TITANIC: In-progress converting message handling to be more like original

I currently was using multiple inheritance to define the message classes
that a class supports, but this caused problems when, for example, a
class tested to see if an object supported CMouseMsg. The class in
question supported several mouse messages, but a standard dynamic_cast
returned nullptr for the class, since it didn't directly support it

14 files changed, 104 insertions, 42 deletions

diff --git a/engines/titanic/core/background.cpp b/engines/titanic/core/background.cpp
index cb8e26450f..5859719026 100644
--- a/engines/titanic/core/background.cpp
+++ b/engines/titanic/core/background.cpp
@@ -24,6 +24,12 @@
 
 namespace Titanic {
 
+BEGIN_MESSAGE_MAP(CBackground, CGameObject)
+	ON_MESSAGE(StatusChangeMsg)
+	ON_MESSAGE(SetFrameMsg)
+	ON_MESSAGE(VisibleMsg)
+END_MESSAGE_MAP()
+
 CBackground::CBackground() : CGameObject(), _fieldBC(0), _fieldC0(0), _fieldDC(0) {
 }
 
@@ -49,7 +55,7 @@ void CBackground::load(SimpleFile *file) {
 	CGameObject::load(file);
 }
 
-bool CBackground::handleMessage(CStatusChangeMsg &msg) {
+bool CBackground::StatusChangeMsg(CStatusChangeMsg *msg) {
 	setVisible(true);
 	if (_fieldDC) {
 		fn1(_fieldBC, _fieldC0, 16);
@@ -59,13 +65,13 @@ bool CBackground::handleMessage(CStatusChangeMsg &msg) {
 	return true;
 }
 
-bool CBackground::handleMessage(CSetFrameMsg &msg) {
-	loadFrame(msg._frameNumber);
+bool CBackground::SetFrameMsg(CSetFrameMsg *msg) {
+	loadFrame(msg->_frameNumber);
 	return true;
 }
 
-bool CBackground::handleMessage(CVisibleMsg &msg) {
-	setVisible(msg._visible);
+bool CBackground::VisibleMsg(CVisibleMsg *msg) {
+	setVisible(msg->_visible);
 	return true;
 }
 
diff --git a/engines/titanic/core/background.h b/engines/titanic/core/background.h
index bd8f94987e..91c34073cd 100644
--- a/engines/titanic/core/background.h
+++ b/engines/titanic/core/background.h
@@ -28,10 +28,7 @@
 
 namespace Titanic {
 
-class CBackground : public CGameObject,
-	public CStatusChangeMsgTarget,
-	public CSetFrameMsgTarget,
-	public CVisibleMsgTarget {
+class CBackground : public CGameObject {
 protected:
 	int _fieldBC;
 	int _fieldC0;
@@ -39,9 +36,11 @@ protected:
 	CString _string2;
 	int _fieldDC;
 protected:
-	virtual bool handleMessage(CStatusChangeMsg &msg);
-	virtual bool handleMessage(CSetFrameMsg &msg);
-	virtual bool handleMessage(CVisibleMsg &msg);
+	DECLARE_MESSAGE_MAP
+
+	virtual bool StatusChangeMsg(CStatusChangeMsg *msg);
+	virtual bool SetFrameMsg(CSetFrameMsg *msg);
+	virtual bool VisibleMsg(CVisibleMsg *msg);
 public:
 	CLASSDEF
 	CBackground();
diff --git a/engines/titanic/core/game_object.cpp b/engines/titanic/core/game_object.cpp
index d2b1c29ed7..2bac988b31 100644
--- a/engines/titanic/core/game_object.cpp
+++ b/engines/titanic/core/game_object.cpp
@@ -31,6 +31,9 @@
 
 namespace Titanic {
 
+BEGIN_MESSAGE_MAP(CGameObject, CNamedItem)
+END_MESSAGE_MAP()
+
 void *CGameObject::_v1 = nullptr;
 
 CGameObject::CGameObject(): CNamedItem() {
diff --git a/engines/titanic/core/game_object.h b/engines/titanic/core/game_object.h
index 495fc8a2c9..7391a6b079 100644
--- a/engines/titanic/core/game_object.h
+++ b/engines/titanic/core/game_object.h
@@ -36,6 +36,7 @@ class CVideoSurface;
 class CMouseDragStartMsg;
 
 class CGameObject : public CNamedItem {
+	DECLARE_MESSAGE_MAP
 public:
 	static void *_v1;
 private:
diff --git a/engines/titanic/core/message_target.cpp b/engines/titanic/core/message_target.cpp
index a7dd3a02a2..b99fa5c606 100644
--- a/engines/titanic/core/message_target.cpp
+++ b/engines/titanic/core/message_target.cpp
@@ -23,7 +23,20 @@
 #include "titanic/core/message_target.h"
 
 namespace Titanic {
-	
+
+const MSGMAP *CMessageTarget::getMessageMap() const { 
+	return getThisMessageMap();
+}
+
+const MSGMAP *CMessageTarget::getThisMessageMap() {
+	static const MSGMAP_ENTRY _messageEntries[] = {
+		{ (PMSG)nullptr, nullptr }
+	};
+
+	static const MSGMAP messageMap = { nullptr, &_messageEntries[0] };
+	return &messageMap;
+}
+
 void CMessageTarget::save(SimpleFile *file, int indent) const {
 	file->writeNumberLine(0, indent);
 	CSaveableObject::save(file, indent);
diff --git a/engines/titanic/core/message_target.h b/engines/titanic/core/message_target.h
index b099546852..0f43bcd2c5 100644
--- a/engines/titanic/core/message_target.h
+++ b/engines/titanic/core/message_target.h
@@ -27,7 +27,49 @@
 
 namespace Titanic {
 
+class CMessageTarget;
+class CMessage;
+
+typedef bool (CMessageTarget::*PMSG)(CMessage *msg);
+
+struct MSGMAP_ENTRY {
+	PMSG _fn;
+	ClassDef *_class;
+};
+
+struct MSGMAP {
+	const MSGMAP *(* pFnGetBaseMap)();
+	const MSGMAP_ENTRY *lpEntries;
+};
+
+#define DECLARE_MESSAGE_MAP \
+protected: \
+	static const MSGMAP *getThisMessageMap(); \
+	virtual const MSGMAP *getMessageMap() const;
+
+#define BEGIN_MESSAGE_MAP(theClass, baseClass) \
+	const MSGMAP *theClass::getMessageMap() const \
+		{ return getThisMessageMap(); } \
+	const MSGMAP *theClass::getThisMessageMap() \
+	{ \
+		typedef theClass ThisClass;						   \
+		typedef baseClass TheBaseClass;					   \
+		typedef bool (theClass::*FNPTR)(CMessage *msg);    \
+		static const MSGMAP_ENTRY _messageEntries[] = {
+
+#define ON_MESSAGE(msgClass) \
+	{ static_cast<PMSG>((FNPTR)&ThisClass::msgClass), C##msgClass::_type },
+
+#define END_MESSAGE_MAP() \
+		{ (PMSG)nullptr, nullptr } \
+	}; \
+		static const MSGMAP messageMap = \
+		{ &TheBaseClass::getThisMessageMap, &_messageEntries[0] }; \
+		return &messageMap; \
+	}
+
 class CMessageTarget: public CSaveableObject {
+	DECLARE_MESSAGE_MAP
 public:
 	CLASSDEF
 
@@ -40,7 +82,6 @@ public:
 	 * Load the data for the class from file
 	 */
 	virtual void load(SimpleFile *file);
-
 };
 
 } // End of namespace Titanic
diff --git a/engines/titanic/core/named_item.cpp b/engines/titanic/core/named_item.cpp
index 02e75044aa..72d3fd9f42 100644
--- a/engines/titanic/core/named_item.cpp
+++ b/engines/titanic/core/named_item.cpp
@@ -27,6 +27,9 @@
 
 namespace Titanic {
 
+BEGIN_MESSAGE_MAP(CNamedItem, CTreeItem)
+END_MESSAGE_MAP()
+
 CString CNamedItem::dumpItem(int indent) const {
 	CString result = CTreeItem::dumpItem(indent);
 	result += " " + _name;
diff --git a/engines/titanic/core/named_item.h b/engines/titanic/core/named_item.h
index 6ee11e960e..9763e1b332 100644
--- a/engines/titanic/core/named_item.h
+++ b/engines/titanic/core/named_item.h
@@ -32,6 +32,7 @@ class CNodeItem;
 class CRoomItem;
 
 class CNamedItem: public CTreeItem {
+	DECLARE_MESSAGE_MAP
 public:
 	CString _name;
 public:
diff --git a/engines/titanic/core/tree_item.cpp b/engines/titanic/core/tree_item.cpp
index e7b61dc853..80eac81e99 100644
--- a/engines/titanic/core/tree_item.cpp
+++ b/engines/titanic/core/tree_item.cpp
@@ -36,6 +36,9 @@
 
 namespace Titanic {
 
+BEGIN_MESSAGE_MAP(CTreeItem, CMessageTarget)
+END_MESSAGE_MAP()
+
 CTreeItem::CTreeItem() : _parent(nullptr), _firstChild(nullptr),
 	_nextSibling(nullptr), _priorSibling(nullptr), _field14(0) {
 }
diff --git a/engines/titanic/core/tree_item.h b/engines/titanic/core/tree_item.h
index 9710a255d0..f5b1407fcd 100644
--- a/engines/titanic/core/tree_item.h
+++ b/engines/titanic/core/tree_item.h
@@ -36,6 +36,7 @@ class CScreenManager;
 class CRoomItem;
 
 class CTreeItem: public CMessageTarget {
+	DECLARE_MESSAGE_MAP
 private:
 	CTreeItem *_parent;
 	CTreeItem *_nextSibling;
diff --git a/engines/titanic/core/view_item.cpp b/engines/titanic/core/view_item.cpp
index 098adc0c61..26e0d86d27 100644
--- a/engines/titanic/core/view_item.cpp
+++ b/engines/titanic/core/view_item.cpp
@@ -30,6 +30,13 @@
 
 namespace Titanic {
 
+BEGIN_MESSAGE_MAP(CViewItem, CNamedItem)
+	ON_MESSAGE(MouseButtonDownMsg)
+	ON_MESSAGE(MouseButtonUpMsg)
+	ON_MESSAGE(MouseDoubleClickMsg)
+	ON_MESSAGE(MouseMoveMsg)
+END_MESSAGE_MAP()
+
 CViewItem::CViewItem() : CNamedItem() {
 	Common::fill(&_buttonUpTargets[0], &_buttonUpTargets[4], nullptr);
 	_field24 = 0;
@@ -161,7 +168,7 @@ void CViewItem::enterView(CViewItem *newView) {
 	}
 }
 
-bool CViewItem::handleMessage(CMouseButtonDownMsg &msg) {
+bool CViewItem::MouseButtonDownMsg(CMouseButtonDownMsg &msg) {
 	if (msg._buttons & MB_LEFT) {
 		if (!handleMouseMsg(&msg, true)) {
 			CGameManager *gm = getGameManager();
@@ -186,21 +193,21 @@ bool CViewItem::handleMessage(CMouseButtonDownMsg &msg) {
 	return true;
 }
 
-bool CViewItem::handleMessage(CMouseButtonUpMsg &msg) {
+bool CViewItem::MouseButtonUpMsg(CMouseButtonUpMsg &msg) {
 	if (msg._buttons & MB_LEFT)
 		handleMouseMsg(&msg, false);
 
 	return true;
 }
 
-bool CViewItem::handleMessage(CMouseDoubleClickMsg &msg) {
+bool CViewItem::MouseDoubleClickMsg(CMouseDoubleClickMsg &msg) {
 	if (msg._buttons & MB_LEFT)
 		handleMouseMsg(&msg, false);
 
 	return true;
 }
 
-bool CViewItem::handleMessage(CMouseMoveMsg &msg) {
+bool CViewItem::MouseMoveMsg(CMouseMoveMsg &msg) {
 	CScreenManager *screenManager = CScreenManager::_screenManagerPtr;
 
 	if (handleMouseMsg(&msg, true)) {
diff --git a/engines/titanic/core/view_item.h b/engines/titanic/core/view_item.h
index fc4089f924..f439929f5e 100644
--- a/engines/titanic/core/view_item.h
+++ b/engines/titanic/core/view_item.h
@@ -29,11 +29,8 @@
 
 namespace Titanic {
 
-class CViewItem : public CNamedItem,
-	public CMouseButtonDownMsgTarget,
-	public CMouseButtonUpMsgTarget,
-	public CMouseMoveMsgTarget,
-	public CMouseDoubleClickMsgTarget {
+class CViewItem : public CNamedItem {
+	DECLARE_MESSAGE_MAP
 private:
 	CTreeItem *_buttonUpTargets[4];
 private:
@@ -55,10 +52,10 @@ protected:
 	int _field50;
 	int _field54;
 protected:
-	virtual bool handleMessage(CMouseButtonDownMsg &msg);
-	virtual bool handleMessage(CMouseButtonUpMsg &msg);
-	virtual bool handleMessage(CMouseMoveMsg &msg);
-	virtual bool handleMessage(CMouseDoubleClickMsg &msg);
+	virtual bool MouseButtonDownMsg(CMouseButtonDownMsg &msg);
+	virtual bool MouseButtonUpMsg(CMouseButtonUpMsg &msg);
+	virtual bool MouseMoveMsg(CMouseMoveMsg &msg);
+	virtual bool MouseDoubleClickMsg(CMouseDoubleClickMsg &msg);
 public:
 	int _viewNumber;
 public:
diff --git a/engines/titanic/game/gondolier/gondolier_mixer.h b/engines/titanic/game/gondolier/gondolier_mixer.h
index c6ea840ea6..1186393d04 100644
--- a/engines/titanic/game/gondolier/gondolier_mixer.h
+++ b/engines/titanic/game/gondolier/gondolier_mixer.h
@@ -28,8 +28,7 @@
 
 namespace Titanic {
 
-class CGondolierMixer : public CGondolierBase, 
-	public CEnterRoomMsgTarget {
+class CGondolierMixer : public CGondolierBase {
 private:
 	int _fieldBC;
 	int _fieldC0;
diff --git a/engines/titanic/game/television.h b/engines/titanic/game/television.h
index c6c920b74c..9fb33943c0 100644
--- a/engines/titanic/game/television.h
+++ b/engines/titanic/game/television.h
@@ -29,19 +29,7 @@
 
 namespace Titanic {
 
-class CTelevision : public CBackground,
-	public CLeaveViewMsgTarget,
-	public CChangeSeasonMsgTarget,
-	public CEnterViewMsgTarget,
-	public CPETUpMsgTarget,
-	public CPETDownMsgTarget,
-	public CActMsgTarget,
-	public CPETActivateMsgTarget,
-	public CMovieEndMsgTarget,
-	public CShipSettingMsgTarget,
-	public CTurnOffTarget,
-	public CTurnOnTarget,
-	public CLightsMsgTarget {
+class CTelevision : public CBackground {
 private:
 	static int _v1;
 	static bool _turnOn;