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.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 = valueOf(data);
  93                 int length = parseInt(valueOf(parameters.get("length")), -1);
  94                 int cutOffLength = parseInt(valueOf(parameters.get("cut-off-length")), length);
  95                 Object sone = parameters.get("sone");
  96                 if (sone instanceof String) {
  97                         sone = core.getSone((String) sone).orNull();
  98                 }
  99                 SoneTextParserContext context = new SoneTextParserContext((Sone) sone);
 100                 StringWriter parsedTextWriter = new StringWriter();
 101                 Iterable<Part> parts = soneTextParser.parse(text, context);
 102                 if (length > -1) {
 103                         int allPartsLength = 0;
 104                         List<Part> shortenedParts = new ArrayList<Part>();
 105                         for (Part part : parts) {
 106                                 if (part instanceof PlainTextPart) {
 107                                         String longText = part.getText();
 108                                         if (allPartsLength < cutOffLength) {
 109                                                 if ((allPartsLength + longText.length()) > cutOffLength) {
 110                                                         shortenedParts.add(new PlainTextPart(longText.substring(0, cutOffLength - allPartsLength) + "…"));
 111                                                 } else {
 112                                                         shortenedParts.add(part);
 113                                                 }
 114                                         }
 115                                         allPartsLength += longText.length();
 116                                 } else if (part instanceof LinkPart) {
 117                                         if (allPartsLength < cutOffLength) {
 118                                                 shortenedParts.add(part);
 119                                         }
 120                                         allPartsLength += part.getText().length();
 121                                 } else {
 122                                         if (allPartsLength < cutOffLength) {
 123                                                 shortenedParts.add(part);
 124                                         }
 125                                 }
 126                         }
 127                         if (allPartsLength >= length) {
 128                                 parts = shortenedParts;
 129                         }
 130                 }
 131                 render(parsedTextWriter, parts);
 132                 return parsedTextWriter.toString();
 133         }
 134
 135         //
 136         // PRIVATE METHODS
 137         //
 138
 139         /**
 140          * Renders the given parts.
 141          *
 142          * @param writer
 143          *            The writer to render the parts to
 144          * @param parts
 145          *            The parts to render
 146          */
 147         private void render(Writer writer, Iterable<Part> parts) {
 148                 for (Part part : parts) {
 149                         render(writer, part);
 150                 }
 151         }
 152
 153         /**
 154          * Renders the given part.
 155          *
 156          * @param writer
 157          *            The writer to render the part to
 158          * @param part
 159          *            The part to render
 160          */
 161         @SuppressWarnings("unchecked")
 162         private void render(Writer writer, Part part) {
 163                 if (part instanceof PlainTextPart) {
 164                         render(writer, (PlainTextPart) part);
 165                 } else if (part instanceof FreenetLinkPart) {
 166                         render(writer, (FreenetLinkPart) part);
 167                 } else if (part instanceof LinkPart) {
 168                         render(writer, (LinkPart) part);
 169                 } else if (part instanceof SonePart) {
 170                         render(writer, (SonePart) part);
 171                 } else if (part instanceof PostPart) {
 172                         render(writer, (PostPart) part);
 173                 } else if (part instanceof Iterable<?>) {
 174                         render(writer, (Iterable<Part>) part);
 175                 }
 176         }
 177
 178         /**
 179          * Renders the given plain-text part.
 180          *
 181          * @param writer
 182          *            The writer to render the part to
 183          * @param plainTextPart
 184          *            The part to render
 185          */
 186         private void render(Writer writer, PlainTextPart plainTextPart) {
 187                 TemplateContext templateContext = templateContextFactory.createTemplateContext();
 188                 templateContext.set("text", plainTextPart.getText());
 189                 plainTextTemplate.render(templateContext, writer);
 190         }
 191
 192         /**
 193          * Renders the given freenet link part.
 194          *
 195          * @param writer
 196          *            The writer to render the part to
 197          * @param freenetLinkPart
 198          *            The part to render
 199          */
 200         private void render(Writer writer, FreenetLinkPart freenetLinkPart) {
 201                 renderLink(writer, "/" + freenetLinkPart.getLink(), freenetLinkPart.getText(), freenetLinkPart.getTitle(), freenetLinkPart.isTrusted() ? "freenet-trusted" : "freenet");
 202         }
 203
 204         /**
 205          * Renders the given link part.
 206          *
 207          * @param writer
 208          *            The writer to render the part to
 209          * @param linkPart
 210          *            The part to render
 211          */
 212         private void render(Writer writer, LinkPart linkPart) {
 213                 try {
 214                         renderLink(writer, "/external-link/?_CHECKED_HTTP_=" + URLEncoder.encode(linkPart.getLink(), "UTF-8"), linkPart.getText(), linkPart.getTitle(), "internet");
 215                 } catch (UnsupportedEncodingException uee1) {
 216                         /* not possible for UTF-8. */
 217                         throw new RuntimeException("The JVM does not support UTF-8 encoding!", uee1);
 218                 }
 219         }
 220
 221         /**
 222          * Renders the given Sone part.
 223          *
 224          * @param writer
 225          *            The writer to render the part to
 226          * @param sonePart
 227          *            The part to render
 228          */
 229         private void render(Writer writer, SonePart sonePart) {
 230                 if ((sonePart.getSone() != null) && (sonePart.getSone().getName() != null)) {
 231                         renderLink(writer, "viewSone.html?sone=" + sonePart.getSone().getId(), SoneAccessor.getNiceName(sonePart.getSone()), SoneAccessor.getNiceName(sonePart.getSone()), "in-sone");
 232                 } else {
 233                         renderLink(writer, "/WebOfTrust/ShowIdentity?id=" + sonePart.getSone().getId(), sonePart.getSone().getId(), sonePart.getSone().getId(), "in-sone");
 234                 }
 235         }
 236
 237         /**
 238          * Renders the given post part.
 239          *
 240          * @param writer
 241          *            The writer to render the part to
 242          * @param postPart
 243          *            The part to render
 244          */
 245         private void render(Writer writer, PostPart postPart) {
 246                 SoneTextParser parser = new SoneTextParser(core, core);
 247                 SoneTextParserContext parserContext = new SoneTextParserContext(postPart.getPost().getSone());
 248                 Iterable<Part> parts = parser.parse(postPart.getPost().getText(), parserContext);
 249                 StringBuilder excerpt = new StringBuilder();
 250                 for (Part part : parts) {
 251                         excerpt.append(part.getText());
 252                         if (excerpt.length() > 20) {
 253                                 int lastSpace = excerpt.lastIndexOf(" ", 20);
 254                                 if (lastSpace > -1) {
 255                                         excerpt.setLength(lastSpace);
 256                                 } else {
 257                                         excerpt.setLength(20);
 258                                 }
 259                                 excerpt.append("…");
 260                                 break;
 261                         }
 262                 }
 263                 renderLink(writer, "viewPost.html?post=" + postPart.getPost().getId(), excerpt.toString(), SoneAccessor.getNiceName(postPart.getPost().getSone()), "in-sone");
 264         }
 265
 266         /**
 267          * Renders the given link.
 268          *
 269          * @param writer
 270          *            The writer to render the link to
 271          * @param link
 272          *            The link to render
 273          * @param text
 274          *            The text of the link
 275          * @param title
 276          *            The title of the link
 277          * @param cssClass
 278          *            The CSS class of the link
 279          */
 280         private void renderLink(Writer writer, String link, String text, String title, String cssClass) {
 281                 TemplateContext templateContext = templateContextFactory.createTemplateContext();
 282                 templateContext.set("cssClass", cssClass);
 283                 templateContext.set("link", link);
 284                 templateContext.set("text", text);
 285                 templateContext.set("title", title);
 286                 linkTemplate.render(templateContext, writer);
 287         }
 288
 289 }