Qt: Initial CPU debugger widget implementation

Co-Authored-By: liuk707 <62625900+liuk7071@users.noreply.github.com>

include/capstone.hpp

@@ -23,7 +23,7 @@ namespace Common {
 		// pc: program counter of the instruction to disassemble
 		// bytes: Byte representation of instruction
 		// buffer: text buffer to output the disassembly too
-		usize disassemble(std::string& buffer, u32 pc, std::span<u8> bytes, u64 offset = 0) {
+		usize disassemble(std::string& buffer, u32 pc, std::span<const u8> bytes, u64 offset = 0) {
 			if (!initialized) {
 				buffer = "Capstone was not properly initialized";
 				return 0;

include/emulator.hpp

@@ -122,14 +122,16 @@ class Emulator {
 	// Reloads some settings that require special handling, such as audio enable
 	void reloadSettings();
 
+	CPU& getCPU() { return cpu; }
+	Memory& getMemory() { return memory; }
+	Kernel& getKernel() { return kernel; }
+	Scheduler& getScheduler() { return scheduler; }
+
 	EmulatorConfig& getConfig() { return config; }
 	Cheats& getCheats() { return cheats; }
 	ServiceManager& getServiceManager() { return kernel.getServiceManager(); }
 	LuaManager& getLua() { return lua; }
-	Scheduler& getScheduler() { return scheduler; }
-	Memory& getMemory() { return memory; }
 	AudioDeviceInterface& getAudioDevice() { return audioDevice; }
-	Kernel& getKernel() { return kernel; }
 
 	RendererType getRendererType() const { return config.rendererType; }
 	Renderer* getRenderer() { return gpu.getRenderer(); }

include/panda_qt/cpu_debugger.hpp

@@ -0,0 +1,38 @@
+#pragma once
+#include <QListWidget>
+#include <QPlainTextEdit>
+#include <QScrollBar>
+#include <QWidget>
+
+#include "emulator.hpp"
+#include "panda_qt/disabled_widget_overlay.hpp"
+
+class CPUDebugger : public QWidget {
+	Q_OBJECT
+	Emulator* emu;
+
+	QListWidget* disasmListWidget;
+	QScrollBar* verticalScrollBar;
+	QPlainTextEdit* registerTextEdit;
+
+	DisabledWidgetOverlay* disabledOverlay;
+
+	bool enabled = false;
+
+  public:
+	CPUDebugger(Emulator* emulator, QWidget* parent = nullptr);
+	void enable();
+	void disable();
+
+  private:
+	// Update the state of the disassembler. Qt events should always call update, not updateDisasm/updateRegister
+	// As update properly handles thread safety
+	void update();
+	void updateDisasm();
+	void updateRegisters();
+
+	bool eventFilter(QObject* obj, QEvent* event) override;
+	void showEvent(QShowEvent* event) override;
+	void resizeEvent(QResizeEvent* event) override;
+	void keyPressEvent(QKeyEvent* event);
+};

include/panda_qt/disabled_widget_overlay.hpp

@@ -0,0 +1,28 @@
+#pragma once
+
+#include <QtWidgets>
+
+class DisabledWidgetOverlay : public QWidget {
+	Q_OBJECT
+
+  public:
+	DisabledWidgetOverlay(QWidget *parent = nullptr, QString overlayText = tr("This widget is disabled")) : text(overlayText), QWidget(parent) {
+		setVisible(false);
+	}
+
+  private:
+	QString text;
+
+	void paintEvent(QPaintEvent *) override {
+		QPainter painter = QPainter(this);
+		painter.fillRect(rect(), QColor(60, 60, 60, 128));
+		painter.setPen(Qt::gray);
+
+		QFont font = painter.font();
+		font.setBold(true);
+		font.setPointSize(18);
+
+		painter.setFont(font);
+		painter.drawText(rect(), Qt::AlignCenter, text);
+	}
+};

include/panda_qt/main_window.hpp

@@ -17,6 +17,7 @@
 #include "panda_qt/about_window.hpp"
 #include "panda_qt/cheats_window.hpp"
 #include "panda_qt/config_window.hpp"
+#include "panda_qt/cpu_debugger.hpp"
 #include "panda_qt/patch_window.hpp"
 #include "panda_qt/screen.hpp"
 #include "panda_qt/shader_editor.hpp"
@@ -110,6 +111,7 @@ class MainWindow : public QMainWindow {
 	TextEditorWindow* luaEditor;
 	PatchWindow* patchWindow;
 	ShaderEditorWindow* shaderEditor;
+	CPUDebugger* cpuDebugger;
 	ThreadDebugger* threadDebugger;
 
 	// We use SDL's game controller API since it's the sanest API that supports as many controllers as possible