LibWeb: Make DOM::Range more suitable for JS.

Author: https://github.com/asynts
Commit: https://github.com/SerenityOS/serenity/commit/10f9c850902
Pull-request: https://github.com/SerenityOS/serenity/pull/4318
Reviewed-by: https://github.com/Lubrsi
Reviewed-by: https://github.com/awesomekling
Reviewed-by: https://github.com/linusg

Libraries/LibWeb/CMakeLists.txt

@@ -36,6 +36,7 @@ set(SOURCES
     DOM/Element.cpp
     DOM/ElementFactory.cpp
     DOM/Event.cpp
+    DOM/Range.cpp
     DOM/EventDispatcher.cpp
     DOM/EventListener.cpp
     DOM/EventTarget.cpp

Libraries/LibWeb/DOM/Position.cpp

@@ -39,24 +39,6 @@ Position::~Position()
 {
 }
 
-Range Range::normalized() const
-{
-    if (!is_valid())
-        return {};
-
-    if (m_start.node() == m_end.node()) {
-        if (m_start.offset() <= m_end.offset())
-            return *this;
-
-        return { m_end, m_start };
-    }
-
-    if (m_start.node()->is_before(*m_end.node()))
-        return *this;
-
-    return { m_end, m_start };
-}
-
 const LogStream& operator<<(const LogStream& stream, const Position& position)
 {
     if (!position.node())

Libraries/LibWeb/DOM/Position.h

@@ -62,38 +62,6 @@ private:
     unsigned m_offset { 0 };
 };
 
-class Range {
-public:
-    Range() = default;
-    Range(const Position& start, const Position& end)
-        : m_start(start)
-        , m_end(end)
-    {
-    }
-
-    bool is_valid() const { return m_start.is_valid() && m_end.is_valid(); }
-
-    void set(const Position& start, const Position& end)
-    {
-        m_start = start;
-        m_end = end;
-    }
-
-    void set_start(const Position& start) { m_start = start; }
-    void set_end(const Position& end) { m_end = end; }
-
-    const Position& start() const { return m_start; }
-    Position& start() { return m_start; }
-
-    const Position& end() const { return m_end; }
-    Position& end() { return m_end; }
-
-    Range normalized() const;
-
-private:
-    Position m_start, m_end;
-};
-
 const LogStream& operator<<(const LogStream&, const Position&);
 
 }

Libraries/LibWeb/DOM/Range.cpp

@@ -0,0 +1,74 @@
+/*
+ * Copyright (c) 2020, the SerenityOS developers.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <LibWeb/DOM/Document.h>
+#include <LibWeb/DOM/Node.h>
+#include <LibWeb/DOM/Range.h>
+
+namespace Web::DOM {
+
+Range::Range(Document& document)
+    : m_start_container(document)
+    , m_start_offset(0)
+    , m_end_container(document)
+    , m_end_offset(0)
+{
+}
+
+Range::Range(Node& start_container, size_t start_offset, Node& end_container, size_t end_offset)
+    : m_start_container(start_container)
+    , m_start_offset(start_offset)
+    , m_end_container(end_container)
+    , m_end_offset(end_offset)
+{
+}
+
+NonnullRefPtr<Range> Range::clone_range() const
+{
+    return adopt(*new Range(const_cast<Node&>(*m_start_container), m_start_offset, const_cast<Node&>(*m_end_container), m_end_offset));
+}
+
+NonnullRefPtr<Range> Range::inverted() const
+{
+    return adopt(*new Range(const_cast<Node&>(*m_end_container), m_end_offset, const_cast<Node&>(*m_start_container), m_start_offset));
+}
+
+NonnullRefPtr<Range> Range::normalized() const
+{
+    if (m_start_container.ptr() == m_end_container.ptr()) {
+        if (m_start_offset <= m_end_offset)
+            return clone_range();
+
+        return inverted();
+    }
+
+    if (m_start_container->is_before(m_end_container))
+        return clone_range();
+
+    return inverted();
+}
+
+}

Libraries/LibWeb/DOM/Range.h

@@ -0,0 +1,87 @@
+/*
+ * Copyright (c) 2020, the SerenityOS developers.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#pragma once
+
+#include <AK/RefCounted.h>
+#include <LibWeb/Bindings/Wrappable.h>
+
+namespace Web::DOM {
+
+class Range final
+    : public RefCounted<Range>
+    , public Bindings::Wrappable {
+public:
+    // using WrapperType = Bindings::RangeWrapper;
+
+    static NonnullRefPtr<Range> create(Document& document)
+    {
+        return adopt(*new Range(document));
+    }
+    static NonnullRefPtr<Range> create(Node& start_container, size_t start_offset, Node& end_container, size_t end_offset)
+    {
+        return adopt(*new Range(start_container, start_offset, end_container, end_offset));
+    }
+
+    Node* start_container() { return m_start_container; }
+    unsigned start_offset() { return m_start_offset; }
+
+    Node* end_container() { return m_end_container; }
+    unsigned end_offset() { return m_end_offset; }
+
+    bool collapsed()
+    {
+        return start_container() == end_container() && start_offset() == end_offset();
+    }
+
+    void set_start(Node& container, JS::Value& offset)
+    {
+        m_start_container = container;
+        m_start_offset = (unsigned)offset.as_i32();
+    }
+
+    void set_end(Node& container, JS::Value& offset)
+    {
+        m_end_container = container;
+        m_end_offset = (unsigned)offset.as_i32();
+    }
+
+    NonnullRefPtr<Range> inverted() const;
+    NonnullRefPtr<Range> normalized() const;
+    NonnullRefPtr<Range> clone_range() const;
+
+private:
+    explicit Range(Document&);
+    Range(Node& start_container, size_t start_offset, Node& end_container, size_t end_offset);
+
+    NonnullRefPtr<Node> m_start_container;
+    unsigned m_start_offset;
+
+    NonnullRefPtr<Node> m_end_container;
+    unsigned m_end_offset;
+};
+
+}

Libraries/LibWeb/Forward.h

@@ -51,10 +51,10 @@ class MouseEvent;
 class Node;
 class ParentNode;
 class Position;
-class Range;
 class Text;
 class Timer;
 class Window;
+class Range;
 enum class QuirksMode;
 }
 

Libraries/LibWeb/Layout/LayoutPosition.cpp

@@ -25,6 +25,7 @@
  */
 
 #include <LibWeb/DOM/Position.h>
+#include <LibWeb/DOM/Range.h>
 #include <LibWeb/Layout/LayoutPosition.h>
 #include <LibWeb/Layout/Node.h>
 
@@ -53,12 +54,14 @@ LayoutRange LayoutRange::normalized() const
     return { m_end, m_start };
 }
 
-DOM::Range LayoutRange::to_dom_range() const
+NonnullRefPtr<DOM::Range> LayoutRange::to_dom_range() const
 {
-    if (!is_valid())
-        return {};
+    ASSERT(is_valid());
 
-    return { m_start.to_dom_position(), m_end.to_dom_position() };
+    auto start = m_start.to_dom_position();
+    auto end = m_end.to_dom_position();
+
+    return DOM::Range::create(*start.node(), start.offset(), *end.node(), end.offset());
 }
 
 }

Libraries/LibWeb/Layout/LayoutPosition.h

@@ -68,7 +68,7 @@ public:
 
     LayoutRange normalized() const;
 
-    DOM::Range to_dom_range() const;
+    NonnullRefPtr<DOM::Range> to_dom_range() const;
 
 private:
     LayoutPosition m_start;

Libraries/LibWeb/Page/EditEventHandler.cpp

@@ -26,6 +26,7 @@
 
 #include <AK/StringBuilder.h>
 #include <LibWeb/DOM/Position.h>
+#include <LibWeb/DOM/Range.h>
 #include <LibWeb/DOM/Text.h>
 #include <LibWeb/Layout/LayoutPosition.h>
 #include <LibWeb/Page/Frame.h>
@@ -39,15 +40,15 @@
 namespace Web {
 
 // This method is quite convoluted but this is necessary to make editing feel intuitive.
-void EditEventHandler::handle_delete(DOM::Range range)
+void EditEventHandler::handle_delete(DOM::Range& range)
 {
-    auto* start = downcast<DOM::Text>(range.start().node());
-    auto* end = downcast<DOM::Text>(range.end().node());
+    auto* start = downcast<DOM::Text>(range.start_container());
+    auto* end = downcast<DOM::Text>(range.end_container());
 
     if (start == end) {
         StringBuilder builder;
-        builder.append(start->data().substring_view(0, range.start().offset()));
-        builder.append(end->data().substring_view(range.end().offset()));
+        builder.append(start->data().substring_view(0, range.start_offset()));
+        builder.append(end->data().substring_view(range.end_offset()));
 
         start->set_data(builder.to_string());
     } else {
@@ -84,8 +85,8 @@ void EditEventHandler::handle_delete(DOM::Range range)
 
         // Join the start and end nodes.
         StringBuilder builder;
-        builder.append(start->data().substring_view(0, range.start().offset()));
-        builder.append(end->data().substring_view(range.end().offset()));
+        builder.append(start->data().substring_view(0, range.start_offset()));
+        builder.append(end->data().substring_view(range.end_offset()));
 
         start->set_data(builder.to_string());
         start->parent()->remove_child(*end);

Libraries/LibWeb/Page/EditEventHandler.h

@@ -39,7 +39,7 @@ public:
 
     virtual ~EditEventHandler() = default;
 
-    virtual void handle_delete(DOM::Range);
+    virtual void handle_delete(DOM::Range&);
     virtual void handle_insert(DOM::Position, u32 code_point);
 
 private:

Libraries/LibWeb/Page/EventHandler.cpp

@@ -28,6 +28,7 @@
 #include <LibGUI/Window.h>
 #include <LibJS/Runtime/Value.h>
 #include <LibWeb/DOM/Document.h>
+#include <LibWeb/DOM/Range.h>
 #include <LibWeb/DOM/Text.h>
 #include <LibWeb/HTML/HTMLAnchorElement.h>
 #include <LibWeb/HTML/HTMLIFrameElement.h>
@@ -346,15 +347,15 @@ bool EventHandler::handle_keydown(KeyCode key, unsigned modifiers, u32 code_poin
     }
 
     if (layout_root()->selection().is_valid()) {
-        auto range = layout_root()->selection().to_dom_range().normalized();
+        auto range = layout_root()->selection().to_dom_range()->normalized();
 
         m_frame.document()->layout_node()->set_selection({});
 
         // FIXME: This doesn't work for some reason?
-        m_frame.set_cursor_position(range.start());
+        m_frame.set_cursor_position({ *range->start_container(), range->start_offset() });
 
         if (key == KeyCode::Key_Backspace || key == KeyCode::Key_Delete) {
-            if (range.start().node()->is_editable()) {
+            if (range->start_container()->is_editable()) {
                 m_edit_event_handler->handle_delete(range);
                 return true;
             }
@@ -375,7 +376,7 @@ bool EventHandler::handle_keydown(KeyCode key, unsigned modifiers, u32 code_poin
                 TODO();
 
             m_frame.cursor_position().set_offset(position.offset() - 1);
-            m_edit_event_handler->handle_delete({ { *position.node(), position.offset() - 1 }, position });
+            m_edit_event_handler->handle_delete(DOM::Range::create(*position.node(), position.offset() - 1, *position.node(), position.offset()));
 
             return true;
         } else if (key == KeyCode::Key_Delete) {
@@ -384,7 +385,7 @@ bool EventHandler::handle_keydown(KeyCode key, unsigned modifiers, u32 code_poin
             if (position.offset() >= downcast<DOM::Text>(position.node())->data().length())
                 TODO();
 
-            m_edit_event_handler->handle_delete({ position, { *position.node(), position.offset() + 1 } });
+            m_edit_event_handler->handle_delete(DOM::Range::create(*position.node(), position.offset(), *position.node(), position.offset() + 1));
 
             return true;
         } else if (key == KeyCode::Key_Right) {