Tear out or duplicate what's unique for WindowServer from Widgets.

This turned into a huge refactoring that somehow also includes
making locks recursive/reentrant.

10 files changed, 5 insertions, 798 deletions

diff --git a/Widgets/AbstractScreen.cpp b/Widgets/AbstractScreen.cpp
deleted file mode 100644
index 10993e6363..0000000000
--- a/Widgets/AbstractScreen.cpp
+++ /dev/null
@@ -1,119 +0,0 @@
-#include "AbstractScreen.h"
-#include "EventLoop.h"
-#include "Event.h"
-#include "Widget.h"
-#include "WindowManager.h"
-#include <AK/Assertions.h>
-
-static AbstractScreen* s_the;
-
-void AbstractScreen::initialize()
-{
-    s_the = nullptr;
-}
-
-AbstractScreen& AbstractScreen::the()
-{
-    ASSERT(s_the);
-    return *s_the;
-}
-
-AbstractScreen::AbstractScreen(unsigned width, unsigned height)
-    : Object(nullptr)
-    , m_width(width)
-    , m_height(height)
-{
-    ASSERT(!s_the);
-    s_the = this;
-
-    m_cursor_location = rect().center();
-
-    Keyboard::the().set_client(this);
-}
-
-AbstractScreen::~AbstractScreen()
-{
-}
-
-void AbstractScreen::on_receive_mouse_data(int dx, int dy, bool left_button, bool right_button)
-{
-    auto prev_location = m_cursor_location;
-    m_cursor_location.moveBy(dx, dy);
-    m_cursor_location.constrain(rect());
-    if (m_cursor_location.x() >= width())
-        m_cursor_location.setX(width() - 1);
-    if (m_cursor_location.y() >= height())
-        m_cursor_location.setY(height() - 1);
-    if (m_cursor_location != prev_location) {
-        auto event = make<MouseEvent>(Event::MouseMove, m_cursor_location.x(), m_cursor_location.y());
-        EventLoop::main().postEvent(&WindowManager::the(), move(event));
-    }
-    bool prev_left_button = m_left_mouse_button_pressed;
-    bool prev_right_button = m_right_mouse_button_pressed;
-    m_left_mouse_button_pressed = left_button;
-    m_right_mouse_button_pressed = right_button;
-    if (prev_left_button != left_button) {
-        auto event = make<MouseEvent>(left_button ? Event::MouseDown : Event::MouseUp, m_cursor_location.x(), m_cursor_location.y(), MouseButton::Left);
-        EventLoop::main().postEvent(&WindowManager::the(), move(event));
-    }
-    if (prev_right_button != right_button) {
-        auto event = make<MouseEvent>(right_button ? Event::MouseDown : Event::MouseUp, m_cursor_location.x(), m_cursor_location.y(), MouseButton::Right);
-        EventLoop::main().postEvent(&WindowManager::the(), move(event));
-    }
-    if (m_cursor_location != prev_location || prev_left_button != left_button)
-        WindowManager::the().draw_cursor();
-}
-
-void AbstractScreen::on_key_pressed(Keyboard::Key key)
-{
-    auto event = make<KeyEvent>(Event::KeyDown, 0);
-    int key_code = 0;
-
-    switch (key.character) {
-    case 8: key_code = KeyboardKey::Backspace; break;
-    case 10: key_code = KeyboardKey::Return; break;
-    }
-    event->m_key = key_code;
-
-    if (key.character) {
-        char buf[] = { 0, 0 };
-        char& ch = buf[0];
-        ch = key.character;
-        if (key.shift()) {
-            if (ch >= 'a' && ch <= 'z') {
-                ch &= ~0x20;
-            } else {
-                switch (ch) {
-                case '1': ch = '!'; break;
-                case '2': ch = '@'; break;
-                case '3': ch = '#'; break;
-                case '4': ch = '$'; break;
-                case '5': ch = '%'; break;
-                case '6': ch = '^'; break;
-                case '7': ch = '&'; break;
-                case '8': ch = '*'; break;
-                case '9': ch = '('; break;
-                case '0': ch = ')'; break;
-                case '-': ch = '_'; break;
-                case '=': ch = '+'; break;
-                case '`': ch = '~'; break;
-                case ',': ch = '<'; break;
-                case '.': ch = '>'; break;
-                case '/': ch = '?'; break;
-                case '[': ch = '{'; break;
-                case ']': ch = '}'; break;
-                case '\\': ch = '|'; break;
-                case '\'': ch = '"'; break;
-                case ';': ch = ':'; break;
-                }
-            }
-        }
-        event->m_text = buf;
-    }
-
-    event->m_shift = key.shift();
-    event->m_ctrl = key.ctrl();
-    event->m_alt = key.alt();
-
-    EventLoop::main().postEvent(&WindowManager::the(), move(event));
-}
diff --git a/Widgets/AbstractScreen.h b/Widgets/AbstractScreen.h
deleted file mode 100644
index 444b1efcb3..0000000000
--- a/Widgets/AbstractScreen.h
+++ /dev/null
@@ -1,43 +0,0 @@
-#pragma once
-
-#include "Object.h"
-#include "Rect.h"
-#include "Size.h"
-#include "Keyboard.h"
-#include "PS2MouseDevice.h"
-
-class AbstractScreen : public Object, public KeyboardClient {
-public:
-    virtual ~AbstractScreen();
-
-    int width() const { return m_width; }
-    int height() const { return m_height; }
-
-    static AbstractScreen& the();
-
-    Size size() const { return { width(), height() }; }
-    Rect rect() const { return { 0, 0, width(), height() }; }
-
-    static void initialize();
-
-    Point cursor_location() const { return m_cursor_location; }
-    bool left_mouse_button_pressed() const { return m_left_mouse_button_pressed; }
-    bool right_mouse_button_pressed() const { return m_right_mouse_button_pressed; }
-
-    void on_receive_mouse_data(int dx, int dy, bool left_button, bool right_button);
-
-protected:
-    AbstractScreen(unsigned width, unsigned height);
-
-private:
-    // ^KeyboardClient
-    virtual void on_key_pressed(Keyboard::Key) final;
-
-    int m_width { 0 };
-    int m_height { 0 };
-
-    Point m_cursor_location;
-    bool m_left_mouse_button_pressed { false };
-    bool m_right_mouse_button_pressed { false };
-};
-
diff --git a/Widgets/FrameBuffer.cpp b/Widgets/FrameBuffer.cpp
deleted file mode 100644
index dc93460a07..0000000000
--- a/Widgets/FrameBuffer.cpp
+++ /dev/null
@@ -1,46 +0,0 @@
-#include "FrameBuffer.h"
-#include "GraphicsBitmap.h"
-#include <AK/Assertions.h>
-
-FrameBuffer* s_the;
-
-void FrameBuffer::initialize()
-{
-    s_the = nullptr;
-}
-
-FrameBuffer& FrameBuffer::the()
-{
-    ASSERT(s_the);
-    return *s_the;
-}
-
-FrameBuffer::FrameBuffer(unsigned width, unsigned height)
-    : AbstractScreen(width, height)
-{
-    ASSERT(!s_the);
-    s_the = this;
-}
-
-FrameBuffer::FrameBuffer(RGBA32* data, unsigned width, unsigned height)
-    : AbstractScreen(width, height)
-    , m_data(data)
-{
-    ASSERT(!s_the);
-    s_the = this;
-}
-
-
-FrameBuffer::~FrameBuffer()
-{
-}
-
-void FrameBuffer::show()
-{
-}
-
-RGBA32* FrameBuffer::scanline(int y)
-{
-    unsigned pitch = sizeof(RGBA32) * width();
-    return reinterpret_cast<RGBA32*>(((byte*)m_data) + (y * pitch));
-}
diff --git a/Widgets/FrameBuffer.h b/Widgets/FrameBuffer.h
deleted file mode 100644
index c0758f19a6..0000000000
--- a/Widgets/FrameBuffer.h
+++ /dev/null
@@ -1,25 +0,0 @@
-#pragma once
-
-#include "AbstractScreen.h"
-#include "Color.h"
-
-class GraphicsBitmap;
-
-class FrameBuffer final : public AbstractScreen {
-public:
-    FrameBuffer(unsigned width, unsigned height);
-    FrameBuffer(RGBA32*, unsigned width, unsigned height);
-    virtual ~FrameBuffer() override;
-
-    void show();
-
-    static FrameBuffer& the();
-
-    RGBA32* scanline(int y);
-
-    static void initialize();
-
-private:
-    RGBA32* m_data { nullptr };
-};
-
diff --git a/Widgets/GUIEventDevice.cpp b/Widgets/GUIEventDevice.cpp
deleted file mode 100644
index 20ba6c917b..0000000000
--- a/Widgets/GUIEventDevice.cpp
+++ /dev/null
@@ -1,38 +0,0 @@
-#include "GUIEventDevice.h"
-#include <Kernel/Process.h>
-#include <AK/Lock.h>
-#include <LibC/errno_numbers.h>
-
-//#define GUIEVENTDEVICE_DEBUG
-
-GUIEventDevice::GUIEventDevice()
-    : CharacterDevice(66, 1)
-{
-}
-
-GUIEventDevice::~GUIEventDevice()
-{
-}
-
-bool GUIEventDevice::can_read(Process& process) const
-{
-    return !process.gui_events().is_empty();
-}
-
-ssize_t GUIEventDevice::read(Process& process, byte* buffer, size_t size)
-{
-#ifdef GUIEVENTDEVICE_DEBUG
-    dbgprintf("GUIEventDevice::read(): %s<%u>, size=%u, sizeof(GUI_Event)=%u\n", process.name().characters(), process.pid(), size, sizeof(GUI_Event));
-#endif
-    if (process.gui_events().is_empty())
-        return 0;
-    LOCKER(process.gui_events_lock());
-    ASSERT(size == sizeof(GUI_Event));
-    *reinterpret_cast<GUI_Event*>(buffer) = process.gui_events().take_first();
-    return size;
-}
-
-ssize_t GUIEventDevice::write(Process&, const byte*, size_t)
-{
-    return -EINVAL;
-}
diff --git a/Widgets/GUIEventDevice.h b/Widgets/GUIEventDevice.h
deleted file mode 100644
index e98b208f05..0000000000
--- a/Widgets/GUIEventDevice.h
+++ /dev/null
@@ -1,16 +0,0 @@
-#pragma once
-
-#include <VirtualFileSystem/CharacterDevice.h>
-
-class GUIEventDevice final : public CharacterDevice {
-public:
-    GUIEventDevice();
-    virtual ~GUIEventDevice() override;
-
-private:
-    // ^CharacterDevice
-    virtual ssize_t read(Process&, byte* buffer, size_t bufferSize) override;
-    virtual ssize_t write(Process&, const byte* buffer, size_t bufferSize) override;
-    virtual bool can_read(Process&) const override;
-    virtual bool can_write(Process&) const override { return true; }
-};
diff --git a/Widgets/GraphicsBitmap.cpp b/Widgets/GraphicsBitmap.cpp
index 6fc98447f9..3dbc47cf47 100644
--- a/Widgets/GraphicsBitmap.cpp
+++ b/Widgets/GraphicsBitmap.cpp
@@ -1,10 +1,10 @@
 #include "GraphicsBitmap.h"
-#include "EventLoop.h"
 #include <AK/kmalloc.h>
 
 #ifdef KERNEL
-#include "Process.h"
-#include "MemoryManager.h"
+#include <Kernel/Process.h>
+#include <Kernel/MemoryManager.h>
+#include <WindowServer/WSEventLoop.h>
 #endif
 
 #ifdef KERNEL
@@ -24,7 +24,7 @@ GraphicsBitmap::GraphicsBitmap(Process& process, const Size& size)
     m_client_region->commit(process);
 
     {
-        auto& server = EventLoop::main().server_process();
+        auto& server = WSEventLoop::the().server_process();
         ProcessInspectionHandle composer_handle(server);
         m_server_region = server.allocate_region_with_vmo(LinearAddress(), size_in_bytes, move(vmo), 0, "GraphicsBitmap (shared)", true, true);
     }
@@ -50,7 +50,7 @@ GraphicsBitmap::~GraphicsBitmap()
     if (m_client_region)
         m_client_process->deallocate_region(*m_client_region);
     if (m_server_region)
-        EventLoop::main().server_process().deallocate_region(*m_server_region);
+        WSEventLoop::the().server_process().deallocate_region(*m_server_region);
 #endif
     m_data = nullptr;
 }
diff --git a/Widgets/Window.h b/Widgets/Window.h
index 3da05c3c97..1bbe354eb1 100644
--- a/Widgets/Window.h
+++ b/Widgets/Window.h
@@ -28,7 +28,6 @@ public:
     void set_rect_without_repaint(const Rect& rect) { m_rect = rect; }
 
     Point position() const { return m_rect.location(); }
-    void set_position(const Point& position) { set_rect({ position.x(), position.y(), width(), height() }); }
     void set_position_without_repaint(const Point& position) { set_rect_without_repaint({ position.x(), position.y(), width(), height() }); }
 
     virtual void event(Event&) override;
diff --git a/Widgets/WindowManager.cpp b/Widgets/WindowManager.cpp
deleted file mode 100644
index 2b77912277..0000000000
--- a/Widgets/WindowManager.cpp
+++ /dev/null
@@ -1,409 +0,0 @@
-#include "WindowManager.h"
-#include "Painter.h"
-#include "Widget.h"
-#include "Window.h"
-#include "AbstractScreen.h"
-#include "EventLoop.h"
-#include "FrameBuffer.h"
-#include "Process.h"
-#include "MemoryManager.h"
-
-//#define DEBUG_FLUSH_YELLOW
-
-static const int windowTitleBarHeight = 16;
-
-static inline Rect titleBarRectForWindow(const Rect& window)
-{
-    return {
-        window.x() - 1,
-        window.y() - windowTitleBarHeight,
-        window.width() + 2,
-        windowTitleBarHeight
-    };
-}
-
-static inline Rect titleBarTitleRectForWindow(const Rect& window)
-{
-    auto titleBarRect = titleBarRectForWindow(window);
-    return {
-        titleBarRect.x() + 2,
-        titleBarRect.y(),
-        titleBarRect.width() - 4,
-        titleBarRect.height()
-    };
-}
-
-static inline Rect borderRectForWindow(const Rect& window)
-{
-    auto titleBarRect = titleBarRectForWindow(window);
-    return { titleBarRect.x() - 1,
-        titleBarRect.y() - 1,
-        titleBarRect.width() + 2,
-        windowTitleBarHeight + window.height() + 3
-    };
-}
-
-static inline Rect outerRectForWindow(const Rect& window)
-{
-    auto rect = borderRectForWindow(window);
-    rect.inflate(2, 2);
-    return rect;
-}
-
-static WindowManager* s_the_window_manager;
-
-WindowManager& WindowManager::the()
-{
-    if (!s_the_window_manager)
-        s_the_window_manager = new WindowManager;
-    return *s_the_window_manager;
-}
-
-void WindowManager::initialize()
-{
-    s_the_window_manager = nullptr;
-}
-
-static const char* cursor_bitmap_inner_ascii = {
-    " #          "
-    " ##         "
-    " ###        "
-    " ####       "
-    " #####      "
-    " ######     "
-    " #######    "
-    " ########   "
-    " #########  "
-    " ########## "
-    " ######     "
-    " ##  ##     "
-    " #    ##    "
-    "      ##    "
-    "       ##   "
-    "       ##   "
-    "            "
-};
-
-static const char* cursor_bitmap_outer_ascii = {
-    "##          "
-    "# #         "
-    "#  #        "
-    "#   #       "
-    "#    #      "
-    "#     #     "
-    "#      #    "
-    "#       #   "
-    "#        #  "
-    "#         # "
-    "#      #### "
-    "#  ##  #    "
-    "# #  #  #   "
-    "##   #  #   "
-    "      #  #  "
-    "      #  #  "
-    "       ##   "
-};
-
-WindowManager::WindowManager()
-    : m_framebuffer(FrameBuffer::the())
-    , m_screen_rect(m_framebuffer.rect())
-{
-    auto size = m_screen_rect.size();
-    m_front_bitmap = GraphicsBitmap::create_wrapper(size, m_framebuffer.scanline(0));
-    auto* region = current->allocate_region(LinearAddress(), size.width() * size.height() * sizeof(RGBA32), "BackBitmap", true, true, true);
-    m_back_bitmap = GraphicsBitmap::create_wrapper(m_screen_rect.size(), (RGBA32*)region->linearAddress.get());
-
-    m_front_painter = make<Painter>(*m_front_bitmap);
-    m_back_painter = make<Painter>(*m_back_bitmap);
-
-    m_activeWindowBorderColor = Color(0, 64, 192);
-    m_activeWindowTitleColor = Color::White;
-
-    m_inactiveWindowBorderColor = Color(64, 64, 64);
-    m_inactiveWindowTitleColor = Color::White;
-
-    m_cursor_bitmap_inner = CharacterBitmap::createFromASCII(cursor_bitmap_inner_ascii, 12, 17);
-    m_cursor_bitmap_outer = CharacterBitmap::createFromASCII(cursor_bitmap_outer_ascii, 12, 17);
-
-    invalidate();
-    compose();
-}
-
-WindowManager::~WindowManager()
-{
-}
-
-void WindowManager::paintWindowFrame(Window& window)
-{
-    //printf("[WM] paintWindowFrame {%p}, rect: %d,%d %dx%d\n", &window, window.rect().x(), window.rect().y(), window.rect().width(), window.rect().height());
-
-    auto titleBarRect = titleBarRectForWindow(window.rect());
-    auto titleBarTitleRect = titleBarTitleRectForWindow(window.rect());
-    auto outerRect = outerRectForWindow(window.rect());
-    auto borderRect = borderRectForWindow(window.rect());
-
-    Rect inner_border_rect {
-        window.x() - 1,
-        window.y() - 1,
-        window.width() + 2,
-        window.height() + 2
-    };
-
-    auto titleColor = &window == activeWindow() ? m_activeWindowTitleColor : m_inactiveWindowTitleColor;
-    auto borderColor = &window == activeWindow() ? m_activeWindowBorderColor : m_inactiveWindowBorderColor;
-
-    m_back_painter->draw_rect(borderRect, Color::MidGray);
-    m_back_painter->draw_rect(outerRect, borderColor);
-    m_back_painter->fill_rect(titleBarRect, borderColor);
-    m_back_painter->draw_rect(inner_border_rect, borderColor);
-    m_back_painter->draw_text(titleBarTitleRect, window.title(), Painter::TextAlignment::CenterLeft, titleColor);
-}
-
-void WindowManager::addWindow(Window& window)
-{
-    m_windows.set(&window);
-    m_windows_in_order.append(&window);
-    if (!activeWindow())
-        setActiveWindow(&window);
-}
-
-void WindowManager::move_to_front(Window& window)
-{
-    m_windows_in_order.remove(&window);
-    m_windows_in_order.append(&window);
-}
-
-void WindowManager::did_paint(Window& window)
-{
-    invalidate(window);
-}
-
-void WindowManager::removeWindow(Window& window)
-{
-    if (!m_windows.contains(&window))
-        return;
-
-    invalidate(window);
-    m_windows.remove(&window);
-    m_windows_in_order.remove(&window);
-    if (!activeWindow() && !m_windows.is_empty())
-        setActiveWindow(*m_windows.begin());
-}
-
-void WindowManager::notifyTitleChanged(Window& window)
-{
-    printf("[WM] Window{%p} title set to '%s'\n", &window, window.title().characters());
-}
-
-void WindowManager::notifyRectChanged(Window& window, const Rect& old_rect, const Rect& new_rect)
-{
-    printf("[WM] Window %p rect changed (%d,%d %dx%d) -> (%d,%d %dx%d)\n", &window, old_rect.x(), old_rect.y(), old_rect.width(), old_rect.height(), new_rect.x(), new_rect.y(), new_rect.width(), new_rect.height());
-    invalidate(outerRectForWindow(old_rect));
-    invalidate(outerRectForWindow(new_rect));
-}
-
-void WindowManager::handleTitleBarMouseEvent(Window& window, MouseEvent& event)
-{
-    if (event.type() == Event::MouseDown && event.button() == MouseButton::Left) {
-        printf("[WM] Begin dragging Window{%p}\n", &window);
-        m_dragWindow = window.makeWeakPtr();;
-        m_dragOrigin = event.position();
-        m_dragWindowOrigin = window.position();
-        m_dragStartRect = outerRectForWindow(window.rect());
-        window.set_is_being_dragged(true);
-        return;
-    }
-}
-
-void WindowManager::processMouseEvent(MouseEvent& event)
-{
-    if (event.type() == Event::MouseUp && event.button() == MouseButton::Left) {
-        if (m_dragWindow) {
-            printf("[WM] Finish dragging Window{%p}\n", m_dragWindow.ptr());
-            invalidate(m_dragStartRect);
-            invalidate(*m_dragWindow);
-            m_dragWindow->set_is_being_dragged(false);
-            m_dragEndRect = outerRectForWindow(m_dragWindow->rect());
-            m_dragWindow = nullptr;
-            return;
-        }
-    }
-
-    if (event.type() == Event::MouseMove) {
-        if (m_dragWindow) {
-            auto old_window_rect = m_dragWindow->rect();
-            Point pos = m_dragWindowOrigin;
-            printf("[WM] Dragging [origin: %d,%d] now: %d,%d\n", m_dragOrigin.x(), m_dragOrigin.y(), event.x(), event.y());
-            pos.moveBy(event.x() - m_dragOrigin.x(), event.y() - m_dragOrigin.y());
-            m_dragWindow->set_position_without_repaint(pos);
-            invalidate(outerRectForWindow(old_window_rect));
-            invalidate(outerRectForWindow(m_dragWindow->rect()));
-            return;
-        }
-    }
-
-    for (auto* window = m_windows_in_order.tail(); window; window = window->prev()) {
-        if (titleBarRectForWindow(window->rect()).contains(event.position())) {
-            if (event.type() == Event::MouseDown) {
-                move_to_front(*window);
-                setActiveWindow(window);
-            }
-            handleTitleBarMouseEvent(*window, event);
-            return;
-        }
-
-        if (window->rect().contains(event.position())) {
-            if (event.type() == Event::MouseDown) {
-                move_to_front(*window);
-                setActiveWindow(window);
-            }
-            // FIXME: Re-use the existing event instead of crafting a new one?
-            auto localEvent = make<MouseEvent>(event.type(), event.x() - window->rect().x(), event.y() - window->rect().y(), event.button());
-            window->event(*localEvent);
-            return;
-        }
-    }
-}
-
-void WindowManager::compose()
-{
-    auto invalidated_rects = move(m_invalidated_rects);
-    printf("[WM] compose #%u (%u rects)\n", ++m_recompose_count, invalidated_rects.size());
-
-    dbgprintf("kmalloc stats: alloc:%u free:%u eternal:%u\n", sum_alloc, sum_free, kmalloc_sum_eternal);
-
-    auto any_window_contains_rect = [this] (const Rect& r) {
-        for (auto* window = m_windows_in_order.head(); window; window = window->next()) {
-            if (outerRectForWindow(window->rect()).contains(r))
-                return true;
-        }
-        return false;
-    };
-
-    for (auto& r : invalidated_rects) {
-        if (any_window_contains_rect(r))
-            continue;
-        //dbgprintf("Repaint root %d,%d %dx%d\n", r.x(), r.y(), r.width(), r.height());
-        m_back_painter->fill_rect(r, Color(0, 72, 96));
-    }
-    for (auto* window = m_windows_in_order.head(); window; window = window->next()) {
-        if (!window->backing())
-            continue;
-        paintWindowFrame(*window);
-        m_back_painter->blit(window->position(), *window->backing());
-    }
-    for (auto& r : invalidated_rects)
-        flush(r);
-    draw_cursor();
-}
-
-void WindowManager::draw_cursor()
-{
-    auto cursor_location = m_framebuffer.cursor_location();
-    Rect cursor_rect { cursor_location.x(), cursor_location.y(), (int)m_cursor_bitmap_inner->width(), (int)m_cursor_bitmap_inner->height() };
-    flush(m_last_cursor_rect.united(cursor_rect));
-    Color inner_color = Color::White;
-    Color outer_color = Color::Black;
-    if (m_framebuffer.left_mouse_button_pressed())
-        swap(inner_color, outer_color);
-    m_front_painter->draw_bitmap(cursor_location, *m_cursor_bitmap_inner, inner_color);
-    m_front_painter->draw_bitmap(cursor_location, *m_cursor_bitmap_outer, outer_color);
-    m_last_cursor_rect = cursor_rect;
-}
-
-void WindowManager::event(Event& event)
-{
-    if (event.isMouseEvent())
-        return processMouseEvent(static_cast<MouseEvent&>(event));
-
-    if (event.isKeyEvent()) {
-        // FIXME: This is a good place to hook key events globally. :)
-        if (m_activeWindow)
-            return m_activeWindow->event(event);
-        return Object::event(event);
-    }
-
-    if (event.type() == Event::WM_Compose) {
-        m_pending_compose_event = false;
-        compose();
-        return;
-    }
-
-    return Object::event(event);
-}
-
-void WindowManager::setActiveWindow(Window* window)
-{
-    if (window == m_activeWindow.ptr())
-        return;
-
-    if (auto* previously_active_window = m_activeWindow.ptr()) {
-        invalidate(*previously_active_window);
-        EventLoop::main().postEvent(previously_active_window, make<Event>(Event::WindowBecameInactive));
-    }
-    m_activeWindow = window->makeWeakPtr();
-    if (m_activeWindow) {
-        invalidate(*m_activeWindow);
-        EventLoop::main().postEvent(m_activeWindow.ptr(), make<Event>(Event::WindowBecameActive));
-    }
-}
-
-bool WindowManager::isVisible(Window& window) const
-{
-    return m_windows.contains(&window);
-}
-
-void WindowManager::invalidate()
-{
-    m_invalidated_rects.clear_with_capacity();
-    m_invalidated_rects.append(m_screen_rect);
-}
-
-void WindowManager::invalidate(const Rect& a_rect)
-{
-    auto rect = Rect::intersection(a_rect, m_screen_rect);
-    if (rect.is_empty())
-        return;
-
-    for (auto& r : m_invalidated_rects) {
-        if (r.contains(rect))
-            return;
-        if (r.intersects(rect)) {
-            // Unite with the existing dirty rect.
-            // FIXME: It would be much nicer to compute the exact rects needing repaint.
-            r = r.united(rect);
-            return;
-        }
-    }
-
-    m_invalidated_rects.append(rect);
-
-    if (!m_pending_compose_event) {
-        EventLoop::main().postEvent(this, make<Event>(Event::WM_Compose));
-        m_pending_compose_event = true;
-    }
-}
-
-void WindowManager::invalidate(const Window& window)
-{
-    invalidate(outerRectForWindow(window.rect()));
-}
-
-void WindowManager::flush(const Rect& a_rect)
-{
-    auto rect = Rect::intersection(a_rect, m_screen_rect);
-
-    RGBA32* front_ptr = m_front_bitmap->scanline(rect.y()) + rect.x();
-    const RGBA32* back_ptr = m_back_bitmap->scanline(rect.y()) + rect.x();
-    size_t pitch = m_back_bitmap->pitch();
-
-#ifdef DEBUG_FLUSH_YELLOW
-    m_front_painter->fill_rect(rect, Color::Yellow);
-#endif
-
-    for (int y = 0; y < rect.height(); ++y) {
-        fast_dword_copy(front_ptr, back_ptr, rect.width());
-        front_ptr = (RGBA32*)((byte*)front_ptr + pitch);
-        back_ptr = (const RGBA32*)((const byte*)back_ptr + pitch);
-    }
-}
diff --git a/Widgets/WindowManager.h b/Widgets/WindowManager.h
deleted file mode 100644
index a5277861f4..0000000000
--- a/Widgets/WindowManager.h
+++ /dev/null
@@ -1,96 +0,0 @@
-#pragma once
-
-#include "Object.h"
-#include "Rect.h"
-#include "Color.h"
-#include "Painter.h"
-#include <AK/HashTable.h>
-#include <AK/InlineLinkedList.h>
-#include <AK/WeakPtr.h>
-
-class FrameBuffer;
-class MouseEvent;
-class PaintEvent;
-class Widget;
-class Window;
-class CharacterBitmap;
-class GraphicsBitmap;
-
-class WindowManager : public Object {
-public:
-    static WindowManager& the(); 
-    void addWindow(Window&);
-    void removeWindow(Window&);
-
-    void notifyTitleChanged(Window&);
-    void notifyRectChanged(Window&, const Rect& oldRect, const Rect& newRect);
-
-    Window* activeWindow() { return m_activeWindow.ptr(); }
-    void setActiveWindow(Window*);
-
-    bool isVisible(Window&) const;
-
-    void did_paint(Window&);
-
-    void move_to_front(Window&);
-
-    static void initialize();
-
-    void draw_cursor();
-
-    void invalidate(const Window&);
-    void invalidate(const Rect&);
-    void invalidate();
-    void flush(const Rect&);
-
-private:
-    WindowManager();
-    virtual ~WindowManager() override;
-
-    void processMouseEvent(MouseEvent&);
-    void handleTitleBarMouseEvent(Window&, MouseEvent&);
-    
-    virtual void event(Event&) override;
-
-    void compose();
-    void paintWindowFrame(Window&);
-
-    FrameBuffer& m_framebuffer;
-    Rect m_screen_rect;
-
-    Color m_activeWindowBorderColor;
-    Color m_activeWindowTitleColor;
-
-    Color m_inactiveWindowBorderColor;
-    Color m_inactiveWindowTitleColor;
-
-    HashTable<Window*> m_windows;
-    InlineLinkedList<Window> m_windows_in_order;
-
-    WeakPtr<Window> m_activeWindow;
-
-    WeakPtr<Window> m_dragWindow;
-
-    Point m_dragOrigin;
-    Point m_dragWindowOrigin;
-    Rect m_lastDragRect;
-    Rect m_dragStartRect;
-    Rect m_dragEndRect;
-
-    Rect m_last_cursor_rect;
-
-    unsigned m_recompose_count { 0 };
-
-    RetainPtr<GraphicsBitmap> m_front_bitmap;
-    RetainPtr<GraphicsBitmap> m_back_bitmap;
-
-    Vector<Rect> m_invalidated_rects;
-
-    bool m_pending_compose_event { false };
-
-    RetainPtr<CharacterBitmap> m_cursor_bitmap_inner;
-    RetainPtr<CharacterBitmap> m_cursor_bitmap_outer;
-
-    OwnPtr<Painter> m_back_painter;
-    OwnPtr<Painter> m_front_painter;
-};