LibVT: Allow updating the window progress via an escape sequence

You can now request an update of the terminal's window progress by
sending this escape sequence:

<esc>]9;<value>;<max_value>;<escape><backslash>

I'm sure we can find many interesting uses for this! :^)

Kernel/TTY/VirtualConsole.cpp

@@ -307,6 +307,11 @@ void VirtualConsole::set_window_title(const StringView&)
     // Do nothing.
 }
 
+void VirtualConsole::set_window_progress(int, int)
+{
+    // Do nothing.
+}
+
 void VirtualConsole::terminal_did_resize(u16 columns, u16 rows)
 {
     ASSERT(columns == 80);

Kernel/TTY/VirtualConsole.h

@@ -59,6 +59,7 @@ private:
     // ^TerminalClient
     virtual void beep() override;
     virtual void set_window_title(const StringView&) override;
+    virtual void set_window_progress(int, int) override;
     virtual void terminal_did_resize(u16 columns, u16 rows) override;
     virtual void terminal_history_changed() override;
     virtual void emit(const u8*, size_t) override;

Libraries/LibVT/Terminal.cpp

@@ -573,6 +573,9 @@ void Terminal::execute_xterm_command()
         // FIXME: Respect the provided ID
         m_current_attribute.href_id = String::format("%u", m_next_href_id++);
         break;
+    case 9:
+        m_client.set_window_progress(numeric_params[1], numeric_params[2]);
+        break;
     default:
         unimplemented_xterm_escape();
         break;

Libraries/LibVT/Terminal.h

@@ -42,6 +42,7 @@ public:
 
     virtual void beep() = 0;
     virtual void set_window_title(const StringView&) = 0;
+    virtual void set_window_progress(int value, int max) = 0;
     virtual void terminal_did_resize(u16 columns, u16 rows) = 0;
     virtual void terminal_history_changed() = 0;
     virtual void emit(const u8*, size_t) = 0;

Libraries/LibVT/TerminalWidget.cpp

@@ -47,6 +47,7 @@
 #include <LibGfx/Font.h>
 #include <LibGfx/Palette.h>
 #include <errno.h>
+#include <math.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -361,6 +362,14 @@ void TerminalWidget::paint_event(GUI::PaintEvent& event)
     }
 }
 
+void TerminalWidget::set_window_progress(int value, int max)
+{
+    float float_value = value;
+    float float_max = max;
+    float progress = (float_value / float_max) * 100.0f;
+    window()->set_progress((int)roundf(progress));
+}
+
 void TerminalWidget::set_window_title(const StringView& title)
 {
     if (!Utf8View(title).validate()) {

Libraries/LibVT/TerminalWidget.h

@@ -108,6 +108,7 @@ private:
     // ^TerminalClient
     virtual void beep() override;
     virtual void set_window_title(const StringView&) override;
+    virtual void set_window_progress(int value, int max) override;
     virtual void terminal_did_resize(u16 columns, u16 rows) override;
     virtual void terminal_history_changed() override;
     virtual void emit(const u8*, size_t) override;