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

   1 /*
   2  * Sone - ParserFilter.java - Copyright © 2011–2015 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.Sone;
  35 import net.pterodactylus.sone.text.FreenetLinkPart;
  36 import net.pterodactylus.sone.text.LinkPart;
  37 import net.pterodactylus.sone.text.Part;
  38 import net.pterodactylus.sone.text.PlainTextPart;
  39 import net.pterodactylus.sone.text.PostPart;
  40 import net.pterodactylus.sone.text.SonePart;
  41 import net.pterodactylus.sone.text.SoneTextParser;
  42 import net.pterodactylus.sone.text.SoneTextParserContext;
  43 import net.pterodactylus.sone.web.page.FreenetRequest;
  44 import net.pterodactylus.util.template.Filter;
  45 import net.pterodactylus.util.template.Template;
  46 import net.pterodactylus.util.template.TemplateContext;
  47 import net.pterodactylus.util.template.TemplateContextFactory;
  48 import net.pterodactylus.util.template.TemplateParser;
  49
  50 /**
  51  * Filter that filters a given text through a {@link SoneTextParser}.
  52  *
  53  * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
  54  */
  55 public class ParserFilter implements Filter {
  56
  57         /** The core. */
  58         private final Core core;
  59
  60         /** The link parser. */
  61         private final SoneTextParser soneTextParser;
  62
  63         /** The template context factory. */
  64         private final TemplateContextFactory templateContextFactory;
  65
  66         /** The template for {@link PlainTextPart}s. */
  67         private static final Template plainTextTemplate = TemplateParser.parse(new StringReader("<%text|html>"));
  68
  69         /** The template for {@link FreenetLinkPart}s. */
  70         private static final Template linkTemplate = TemplateParser.parse(new StringReader("<a class=\"<%cssClass|html>\" href=\"<%link|html>\" title=\"<%title|html>\"><%text|html></a>"));
  71
  72         /**
  73          * Creates a new filter that runs its input through a {@link SoneTextParser}
  74          * .
  75          *
  76          * @param core
  77          *            The core
  78          * @param templateContextFactory
  79          *            The context factory for rendering the parts
  80          * @param soneTextParser
  81          *            The Sone text parser
  82          */
  83         public ParserFilter(Core core, TemplateContextFactory templateContextFactory, SoneTextParser soneTextParser) {
  84                 this.core = core;
  85                 this.templateContextFactory = templateContextFactory;
  86                 this.soneTextParser = soneTextParser;
  87         }
  88
  89         /**
  90          * {@inheritDoc}
  91          */
  92         @Override
  93         public Object format(TemplateContext templateContext, Object data, Map<String, Object> parameters) {
  94                 String text = valueOf(data);
  95                 int length = parseInt(valueOf(parameters.get("length")), -1);
  96                 int cutOffLength = parseInt(valueOf(parameters.get("cut-off-length")), length);
  97                 Object sone = parameters.get("sone");
  98                 if (sone instanceof String) {
  99                         sone = core.getSone((String) sone).orNull();
 100                 }
 101                 FreenetRequest request = (FreenetRequest) templateContext.get("request");
 102                 SoneTextParserContext context = new SoneTextParserContext(request, (Sone) sone);
 103                 StringWriter parsedTextWriter = new StringWriter();
 104                 Iterable<Part> parts = soneTextParser.parse(context, text);
 105                 if (length > -1) {
 106                         int allPartsLength = 0;
 107                         List<Part> shortenedParts = new ArrayList<Part>();
 108                         for (Part part : parts) {
 109                                 if (part instanceof PlainTextPart) {
 110                                         String longText = part.getText();
 111                                         if (allPartsLength < cutOffLength) {
 112                                                 if ((allPartsLength + longText.length()) > cutOffLength) {
 113                                                         shortenedParts.add(new PlainTextPart(longText.substring(0, cutOffLength - allPartsLength) + "…"));
 114                                                 } else {
 115                                                         shortenedParts.add(part);
 116                                                 }
 117                                         }
 118                                         allPartsLength += longText.length();
 119                                 } else if (part instanceof LinkPart) {
 120                                         if (allPartsLength < cutOffLength) {
 121                                                 shortenedParts.add(part);
 122                                         }
 123                                         allPartsLength += part.getText().length();
 124                                 } else {
 125                                         if (allPartsLength < cutOffLength) {
 126                                                 shortenedParts.add(part);
 127                                         }
 128                                 }
 129                         }
 130                         if (allPartsLength >= length) {
 131                                 parts = shortenedParts;
 132                         }
 133                 }
 134                 render(parsedTextWriter, parts);
 135                 return parsedTextWriter.toString();
 136         }
 137
 138         //
 139         // PRIVATE METHODS
 140         //
 141
 142         /**
 143          * Renders the given parts.
 144          *
 145          * @param writer
 146          *            The writer to render the parts to
 147          * @param parts
 148          *            The parts to render
 149          */
 150         private void render(Writer writer, Iterable<Part> parts) {
 151                 for (Part part : parts) {
 152                         render(writer, part);
 153                 }
 154         }
 155
 156         /**
 157          * Renders the given part.
 158          *
 159          * @param writer
 160          *            The writer to render the part to
 161          * @param part
 162          *            The part to render
 163          */
 164         @SuppressWarnings("unchecked")
 165         private void render(Writer writer, Part part) {
 166                 if (part instanceof PlainTextPart) {
 167                         render(writer, (PlainTextPart) part);
 168                 } else if (part instanceof FreenetLinkPart) {
 169                         render(writer, (FreenetLinkPart) part);
 170                 } else if (part instanceof LinkPart) {
 171                         render(writer, (LinkPart) part);
 172                 } else if (part instanceof SonePart) {
 173                         render(writer, (SonePart) part);
 174                 } else if (part instanceof PostPart) {
 175                         render(writer, (PostPart) part);
 176                 } else if (part instanceof Iterable<?>) {
 177                         render(writer, (Iterable<Part>) part);
 178                 }
 179         }
 180
 181         /**
 182          * Renders the given plain-text part.
 183          *
 184          * @param writer
 185          *            The writer to render the part to
 186          * @param plainTextPart
 187          *            The part to render
 188          */
 189         private void render(Writer writer, PlainTextPart plainTextPart) {
 190                 TemplateContext templateContext = templateContextFactory.createTemplateContext();
 191                 templateContext.set("text", plainTextPart.getText());
 192                 plainTextTemplate.render(templateContext, writer);
 193         }
 194
 195         /**
 196          * Renders the given freenet link part.
 197          *
 198          * @param writer
 199          *            The writer to render the part to
 200          * @param freenetLinkPart
 201          *            The part to render
 202          */
 203         private void render(Writer writer, FreenetLinkPart freenetLinkPart) {
 204                 renderLink(writer, "/" + freenetLinkPart.getLink(), freenetLinkPart.getText(), freenetLinkPart.getTitle(), freenetLinkPart.isTrusted() ? "freenet-trusted" : "freenet");
 205         }
 206
 207         /**
 208          * Renders the given link part.
 209          *
 210          * @param writer
 211          *            The writer to render the part to
 212          * @param linkPart
 213          *            The part to render
 214          */
 215         private void render(Writer writer, LinkPart linkPart) {
 216                 try {
 217                         renderLink(writer, "/external-link/?_CHECKED_HTTP_=" + URLEncoder.encode(linkPart.getLink(), "UTF-8"), linkPart.getText(), linkPart.getTitle(), "internet");
 218                 } catch (UnsupportedEncodingException uee1) {
 219                         /* not possible for UTF-8. */
 220                         throw new RuntimeException("The JVM does not support UTF-8 encoding!", uee1);
 221                 }
 222         }
 223
 224         /**
 225          * Renders the given Sone part.
 226          *
 227          * @param writer
 228          *            The writer to render the part to
 229          * @param sonePart
 230          *            The part to render
 231          */
 232         private void render(Writer writer, SonePart sonePart) {
 233                 if ((sonePart.getSone() != null) && (sonePart.getSone().getName() != null)) {
 234                         renderLink(writer, "viewSone.html?sone=" + sonePart.getSone().getId(), SoneAccessor.getNiceName(sonePart.getSone()), SoneAccessor.getNiceName(sonePart.getSone()), "in-sone");
 235                 } else {
 236                         renderLink(writer, "/WebOfTrust/ShowIdentity?id=" + sonePart.getSone().getId(), sonePart.getSone().getId(), sonePart.getSone().getId(), "in-sone");
 237                 }
 238         }
 239
 240         /**
 241          * Renders the given post part.
 242          *
 243          * @param writer
 244          *            The writer to render the part to
 245          * @param postPart
 246          *            The part to render
 247          */
 248         private void render(Writer writer, PostPart postPart) {
 249                 SoneTextParser parser = new SoneTextParser(core, core);
 250                 SoneTextParserContext parserContext = new SoneTextParserContext(null, postPart.getPost().getSone());
 251                 Iterable<Part> parts = parser.parse(parserContext, postPart.getPost().getText());
 252                 StringBuilder excerpt = new StringBuilder();
 253                 for (Part part : parts) {
 254                         excerpt.append(part.getText());
 255                         if (excerpt.length() > 20) {
 256                                 int lastSpace = excerpt.lastIndexOf(" ", 20);
 257                                 if (lastSpace > -1) {
 258                                         excerpt.setLength(lastSpace);
 259                                 } else {
 260                                         excerpt.setLength(20);
 261                                 }
 262                                 excerpt.append("…");
 263                                 break;
 264                         }
 265                 }
 266                 renderLink(writer, "viewPost.html?post=" + postPart.getPost().getId(), excerpt.toString(), SoneAccessor.getNiceName(postPart.getPost().getSone()), "in-sone");
 267         }
 268
 269         /**
 270          * Renders the given link.
 271          *
 272          * @param writer
 273          *            The writer to render the link to
 274          * @param link
 275          *            The link to render
 276          * @param text
 277          *            The text of the link
 278          * @param title
 279          *            The title of the link
 280          * @param cssClass
 281          *            The CSS class of the link
 282          */
 283         private void renderLink(Writer writer, String link, String text, String title, String cssClass) {
 284                 TemplateContext templateContext = templateContextFactory.createTemplateContext();
 285                 templateContext.set("cssClass", cssClass);
 286                 templateContext.set("link", link);
 287                 templateContext.set("text", text);
 288                 templateContext.set("title", title);
 289                 linkTemplate.render(templateContext, writer);
 290         }
 291
 292 }