LibVT+Terminal: Add color scheme support

This commit introduces color scheme support to Terminal. These are found
in `/res/terminal_colors` and the default color scheme can be set in
`~/.config/Terminal.ini`. Furthermore, a combo box is added for
setting the color scheme at runtime.

The previously used default color scheme has been added to
`/res/terminal-colors/Default.ini`.

To make the implementation more compatible with other color schemes,
`TerminalWidget` now supports overriding the default foreground and
background colors.

4 files changed, 104 insertions, 5 deletions

diff --git a/Userland/Applications/Terminal/TerminalSettingsWindow.gml b/Userland/Applications/Terminal/TerminalSettingsWindow.gml
index 07b8400c56..6c906fd463 100644
--- a/Userland/Applications/Terminal/TerminalSettingsWindow.gml
+++ b/Userland/Applications/Terminal/TerminalSettingsWindow.gml
@@ -60,4 +60,17 @@
             orientation: "Horizontal"
         }
     }
+
+    @GUI::GroupBox {
+        title: "Color scheme"
+        shrink_to_fit: true
+
+        layout: @GUI::VerticalBoxLayout {
+            margins: [6, 16, 6, 6]
+        }
+
+        @GUI::ComboBox {
+            name: "color_scheme_combo"
+        }
+    }
 }
diff --git a/Userland/Applications/Terminal/main.cpp b/Userland/Applications/Terminal/main.cpp
index 846b0ffdd2..dd8fc9e325 100644
--- a/Userland/Applications/Terminal/main.cpp
+++ b/Userland/Applications/Terminal/main.cpp
@@ -4,10 +4,12 @@
  * SPDX-License-Identifier: BSD-2-Clause
  */
 
+#include <AK/QuickSort.h>
 #include <AK/URL.h>
 #include <Applications/Terminal/TerminalSettingsWindowGML.h>
 #include <LibCore/ArgsParser.h>
 #include <LibCore/ConfigFile.h>
+#include <LibCore/DirIterator.h>
 #include <LibCore/File.h>
 #include <LibDesktop/Launcher.h>
 #include <LibGUI/Action.h>
@@ -16,9 +18,11 @@
 #include <LibGUI/BoxLayout.h>
 #include <LibGUI/Button.h>
 #include <LibGUI/CheckBox.h>
+#include <LibGUI/ComboBox.h>
 #include <LibGUI/Event.h>
 #include <LibGUI/FontPicker.h>
 #include <LibGUI/Icon.h>
+#include <LibGUI/ItemListModel.h>
 #include <LibGUI/Menu.h>
 #include <LibGUI/Menubar.h>
 #include <LibGUI/OpacitySlider.h>
@@ -105,7 +109,7 @@ static RefPtr<GUI::Window> create_settings_window(VT::TerminalWidget& terminal)
     window->set_window_type(GUI::WindowType::ToolWindow);
     window->set_title("Terminal settings");
     window->set_resizable(false);
-    window->resize(200, 210);
+    window->resize(200, 240);
     window->center_within(*terminal.window());
 
     auto& settings = window->set_main_widget<GUI::Widget>();
@@ -149,6 +153,25 @@ static RefPtr<GUI::Window> create_settings_window(VT::TerminalWidget& terminal)
         terminal.set_max_history_size(value);
     };
 
+    // The settings window takes a reference to this vector, so it needs to outlive this scope.
+    // As long as we ensure that only one settings window may be open at a time (which we do),
+    // this should cause no problems.
+    static Vector<String> color_scheme_names;
+    color_scheme_names.clear();
+    Core::DirIterator iterator("/res/terminal-colors", Core::DirIterator::SkipParentAndBaseDir);
+    while (iterator.has_next()) {
+        auto path = iterator.next_path();
+        path.replace(".ini", "");
+        color_scheme_names.append(path);
+    }
+    quick_sort(color_scheme_names);
+    auto& color_scheme_combo = *settings.find_descendant_of_type_named<GUI::ComboBox>("color_scheme_combo");
+    color_scheme_combo.set_only_allow_values_from_model(true);
+    color_scheme_combo.set_model(*GUI::ItemListModel<String>::create(color_scheme_names));
+    color_scheme_combo.set_selected_index(color_scheme_names.find_first_index(terminal.color_scheme_name()).value());
+    color_scheme_combo.on_change = [&](auto&, const GUI::ModelIndex& index) {
+        terminal.set_color_scheme(index.data().as_string());
+    };
     return window;
 }
 
diff --git a/Userland/Libraries/LibVT/TerminalWidget.cpp b/Userland/Libraries/LibVT/TerminalWidget.cpp
index 6998a8a96d..f010e8ed69 100644
--- a/Userland/Libraries/LibVT/TerminalWidget.cpp
+++ b/Userland/Libraries/LibVT/TerminalWidget.cpp
@@ -79,6 +79,9 @@ TerminalWidget::TerminalWidget(int ptm_fd, bool automatic_size_policy, RefPtr<Co
     , m_automatic_size_policy(automatic_size_policy)
     , m_config(move(config))
 {
+    static_assert(sizeof(m_colors) == sizeof(xterm_colors));
+    memcpy(m_colors, xterm_colors, sizeof(m_colors));
+
     set_override_cursor(Gfx::StandardCursor::IBeam);
     set_focus_policy(GUI::FocusPolicy::StrongFocus);
     set_accepts_emoji_input(true);
@@ -147,6 +150,8 @@ TerminalWidget::TerminalWidget(int ptm_fd, bool automatic_size_policy, RefPtr<Co
 
     update_copy_action();
     update_paste_action();
+
+    set_color_scheme(m_config->read_entry("Window", "ColorScheme", "Default"));
 }
 
 TerminalWidget::~TerminalWidget()
@@ -1135,6 +1140,54 @@ void TerminalWidget::update_paste_action()
     m_paste_action->set_enabled(GUI::Clipboard::the().mime_type().starts_with("text/") && !GUI::Clipboard::the().data().is_empty());
 }
 
+void TerminalWidget::set_color_scheme(const StringView& name)
+{
+    if (name.contains('/')) {
+        dbgln("Shenanigans! Color scheme names can't contain slashes.");
+        return;
+    }
+
+    m_color_scheme_name = name;
+
+    constexpr StringView color_names[] = {
+        "Black",
+        "Red",
+        "Green",
+        "Yellow",
+        "Blue",
+        "Magenta",
+        "Cyan",
+        "White"
+    };
+
+    auto color_config = Core::ConfigFile::open(String::formatted("/res/terminal-colors/{}.ini", name));
+
+    auto default_background = Gfx::Color::from_string(color_config->read_entry("Primary", "Background"));
+    if (default_background.has_value())
+        m_default_background_color = default_background.value();
+    else
+        m_default_background_color = Gfx::Color::from_rgb(m_colors[(u8)VT::Color::ANSIColor::Black]);
+
+    auto default_foreground = Gfx::Color::from_string(color_config->read_entry("Primary", "Foreground"));
+    if (default_foreground.has_value())
+        m_default_foreground_color = default_foreground.value();
+    else
+        m_default_foreground_color = Gfx::Color::from_rgb(m_colors[(u8)VT::Color::ANSIColor::White]);
+
+    for (u8 color_idx = 0; color_idx < 8; ++color_idx) {
+        auto rgb = Gfx::Color::from_string(color_config->read_entry("Normal", color_names[color_idx]));
+        if (rgb.has_value())
+            m_colors[color_idx] = rgb.value().value();
+    }
+
+    for (u8 color_idx = 0; color_idx < 8; ++color_idx) {
+        auto rgb = Gfx::Color::from_string(color_config->read_entry("Bright", color_names[color_idx]));
+        if (rgb.has_value())
+            m_colors[color_idx + 8] = rgb.value().value();
+    }
+    update();
+}
+
 Gfx::IntSize TerminalWidget::widget_size_for_font(const Gfx::Font& font) const
 {
     return {
@@ -1149,15 +1202,15 @@ Gfx::Color TerminalWidget::terminal_color_to_rgb(VT::Color color)
     case VT::Color::Kind::RGB:
         return Gfx::Color::from_rgb(color.as_rgb());
     case VT::Color::Kind::Indexed:
-        return Gfx::Color::from_rgb(xterm_colors[color.as_indexed()]);
+        return Gfx::Color::from_rgb(m_colors[color.as_indexed()]);
     case VT::Color::Kind::Named: {
         auto ansi = color.as_named();
         if ((u16)ansi < 256)
-            return Gfx::Color::from_rgb(xterm_colors[(u16)ansi]);
+            return Gfx::Color::from_rgb(m_colors[(u16)ansi]);
         else if (ansi == VT::Color::ANSIColor::DefaultForeground)
-            return Gfx::Color::from_rgb(xterm_colors[7]);
+            return m_default_foreground_color;
         else if (ansi == VT::Color::ANSIColor::DefaultBackground)
-            return Gfx::Color::from_rgb(xterm_colors[0]);
+            return m_default_background_color;
         else
             VERIFY_NOT_REACHED();
     }
diff --git a/Userland/Libraries/LibVT/TerminalWidget.h b/Userland/Libraries/LibVT/TerminalWidget.h
index 39d8a7f2e9..5d4307e651 100644
--- a/Userland/Libraries/LibVT/TerminalWidget.h
+++ b/Userland/Libraries/LibVT/TerminalWidget.h
@@ -81,6 +81,8 @@ public:
     void paste();
     void clear_including_history();
 
+    const StringView color_scheme_name() const { return m_color_scheme_name; }
+
     Function<void(const StringView&)> on_title_change;
     Function<void(const Gfx::IntSize&)> on_terminal_size_change;
     Function<void()> on_command_exit;
@@ -91,6 +93,8 @@ public:
 
     void set_font_and_resize_to_fit(const Gfx::Font&);
 
+    void set_color_scheme(const StringView&);
+
 private:
     // ^GUI::Widget
     virtual void event(Core::Event&) override;
@@ -157,6 +161,12 @@ private:
     // Snapshot of m_hovered_href when opening a context menu for a hyperlink.
     String m_context_menu_href;
 
+    unsigned m_colors[256];
+    Gfx::Color m_default_foreground_color;
+    Gfx::Color m_default_background_color;
+
+    String m_color_scheme_name;
+
     BellMode m_bell_mode { BellMode::Visible };
     bool m_alt_key_held { false };
     bool m_rectangle_selection { false };