.formatCallout(rtfEmitter, callout[calloutPos]);
calloutPos++;
}
openClosedElements(rtfEmitter);
}
if (chars[count] == '\n') {
// What if we need to pad this line?
if (calloutPos < calloutCount
&& callout[calloutPos].getLine() == lineNumber
&& callout[calloutPos].getColumn() > colNumber) {
if (pos > 0) {
rtfEmitter.characters(newChars, 0, pos);
pos = 0;
}
closeOpenElements(rtfEmitter);
while (calloutPos < calloutCount
&& callout[calloutPos].getLine() == lineNumber
&& callout[calloutPos].getColumn() > colNumber) {
formatPad(callout[calloutPos].getColumn() - colNumber);
colNumber = callout[calloutPos].getColumn();
while (calloutPos < calloutCount
&& callout[calloutPos].getLine() == lineNumber
&& callout[calloutPos].getColumn() == colNumber) {
fCallout.formatCallout(rtfEmitter, callout[calloutPos]);
calloutPos++;
}
}
openClosedElements(rtfEmitter);
}
lineNumber++;
colNumber = 1;
} else {
colNumber++;
}
newChars[pos++] = chars[count];
}
if (pos > 0) {
rtfEmitter.characters(newChars, 0, pos);
}
}
/**
* <p>Add blanks to the result tree fragment.</p>
*
* <p>This method adds <tt>numBlanks</tt> to the result tree fragment.
* It's used to pad lines when callouts occur after the last existing
* characater in a line.</p>
*
* @param numBlanks The number of blanks to add.
*/
protected void formatPad(int numBlanks) {
char chars[] = new char[numBlanks];
for (int count = 0; count < numBlanks; count++) {
chars[count] = ' ';
}
try {
rtfEmitter.characters(chars, 0, numBlanks);
} catch (TransformerException e) {
System.out.println("Transformer Exception in formatPad");
}
}
/**
* <p>Add a callout to the global callout array</p>
*
* <p>This method examines a callout <tt>area</tt> and adds it to
* the global callout array if it can be interpreted.</p>
*
* <p>Only the <tt>linecolumn</tt> and <tt>linerange</tt> units are
* supported. If no unit is specifed, <tt>linecolumn</tt> is assumed.
* If only a line is specified, the callout decoration appears in
* the <tt>defaultColumn</tt>.</p>
*
* @param coNum The callout number.
* @param node The <tt>area</tt>.
* @param defaultColumn The default column for callouts.
*/
protected void addCallout (int coNum,
Node node,
int defaultColumn) {
Element area = (Element) node;
String units = null;
String coords = null;
if (area.hasAttribute("units")) {
units = area.getAttribute("units");
}
if (area.hasAttribute("coords")) {
coords = area.getAttribute("coords");
}
if (units != null
&& !units.equalsIgnoreCase("linecolumn")
&& !units.equalsIgnoreCase("linerange")) {
System.out.println("Only linecolumn and linerange units are supported");
return;
}
if (coords == null) {
System.out.println("Coords must be specified");
return;
}
// Now let's see if we can interpret the coordinates...
StringTokenizer st = new StringTokenizer(coords);
int tokenCount = 0;
int c1 = 0;
int c2 = 0;
while (st.hasMoreTokens()) {
tokenCount++;
if (tokenCount > 2) {
System.out.println("Unparseable coordinates");
return;
}
try {
String token = st.nextToken();
int coord = Integer.parseInt(token);
c2 = coord;
if (tokenCount == 1) {
c1 = coord;
}
} catch (NumberFormatException e) {
System.out.println("Unparseable coordinate");
return;
}
}
// Make sure we aren't going to blow past the end of our array
if (calloutCount == callout.length) {
Callout bigger[] = new Callout[calloutCount+10];
for (int count = 0; count < callout.length; count++) {
bigger[count] = callout[count];
}
callout = bigger;
}
// Ok, add the callout
if (tokenCount == 2) {
if (units != null && units.equalsIgnoreCase("linerange")) {
for (int count = c1; count <= c2; count++) {
callout[calloutCount++] = new Callout(coNum, area,
count, defaultColumn);
}
} else {
// assume linecolumn
callout[calloutCount++] = new Callout(coNum, area, c1, c2);
}
} else {
// if there's only one number, assume it's the line
callout[calloutCount++] = new Callout(coNum, area, c1, defaultColumn);
}
}
/** Process end element events. */
public void endElement(int nameCode)
throws TransformerException {
if (!elementStack.empty()) {
// if we didn't push the very first element (an fo:block or
// pre or div surrounding the whole block), then the stack will
// be empty when we get to the end of the first element...
elementStack.pop();
}
rtfEmitter.endElement(nameCode);
}
/** Process start element events. */
public void startElement(int nameCode,
org.xml.sax.Attributes attributes,
int[] namespaces,
int nscount)
throws TransformerException {
if (!skipThisElement(nameCode)) {
StartElementInfo sei = new StartElementInfo(nameCode, attributes,
namespaces, nscount);
elementStack.push(sei);
}
firstElement = false;
rtfEmitter.startElement(nameCode, attributes, namespaces, nscount);
}
/**
* <p>Protect the outer-most block wrapper.</p>
*
* <p>Open elements in the result tree fragment are closed and reopened
* around callouts (so that callouts don't appear inside links or other
* environments). But if the result tree fragment is a single block
* (a div or pre in HTML, an fo:block in FO), that outer-most block is
* treated specially.</p>
*
* <p>This method returns true if the element in question is that
* outermost block.</p>
*
* @param nameCode The name code for the element
*
* @return True if the element is the outer-most block, false otherwise.
*/
protected boolean skipThisElement(int nameCode) {
// FIXME: This is such a gross hack...
if (firstElement) {
int thisFingerprint = namePool.getFingerprint(nameCode);
int foBlockFingerprint = namePool.getFingerprint(foURI, "block");
int htmlPreFingerprint = namePool.getFingerprint("", "pre");
int htmlDivFingerprint = namePool.getFingerprint("", "div");
int xhtmlPreFingerprint = namePool.getFingerprint(xhURI, "pre");
int xhtmlDivFingerprint = namePool.getFingerprint(xhURI, "div");
if ((foStylesheet && thisFingerprint == foBlockFingerprint)
|| (!foStylesheet && (thisFingerprint == htmlPreFingerprint
|| thisFingerprint == htmlDivFingerprint
|| thisFingerprint == xhtmlPreFingerprint
|| thisFingerprint == xhtmlDivFingerprint))) {
// Don't push the outer-most wrapping div, pre, or fo:block
return true;
}
}
return false;
}
private void closeOpenElements(Emitter rtfEmitter)
throws TransformerException {
// Close all the open elements...
tempStack = new Stack();
while (!elementStack.empty()) {
StartElementInfo elem = (StartElementInfo) elementStack.pop();
rtfEmitter.endElement(elem.getNameCode());
tempStack.push(elem);
}
}
private void openClosedElements(Emitter rtfEmitter)
throws TransformerException {
// Now "reopen" the elements that we closed...
while (!tempStack.empty()) {
StartElementInfo elem = (StartElementInfo) tempStack.pop();
AttributeCollection attr = (AttributeCollection) elem.getAttributes();
AttributeCollection newAttr = new AttributeCollection(namePool);
for (int acount = 0; acount < attr.getLength(); acount++) {
String localName = attr.getLocalName(acount);
int nameCode = attr.getNameCode(acount);
String type = attr.getType(acount);
String value = attr.getValue(acount);
String uri = attr.getURI(acount);
String prefix = "";
if (localName.indexOf(':') > 0) {
prefix = localName.substring(0, localName.indexOf(':'));
localName = localName.substring(localName.indexOf(':')+1);
}
if (uri.equals("")
&& ((foStylesheet
&& localName.equals("id"))
|| (!foStylesheet
&& (localName.equals("id")
|| localName.equals("name"))))) {
// skip this attribute
} else {
newAttr.addAttribute(prefix, uri, localName, type, value);
}
}
rtfEmitter.startElement(elem.getNameCode(),
newAttr,
elem.getNamespaces(),
elem.getNSCount());
elementStack.push(elem);
}
}
/**
* <p>A private class for maintaining the information required to call
* the startElement method.</p>
*
* <p>In order to close and reopen elements, information about those
* elements has to be maintained. This class is just the little record
* that we push on the stack to keep track of that info.</p>
*/
private class StartElementInfo {
private int _nameCode;
org.xml.sax.Attributes _attributes;
int[] _namespaces;
int _nscount;
public StartElementInfo(int nameCode,
org.xml.sax.Attributes attributes,
int[] namespaces,
int nscount) {
_nameCode = nameCode;
_attributes = attributes;
_namespaces = namespaces;
_nscount = nscount;
}
public int getNameCode() {
return _nameCode;
}
public org.xml.sax.Attributes getAttributes() {
return _attributes;
}
public int[] getNamespaces() {
return _namespaces;
}
public int getNSCount() {
return _nscount;
}
}
}