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

   1 /*
   2  * Sone - ParserFilter.java - Copyright © 2011–2013 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 static java.lang.String.valueOf;
  21 import static net.pterodactylus.sone.utils.NumberParsers.parseInt;
  22
  23 import java.io.IOException;
  24 import java.io.StringReader;
  25 import java.io.StringWriter;
  26 import java.io.UnsupportedEncodingException;
  27 import java.io.Writer;
  28 import java.net.URLEncoder;
  29 import java.util.ArrayList;
  30 import java.util.List;
  31 import java.util.Map;
  32
  33 import net.pterodactylus.sone.core.Core;
  34 import net.pterodactylus.sone.data.Album;
  35 import net.pterodactylus.sone.data.Sone;
  36 import net.pterodactylus.sone.text.AlbumPart;
  37 import net.pterodactylus.sone.text.FreenetLinkPart;
  38 import net.pterodactylus.sone.text.LinkPart;
  39 import net.pterodactylus.sone.text.Part;
  40 import net.pterodactylus.sone.text.PlainTextPart;
  41 import net.pterodactylus.sone.text.PostPart;
  42 import net.pterodactylus.sone.text.SonePart;
  43 import net.pterodactylus.sone.text.SoneTextParser;
  44 import net.pterodactylus.sone.text.SoneTextParserContext;
  45 import net.pterodactylus.sone.web.page.FreenetRequest;
  46 import net.pterodactylus.util.template.Filter;
  47 import net.pterodactylus.util.template.Template;
  48 import net.pterodactylus.util.template.TemplateContext;
  49 import net.pterodactylus.util.template.TemplateContextFactory;
  50 import net.pterodactylus.util.template.TemplateParser;
  51
  52 /**
  53  * Filter that filters a given text through a {@link SoneTextParser}.
  54  *
  55  * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
  56  */
  57 public class ParserFilter implements Filter {
  58
  59         /** The core. */
  60         private final Core core;
  61
  62         /** The link parser. */
  63         private final SoneTextParser soneTextParser;
  64
  65         /** The template context factory. */
  66         private final TemplateContextFactory templateContextFactory;
  67
  68         /** The template for {@link PlainTextPart}s. */
  69         private static final Template plainTextTemplate = TemplateParser.parse(new StringReader("<%text|html>"));
  70
  71         /** The template for {@link FreenetLinkPart}s. */
  72         private static final Template linkTemplate = TemplateParser.parse(new StringReader("<a class=\"<%cssClass|html>\" href=\"<%link|html>\" title=\"<%title|html>\"><%text|html></a>"));
  73
  74         /**
  75          * Creates a new filter that runs its input through a {@link SoneTextParser}
  76          * .
  77          *
  78          * @param core
  79          *            The core
  80          * @param templateContextFactory
  81          *            The context factory for rendering the parts
  82          * @param soneTextParser
  83          *            The Sone text parser
  84          */
  85         public ParserFilter(Core core, TemplateContextFactory templateContextFactory, SoneTextParser soneTextParser) {
  86                 this.core = core;
  87                 this.templateContextFactory = templateContextFactory;
  88                 this.soneTextParser = soneTextParser;
  89         }
  90
  91         /**
  92          * {@inheritDoc}
  93          */
  94         @Override
  95         public Object format(TemplateContext templateContext, Object data, Map<String, Object> parameters) {
  96                 String text = valueOf(data);
  97                 int length = parseInt(valueOf(parameters.get("length")), -1);
  98                 int cutOffLength = parseInt(valueOf(parameters.get("cut-off-length")), length);
  99                 Object sone = parameters.get("sone");
 100                 if (sone instanceof String) {
 101                         sone = core.getSone((String) sone).orNull();
 102                 }
 103                 FreenetRequest request = (FreenetRequest) templateContext.get("request");
 104                 SoneTextParserContext context = new SoneTextParserContext(request, (Sone) sone);
 105                 StringWriter parsedTextWriter = new StringWriter();
 106                 try {
 107                         Iterable<Part> parts = soneTextParser.parse(context, new StringReader(text));
 108                         if (length > -1) {
 109                                 int allPartsLength = 0;
 110                                 List<Part> shortenedParts = new ArrayList<Part>();
 111                                 for (Part part : parts) {
 112                                         if (part instanceof PlainTextPart) {
 113                                                 String longText = ((PlainTextPart) part).getText();
 114                                                 if (allPartsLength < cutOffLength) {
 115                                                         if ((allPartsLength + longText.length()) > cutOffLength) {
 116                                                                 shortenedParts.add(new PlainTextPart(longText.substring(0, cutOffLength - allPartsLength) + "…"));
 117                                                         } else {
 118                                                                 shortenedParts.add(part);
 119                                                         }
 120                                                 }
 121                                                 allPartsLength += longText.length();
 122                                         } else if (part instanceof LinkPart) {
 123                                                 if (allPartsLength < cutOffLength) {
 124                                                         shortenedParts.add(part);
 125                                                 }
 126                                                 allPartsLength += ((LinkPart) part).getText().length();
 127                                         } else {
 128                                                 if (allPartsLength < cutOffLength) {
 129                                                         shortenedParts.add(part);
 130                                                 }
 131                                         }
 132                                 }
 133                                 if (allPartsLength >= length) {
 134                                         parts = shortenedParts;
 135                                 }
 136                         }
 137                         render(parsedTextWriter, parts);
 138                 } catch (IOException ioe1) {
 139                         /* no exceptions in a StringReader or StringWriter, ignore. */
 140                 }
 141                 return parsedTextWriter.toString();
 142         }
 143
 144         //
 145         // PRIVATE METHODS
 146         //
 147
 148         /**
 149          * Renders the given parts.
 150          *
 151          * @param writer
 152          *            The writer to render the parts to
 153          * @param parts
 154          *            The parts to render
 155          */
 156         private void render(Writer writer, Iterable<Part> parts) {
 157                 for (Part part : parts) {
 158                         render(writer, part);
 159                 }
 160         }
 161
 162         /**
 163          * Renders the given part.
 164          *
 165          * @param writer
 166          *            The writer to render the part to
 167          * @param part
 168          *            The part to render
 169          */
 170         @SuppressWarnings("unchecked")
 171         private void render(Writer writer, Part part) {
 172                 if (part instanceof PlainTextPart) {
 173                         render(writer, (PlainTextPart) part);
 174                 } else if (part instanceof FreenetLinkPart) {
 175                         render(writer, (FreenetLinkPart) part);
 176                 } else if (part instanceof LinkPart) {
 177                         render(writer, (LinkPart) part);
 178                 } else if (part instanceof SonePart) {
 179                         render(writer, (SonePart) part);
 180                 } else if (part instanceof PostPart) {
 181                         render(writer, (PostPart) part);
 182                 } else if (part instanceof AlbumPart) {
 183                         render(writer, (AlbumPart) part);
 184                 } else if (part instanceof Iterable<?>) {
 185                         render(writer, (Iterable<Part>) part);
 186                 }
 187         }
 188
 189         /**
 190          * Renders the given plain-text part.
 191          *
 192          * @param writer
 193          *            The writer to render the part to
 194          * @param plainTextPart
 195          *            The part to render
 196          */
 197         private void render(Writer writer, PlainTextPart plainTextPart) {
 198                 TemplateContext templateContext = templateContextFactory.createTemplateContext();
 199                 templateContext.set("text", plainTextPart.getText());
 200                 plainTextTemplate.render(templateContext, writer);
 201         }
 202
 203         /**
 204          * Renders the given freenet link part.
 205          *
 206          * @param writer
 207          *            The writer to render the part to
 208          * @param freenetLinkPart
 209          *            The part to render
 210          */
 211         private void render(Writer writer, FreenetLinkPart freenetLinkPart) {
 212                 renderLink(writer, "/" + freenetLinkPart.getLink(), freenetLinkPart.getText(), freenetLinkPart.getTitle(), freenetLinkPart.isTrusted() ? "freenet-trusted" : "freenet");
 213         }
 214
 215         /**
 216          * Renders the given link part.
 217          *
 218          * @param writer
 219          *            The writer to render the part to
 220          * @param linkPart
 221          *            The part to render
 222          */
 223         private void render(Writer writer, LinkPart linkPart) {
 224                 try {
 225                         renderLink(writer, "/external-link/?_CHECKED_HTTP_=" + URLEncoder.encode(linkPart.getLink(), "UTF-8"), linkPart.getText(), linkPart.getTitle(), "internet");
 226                 } catch (UnsupportedEncodingException uee1) {
 227                         /* not possible for UTF-8. */
 228                         throw new RuntimeException("The JVM does not support UTF-8 encoding!", uee1);
 229                 }
 230         }
 231
 232         /**
 233          * Renders the given Sone part.
 234          *
 235          * @param writer
 236          *            The writer to render the part to
 237          * @param sonePart
 238          *            The part to render
 239          */
 240         private void render(Writer writer, SonePart sonePart) {
 241                 if ((sonePart.getSone() != null) && (sonePart.getSone().getName() != null)) {
 242                         renderLink(writer, "viewSone.html?sone=" + sonePart.getSone().getId(), SoneAccessor.getNiceName(sonePart.getSone()), SoneAccessor.getNiceName(sonePart.getSone()), "in-sone");
 243                 } else {
 244                         renderLink(writer, "/WebOfTrust/ShowIdentity?id=" + sonePart.getSone().getId(), sonePart.getSone().getId(), sonePart.getSone().getId(), "in-sone");
 245                 }
 246         }
 247
 248         /**
 249          * Renders the given post part.
 250          *
 251          * @param writer
 252          *            The writer to render the part to
 253          * @param postPart
 254          *            The part to render
 255          */
 256         private void render(Writer writer, PostPart postPart) {
 257                 SoneTextParser parser = new SoneTextParser(core, core, core);
 258                 SoneTextParserContext parserContext = new SoneTextParserContext(null, postPart.getPost().getSone());
 259                 try {
 260                         Iterable<Part> parts = parser.parse(parserContext, new StringReader(postPart.getPost().getText()));
 261                         StringBuilder excerpt = new StringBuilder();
 262                         for (Part part : parts) {
 263                                 excerpt.append(part.getText());
 264                                 if (excerpt.length() > 20) {
 265                                         int lastSpace = excerpt.lastIndexOf(" ", 20);
 266                                         if (lastSpace > -1) {
 267                                                 excerpt.setLength(lastSpace);
 268                                         } else {
 269                                                 excerpt.setLength(20);
 270                                         }
 271                                         excerpt.append("…");
 272                                         break;
 273                                 }
 274                         }
 275                         renderLink(writer, "viewPost.html?post=" + postPart.getPost().getId(), excerpt.toString(),
 276                                 SoneAccessor.getNiceName(postPart.getPost().getSone()), postPart.usesDeprecatedLink() ? "internet" : "in-sone");
 277                 } catch (IOException ioe1) {
 278                         /* StringReader shouldn’t throw. */
 279                 }
 280         }
 281
 282         private void render(Writer writer, AlbumPart albumPart) {
 283                 Album album = albumPart.getAlbum();
 284                 renderLink(writer, String.format("imageBrowser.html?album=%s", album.getId()), album.getTitle(), album.getDescription(), "in-sone");
 285         }
 286
 287         /**
 288          * Renders the given link.
 289          *
 290          * @param writer
 291          *            The writer to render the link to
 292          * @param link
 293          *            The link to render
 294          * @param text
 295          *            The text of the link
 296          * @param title
 297          *            The title of the link
 298          * @param cssClass
 299          *            The CSS class of the link
 300          */
 301         private void renderLink(Writer writer, String link, String text, String title, String cssClass) {
 302                 TemplateContext templateContext = templateContextFactory.createTemplateContext();
 303                 templateContext.set("cssClass", cssClass);
 304                 templateContext.set("link", link);
 305                 templateContext.set("text", text);
 306                 templateContext.set("title", title);
 307                 linkTemplate.render(templateContext, writer);
 308         }
 309
 310 }