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

   1 /*
   2  * Sone - ParserFilter.java - Copyright © 2011–2016 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.StringReader;
  24 import java.io.StringWriter;
  25 import java.io.UnsupportedEncodingException;
  26 import java.io.Writer;
  27 import java.net.URLEncoder;
  28 import java.util.ArrayList;
  29 import java.util.List;
  30 import java.util.Map;
  31
  32 import net.pterodactylus.sone.core.Core;
  33 import net.pterodactylus.sone.data.Sone;
  34 import net.pterodactylus.sone.text.FreenetLinkPart;
  35 import net.pterodactylus.sone.text.LinkPart;
  36 import net.pterodactylus.sone.text.Part;
  37 import net.pterodactylus.sone.text.PlainTextPart;
  38 import net.pterodactylus.sone.text.PostPart;
  39 import net.pterodactylus.sone.text.SonePart;
  40 import net.pterodactylus.sone.text.SoneTextParser;
  41 import net.pterodactylus.sone.text.SoneTextParserContext;
  42 import net.pterodactylus.sone.web.page.FreenetRequest;
  43 import net.pterodactylus.util.template.Filter;
  44 import net.pterodactylus.util.template.Template;
  45 import net.pterodactylus.util.template.TemplateContext;
  46 import net.pterodactylus.util.template.TemplateContextFactory;
  47 import net.pterodactylus.util.template.TemplateParser;
  48
  49 /**
  50  * Filter that filters a given text through a {@link SoneTextParser}.
  51  *
  52  * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
  53  */
  54 public class ParserFilter implements Filter {
  55
  56         /** The core. */
  57         private final Core core;
  58
  59         /** The link parser. */
  60         private final SoneTextParser soneTextParser;
  61
  62         /** The template context factory. */
  63         private final TemplateContextFactory templateContextFactory;
  64
  65         /** The template for {@link PlainTextPart}s. */
  66         private static final Template plainTextTemplate = TemplateParser.parse(new StringReader("<%text|html>"));
  67
  68         /** The template for {@link FreenetLinkPart}s. */
  69         private static final Template linkTemplate = TemplateParser.parse(new StringReader("<a class=\"<%cssClass|html>\" href=\"<%link|html>\" title=\"<%title|html>\"><%text|html></a>"));
  70
  71         /**
  72          * Creates a new filter that runs its input through a {@link SoneTextParser}
  73          * .
  74          *
  75          * @param core
  76          *            The core
  77          * @param templateContextFactory
  78          *            The context factory for rendering the parts
  79          * @param soneTextParser
  80          *            The Sone text parser
  81          */
  82         public ParserFilter(Core core, TemplateContextFactory templateContextFactory, SoneTextParser soneTextParser) {
  83                 this.core = core;
  84                 this.templateContextFactory = templateContextFactory;
  85                 this.soneTextParser = soneTextParser;
  86         }
  87
  88         /**
  89          * {@inheritDoc}
  90          */
  91         @Override
  92         public Object format(TemplateContext templateContext, Object data, Map<String, Object> parameters) {
  93                 String text = valueOf(data);
  94                 int length = parseInt(valueOf(parameters.get("length")), -1);
  95                 int cutOffLength = parseInt(valueOf(parameters.get("cut-off-length")), length);
  96                 Object sone = parameters.get("sone");
  97                 if (sone instanceof String) {
  98                         sone = core.getSone((String) sone).orNull();
  99                 }
 100                 FreenetRequest request = (FreenetRequest) templateContext.get("request");
 101                 SoneTextParserContext context = new SoneTextParserContext(request, (Sone) sone);
 102                 StringWriter parsedTextWriter = new StringWriter();
 103                 Iterable<Part> parts = soneTextParser.parse(text, context);
 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 = 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 += 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                 return parsedTextWriter.toString();
 135         }
 136
 137         //
 138         // PRIVATE METHODS
 139         //
 140
 141         /**
 142          * Renders the given parts.
 143          *
 144          * @param writer
 145          *            The writer to render the parts to
 146          * @param parts
 147          *            The parts to render
 148          */
 149         private void render(Writer writer, Iterable<Part> parts) {
 150                 for (Part part : parts) {
 151                         render(writer, part);
 152                 }
 153         }
 154
 155         /**
 156          * Renders the given part.
 157          *
 158          * @param writer
 159          *            The writer to render the part to
 160          * @param part
 161          *            The part to render
 162          */
 163         @SuppressWarnings("unchecked")
 164         private void render(Writer writer, Part part) {
 165                 if (part instanceof PlainTextPart) {
 166                         render(writer, (PlainTextPart) part);
 167                 } else if (part instanceof FreenetLinkPart) {
 168                         render(writer, (FreenetLinkPart) part);
 169                 } else if (part instanceof LinkPart) {
 170                         render(writer, (LinkPart) part);
 171                 } else if (part instanceof SonePart) {
 172                         render(writer, (SonePart) part);
 173                 } else if (part instanceof PostPart) {
 174                         render(writer, (PostPart) part);
 175                 } else if (part instanceof Iterable<?>) {
 176                         render(writer, (Iterable<Part>) part);
 177                 }
 178         }
 179
 180         /**
 181          * Renders the given plain-text part.
 182          *
 183          * @param writer
 184          *            The writer to render the part to
 185          * @param plainTextPart
 186          *            The part to render
 187          */
 188         private void render(Writer writer, PlainTextPart plainTextPart) {
 189                 TemplateContext templateContext = templateContextFactory.createTemplateContext();
 190                 templateContext.set("text", plainTextPart.getText());
 191                 plainTextTemplate.render(templateContext, writer);
 192         }
 193
 194         /**
 195          * Renders the given freenet link part.
 196          *
 197          * @param writer
 198          *            The writer to render the part to
 199          * @param freenetLinkPart
 200          *            The part to render
 201          */
 202         private void render(Writer writer, FreenetLinkPart freenetLinkPart) {
 203                 renderLink(writer, "/" + freenetLinkPart.getLink(), freenetLinkPart.getText(), freenetLinkPart.getTitle(), freenetLinkPart.isTrusted() ? "freenet-trusted" : "freenet");
 204         }
 205
 206         /**
 207          * Renders the given link part.
 208          *
 209          * @param writer
 210          *            The writer to render the part to
 211          * @param linkPart
 212          *            The part to render
 213          */
 214         private void render(Writer writer, LinkPart linkPart) {
 215                 try {
 216                         renderLink(writer, "/external-link/?_CHECKED_HTTP_=" + URLEncoder.encode(linkPart.getLink(), "UTF-8"), linkPart.getText(), linkPart.getTitle(), "internet");
 217                 } catch (UnsupportedEncodingException uee1) {
 218                         /* not possible for UTF-8. */
 219                         throw new RuntimeException("The JVM does not support UTF-8 encoding!", uee1);
 220                 }
 221         }
 222
 223         /**
 224          * Renders the given Sone part.
 225          *
 226          * @param writer
 227          *            The writer to render the part to
 228          * @param sonePart
 229          *            The part to render
 230          */
 231         private void render(Writer writer, SonePart sonePart) {
 232                 if ((sonePart.getSone() != null) && (sonePart.getSone().getName() != null)) {
 233                         renderLink(writer, "viewSone.html?sone=" + sonePart.getSone().getId(), SoneAccessor.getNiceName(sonePart.getSone()), SoneAccessor.getNiceName(sonePart.getSone()), "in-sone");
 234                 } else {
 235                         renderLink(writer, "/WebOfTrust/ShowIdentity?id=" + sonePart.getSone().getId(), sonePart.getSone().getId(), sonePart.getSone().getId(), "in-sone");
 236                 }
 237         }
 238
 239         /**
 240          * Renders the given post part.
 241          *
 242          * @param writer
 243          *            The writer to render the part to
 244          * @param postPart
 245          *            The part to render
 246          */
 247         private void render(Writer writer, PostPart postPart) {
 248                 SoneTextParser parser = new SoneTextParser(core, core);
 249                 SoneTextParserContext parserContext = new SoneTextParserContext(null, postPart.getPost().getSone());
 250                 Iterable<Part> parts = parser.parse(postPart.getPost().getText(), parserContext);
 251                 StringBuilder excerpt = new StringBuilder();
 252                 for (Part part : parts) {
 253                         excerpt.append(part.getText());
 254                         if (excerpt.length() > 20) {
 255                                 int lastSpace = excerpt.lastIndexOf(" ", 20);
 256                                 if (lastSpace > -1) {
 257                                         excerpt.setLength(lastSpace);
 258                                 } else {
 259                                         excerpt.setLength(20);
 260                                 }
 261                                 excerpt.append("…");
 262                                 break;
 263                         }
 264                 }
 265                 renderLink(writer, "viewPost.html?post=" + postPart.getPost().getId(), excerpt.toString(), SoneAccessor.getNiceName(postPart.getPost().getSone()), "in-sone");
 266         }
 267
 268         /**
 269          * Renders the given link.
 270          *
 271          * @param writer
 272          *            The writer to render the link to
 273          * @param link
 274          *            The link to render
 275          * @param text
 276          *            The text of the link
 277          * @param title
 278          *            The title of the link
 279          * @param cssClass
 280          *            The CSS class of the link
 281          */
 282         private void renderLink(Writer writer, String link, String text, String title, String cssClass) {
 283                 TemplateContext templateContext = templateContextFactory.createTemplateContext();
 284                 templateContext.set("cssClass", cssClass);
 285                 templateContext.set("link", link);
 286                 templateContext.set("text", text);
 287                 templateContext.set("title", title);
 288                 linkTemplate.render(templateContext, writer);
 289         }
 290
 291 }