/*
* Sone - ParserFilter.java - Copyright © 2011–2012 David Roden
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see .
*/
package net.pterodactylus.sone.template;
import java.io.IOException;
import java.io.StringReader;
import java.io.StringWriter;
import java.io.Writer;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import net.pterodactylus.sone.core.Core;
import net.pterodactylus.sone.data.Sone;
import net.pterodactylus.sone.text.FreenetLinkPart;
import net.pterodactylus.sone.text.LinkPart;
import net.pterodactylus.sone.text.Part;
import net.pterodactylus.sone.text.PlainTextPart;
import net.pterodactylus.sone.text.PostPart;
import net.pterodactylus.sone.text.SonePart;
import net.pterodactylus.sone.text.SoneTextParser;
import net.pterodactylus.sone.text.SoneTextParserContext;
import net.pterodactylus.sone.web.page.FreenetRequest;
import net.pterodactylus.util.number.Numbers;
import net.pterodactylus.util.template.Filter;
import net.pterodactylus.util.template.Template;
import net.pterodactylus.util.template.TemplateContext;
import net.pterodactylus.util.template.TemplateContextFactory;
import net.pterodactylus.util.template.TemplateParser;
/**
* Filter that filters a given text through a {@link SoneTextParser}.
*
* @author David ‘Bombe’ Roden
*/
public class ParserFilter implements Filter {
/** The core. */
private final Core core;
/** The link parser. */
private final SoneTextParser soneTextParser;
/** The template context factory. */
private final TemplateContextFactory templateContextFactory;
/** The template for {@link PlainTextPart}s. */
private static final Template plainTextTemplate = TemplateParser.parse(new StringReader("<%text|html>"));
/** The template for {@link FreenetLinkPart}s. */
private static final Template linkTemplate = TemplateParser.parse(new StringReader("\" href=\"<%link|html>\" title=\"<%title|html>\"><%text|html>"));
/**
* Creates a new filter that runs its input through a {@link SoneTextParser}
* .
*
* @param core
* The core
* @param templateContextFactory
* The context factory for rendering the parts
* @param soneTextParser
* The Sone text parser
*/
public ParserFilter(Core core, TemplateContextFactory templateContextFactory, SoneTextParser soneTextParser) {
this.core = core;
this.templateContextFactory = templateContextFactory;
this.soneTextParser = soneTextParser;
}
/**
* {@inheritDoc}
*/
@Override
public Object format(TemplateContext templateContext, Object data, Map parameters) {
String text = String.valueOf(data);
int length = Numbers.safeParseInteger(parameters.get("length"), Numbers.safeParseInteger(templateContext.get(String.valueOf(parameters.get("length"))), -1));
int cutOffLength = Numbers.safeParseInteger(parameters.get("cut-off-length"), Numbers.safeParseInteger(templateContext.get(String.valueOf(parameters.get("cut-off-length"))), length));
Object sone = parameters.get("sone");
if (sone instanceof String) {
sone = core.getSone((String) sone, false);
}
FreenetRequest request = (FreenetRequest) templateContext.get("request");
SoneTextParserContext context = new SoneTextParserContext(request, (Sone) sone);
StringWriter parsedTextWriter = new StringWriter();
try {
Iterable parts = soneTextParser.parse(context, new StringReader(text));
if (length > -1) {
int allPartsLength = 0;
List shortenedParts = new ArrayList();
for (Part part : parts) {
if (part instanceof PlainTextPart) {
String longText = ((PlainTextPart) part).getText();
if (allPartsLength < cutOffLength) {
if ((allPartsLength + longText.length()) > cutOffLength) {
shortenedParts.add(new PlainTextPart(longText.substring(0, cutOffLength - allPartsLength) + "…"));
} else {
shortenedParts.add(part);
}
}
allPartsLength += longText.length();
} else if (part instanceof LinkPart) {
if (allPartsLength < cutOffLength) {
shortenedParts.add(part);
}
allPartsLength += ((LinkPart) part).getText().length();
} else {
if (allPartsLength < cutOffLength) {
shortenedParts.add(part);
}
}
}
if (allPartsLength >= length) {
parts = shortenedParts;
}
}
render(parsedTextWriter, parts);
} catch (IOException ioe1) {
/* no exceptions in a StringReader or StringWriter, ignore. */
}
return parsedTextWriter.toString();
}
//
// PRIVATE METHODS
//
/**
* Renders the given parts.
*
* @param writer
* The writer to render the parts to
* @param parts
* The parts to render
*/
private void render(Writer writer, Iterable parts) {
for (Part part : parts) {
render(writer, part);
}
}
/**
* Renders the given part.
*
* @param writer
* The writer to render the part to
* @param part
* The part to render
*/
@SuppressWarnings("unchecked")
private void render(Writer writer, Part part) {
if (part instanceof PlainTextPart) {
render(writer, (PlainTextPart) part);
} else if (part instanceof FreenetLinkPart) {
render(writer, (FreenetLinkPart) part);
} else if (part instanceof LinkPart) {
render(writer, (LinkPart) part);
} else if (part instanceof SonePart) {
render(writer, (SonePart) part);
} else if (part instanceof PostPart) {
render(writer, (PostPart) part);
} else if (part instanceof Iterable>) {
render(writer, (Iterable) part);
}
}
/**
* Renders the given plain-text part.
*
* @param writer
* The writer to render the part to
* @param plainTextPart
* The part to render
*/
private void render(Writer writer, PlainTextPart plainTextPart) {
TemplateContext templateContext = templateContextFactory.createTemplateContext();
templateContext.set("text", plainTextPart.getText());
plainTextTemplate.render(templateContext, writer);
}
/**
* Renders the given freenet link part.
*
* @param writer
* The writer to render the part to
* @param freenetLinkPart
* The part to render
*/
private void render(Writer writer, FreenetLinkPart freenetLinkPart) {
renderLink(writer, "/" + freenetLinkPart.getLink(), freenetLinkPart.getText(), freenetLinkPart.getTitle(), freenetLinkPart.isTrusted() ? "freenet-trusted" : "freenet");
}
/**
* Renders the given link part.
*
* @param writer
* The writer to render the part to
* @param linkPart
* The part to render
*/
private void render(Writer writer, LinkPart linkPart) {
renderLink(writer, "/?_CHECKED_HTTP_=" + linkPart.getLink(), linkPart.getText(), linkPart.getTitle(), "internet");
}
/**
* Renders the given Sone part.
*
* @param writer
* The writer to render the part to
* @param sonePart
* The part to render
*/
private void render(Writer writer, SonePart sonePart) {
if ((sonePart.getSone() != null) && (sonePart.getSone().getName() != null)) {
renderLink(writer, "viewSone.html?sone=" + sonePart.getSone().getId(), SoneAccessor.getNiceName(sonePart.getSone()), SoneAccessor.getNiceName(sonePart.getSone()), "in-sone");
} else {
renderLink(writer, "/WebOfTrust/ShowIdentity?id=" + sonePart.getSone().getId(), sonePart.getSone().getId(), sonePart.getSone().getId(), "in-sone");
}
}
/**
* Renders the given post part.
*
* @param writer
* The writer to render the part to
* @param postPart
* The part to render
*/
private void render(Writer writer, PostPart postPart) {
renderLink(writer, "viewPost.html?post=" + postPart.getPost().getId(), getExcerpt(postPart.getPost().getText(), 20), SoneAccessor.getNiceName(postPart.getPost().getSone()), "in-sone");
}
/**
* Renders the given link.
*
* @param writer
* The writer to render the link to
* @param link
* The link to render
* @param text
* The text of the link
* @param title
* The title of the link
* @param cssClass
* The CSS class of the link
*/
private void renderLink(Writer writer, String link, String text, String title, String cssClass) {
TemplateContext templateContext = templateContextFactory.createTemplateContext();
templateContext.set("cssClass", cssClass);
templateContext.set("link", link);
templateContext.set("text", text);
templateContext.set("title", title);
linkTemplate.render(templateContext, writer);
}
//
// STATIC METHODS
//
/**
* Returns up to {@code length} characters from the given text, appending
* “…” if the text is longer.
*
* @param text
* The text to get an excerpt from
* @param length
* The maximum length of the excerpt (without the ellipsis)
* @return The excerpt of the text
*/
private static String getExcerpt(String text, int length) {
String filteredText = text.replaceAll("(\r\n)+", "\r\n").replaceAll("\n+", "\n").replace("\r\n", " ").replace('\n', ' ');
if (filteredText.length() > length) {
return filteredText.substring(0, length) + "…";
}
return filteredText;
}
}