Page templates

Closes #8

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

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

@@ -152,7 +152,7 @@ public class BlogBuilder {
         articles.sort(Comparator.comparing(Article::createdAt).reversed());
 
         LOGGER.debug("Rendering pages...");
-        renderIndexPages(articles);
+        renderIndexAndPages(articles);
 
         Files.writeString(outputDirectory.resolve("articles.rss"), Feed.generateRss(site, articles));
 
@@ -172,21 +172,27 @@ public class BlogBuilder {
         }
     }
 
-    private void renderIndexPages(List<Article> articles) throws IOException {
+    private void renderIndexAndPages(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);
+            var pageNumbers = PageNumbers.create(page, lastPage);
 
+            if (page == 1) {
+                var renderedIndex = template.renderIndex(pageNumbers, pageArticles);
+                Files.writeString(outputDirectory.resolve("index.html"), renderedIndex);
+
+                if (!site.separateFirstPage()) continue;
+            }
+
+            var renderedPage = template.renderPage(pageNumbers, pageArticles);
             Files.writeString(pageDirectory.resolve(page + ".html"), renderedPage);
         }
     }

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

@@ -30,6 +30,7 @@ public record Site(
         int articlesPerPage,
 
         boolean templateArticles,
+        boolean separateFirstPage,
 
         Map<String, Object> custom
 ) {
@@ -39,6 +40,7 @@ public record Site(
             "/",
             10,
             false,
+            false,
             Map.of()
     );
 
@@ -57,6 +59,7 @@ public record Site(
         String baseUrl = (String) yaml.getOrDefault("baseUrl", DEFAULT.baseUrl());
         var articlesPerPage = (int) yaml.getOrDefault("articlesPerPage", DEFAULT.articlesPerPage());
         var templateArticles = (boolean) yaml.getOrDefault("templateArticles", DEFAULT.templateArticles());
+        var separateFirstPage = (boolean) yaml.getOrDefault("separateFirstPage", DEFAULT.separateFirstPage());
 
         String directory = DEFAULT.directory();
         if (baseUrl != null) {
@@ -68,7 +71,7 @@ public record Site(
         }
 
         return new Site(
-                name, baseUrl, directory, articlesPerPage, templateArticles, yaml
+                name, baseUrl, directory, articlesPerPage, templateArticles, separateFirstPage, yaml
         );
     }
 }

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

@@ -82,6 +82,30 @@ public class TemplateExtension extends AbstractExtension {
 
                         return site.directory() + path;
                     }
+                },
+                "url_to_page", new Function() {
+                    @Override
+                    public List<String> getArgumentNames() {
+                        return List.of("page");
+                    }
+
+                    @Override
+                    public Object execute(Map<String, Object> args, PebbleTemplate self, EvaluationContext context, int lineNumber) {
+                        var pageObj = args.get("page");
+                        int page;
+
+                        if (pageObj instanceof Number pageNumber) {
+                            page = pageNumber.intValue();
+                        } else {
+                            throw new IllegalArgumentException("\"page\" must be Number");
+                        }
+
+                        if (page == 1 && !site.separateFirstPage()) {
+                            return site.directory();
+                        } else {
+                            return site.directory() + "page/" + page + ".html";
+                        }
+                    }
                 }
         );
     }

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

@@ -11,8 +11,11 @@ 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.error.LoaderException;
 import io.pebbletemplates.pebble.loader.FileLoader;
 import io.pebbletemplates.pebble.template.PebbleTemplate;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 import java.io.IOException;
 import java.io.StringWriter;
@@ -25,11 +28,13 @@ import java.util.Map;
  * using the Pebble templating engine.
  */
 public class TemplateRenderer {
+    private static final Logger LOGGER = LoggerFactory.getLogger(TemplateRenderer.class);
+
     private final Site site;
     private final Minifier minifier;
 
     private final PebbleEngine pebbleEngine;
-    private final PebbleTemplate indexTemplate, articleTemplate;
+    private final PebbleTemplate indexTemplate, articleTemplate, pageTemplate;
 
     /**
      * Constructs a TemplateRenderer instance for rendering templates from the specified directory.
@@ -54,20 +59,49 @@ public class TemplateRenderer {
 
         this.indexTemplate = pebbleEngine.getTemplate("index_template");
         this.articleTemplate = pebbleEngine.getTemplate("article_template");
+
+        var pageTemplate = indexTemplate;
+
+        try {
+            pageTemplate = pebbleEngine.getTemplate("page_template");
+        } catch (LoaderException e) {
+            LOGGER.debug("Template has no page template, using index_template instead");
+        }
+
+        this.pageTemplate = pageTemplate;
     }
 
     /**
-     * Renders the index page using this template.
+     * Renders a page using this template.<br>
+     * This is different from index, as this uses page template.
      *
-     * @param articles the {@link Article}s to be included in the <strong>CURRENT</strong> page
+     * @param pageArticles 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 renderIndexPage(PageNumbers pageNumbers, List<Article> articles) throws IOException {
+    public String renderPage(PageNumbers pageNumbers, List<Article> pageArticles) throws IOException {
         var context = Map.of(
                 "page", pageNumbers,
-                "articles", articles
+                "articles", pageArticles
+        );
+
+        return renderTemplate(pageTemplate, context);
+    }
+
+    /**
+     * Renders the index page using this template.<br>
+     * This is different from rendering page 1, as this uses index template.
+     *
+     * @param pageArticles 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(PageNumbers pageNumbers, List<Article> pageArticles) throws IOException {
+        var context = Map.of(
+                "page", pageNumbers,
+                "articles", pageArticles
         );
 
         return renderTemplate(indexTemplate, context);