LibVT: Create VT::Range and use it to replace selection start / end

Based on GUI::TextRange, This is both a bit more expressive and will
eventually be used for searching within the terminal

Libraries/LibVT/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 <LibVT/Position.h>
+
+namespace VT {
+
+class Range {
+public:
+    Range() { }
+    Range(const VT::Position& start, const VT::Position& end)
+        : m_start(start)
+        , m_end(end)
+    {
+    }
+
+    bool is_valid() const { return m_start.is_valid() && m_end.is_valid(); }
+    void clear()
+    {
+        m_start = {};
+        m_end = {};
+    }
+
+    VT::Position& start() { return m_start; }
+    VT::Position& end() { return m_end; }
+    const VT::Position& start() const { return m_start; }
+    const VT::Position& end() const { return m_end; }
+
+    Range normalized() const { return Range(normalized_start(), normalized_end()); }
+
+    void set_start(const VT::Position& position) { m_start = position; }
+    void set_end(const VT::Position& position) { m_end = position; }
+
+    void set(const VT::Position& start, const VT::Position& end)
+    {
+        m_start = start;
+        m_end = end;
+    }
+
+    bool operator==(const Range& other) const
+    {
+        return m_start == other.m_start && m_end == other.m_end;
+    }
+
+    bool contains(const VT::Position& position) const
+    {
+        if (!(position.row() > m_start.row() || (position.row() == m_start.row() && position.column() >= m_start.column())))
+            return false;
+        if (!(position.row() < m_end.row() || (position.row() == m_end.row() && position.column() <= m_end.column())))
+            return false;
+        return true;
+    }
+
+private:
+    VT::Position normalized_start() const { return m_start < m_end ? m_start : m_end; }
+    VT::Position normalized_end() const { return m_start < m_end ? m_end : m_start; }
+
+    VT::Position m_start;
+    VT::Position m_end;
+};
+
+};

Libraries/LibVT/TerminalWidget.cpp

@@ -255,11 +255,11 @@ void TerminalWidget::keydown_event(GUI::KeyEvent& event)
 
     // Clear the selection if we type in/behind it.
     auto future_cursor_column = (event.key() == KeyCode::Key_Backspace) ? m_terminal.cursor_column() - 1 : m_terminal.cursor_column();
-    auto min_selection_row = min(m_selection_start.row(), m_selection_end.row());
+    auto min_selection_row = min(m_selection.start().row(), m_selection.end().row());
-    auto max_selection_row = max(m_selection_start.row(), m_selection_end.row());
+    auto max_selection_row = max(m_selection.start().row(), m_selection.end().row());
 
     if (future_cursor_column <= last_selection_column_on_row(m_terminal.cursor_row()) && m_terminal.cursor_row() >= min_selection_row && m_terminal.cursor_row() <= max_selection_row) {
-        m_selection_end = {};
+        m_selection.set_end({});
         update_copy_action();
         update();
     }
@@ -491,23 +491,16 @@ void TerminalWidget::set_opacity(u8 new_opacity)
     force_repaint();
 }
 
-VT::Position TerminalWidget::normalized_selection_start() const
-{
-    if (m_selection_start < m_selection_end)
-        return m_selection_start;
-    return m_selection_end;
-}
-
-VT::Position TerminalWidget::normalized_selection_end() const
-{
-    if (m_selection_start < m_selection_end)
-        return m_selection_end;
-    return m_selection_start;
-}
-
 bool TerminalWidget::has_selection() const
 {
-    return m_selection_start.is_valid() && m_selection_end.is_valid();
+    return m_selection.is_valid();
+}
+
+void TerminalWidget::set_selection(const VT::Range& selection)
+{
+    m_selection = selection;
+    update_copy_action();
+    update();
 }
 
 bool TerminalWidget::selection_contains(const VT::Position& position) const
@@ -516,6 +509,8 @@ bool TerminalWidget::selection_contains(const VT::Position& position) const
         return false;
 
     if (m_rectangle_selection) {
+        auto m_selection_start = m_selection.start();
+        auto m_selection_end = m_selection.end();
         auto min_selection_column = min(m_selection_start.column(), m_selection_end.column());
         auto max_selection_column = max(m_selection_start.column(), m_selection_end.column());
         auto min_selection_row = min(m_selection_start.row(), m_selection_end.row());
@@ -524,7 +519,8 @@ bool TerminalWidget::selection_contains(const VT::Position& position) const
         return position.column() >= min_selection_column && position.column() <= max_selection_column && position.row() >= min_selection_row && position.row() <= max_selection_row;
     }
 
-    return position >= normalized_selection_start() && position <= normalized_selection_end();
+    auto normalized_selection = m_selection.normalized();
+    return position >= normalized_selection.start() && position <= normalized_selection.end();
 }
 
 VT::Position TerminalWidget::buffer_position_at(const Gfx::IntPoint& position) const
@@ -564,8 +560,7 @@ void TerminalWidget::doubleclick_event(GUI::MouseEvent& event)
             end_column = column;
         }
 
-        m_selection_start = { position.row(), start_column };
+        m_selection.set({ position.row(), start_column }, { position.row(), end_column });
-        m_selection_end = { position.row(), end_column };
         update_copy_action();
     }
     GUI::Frame::doubleclick_event(event);
@@ -631,11 +626,9 @@ void TerminalWidget::mousedown_event(GUI::MouseEvent& event)
             int end_column = m_terminal.columns() - 1;
 
             auto position = buffer_position_at(event.position());
-            m_selection_start = { position.row(), start_column };
+            m_selection.set({ position.row(), start_column }, { position.row(), end_column });
-            m_selection_end = { position.row(), end_column };
         } else {
-            m_selection_start = buffer_position_at(event.position());
+            m_selection.set(buffer_position_at(event.position()), {});
-            m_selection_end = {};
         }
         if (m_alt_key_held)
             m_rectangle_selection = true;
@@ -700,9 +693,9 @@ void TerminalWidget::mousemove_event(GUI::MouseEvent& event)
     else
         m_auto_scroll_direction = AutoScrollDirection::None;
 
-    auto old_selection_end = m_selection_end;
+    VT::Position old_selection_end = m_selection.end();
-    m_selection_end = position;
+    m_selection.set_end(position);
-    if (old_selection_end != m_selection_end) {
+    if (old_selection_end != m_selection.end()) {
         update_copy_action();
         update();
     }
@@ -744,8 +737,10 @@ void TerminalWidget::set_scroll_length(int length)
 String TerminalWidget::selected_text() const
 {
     StringBuilder builder;
-    auto start = normalized_selection_start();
+
-    auto end = normalized_selection_end();
+    auto normalized_selection = m_selection.normalized();
+    auto start = normalized_selection.start();
+    auto end = normalized_selection.end();
 
     for (int row = start.row(); row <= end.row(); ++row) {
         int first_column = first_selection_column_on_row(row);
@@ -774,12 +769,14 @@ String TerminalWidget::selected_text() const
 
 int TerminalWidget::first_selection_column_on_row(int row) const
 {
-    return row == normalized_selection_start().row() || m_rectangle_selection ? normalized_selection_start().column() : 0;
+    auto normalized_selection_start = m_selection.normalized().start();
+    return row == normalized_selection_start.row() || m_rectangle_selection ? normalized_selection_start.column() : 0;
 }
 
 int TerminalWidget::last_selection_column_on_row(int row) const
 {
-    return row == normalized_selection_end().row() || m_rectangle_selection ? normalized_selection_end().column() : m_terminal.columns() - 1;
+    auto normalized_selection_end = m_selection.normalized().end();
+    return row == normalized_selection_end.row() || m_rectangle_selection ? normalized_selection_end.column() : m_terminal.columns() - 1;
 }
 
 void TerminalWidget::terminal_history_changed()

Libraries/LibVT/TerminalWidget.h

@@ -34,6 +34,7 @@
 #include <LibGUI/Frame.h>
 #include <LibGfx/Bitmap.h>
 #include <LibGfx/Rect.h>
+#include <LibVT/Range.h>
 #include <LibVT/Terminal.h>
 
 class TerminalWidget final : public GUI::Frame
@@ -76,9 +77,9 @@ public:
     bool has_selection() const;
     bool selection_contains(const VT::Position&) const;
     String selected_text() const;
+    VT::Range normalized_selection() const { return m_selection.normalized(); }
+    void set_selection(const VT::Range& selection);
     VT::Position buffer_position_at(const Gfx::IntPoint&) const;
-    VT::Position normalized_selection_start() const;
-    VT::Position normalized_selection_end() const;
 
     void scroll_to_bottom();
 
@@ -146,8 +147,7 @@ private:
 
     VT::Terminal m_terminal;
 
-    VT::Position m_selection_start;
+    VT::Range m_selection;
-    VT::Position m_selection_end;
 
     String m_hovered_href;
     String m_hovered_href_id;