From 496d0ac46264e6bf7d85d3f69865123714590a51 Mon Sep 17 00:00:00 2001
From: Jens Pelzetter <jens@jp-digital.de>
Date: Wed, 2 Mar 2022 19:27:57 +0100
Subject: [PATCH] Use URL params for sections

---
 .../pages/models/MultiPartArticleModel.java   | 57 +++++++++----------
 1 file changed, 28 insertions(+), 29 deletions(-)

diff --git a/ccm-cms/src/main/java/org/librecms/pages/models/MultiPartArticleModel.java b/ccm-cms/src/main/java/org/librecms/pages/models/MultiPartArticleModel.java
index f9b224bc5..65b00bea8 100644
--- a/ccm-cms/src/main/java/org/librecms/pages/models/MultiPartArticleModel.java
+++ b/ccm-cms/src/main/java/org/librecms/pages/models/MultiPartArticleModel.java
@@ -35,6 +35,7 @@ import org.librecms.contentsection.ContentItem;
 import org.librecms.contenttypes.MultiPartArticle;
 import org.librecms.contenttypes.MultiPartArticleSection;
 
+import java.net.URL;
 import java.util.ArrayList;
 
 /**
@@ -45,6 +46,8 @@ import java.util.ArrayList;
 @Named("CmsPagesMultiPartArticleModel")
 public class MultiPartArticleModel implements ProcessesContentItem {
 
+    private static final String MPA_SECTION_QUERY_PARAM = "mpa_section";
+
     @Inject
     private ContentItemModel contentItemModel;
 
@@ -154,7 +157,7 @@ public class MultiPartArticleModel implements ProcessesContentItem {
                 .orElse(Collections.emptyList());
 
             sectionLinks = buildSectionLinks();
-            
+
             final int currentSection = readCurrentSection();
             if (mpa.getSections().size() < currentSection) {
                 throw new WebApplicationException(
@@ -197,12 +200,15 @@ public class MultiPartArticleModel implements ProcessesContentItem {
     }
 
     private int readCurrentSection() {
-        if (pageUrlModel.getPath().matches(".*/@sections/[0-9]*$")) {
-            final String[] tokens = pageUrlModel.getPath().split("/");
-            return Integer.valueOf(tokens[tokens.length - 1]) - 1;
-        } else {
-            return 0;
-        }
+        return Optional
+            .ofNullable(
+                pageUrlModel.getQueryParameters().get(
+                    MPA_SECTION_QUERY_PARAM
+                )
+            )
+            .filter(value -> value.matches("\\d*"))
+            .map(value -> Integer.parseInt(value))
+            .orElse(0);
     }
 
     @Transactional(Transactional.TxType.REQUIRED)
@@ -227,42 +233,35 @@ public class MultiPartArticleModel implements ProcessesContentItem {
 
     @Transactional(Transactional.TxType.REQUIRED)
     private List<String> buildSectionLinks() {
-        final String pathWithoutSections;
-        if (pageUrlModel.getPath().matches(".*/@sections/[0-9]*$")) {
-            final String path = pageUrlModel.getPath();
-            pathWithoutSections = path.substring(
-                0,
-                path.lastIndexOf("/@sections") + 1
-            );
-        } else {
-            pathWithoutSections = pageUrlModel.getPath();
-        }
-
+        final int size = sectionTitles.size();
         final List<String> sectionLinksList = new ArrayList<>();
-        for (int i = 0; i < sectionTitles.size(); i++) {
+        for (int i = 0; i < size; i++) {
             sectionLinksList.add(
                 String.format(
-                    "%s/@sections/%d?%s",
-                    pathWithoutSections,
-                    i,
+                    "?%s&%s=%d",
                     pageUrlModel
                         .getQueryParameters()
                         .entrySet()
                         .stream()
+                        .filter(
+                            entry
+                            -> !MPA_SECTION_QUERY_PARAM
+                                .equals(
+                                    entry.getKey()
+                                )
+                        )
                         .map(
                             entry -> String.format(
-                                "%s=%s",
-                                entry.getKey(),
-                                entry.getValue()
+                                "%s=%s", entry.getKey(), entry.getValue()
                             )
                         )
-                        .collect(
-                            Collectors.joining("&")
-                        )
+                        .collect(Collectors.joining("&")),
+                    MPA_SECTION_QUERY_PARAM,
+                    i
                 )
             );
         }
-
+        
         return sectionLinksList;
     }