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

   1 package net.pterodactylus.sone.template;
   2
   3 import static java.lang.String.valueOf;
   4 import static net.pterodactylus.sone.utils.NumberParsers.parseInt;
   5
   6 import java.io.IOException;
   7 import java.io.StringReader;
   8 import java.io.StringWriter;
   9 import java.io.UnsupportedEncodingException;
  10 import java.io.Writer;
  11 import java.net.URLEncoder;
  12 import java.util.ArrayList;
  13 import java.util.List;
  14 import java.util.Map;
  15
  16 import net.pterodactylus.sone.core.Core;
  17 import net.pterodactylus.sone.data.Album;
  18 import net.pterodactylus.sone.data.Sone;
  19 import net.pterodactylus.sone.text.AlbumPart;
  20 import net.pterodactylus.sone.text.FreenetLinkPart;
  21 import net.pterodactylus.sone.text.LinkPart;
  22 import net.pterodactylus.sone.text.Part;
  23 import net.pterodactylus.sone.text.PartContainer;
  24 import net.pterodactylus.sone.text.PlainTextPart;
  25 import net.pterodactylus.sone.text.PostPart;
  26 import net.pterodactylus.sone.text.SonePart;
  27 import net.pterodactylus.sone.text.SoneTextParser;
  28 import net.pterodactylus.sone.text.SoneTextParserContext;
  29 import net.pterodactylus.util.template.Filter;
  30 import net.pterodactylus.util.template.Template;
  31 import net.pterodactylus.util.template.TemplateContext;
  32 import net.pterodactylus.util.template.TemplateContextFactory;
  33 import net.pterodactylus.util.template.TemplateParser;
  34
  35 /**
  36  * {@link Filter} implementation that renders an {@link Iterable} (such as a {@link PartContainer}) of {@link Part}s to HTML.
  37  *
  38  * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
  39  */
  40 public class RenderFilter implements Filter {
  41
  42         private static final Template plainTextTemplate = TemplateParser.parse(new StringReader("<%text|html>"));
  43         private static final Template linkTemplate =
  44                         TemplateParser.parse(new StringReader("<a class=\"<%cssClass|html>\" href=\"<%link|html>\" title=\"<%title|html>\"><%text|html></a>"));
  45         private final Core core;
  46         private final TemplateContextFactory templateContextFactory;
  47
  48         public RenderFilter(Core core, TemplateContextFactory templateContextFactory) {
  49                 this.core = core;
  50                 this.templateContextFactory = templateContextFactory;
  51         }
  52
  53         @Override
  54         public Object format(TemplateContext templateContext, Object data, Map<String, Object> parameters) {
  55                 if (!(data instanceof Iterable<?>)) {
  56                         return null;
  57                 }
  58                 Iterable<Part> parts = (Iterable<Part>) data;
  59                 int length = parseInt(valueOf(parameters.get("length")), -1);
  60                 int cutOffLength = parseInt(valueOf(parameters.get("cut-off-length")), length);
  61                 StringWriter parsedTextWriter = new StringWriter();
  62                 if (length > -1) {
  63                         int allPartsLength = 0;
  64                         List<Part> shortenedParts = new ArrayList<Part>();
  65                         for (Part part : parts) {
  66                                 if (part instanceof PlainTextPart) {
  67                                         String longText = part.getText();
  68                                         if (allPartsLength < cutOffLength) {
  69                                                 if ((allPartsLength + longText.length()) > cutOffLength) {
  70                                                         shortenedParts.add(new PlainTextPart(longText.substring(0, cutOffLength - allPartsLength) + "…"));
  71                                                 } else {
  72                                                         shortenedParts.add(part);
  73                                                 }
  74                                         }
  75                                         allPartsLength += longText.length();
  76                                 } else if (part instanceof LinkPart) {
  77                                         if (allPartsLength < cutOffLength) {
  78                                                 shortenedParts.add(part);
  79                                         }
  80                                         allPartsLength += part.getText().length();
  81                                 } else {
  82                                         if (allPartsLength < cutOffLength) {
  83                                                 shortenedParts.add(part);
  84                                         }
  85                                 }
  86                         }
  87                         if (allPartsLength >= length) {
  88                                 parts = shortenedParts;
  89                         }
  90                 }
  91                 render(parsedTextWriter, parts);
  92                 return parsedTextWriter.toString();
  93         }
  94
  95         private void render(Writer writer, Iterable<Part> parts) {
  96                 for (Part part : parts) {
  97                         render(writer, part);
  98                 }
  99         }
 100
 101         private void render(Writer writer, Part part) {
 102                 if (part instanceof PlainTextPart) {
 103                         render(writer, (PlainTextPart) part);
 104                 } else if (part instanceof FreenetLinkPart) {
 105                         render(writer, (FreenetLinkPart) part);
 106                 } else if (part instanceof LinkPart) {
 107                         render(writer, (LinkPart) part);
 108                 } else if (part instanceof SonePart) {
 109                         render(writer, (SonePart) part);
 110                 } else if (part instanceof PostPart) {
 111                         render(writer, (PostPart) part);
 112                 } else if (part instanceof AlbumPart) {
 113                         render(writer, (AlbumPart) part);
 114                 } else if (part instanceof Iterable<?>) {
 115                         render(writer, (Iterable<Part>) part);
 116                 }
 117         }
 118
 119         private void render(Writer writer, PlainTextPart plainTextPart) {
 120                 TemplateContext templateContext = templateContextFactory.createTemplateContext();
 121                 templateContext.set("text", plainTextPart.getText());
 122                 plainTextTemplate.render(templateContext, writer);
 123         }
 124
 125         private void render(Writer writer, FreenetLinkPart freenetLinkPart) {
 126                 renderLink(writer, "/" + freenetLinkPart.getLink(), freenetLinkPart.getText(), freenetLinkPart.getTitle(),
 127                                 freenetLinkPart.isTrusted() ? "freenet-trusted" : "freenet");
 128         }
 129
 130         private void render(Writer writer, LinkPart linkPart) {
 131                 try {
 132                         renderLink(writer, "/external-link/?_CHECKED_HTTP_=" + URLEncoder.encode(linkPart.getLink(), "UTF-8"), linkPart.getText(),
 133                                         linkPart.getTitle(), "internet");
 134                 } catch (UnsupportedEncodingException uee1) {
 135                         /* not possible for UTF-8. */
 136                         throw new RuntimeException("The JVM does not support UTF-8 encoding!", uee1);
 137                 }
 138         }
 139
 140         private void render(Writer writer, SonePart sonePart) {
 141                 Sone sone = sonePart.getSone();
 142                 if ((sone != null) && (sone.getName() != null)) {
 143                         String niceName = SoneAccessor.getNiceName(sone);
 144                         renderLink(writer, "viewSone.html?sone=" + sone.getId(), niceName, niceName, "in-sone");
 145                 } else {
 146                         renderLink(writer, "/WebOfTrust/ShowIdentity?id=" + sone.getId(), sone.getId(), sone.getId(), "in-sone");
 147                 }
 148         }
 149
 150         private void render(Writer writer, PostPart postPart) {
 151                 SoneTextParser parser = new SoneTextParser(core, core, core);
 152                 SoneTextParserContext parserContext = new SoneTextParserContext(null, postPart.getPost().getSone());
 153                 try {
 154                         Iterable<Part> parts = parser.parse(parserContext, new StringReader(postPart.getPost().getText()));
 155                         StringBuilder excerpt = new StringBuilder();
 156                         for (Part part : parts) {
 157                                 excerpt.append(part.getText());
 158                                 if (excerpt.length() > 20) {
 159                                         int lastSpace = excerpt.lastIndexOf(" ", 20);
 160                                         if (lastSpace > -1) {
 161                                                 excerpt.setLength(lastSpace);
 162                                         } else {
 163                                                 excerpt.setLength(20);
 164                                         }
 165                                         excerpt.append("…");
 166                                         break;
 167                                 }
 168                         }
 169                         renderLink(writer, "viewPost.html?post=" + postPart.getPost().getId(), excerpt.toString(),
 170                                         SoneAccessor.getNiceName(postPart.getPost().getSone()), postPart.usesDeprecatedLink() ? "internet" : "in-sone");
 171                 } catch (IOException ioe1) {
 172                         /* StringReader shouldn’t throw. */
 173                 }
 174         }
 175
 176         private void render(Writer writer, AlbumPart albumPart) {
 177                 Album album = albumPart.getAlbum();
 178                 renderLink(writer, String.format("imageBrowser.html?album=%s", album.getId()), album.getTitle(), album.getDescription(), "in-sone");
 179         }
 180
 181         private void renderLink(Writer writer, String link, String text, String title, String cssClass) {
 182                 TemplateContext templateContext = templateContextFactory.createTemplateContext();
 183                 templateContext.set("cssClass", cssClass);
 184                 templateContext.set("link", link);
 185                 templateContext.set("text", text);
 186                 templateContext.set("title", title);
 187                 linkTemplate.render(templateContext, writer);
 188         }
 189
 190 }