LibWeb: Add a basic DOM::Position class

This will be used for editable content. :^)

Libraries/LibWeb/CMakeLists.txt

@@ -34,6 +34,7 @@ set(SOURCES
     DOM/EventTarget.cpp
     DOM/Node.cpp
     DOM/ParentNode.cpp
+    DOM/Position.cpp
     DOM/TagNames.cpp
     DOM/Text.cpp
     DOM/Timer.cpp

Libraries/LibWeb/DOM/Position.cpp

@@ -0,0 +1,49 @@
+/*
+ * Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
+ * 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/Node.h>
+#include <LibWeb/DOM/Position.h>
+
+namespace Web::DOM {
+
+Position::Position(Node& node, unsigned offset)
+    : m_node(node)
+    , m_offset(offset)
+{
+}
+
+Position::~Position()
+{
+}
+
+const LogStream& operator<<(const LogStream& stream, const Position& position)
+{
+    if (!position.node())
+        return stream << "DOM::Position(nullptr, " << position.offset() << ")";
+    return stream << "DOM::Position(" << position.node()->node_name() << "{" << position.node() << "}, " << position.offset() << ")";
+}
+
+}

Libraries/LibWeb/DOM/Position.h

@@ -0,0 +1,63 @@
+/*
+ * Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
+ * 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/RefPtr.h>
+#include <LibWeb/Forward.h>
+
+namespace Web::DOM {
+
+class Position {
+public:
+    Position() { }
+    Position(Node&, unsigned offset);
+
+    ~Position();
+
+    Node* node() { return m_node; }
+    const Node* node() const { return m_node; }
+
+    unsigned offset() const { return m_offset; }
+
+    bool operator==(const Position& other) const
+    {
+        return m_node == other.m_node && m_offset == other.m_offset;
+    }
+
+    bool operator!=(const Position& other) const
+    {
+        return !(*this == other);
+    }
+
+private:
+    RefPtr<Node> m_node;
+    unsigned m_offset { 0 };
+};
+
+const LogStream& operator<<(const LogStream&, const Position&);
+
+}

Libraries/LibWeb/Forward.h

@@ -45,6 +45,7 @@ class EventTarget;
 class MouseEvent;
 class Node;
 class ParentNode;
+class Position;
 class Text;
 class Timer;
 class Window;