Pages

Signed-off-by: Minecon724 <git@m724.eu>

.gitignore

@@ -37,5 +37,5 @@ build/
 ### Mac OS ###
 .DS_Store
 
-/example_blog/
+/example-blog/
 /m724/

.gitmodules

@@ -1,3 +0,0 @@
-[submodule "example-blog"]
-	path = example-blog
-	url = git@git.m724.eu:Minecon724/example-blog.git

.idea/vcs.xml

@@ -2,7 +2,7 @@
 <project version="4">
   <component name="VcsDirectoryMappings">
     <mapping directory="$PROJECT_DIR$" vcs="Git" />
-    <mapping directory="$PROJECT_DIR$/example_blog" vcs="Git" />
+    <mapping directory="$PROJECT_DIR$/example-blog" vcs="Git" />
     <mapping directory="$PROJECT_DIR$/m724" vcs="Git" />
   </component>
 </project>

src/main/java/eu/m724/blog/BlogBuilder.java

@@ -10,10 +10,7 @@ import eu.m724.blog.compress.CommonsCompressor;
 import eu.m724.blog.compress.CompressException;
 import eu.m724.blog.compress.FileCompressor;
 import eu.m724.blog.compress.NoSuchAlgorithmException;
-import eu.m724.blog.object.Article;
-import eu.m724.blog.object.Feed;
-import eu.m724.blog.object.RenderOptions;
-import eu.m724.blog.object.Site;
+import eu.m724.blog.object.*;
 import eu.m724.blog.server.Server;
 import eu.m724.blog.template.TemplateRenderer;
 import eu.m724.blog.vc.GitVersionControl;
@@ -153,7 +150,9 @@ public class BlogBuilder {
 
         LOGGER.debug("Rendering meta...");
         articles.sort(Comparator.comparing(Article::createdAt).reversed());
-        Files.writeString(outputDirectory.resolve("index.html"), template.renderIndex(articles));
+
+        LOGGER.debug("Rendering pages...");
+        renderIndexPages(articles);
 
         Files.writeString(outputDirectory.resolve("articles.rss"), Feed.generateRss(site, articles));
 
@@ -173,6 +172,25 @@ public class BlogBuilder {
         }
     }
 
+    private void renderIndexPages(List<Article> articles) throws IOException {
+        int lastPage = Math.max(Math.ceilDiv(articles.size(), site.articlesPerPage()), 1);
+        Files.writeString(outputDirectory.resolve("index.html"), template.renderIndexPage(PageNumbers.create(1, lastPage), articles.subList(0, site.articlesPerPage())));
+
+        var pageDirectory = outputDirectory.resolve("page");
+        Files.createDirectory(pageDirectory);
+
+        // yes we do render page 1 twice, because https://git.m724.eu/Minecon724/blog-software-java/issues/8
+        for (int page=1; page<=lastPage; page++) {
+            var startIndex = (page - 1) * site.articlesPerPage();
+            var endIndex = Math.min(startIndex + site.articlesPerPage(), articles.size());
+            var pageArticles = articles.subList(startIndex, endIndex);
+
+            var renderedPage = template.renderIndexPage(PageNumbers.create(page, lastPage), pageArticles);
+
+            Files.writeString(pageDirectory.resolve(page + ".html"), renderedPage);
+        }
+    }
+
     private List<Article> renderArticles() throws IOException {
         Files.createDirectory(outputDirectory.resolve("article"));
         var articleDirectory = workingDirectory.resolve("articles");

src/main/java/eu/m724/blog/object/PageNumbers.java

@@ -0,0 +1,38 @@
+/*
+ * Copyright (c) 2025  blog-software-java developers
+ * blog-software-java is licensed under the GNU General Public License. See the LICENSE.md file
+ * in the project root for the full license text.
+ */
+
+package eu.m724.blog.object;
+
+/**
+ * PageNumbers simplifies tracking page numbers
+ * @param current current page number (1 is first)
+ * @param last last page number (equals number of pages)
+ * @param previous previous page number (>=1)
+ * @param next next page number (<=last)
+ * @param isFirstPage is current page the first page (=1)
+ * @param isLastPage is current page the last page (=last)
+ */
+public record PageNumbers(
+        int current,
+        int last,
+
+        int previous,
+        int next,
+
+        boolean isFirstPage,
+        boolean isLastPage
+) {
+    // after upgrade to java 22+ this could be a constructor
+    public static PageNumbers create(int current, int last) {
+        var previous = Math.max(current - 1, 1);
+        var next = Math.min(current + 1, last);
+
+        var isFirstPage = current == 1;
+        var isLastPage = current == last;
+
+        return new PageNumbers(current, last, previous, next, isFirstPage, isLastPage);
+    }
+}

src/main/java/eu/m724/blog/object/Site.java

@@ -27,6 +27,8 @@ public record Site(
 
         String directory,
 
+        int articlesPerPage,
+
         boolean templateArticles,
 
         Map<String, Object> custom
@@ -35,6 +37,7 @@ public record Site(
             "Misconfigured blog",
             "/",
             "/",
+            10,
             false,
             Map.of()
     );
@@ -52,6 +55,7 @@ public record Site(
 
         String name = (String) yaml.getOrDefault("name", DEFAULT.name());
         String baseUrl = (String) yaml.getOrDefault("baseUrl", DEFAULT.baseUrl());
+        var articlesPerPage = (int) yaml.getOrDefault("articlesPerPage", DEFAULT.articlesPerPage());
         var templateArticles = (boolean) yaml.getOrDefault("templateArticles", DEFAULT.templateArticles());
 
         String directory = DEFAULT.directory();
@@ -64,7 +68,7 @@ public record Site(
         }
 
         return new Site(
-                name, baseUrl, directory, templateArticles, yaml
+                name, baseUrl, directory, articlesPerPage, templateArticles, yaml
         );
     }
 }

src/main/java/eu/m724/blog/template/TemplateRenderer.java

@@ -8,6 +8,7 @@ package eu.m724.blog.template;
 
 import eu.m724.blog.Minifier;
 import eu.m724.blog.object.Article;
+import eu.m724.blog.object.PageNumbers;
 import eu.m724.blog.object.Site;
 import io.pebbletemplates.pebble.PebbleEngine;
 import io.pebbletemplates.pebble.loader.FileLoader;
@@ -58,12 +59,14 @@ public class TemplateRenderer {
     /**
      * Renders the index page using this template.
      *
-     * @param articles the {@link Article}s to be included in the index page
+     * @param articles the {@link Article}s to be included in the <strong>CURRENT</strong> page
+     * @param pageNumbers a {@link PageNumbers} instance for the current page
      * @return the rendered index HTML page as a string
      * @throws IOException if an error occurs during the template evaluation
      */
-    public String renderIndex(List<Article> articles) throws IOException {
+    public String renderIndexPage(PageNumbers pageNumbers, List<Article> articles) throws IOException {
         var context = Map.of(
+                "page", pageNumbers,
                 "articles", articles
         );