/*	
 *		SceneIO.h - MAXScript-related scene file I/O (persistent globals, on-open script, etc.)
 *
 *			Copyright © Autodesk, Inc, 1998.  John Wainwright.
 *
 */

#ifndef _H_SCENEIO
#define _H_SCENEIO

class ValueLoader;

/* --------- Scene I/O chunk ID's ---------- */

#define OPENSCRIPT_CHUNK			0x0010    // obsoleted by CALLBACKSCRIPT_CHUNK
#define SAVESCRIPT_CHUNK			0x0020    // obsoleted by CALLBACKSCRIPT_CHUNK
#define PSGLOBALS_CHUNK				0x0030
#define MSPLUGINCLASS_CHUNK			0x0040
#define MSPLUGINCLASSHDR_CHUNK		0x0050
#define LENGTH_CHUNK				0x0060
#define CALLBACKSCRIPT_CHUNK		0x0070
#define CUSTATTRIBDEF_CHUNK			0x0080
#define SOURCE_CHUNK				0x00a0

/* ---- persistent global value loading ----- */

typedef Value* (*load_fn)(ILoad* iload, USHORT chunkID, ValueLoader* vl);

enum LoadableClassID 
{
	Undefined_Chunk = 0,	Boolean_Chunk,			Ok_Chunk,
	Integer_Chunk,			Float_Chunk,			String_Chunk, 
	Name_Chunk,				Array_Chunk,			Point3Value_Chunk, 
	QuatValue_Chunk,		RayValue_Chunk,			AngAxisValue_Chunk,
	EulerAnglesValue_Chunk, Matrix3Value_Chunk,		Point2Value_Chunk,
	ColorValue_Chunk,		MSTime_Chunk,			MSInterval_Chunk,
	MAXWrapper_Chunk,		Unsupplied_Chunk,		Struct_Chunk,
	Point4Value_Chunk,

	// add more here...

	HIGH_CLASS_CHUNK  // must be last
};

extern ScripterExport Value* load_value(ILoad* iload, ValueLoader* vload);
extern void save_persistent_callback_scripts(ISave* isave);
extern IOResult load_persistent_callback_script(ILoad* iload);
extern Tab<ValueLoader*> value_loaders;

#ifdef _DEBUG
  extern BOOL dump_load_postload_callback_order;
#endif

  // post global load callback scheme, allows different loaders to 
// permit ::Load() fns to register a callback to clean-up a load.  
// Eg, Array loader gets such a callback from MAXWrapper::Load() which
// uses this to build the MAXWrapper at post-load time, after object pointers
// have been back-patched.

// ::Load()'s that need to specialize this to provide a callback
class ValueLoadCallback
{
public:
	virtual Value* post_load() { return &undefined; }  // return the cleaned-up value
};

// each loader specializes this and gives it to the ::Load()
class ValueLoader
{
public:
	virtual void register_callback(ValueLoadCallback* cb) { }
	virtual void call_back() { }
};

// A post load callback to process persistent value load callbacks
class ValueLoadPLCB : public PostLoadCallback 
{
public:
	void proc(ILoad *iload)
	{
		for (int i = 0; i < value_loaders.Count(); i++)
			value_loaders[i]->call_back();
		value_loaders.ZeroCount();
		delete this;
#ifdef _DEBUG
		if (dump_load_postload_callback_order) 
			DebugPrint("MXS: PostLoadCallback run: ValueLoadPLCB\n");
#endif
	}
};

// callback script  (see MAXCallbacks.cpp)
class CallbackScript 
{ 
public:
	TSTR	script;		// callback script or script filename
	Value*  code;		// cached compiled code
	Value*  id;			// script ID
	short	flags;		// flags

	CallbackScript(TCHAR* iscript, Value* iid, short iflags)
	{
		script = iscript; code = NULL; id = iid; flags = iflags;
	}
};

#define MCB_SCRIPT_IS_FILE		0x0001
#define MCB_PERSISTENT			0x0002
#define MCB_HAS_ID				0x0004
#define MCB_INVALID				0x0008

extern Tab<CallbackScript*>* callback_scripts[];

#endif