2 * Sone - ImageLinkFilter.java - Copyright © 2011–2019 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 static java.lang.Integer.MAX_VALUE;
21 import static java.lang.String.valueOf;
22 import static net.pterodactylus.sone.utils.NumberParsers.parseInt;
24 import java.io.StringReader;
25 import java.io.StringWriter;
28 import net.pterodactylus.sone.core.Core;
29 import net.pterodactylus.sone.data.Image;
30 import net.pterodactylus.util.template.Filter;
31 import net.pterodactylus.util.template.HtmlFilter;
32 import net.pterodactylus.util.template.Template;
33 import net.pterodactylus.util.template.TemplateContext;
34 import net.pterodactylus.util.template.TemplateContextFactory;
35 import net.pterodactylus.util.template.TemplateParser;
37 import com.google.common.base.Function;
38 import com.google.common.base.Optional;
41 * Template filter that turns an {@link Image} into an HTML <img> tag,
42 * using some parameters to influence parameters of the image.
44 public class ImageLinkFilter implements Filter {
46 /** The template to render for the <img> tag. */
47 private static final Template linkTemplate = TemplateParser.parse(new StringReader("<img<%ifnull !class> class=\"<%class|css>\"<%/if> src=\"<%src|html>\" 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>\"/>"));
50 private final Core core;
52 /** The template context factory. */
53 private final TemplateContextFactory templateContextFactory = new TemplateContextFactory();
55 public ImageLinkFilter(Core core) {
57 templateContextFactory.addFilter("html", new HtmlFilter());
58 templateContextFactory.addFilter("css", new CssClassNameFilter());
65 public Object format(TemplateContext templateContext, Object data, Map<String, Object> parameters) {
67 if (data instanceof String) {
68 image = core.getImage((String) data, false);
69 } else if (data instanceof Image) {
75 String imageClass = Optional.fromNullable(parameters.get("class")).transform(getStringValue()).orNull();
76 int maxWidth = parseInt(valueOf(parameters.get("max-width")), MAX_VALUE);
77 int maxHeight = parseInt(valueOf(parameters.get("max-height")), MAX_VALUE);
78 String mode = valueOf(parameters.get("mode"));
79 String title = Optional.fromNullable(parameters.get("title")).transform(getStringValue()).orNull();
81 TemplateContext linkTemplateContext = templateContextFactory.createTemplateContext();
82 linkTemplateContext.set("class", imageClass);
83 if (image.isInserted()) {
84 linkTemplateContext.set("src", "/" + image.getKey());
86 linkTemplateContext.set("src", "getImage.html?image=" + image.getId());
88 int imageWidth = image.getWidth();
89 int imageHeight = image.getHeight();
90 if ("enlarge".equals(mode)) {
91 double scale = Math.max(maxWidth / (double) imageWidth, maxHeight / (double) imageHeight);
92 linkTemplateContext.set("width", (int) (imageWidth * scale + 0.5));
93 linkTemplateContext.set("height", (int) (imageHeight * scale + 0.5));
94 linkTemplateContext.set("left", String.format("%dpx", (int) (maxWidth - (imageWidth * scale)) / 2));
95 linkTemplateContext.set("top", String.format("%dpx", (int) (maxHeight - (imageHeight * scale)) / 2));
98 if ((imageWidth > maxWidth) || (imageHeight > maxHeight)) {
99 scale = Math.min(maxWidth / (double) imageWidth, maxHeight / (double) imageHeight);
101 linkTemplateContext.set("width", (int) (imageWidth * scale + 0.5));
102 linkTemplateContext.set("height", (int) (imageHeight * scale + 0.5));
104 linkTemplateContext.set("alt", Optional.fromNullable(title).or(image.getDescription()));
105 linkTemplateContext.set("title", Optional.fromNullable(title).or(image.getTitle()));
107 StringWriter stringWriter = new StringWriter();
108 linkTemplate.render(linkTemplateContext, stringWriter);
109 return stringWriter.toString();
112 private Function<Object, String> getStringValue() {
113 return new Function<Object, String>() {
115 public String apply(Object input) {
116 return (input != null) ? input.toString() : null;