LibManual: Associate SubsectionNode with similarly named markdown file

For a subsection named `Foo` with a markdown file `Foo.md` in the same
directory, the document `Foo.md` will be returned when the subsection is
selected.

This prevents PageNodes and SubsectionNodes from sharing the same
name, which fixes an issue in Help where subsections could not be
navigated.

3 files changed, 34 insertions, 32 deletions

diff --git a/Userland/Libraries/LibManual/SectionNode.cpp b/Userland/Libraries/LibManual/SectionNode.cpp
index 150f960f32..cc2a39f07a 100644
--- a/Userland/Libraries/LibManual/SectionNode.cpp
+++ b/Userland/Libraries/LibManual/SectionNode.cpp
@@ -8,6 +8,7 @@
 #include "PageNode.h"
 #include "Path.h"
 #include "SubsectionNode.h"
+#include <AK/HashTable.h>
 #include <AK/LexicalPath.h>
 #include <AK/QuickSort.h>
 #include <LibCore/DirIterator.h>
@@ -43,7 +44,16 @@ ErrorOr<void> SectionNode::reify_if_needed() const
     m_reified = true;
 
     auto own_path = TRY(path());
-    Core::DirIterator dir_iter { own_path.to_deprecated_string(), Core::DirIterator::Flags::SkipDots };
+    Core::DirIterator dir_iterator { own_path.to_deprecated_string(), Core::DirIterator::Flags::SkipDots };
+    Vector<DeprecatedString> directories;
+    HashTable<DeprecatedString> files;
+    while (dir_iterator.has_next()) {
+        auto entry = dir_iterator.next();
+        if (entry->type == Core::DirectoryEntry::Type::Directory)
+            TRY(directories.try_append(entry->name));
+        else if (entry->type == Core::DirectoryEntry::Type::File && entry->name.ends_with(".md"sv, CaseSensitivity::CaseInsensitive))
+            TRY(files.try_set(entry->name));
+    }
 
     struct Child {
         NonnullRefPtr<Node const> node;
@@ -51,18 +61,21 @@ ErrorOr<void> SectionNode::reify_if_needed() const
     };
     Vector<Child> children;
 
-    while (dir_iter.has_next()) {
-        LexicalPath lexical_path(dir_iter.next_path());
-        if (lexical_path.extension() != "md") {
-            if (FileSystem::is_directory(LexicalPath::absolute_path(own_path.to_deprecated_string(), lexical_path.string()))) {
-                dbgln("Found subsection {}", lexical_path);
-                children.append({ .node = TRY(try_make_ref_counted<SubsectionNode>(*this, lexical_path.title())),
-                    .name_for_sorting = TRY(String::from_utf8(lexical_path.title())) });
-            }
-        } else {
-            children.append({ .node = TRY(try_make_ref_counted<PageNode>(*this, TRY(String::from_utf8(lexical_path.title())))),
-                .name_for_sorting = TRY(String::from_utf8(lexical_path.title())) });
-        }
+    for (auto const& directory : directories) {
+        LexicalPath lexical_path(directory);
+        RefPtr<PageNode> associated_page;
+        auto matching_page_name = DeprecatedString::formatted("{}.md", directory);
+        if (files.remove(matching_page_name))
+            associated_page = TRY(try_make_ref_counted<PageNode>(*this, TRY(String::from_utf8(lexical_path.title()))));
+
+        TRY(children.try_append({ .node = TRY(try_make_ref_counted<SubsectionNode>(*this, lexical_path.title(), associated_page)),
+            .name_for_sorting = TRY(String::from_utf8(lexical_path.title())) }));
+    }
+
+    for (auto const& file : files) {
+        LexicalPath lexical_path(file);
+        children.append({ .node = TRY(try_make_ref_counted<PageNode>(*this, TRY(String::from_utf8(lexical_path.title())))),
+            .name_for_sorting = TRY(String::from_utf8(lexical_path.title())) });
     }
 
     quick_sort(children, [](auto const& a, auto const& b) { return a.name_for_sorting < b.name_for_sorting; });
diff --git a/Userland/Libraries/LibManual/SubsectionNode.cpp b/Userland/Libraries/LibManual/SubsectionNode.cpp
index cb1e6d44fb..f5535a1bf8 100644
--- a/Userland/Libraries/LibManual/SubsectionNode.cpp
+++ b/Userland/Libraries/LibManual/SubsectionNode.cpp
@@ -10,31 +10,16 @@
 
 namespace Manual {
 
-SubsectionNode::SubsectionNode(NonnullRefPtr<SectionNode const> parent, StringView name)
+SubsectionNode::SubsectionNode(NonnullRefPtr<SectionNode const> parent, StringView name, RefPtr<PageNode> page)
     : SectionNode(name, name)
     , m_parent(move(parent))
+    , m_page(move(page))
 {
 }
 
 Node const* SubsectionNode::parent() const { return m_parent; }
 
-PageNode const* SubsectionNode::document() const
-{
-    auto maybe_siblings = parent()->children();
-    if (maybe_siblings.is_error())
-        return nullptr;
-    auto siblings = maybe_siblings.release_value();
-    for (auto const& sibling : siblings) {
-        if (&*sibling == this)
-            continue;
-        auto sibling_name = sibling->name();
-        if (sibling_name.is_error())
-            continue;
-        if (sibling_name.value() == m_name && is<PageNode>(*sibling))
-            return static_cast<PageNode const*>(&*sibling);
-    }
-    return nullptr;
-}
+PageNode const* SubsectionNode::document() const { return m_page; }
 
 ErrorOr<String> SubsectionNode::name() const { return m_name; }
 
diff --git a/Userland/Libraries/LibManual/SubsectionNode.h b/Userland/Libraries/LibManual/SubsectionNode.h
index 93a4334f97..4ab6fda183 100644
--- a/Userland/Libraries/LibManual/SubsectionNode.h
+++ b/Userland/Libraries/LibManual/SubsectionNode.h
@@ -6,6 +6,7 @@
 
 #pragma once
 
+#include <LibManual/PageNode.h>
 #include <LibManual/SectionNode.h>
 
 namespace Manual {
@@ -13,7 +14,7 @@ namespace Manual {
 // A non-toplevel (i.e. not numbered) manual section.
 class SubsectionNode : public SectionNode {
 public:
-    SubsectionNode(NonnullRefPtr<SectionNode const> parent, StringView name);
+    SubsectionNode(NonnullRefPtr<SectionNode const> parent, StringView name, RefPtr<PageNode> page = {});
     virtual ~SubsectionNode() = default;
 
     virtual Node const* parent() const override;
@@ -23,6 +24,9 @@ public:
 
 protected:
     NonnullRefPtr<SectionNode const> m_parent;
+
+private:
+    RefPtr<PageNode> m_page;
 };
 
 }