Add API for monitors

CMakeLists.txt

@@ -52,6 +52,8 @@ target_sources(scratchcpp
     include/scratchcpp/rect.h
     include/scratchcpp/igraphicseffect.h
     include/scratchcpp/comment.h
+    include/scratchcpp/monitor.h
+    include/scratchcpp/imonitorhandler.h
 )
 
 add_library(zip SHARED

include/scratchcpp/block.h

@@ -27,15 +27,15 @@ class LIBSCRATCHCPP_EXPORT Block : public Entity
 
         void compile(Compiler *compiler);
 
-        std::string opcode() const;
+        const std::string &opcode() const;
 
         std::shared_ptr<Block> next() const;
-        std::string nextId() const;
+        const std::string &nextId() const;
         void setNext(std::shared_ptr<Block> block);
         void setNextId(const std::string &nextId);
 
         std::shared_ptr<Block> parent() const;
-        std::string parentId() const;
+        const std::string &parentId() const;
         void setParent(std::shared_ptr<Block> block);
         void setParentId(const std::string &id);
 
@@ -57,7 +57,7 @@ class LIBSCRATCHCPP_EXPORT Block : public Entity
         bool topLevel() const;
 
         std::shared_ptr<Comment> comment() const;
-        std::string commentId() const;
+        const std::string &commentId() const;
         void setComment(std::shared_ptr<Comment> comment);
         void setCommentId(const std::string &commentId);
 

include/scratchcpp/iengine.h

@@ -23,6 +23,8 @@ class List;
 class Script;
 class ITimer;
 class KeyEvent;
+class Monitor;
+class IMonitorHandler;
 
 /*!
  * \brief The IEngine interface provides an API for running Scratch projects.
@@ -84,6 +86,9 @@ class LIBSCRATCHCPP_EXPORT IEngine
         /*! Stops all currently playing sounds. */
         virtual void stopSounds() = 0;
 
+        /*! Updates the values of stage monitors. */
+        virtual void updateMonitors() = 0;
+
         /*! Steps all currently running threads. Use this to implement a custom event loop. */
         virtual void step() = 0;
 
@@ -300,6 +305,18 @@ class LIBSCRATCHCPP_EXPORT IEngine
         /*! Returns the Stage. */
         virtual Stage *stage() const = 0;
 
+        /*! Returns the list of monitors. */
+        virtual const std::vector<std::shared_ptr<Monitor>> &monitors() const = 0;
+
+        /*! Sets the list of monitors. */
+        virtual void setMonitors(const std::vector<std::shared_ptr<Monitor>> &newMonitors) = 0;
+
+        /*! Sets the function which is called when a monitor is added. */
+        virtual void setAddMonitorHandler(const std::function<void(Monitor *)> &handler) = 0;
+
+        /*! Sets the function which is called when a monitor is removed. */
+        virtual void setRemoveMonitorHandler(const std::function<void(Monitor *, IMonitorHandler *)> &handler) = 0;
+
         /*! Returns the list of extension names. */
         virtual const std::vector<std::string> &extensions() const = 0;
 

include/scratchcpp/imonitorhandler.h

@@ -0,0 +1,24 @@
+// SPDX-License-Identifier: Apache-2.0
+
+#pragma once
+
+#include "global.h"
+
+namespace libscratchcpp
+{
+
+class Monitor;
+class Value;
+
+class LIBSCRATCHCPP_EXPORT IMonitorHandler
+{
+    public:
+        virtual ~IMonitorHandler() { }
+
+        virtual void init(Monitor *) = 0;
+
+        virtual void onValueChanged(const VirtualMachine *vm) = 0;
+        virtual void onVisibleChanged(bool visible) = 0;
+};
+
+} // namespace libscratchcpp

include/scratchcpp/monitor.h

@@ -0,0 +1,84 @@
+// SPDX-License-Identifier: Apache-2.0
+
+#pragma once
+
+#include <scratchcpp/entity.h>
+
+#include <vector>
+
+namespace libscratchcpp
+{
+
+class IMonitorHandler;
+class Block;
+class Script;
+class Sprite;
+class Value;
+class Rect;
+class MonitorPrivate;
+
+/*! \brief The Monitor class represents a stage monitor. */
+class LIBSCRATCHCPP_EXPORT Monitor : public Entity
+{
+    public:
+        friend class Engine;
+
+        enum class Mode
+        {
+            Default,
+            Large,
+            Slider,
+            List
+        };
+
+        Monitor(const std::string &id, const std::string &opcode);
+        Monitor(const Monitor &) = delete;
+
+        void setInterface(IMonitorHandler *iface);
+
+        Mode mode() const;
+        void setMode(Mode mode);
+
+        std::shared_ptr<Block> block() const;
+
+        std::shared_ptr<Script> script() const;
+        void setScript(std::shared_ptr<Script> script);
+
+        Sprite *sprite() const;
+        void setSprite(Sprite *sprite);
+
+        const std::string &opcode() const;
+
+        void updateValue(const VirtualMachine *vm);
+
+        unsigned int width() const;
+        void setWidth(unsigned int width);
+
+        unsigned int height() const;
+        void setHeight(unsigned int height);
+
+        int x() const;
+        void setX(int x);
+
+        int y() const;
+        void setY(int y);
+
+        bool visible() const;
+        void setVisible(bool visible);
+
+        double sliderMin() const;
+        void setSliderMin(double sliderMin);
+
+        double sliderMax() const;
+        void setSliderMax(double sliderMax);
+
+        bool discrete() const;
+        void setDiscrete(bool discrete);
+
+        static Rect getInitialPosition(const std::vector<std::shared_ptr<Monitor>> &other, int monitorWidth, int monitorHeight);
+
+    private:
+        spimpl::unique_impl_ptr<MonitorPrivate> impl;
+};
+
+} // namespace libscratchcpp

include/scratchcpp/rect.h

@@ -32,6 +32,8 @@ class LIBSCRATCHCPP_EXPORT Rect
         double width() const;
         double height() const;
 
+        bool intersects(const Rect &rect) const;
+
     private:
         spimpl::impl_ptr<RectPrivate> impl;
 };