LibGUI+Applications: Move abstract ThemeEditor preview to LibGUI

This allows most of the theme preview code to be reused by similar
theme preview widgets.

3 files changed, 245 insertions, 2 deletions

diff --git a/Userland/Libraries/LibGUI/AbstractThemePreview.cpp b/Userland/Libraries/LibGUI/AbstractThemePreview.cpp
new file mode 100644
index 0000000000..7684f40420
--- /dev/null
+++ b/Userland/Libraries/LibGUI/AbstractThemePreview.cpp
@@ -0,0 +1,160 @@
+/*
+ * Copyright (c) 2020, Andreas Kling <kling@serenityos.org>
+ * Copyright (c) 2021, Sam Atkins <atkinssj@serenityos.org>
+ * Copyright (c) 2021, Antonio Di Stefano <tonio9681@gmail.com>
+ * Copyright (c) 2022, the SerenityOS developers.
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <AK/Array.h>
+#include <AK/LexicalPath.h>
+#include <AK/StringView.h>
+#include <LibCore/ConfigFile.h>
+#include <LibCore/File.h>
+#include <LibGUI/AbstractThemePreview.h>
+#include <LibGUI/Painter.h>
+#include <LibGfx/Bitmap.h>
+
+namespace GUI {
+
+AbstractThemePreview::AbstractThemePreview(Gfx::Palette const& preview_palette)
+    : m_preview_palette(preview_palette)
+{
+    m_active_window_icon = Gfx::Bitmap::try_load_from_file("/res/icons/16x16/window.png").release_value_but_fixme_should_propagate_errors();
+    m_inactive_window_icon = Gfx::Bitmap::try_load_from_file("/res/icons/16x16/window.png").release_value_but_fixme_should_propagate_errors();
+
+    m_default_close_bitmap = Gfx::Bitmap::try_load_from_file("/res/icons/16x16/window-close.png").release_value_but_fixme_should_propagate_errors();
+    m_default_maximize_bitmap = Gfx::Bitmap::try_load_from_file("/res/icons/16x16/upward-triangle.png").release_value_but_fixme_should_propagate_errors();
+    m_default_minimize_bitmap = Gfx::Bitmap::try_load_from_file("/res/icons/16x16/downward-triangle.png").release_value_but_fixme_should_propagate_errors();
+
+    VERIFY(m_active_window_icon);
+    VERIFY(m_inactive_window_icon);
+    VERIFY(m_default_close_bitmap);
+    VERIFY(m_default_maximize_bitmap);
+    VERIFY(m_default_minimize_bitmap);
+
+    load_theme_bitmaps();
+}
+
+void AbstractThemePreview::load_theme_bitmaps()
+{
+    auto load_bitmap = [](String const& path, String& last_path, RefPtr<Gfx::Bitmap>& bitmap) {
+        if (path.is_empty()) {
+            last_path = String::empty();
+            bitmap = nullptr;
+        } else if (last_path != path) {
+            auto bitmap_or_error = Gfx::Bitmap::try_load_from_file(path);
+            if (bitmap_or_error.is_error()) {
+                last_path = String::empty();
+                bitmap = nullptr;
+            } else {
+                last_path = path;
+                bitmap = bitmap_or_error.release_value();
+            }
+        }
+    };
+
+    auto buttons_path = m_preview_palette.title_button_icons_path();
+
+    load_bitmap(LexicalPath::absolute_path(buttons_path, "window-close.png"), m_last_close_path, m_close_bitmap);
+    load_bitmap(LexicalPath::absolute_path(buttons_path, "window-maximize.png"), m_last_maximize_path, m_maximize_bitmap);
+    load_bitmap(LexicalPath::absolute_path(buttons_path, "window-minimize.png"), m_last_minimize_path, m_minimize_bitmap);
+
+    load_bitmap(m_preview_palette.active_window_shadow_path(), m_last_active_window_shadow_path, m_active_window_shadow);
+    load_bitmap(m_preview_palette.inactive_window_shadow_path(), m_last_inactive_window_shadow_path, m_inactive_window_shadow);
+    load_bitmap(m_preview_palette.menu_shadow_path(), m_last_menu_shadow_path, m_menu_shadow);
+    load_bitmap(m_preview_palette.taskbar_shadow_path(), m_last_taskbar_shadow_path, m_taskbar_shadow);
+    load_bitmap(m_preview_palette.tooltip_shadow_path(), m_last_tooltip_shadow_path, m_tooltip_shadow);
+}
+
+void AbstractThemePreview::set_preview_palette(Gfx::Palette const& palette)
+{
+    m_preview_palette = palette;
+    if (on_palette_change) {
+        on_palette_change();
+    }
+    load_theme_bitmaps();
+    update();
+}
+
+void AbstractThemePreview::set_theme_from_file(Core::File& file)
+{
+    auto config_file = Core::ConfigFile::open(file.filename(), file.leak_fd()).release_value_but_fixme_should_propagate_errors();
+    auto theme = Gfx::load_system_theme(config_file);
+    VERIFY(theme.is_valid());
+
+    m_preview_palette = Gfx::Palette(Gfx::PaletteImpl::create_with_anonymous_buffer(theme));
+    set_preview_palette(m_preview_palette);
+    if (on_theme_load_from_file)
+        on_theme_load_from_file(file.filename());
+}
+
+void AbstractThemePreview::paint_window(StringView title, Gfx::IntRect const& rect, Gfx::WindowTheme::WindowState state, Gfx::Bitmap const& icon, int button_count)
+{
+    GUI::Painter painter(*this);
+
+    struct Button {
+        Gfx::IntRect rect;
+        RefPtr<Gfx::Bitmap> bitmap;
+    };
+
+    int window_button_width = m_preview_palette.window_title_button_width();
+    int window_button_height = m_preview_palette.window_title_button_height();
+    auto titlebar_text_rect = Gfx::WindowTheme::current().titlebar_text_rect(Gfx::WindowTheme::WindowType::Normal, rect, m_preview_palette);
+    int pos = titlebar_text_rect.right() + 1;
+
+    Array possible_buttons {
+        Button { {}, m_close_bitmap.is_null() ? m_default_close_bitmap : m_close_bitmap },
+        Button { {}, m_maximize_bitmap.is_null() ? m_default_maximize_bitmap : m_maximize_bitmap },
+        Button { {}, m_minimize_bitmap.is_null() ? m_default_minimize_bitmap : m_minimize_bitmap }
+    };
+
+    auto buttons = possible_buttons.span().trim(button_count);
+
+    for (auto& button : buttons) {
+        pos -= window_button_width;
+        Gfx::IntRect button_rect { pos, 0, window_button_width, window_button_height };
+        button_rect.center_vertically_within(titlebar_text_rect);
+        button.rect = button_rect;
+    }
+
+    auto frame_rect = Gfx::WindowTheme::current().frame_rect_for_window(Gfx::WindowTheme::WindowType::Normal, rect, m_preview_palette, 0);
+
+    auto paint_shadow = [](Gfx::Painter& painter, Gfx::IntRect& frame_rect, Gfx::Bitmap const& shadow_bitmap) {
+        auto total_shadow_size = shadow_bitmap.height();
+        auto shadow_rect = frame_rect.inflated(total_shadow_size, total_shadow_size);
+        Gfx::StylePainter::paint_simple_rect_shadow(painter, shadow_rect, shadow_bitmap);
+    };
+
+    if ((state == Gfx::WindowTheme::WindowState::Active || state == Gfx::WindowTheme::WindowState::Highlighted) && m_active_window_shadow) {
+        paint_shadow(painter, frame_rect, *m_active_window_shadow);
+    } else if (state == Gfx::WindowTheme::WindowState::Inactive && m_inactive_window_shadow) {
+        paint_shadow(painter, frame_rect, *m_inactive_window_shadow);
+    }
+
+    Gfx::PainterStateSaver saver(painter);
+    painter.translate(frame_rect.location());
+    Gfx::WindowTheme::current().paint_normal_frame(painter, state, rect, title, icon, m_preview_palette, buttons.last().rect, 0, false);
+    painter.fill_rect(rect.translated(-frame_rect.location()), m_preview_palette.color(Gfx::ColorRole::Background));
+
+    for (auto& button : buttons) {
+        Gfx::StylePainter::paint_button(painter, button.rect, m_preview_palette, Gfx::ButtonStyle::Normal, false);
+        auto bitmap_rect = button.bitmap->rect().centered_within(button.rect);
+        painter.blit(bitmap_rect.location(), *button.bitmap, button.bitmap->rect());
+    }
+}
+
+void AbstractThemePreview::paint_event(GUI::PaintEvent& event)
+{
+    GUI::Frame::paint_event(event);
+    GUI::Painter painter(*this);
+
+    painter.add_clip_rect(event.rect());
+    painter.add_clip_rect(frame_inner_rect());
+
+    painter.fill_rect(frame_inner_rect(), m_preview_palette.desktop_background());
+    paint_preview(event);
+}
+
+}
diff --git a/Userland/Libraries/LibGUI/AbstractThemePreview.h b/Userland/Libraries/LibGUI/AbstractThemePreview.h
new file mode 100644
index 0000000000..1769cfba0b
--- /dev/null
+++ b/Userland/Libraries/LibGUI/AbstractThemePreview.h
@@ -0,0 +1,82 @@
+/*
+ * Copyright (c) 2020, Andreas Kling <kling@serenityos.org>
+ * Copyright (c) 2021, Sam Atkins <atkinssj@serenityos.org>
+ * Copyright (c) 2021, Antonio Di Stefano <tonio9681@gmail.com>
+ * Copyright (c) 2022, the SerenityOS developers.
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <LibGUI/Frame.h>
+#include <LibGfx/Bitmap.h>
+#include <LibGfx/Palette.h>
+#include <LibGfx/WindowTheme.h>
+
+namespace GUI {
+
+class AbstractThemePreview : public GUI::Frame {
+    C_OBJECT_ABSTRACT(AbstractThemePreview);
+
+public:
+    virtual ~AbstractThemePreview() override = default;
+
+    Gfx::Palette const& preview_palette() const { return m_preview_palette; }
+    void set_preview_palette(Gfx::Palette const&);
+    void set_theme_from_file(Core::File&);
+
+    void paint_window(StringView title, Gfx::IntRect const& rect, Gfx::WindowTheme::WindowState, Gfx::Bitmap const& icon, int button_count = 3);
+
+    Function<void(String const&)> on_theme_load_from_file;
+    Function<void()> on_palette_change;
+
+protected:
+    explicit AbstractThemePreview(Gfx::Palette const&);
+
+    inline Gfx::Bitmap const& active_window_icon() const
+    {
+        VERIFY(m_active_window_icon);
+        return *m_active_window_icon;
+    }
+    inline Gfx::Bitmap const& inactive_window_icon() const
+    {
+        VERIFY(m_inactive_window_icon);
+        return *m_inactive_window_icon;
+    }
+
+private:
+    virtual void paint_preview(GUI::PaintEvent&) = 0;
+
+    void load_theme_bitmaps();
+
+    virtual void paint_event(GUI::PaintEvent&) override;
+
+    Gfx::Palette m_preview_palette;
+
+    RefPtr<Gfx::Bitmap> m_active_window_icon;
+    RefPtr<Gfx::Bitmap> m_inactive_window_icon;
+
+    RefPtr<Gfx::Bitmap> m_default_close_bitmap;
+    RefPtr<Gfx::Bitmap> m_default_maximize_bitmap;
+    RefPtr<Gfx::Bitmap> m_default_minimize_bitmap;
+    RefPtr<Gfx::Bitmap> m_close_bitmap;
+    RefPtr<Gfx::Bitmap> m_maximize_bitmap;
+    RefPtr<Gfx::Bitmap> m_minimize_bitmap;
+    String m_last_close_path;
+    String m_last_maximize_path;
+    String m_last_minimize_path;
+
+    RefPtr<Gfx::Bitmap> m_active_window_shadow;
+    RefPtr<Gfx::Bitmap> m_inactive_window_shadow;
+    RefPtr<Gfx::Bitmap> m_menu_shadow;
+    RefPtr<Gfx::Bitmap> m_taskbar_shadow;
+    RefPtr<Gfx::Bitmap> m_tooltip_shadow;
+    String m_last_active_window_shadow_path;
+    String m_last_inactive_window_shadow_path;
+    String m_last_menu_shadow_path;
+    String m_last_taskbar_shadow_path;
+    String m_last_tooltip_shadow_path;
+};
+
+}
diff --git a/Userland/Libraries/LibGUI/CMakeLists.txt b/Userland/Libraries/LibGUI/CMakeLists.txt
index cc10cbfbd4..2ca3f61030 100644
--- a/Userland/Libraries/LibGUI/CMakeLists.txt
+++ b/Userland/Libraries/LibGUI/CMakeLists.txt
@@ -10,6 +10,7 @@ set(SOURCES
     AbstractTableView.cpp
     AbstractView.cpp
     AbstractZoomPanWidget.cpp
+    AbstractThemePreview.cpp
     Action.cpp
     ActionGroup.cpp
     Application.cpp
@@ -111,8 +112,8 @@ set(SOURCES
     VimEditingEngine.cpp
     Widget.cpp
     Window.cpp
-        ConnectionToWindowServer.cpp
-        ConnectionToWindowMangerServer.cpp
+    ConnectionToWindowServer.cpp
+    ConnectionToWindowMangerServer.cpp
     Wizards/WizardDialog.cpp
     Wizards/AbstractWizardPage.cpp
     Wizards/CoverWizardPage.cpp