2 * Sone - ImageLinkFilter.java - Copyright © 2011–2013 David Roden
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.
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.
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/>.
18 package net.pterodactylus.sone.template;
20 import java.io.StringReader;
21 import java.io.StringWriter;
24 import net.pterodactylus.sone.core.Core;
25 import net.pterodactylus.sone.data.Image;
26 import net.pterodactylus.util.number.Numbers;
27 import net.pterodactylus.util.template.Filter;
28 import net.pterodactylus.util.template.Template;
29 import net.pterodactylus.util.template.TemplateContext;
30 import net.pterodactylus.util.template.TemplateContextFactory;
31 import net.pterodactylus.util.template.TemplateParser;
33 import com.google.common.base.Optional;
36 * Template filter that turns an {@link Image} into an HTML <img> tag,
37 * using some parameters to influence parameters of the image.
39 * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
41 public class ImageLinkFilter implements Filter {
43 /** The template to render for the <img> tag. */
44 private static final Template linkTemplate = TemplateParser.parse(new StringReader("<img<%ifnull !class> class=\"<%class|css>\"<%/if> src=\"<%src|html><%if forceDownload>?forcedownload=true<%/if>\" alt=\"<%alt|html>\" title=\"<%title|html>\" width=\"<%width|html>\" height=\"<%height|html>\" style=\"position: relative;<%ifnull ! top>top: <% top|html>;<%/if><%ifnull ! left>left: <% left|html>;<%/if>\"/>"));
47 private final Core core;
49 /** The template context factory. */
50 private final TemplateContextFactory templateContextFactory;
53 * Creates a new image link filter.
57 * @param templateContextFactory
58 * The template context factory
60 public ImageLinkFilter(Core core, TemplateContextFactory templateContextFactory) {
62 this.templateContextFactory = templateContextFactory;
66 public Object format(TemplateContext templateContext, Object data, Map<String, Object> parameters) {
68 if (data instanceof String) {
69 image = core.getImage((String) data).orNull();
70 } else if (data instanceof Image) {
76 String imageClass = getParameterAsString(parameters, "class");
77 int maxWidth = Numbers.safeParseInteger(parameters.get("max-width"), Integer.MAX_VALUE);
78 int maxHeight = Numbers.safeParseInteger(parameters.get("max-height"), Integer.MAX_VALUE);
79 String mode = getParameterAsString(parameters, "mode");
80 String title = getParameterAsString(parameters, "title");
82 TemplateContext linkTemplateContext = templateContextFactory.createTemplateContext();
83 linkTemplateContext.set("class", imageClass);
84 if (image.isInserted()) {
85 linkTemplateContext.set("src", "/" + image.getKey());
86 linkTemplateContext.set("forceDownload", true);
88 linkTemplateContext.set("src", "getImage.html?image=" + image.getId());
90 int imageWidth = image.getWidth();
91 int imageHeight = image.getHeight();
92 if ("enlarge".equals(mode)) {
93 double scale = Math.max(maxWidth / (double) imageWidth, maxHeight / (double) imageHeight);
94 linkTemplateContext.set("width", (int) (imageWidth * scale + 0.5));
95 linkTemplateContext.set("height", (int) (imageHeight * scale + 0.5));
96 linkTemplateContext.set("left", String.format("%dpx", (int) (maxWidth - (imageWidth * scale)) / 2));
97 linkTemplateContext.set("top", String.format("%dpx", (int) (maxHeight - (imageHeight * scale)) / 2));
100 if ((imageWidth > maxWidth) || (imageHeight > maxHeight)) {
101 scale = Math.min(maxWidth / (double) imageWidth, maxHeight / (double) imageHeight);
103 linkTemplateContext.set("width", (int) (imageWidth * scale + 0.5));
104 linkTemplateContext.set("height", (int) (imageHeight * scale + 0.5));
106 linkTemplateContext.set("alt", Optional.fromNullable(title).or(image.getDescription()));
107 linkTemplateContext.set("title", Optional.fromNullable(title).or(image.getTitle()));
109 StringWriter stringWriter = new StringWriter();
110 linkTemplate.render(linkTemplateContext, stringWriter);
111 return stringWriter.toString();
114 private static String getParameterAsString(Map<String, Object> parameters, String key) {
115 Object parameter = parameters.get(key);
116 return (parameter == null) ? null : String.valueOf(parameter);