src/main/java/net/pterodactylus/sone/template/ParserFilter.java

   1 /*
   2  * Sone - ParserFilter.java - Copyright © 2011–2012 David Roden
   3  *
   4  * This program is free software: you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation, either version 3 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 package net.pterodactylus.sone.template;
  19
  20 import java.io.IOException;
  21 import java.io.StringReader;
  22 import java.io.StringWriter;
  23 import java.io.UnsupportedEncodingException;
  24 import java.io.Writer;
  25 import java.net.URLEncoder;
  26 import java.util.ArrayList;
  27 import java.util.List;
  28 import java.util.Map;
  29
  30 import net.pterodactylus.sone.core.Core;
  31 import net.pterodactylus.sone.data.Sone;
  32 import net.pterodactylus.sone.text.FreenetLinkPart;
  33 import net.pterodactylus.sone.text.LinkPart;
  34 import net.pterodactylus.sone.text.Part;
  35 import net.pterodactylus.sone.text.PlainTextPart;
  36 import net.pterodactylus.sone.text.PostPart;
  37 import net.pterodactylus.sone.text.SonePart;
  38 import net.pterodactylus.sone.text.SoneTextParser;
  39 import net.pterodactylus.sone.text.SoneTextParserContext;
  40 import net.pterodactylus.sone.web.page.FreenetRequest;
  41 import net.pterodactylus.util.number.Numbers;
  42 import net.pterodactylus.util.template.Filter;
  43 import net.pterodactylus.util.template.Template;
  44 import net.pterodactylus.util.template.TemplateContext;
  45 import net.pterodactylus.util.template.TemplateContextFactory;
  46 import net.pterodactylus.util.template.TemplateParser;
  47
  48 /**
  49  * Filter that filters a given text through a {@link SoneTextParser}.
  50  *
  51  * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
  52  */
  53 public class ParserFilter implements Filter {
  54
  55         /** The core. */
  56         private final Core core;
  57
  58         /** The link parser. */
  59         private final SoneTextParser soneTextParser;
  60
  61         /** The template context factory. */
  62         private final TemplateContextFactory templateContextFactory;
  63
  64         /** The template for {@link PlainTextPart}s. */
  65         private static final Template plainTextTemplate = TemplateParser.parse(new StringReader("<%text|html>"));
  66
  67         /** The template for {@link FreenetLinkPart}s. */
  68         private static final Template linkTemplate = TemplateParser.parse(new StringReader("<a class=\"<%cssClass|html>\" href=\"<%link|html>\" title=\"<%title|html>\"><%text|html></a>"));
  69
  70         /**
  71          * Creates a new filter that runs its input through a {@link SoneTextParser}
  72          * .
  73          *
  74          * @param core
  75          *            The core
  76          * @param templateContextFactory
  77          *            The context factory for rendering the parts
  78          * @param soneTextParser
  79          *            The Sone text parser
  80          */
  81         public ParserFilter(Core core, TemplateContextFactory templateContextFactory, SoneTextParser soneTextParser) {
  82                 this.core = core;
  83                 this.templateContextFactory = templateContextFactory;
  84                 this.soneTextParser = soneTextParser;
  85         }
  86
  87         /**
  88          * {@inheritDoc}
  89          */
  90         @Override
  91         public Object format(TemplateContext templateContext, Object data, Map<String, Object> parameters) {
  92                 String text = String.valueOf(data);
  93                 int length = Numbers.safeParseInteger(parameters.get("length"), Numbers.safeParseInteger(templateContext.get(String.valueOf(parameters.get("length"))), -1));
  94                 int cutOffLength = Numbers.safeParseInteger(parameters.get("cut-off-length"), Numbers.safeParseInteger(templateContext.get(String.valueOf(parameters.get("cut-off-length"))), length));
  95                 Object sone = parameters.get("sone");
  96                 if (sone instanceof String) {
  97                         sone = core.getSone((String) sone, false);
  98                 }
  99                 FreenetRequest request = (FreenetRequest) templateContext.get("request");
 100                 SoneTextParserContext context = new SoneTextParserContext(request, (Sone) sone);
 101                 StringWriter parsedTextWriter = new StringWriter();
 102                 try {
 103                         Iterable<Part> parts = soneTextParser.parse(context, new StringReader(text));
 104                         if (length > -1) {
 105                                 int allPartsLength = 0;
 106                                 List<Part> shortenedParts = new ArrayList<Part>();
 107                                 for (Part part : parts) {
 108                                         if (part instanceof PlainTextPart) {
 109                                                 String longText = ((PlainTextPart) part).getText();
 110                                                 if (allPartsLength < cutOffLength) {
 111                                                         if ((allPartsLength + longText.length()) > cutOffLength) {
 112                                                                 shortenedParts.add(new PlainTextPart(longText.substring(0, cutOffLength - allPartsLength) + "…"));
 113                                                         } else {
 114                                                                 shortenedParts.add(part);
 115                                                         }
 116                                                 }
 117                                                 allPartsLength += longText.length();
 118                                         } else if (part instanceof LinkPart) {
 119                                                 if (allPartsLength < cutOffLength) {
 120                                                         shortenedParts.add(part);
 121                                                 }
 122                                                 allPartsLength += ((LinkPart) part).getText().length();
 123                                         } else {
 124                                                 if (allPartsLength < cutOffLength) {
 125                                                         shortenedParts.add(part);
 126                                                 }
 127                                         }
 128                                 }
 129                                 if (allPartsLength >= length) {
 130                                         parts = shortenedParts;
 131                                 }
 132                         }
 133                         render(parsedTextWriter, parts);
 134                 } catch (IOException ioe1) {
 135                         /* no exceptions in a StringReader or StringWriter, ignore. */
 136                 }
 137                 return parsedTextWriter.toString();
 138         }
 139
 140         //
 141         // PRIVATE METHODS
 142         //
 143
 144         /**
 145          * Renders the given parts.
 146          *
 147          * @param writer
 148          *            The writer to render the parts to
 149          * @param parts
 150          *            The parts to render
 151          */
 152         private void render(Writer writer, Iterable<Part> parts) {
 153                 for (Part part : parts) {
 154                         render(writer, part);
 155                 }
 156         }
 157
 158         /**
 159          * Renders the given part.
 160          *
 161          * @param writer
 162          *            The writer to render the part to
 163          * @param part
 164          *            The part to render
 165          */
 166         @SuppressWarnings("unchecked")
 167         private void render(Writer writer, Part part) {
 168                 if (part instanceof PlainTextPart) {
 169                         render(writer, (PlainTextPart) part);
 170                 } else if (part instanceof FreenetLinkPart) {
 171                         render(writer, (FreenetLinkPart) part);
 172                 } else if (part instanceof LinkPart) {
 173                         render(writer, (LinkPart) part);
 174                 } else if (part instanceof SonePart) {
 175                         render(writer, (SonePart) part);
 176                 } else if (part instanceof PostPart) {
 177                         render(writer, (PostPart) part);
 178                 } else if (part instanceof Iterable<?>) {
 179                         render(writer, (Iterable<Part>) part);
 180                 }
 181         }
 182
 183         /**
 184          * Renders the given plain-text part.
 185          *
 186          * @param writer
 187          *            The writer to render the part to
 188          * @param plainTextPart
 189          *            The part to render
 190          */
 191         private void render(Writer writer, PlainTextPart plainTextPart) {
 192                 TemplateContext templateContext = templateContextFactory.createTemplateContext();
 193                 templateContext.set("text", plainTextPart.getText());
 194                 plainTextTemplate.render(templateContext, writer);
 195         }
 196
 197         /**
 198          * Renders the given freenet link part.
 199          *
 200          * @param writer
 201          *            The writer to render the part to
 202          * @param freenetLinkPart
 203          *            The part to render
 204          */
 205         private void render(Writer writer, FreenetLinkPart freenetLinkPart) {
 206                 renderLink(writer, "/" + freenetLinkPart.getLink(), freenetLinkPart.getText(), freenetLinkPart.getTitle(), freenetLinkPart.isTrusted() ? "freenet-trusted" : "freenet");
 207         }
 208
 209         /**
 210          * Renders the given link part.
 211          *
 212          * @param writer
 213          *            The writer to render the part to
 214          * @param linkPart
 215          *            The part to render
 216          */
 217         private void render(Writer writer, LinkPart linkPart) {
 218                 try {
 219                         renderLink(writer, "/external-link/?_CHECKED_HTTP_=" + URLEncoder.encode(linkPart.getLink(), "UTF-8"), linkPart.getText(), linkPart.getTitle(), "internet");
 220                 } catch (UnsupportedEncodingException uee1) {
 221                         /* not possible for UTF-8. */
 222                         throw new RuntimeException("The JVM does not support UTF-8 encoding!", uee1);
 223                 }
 224         }
 225
 226         /**
 227          * Renders the given Sone part.
 228          *
 229          * @param writer
 230          *            The writer to render the part to
 231          * @param sonePart
 232          *            The part to render
 233          */
 234         private void render(Writer writer, SonePart sonePart) {
 235                 if ((sonePart.getSone() != null) && (sonePart.getSone().getName() != null)) {
 236                         renderLink(writer, "viewSone.html?sone=" + sonePart.getSone().getId(), SoneAccessor.getNiceName(sonePart.getSone()), SoneAccessor.getNiceName(sonePart.getSone()), "in-sone");
 237                 } else {
 238                         renderLink(writer, "/WebOfTrust/ShowIdentity?id=" + sonePart.getSone().getId(), sonePart.getSone().getId(), sonePart.getSone().getId(), "in-sone");
 239                 }
 240         }
 241
 242         /**
 243          * Renders the given post part.
 244          *
 245          * @param writer
 246          *            The writer to render the part to
 247          * @param postPart
 248          *            The part to render
 249          */
 250         private void render(Writer writer, PostPart postPart) {
 251                 SoneTextParser parser = new SoneTextParser(core, core);
 252                 SoneTextParserContext parserContext = new SoneTextParserContext(null, postPart.getPost().getSone());
 253                 try {
 254                         Iterable<Part> parts = parser.parse(parserContext, new StringReader(postPart.getPost().getText()));
 255                         StringBuilder excerpt = new StringBuilder();
 256                         for (Part part : parts) {
 257                                 excerpt.append(part.getText());
 258                                 if (excerpt.length() > 20) {
 259                                         int lastSpace = excerpt.lastIndexOf(" ", 20);
 260                                         if (lastSpace > -1) {
 261                                                 excerpt.setLength(lastSpace);
 262                                         } else {
 263                                                 excerpt.setLength(20);
 264                                         }
 265                                         excerpt.append("…");
 266                                         break;
 267                                 }
 268                         }
 269                         renderLink(writer, "viewPost.html?post=" + postPart.getPost().getId(), excerpt.toString(), SoneAccessor.getNiceName(postPart.getPost().getSone()), "in-sone");
 270                 } catch (IOException ioe1) {
 271                         /* StringReader shouldn’t throw. */
 272                 }
 273         }
 274
 275         /**
 276          * Renders the given link.
 277          *
 278          * @param writer
 279          *            The writer to render the link to
 280          * @param link
 281          *            The link to render
 282          * @param text
 283          *            The text of the link
 284          * @param title
 285          *            The title of the link
 286          * @param cssClass
 287          *            The CSS class of the link
 288          */
 289         private void renderLink(Writer writer, String link, String text, String title, String cssClass) {
 290                 TemplateContext templateContext = templateContextFactory.createTemplateContext();
 291                 templateContext.set("cssClass", cssClass);
 292                 templateContext.set("link", link);
 293                 templateContext.set("text", text);
 294                 templateContext.set("title", title);
 295                 linkTemplate.render(templateContext, writer);
 296         }
 297
 298 }