/***************************************************************************

    state.h

    Save state management functions.

****************************************************************************

    Copyright Aaron Giles
    All rights reserved.

    Redistribution and use in source and binary forms, with or without
    modification, are permitted provided that the following conditions are
    met:

        * Redistributions of source code must retain the above copyright
          notice, this list of conditions and the following disclaimer.
        * Redistributions in binary form must reproduce the above copyright
          notice, this list of conditions and the following disclaimer in
          the documentation and/or other materials provided with the
          distribution.
        * Neither the name 'MAME' nor the names of its contributors may be
          used to endorse or promote products derived from this software
          without specific prior written permission.

    THIS SOFTWARE IS PROVIDED BY AARON GILES ''AS IS'' AND ANY EXPRESS OR
    IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
    WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
    DISCLAIMED. IN NO EVENT SHALL AARON GILES BE LIABLE FOR ANY DIRECT,
    INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
    (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
    SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
    HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
    STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
    IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
    POSSIBILITY OF SUCH DAMAGE.

***************************************************************************/

#pragma once

#ifndef __EMU_H__
#error Dont include this file directly; include emu.h instead.
#endif

#ifndef __STATE_H__
#define __STATE_H__



//**************************************************************************
//  CONSTANTS
//**************************************************************************

enum state_save_error
{
	STATERR_NONE,
	STATERR_ILLEGAL_REGISTRATIONS,
	STATERR_INVALID_HEADER,
	STATERR_READ_ERROR,
	STATERR_WRITE_ERROR
};



//**************************************************************************
//  MACROS
//**************************************************************************

// macros to declare presave/postload functions with the appropriate parameters
#define STATE_PRESAVE(name) void name(running_machine &machine, void *param)
#define STATE_POSTLOAD(name) void name(running_machine &machine, void *param)


// templates to assume the 'param' of a presave/postload function is a class pointer
template<class T, void (T::*func)()>
void state_presave_stub(running_machine &machine, void *param)
{
	T *target = reinterpret_cast<T *>(param);
	(target->*func)();
}

template<class T, void (T::*func)()>
void state_postload_stub(running_machine &machine, void *param)
{
	T *target = reinterpret_cast<T *>(param);
	(target->*func)();
}


// use this to declare a given type is a simple, non-pointer type that can be
// saved; in general, this is intended only to be used for specific enum types
// defined by your device
#define ALLOW_SAVE_TYPE(TYPE) template<> struct state_manager::type_checker<TYPE> { static const bool is_atom = true; static const bool is_pointer = false; }



// register items with explicit tags
#define state_save_register_item(_mach, _mod, _tag, _index, _val) \
	(_mach).state().save_item(_mod, _tag, _index, _val, #_val)

#define state_save_register_item_pointer(_mach, _mod, _tag, _index, _val, _count) \
	(_mach).state().save_pointer(_mod, _tag, _index, _val, #_val, _count)

#define state_save_register_item_array(_mach, _mod, _tag, _index, _val) \
	(_mach).state().save_item(_mod, _tag, _index, _val, #_val)

#define state_save_register_item_2d_array(_mach, _mod, _tag, _index, _val) \
	(_mach).state().save_item(_mod, _tag, _index, _val, #_val)

#define state_save_register_item_bitmap(_mach, _mod, _tag, _index, _val) \
	(_mach).state().save_item(_mod, _tag, _index, *(_val), #_val)



// register global items
#define state_save_register_global(_mach, _val) \
	(_mach).state().save_item(_val, #_val)

#define state_save_register_global_pointer(_mach, _val, _count) \
	(_mach).state().save_pointer(_val, #_val, _count)

#define state_save_register_global_array(_mach, _val) \
	(_mach).state().save_item(_val, #_val)

#define state_save_register_global_2d_array(_mach, _val) \
	(_mach).state().save_item(_val, #_val)

#define state_save_register_global_bitmap(_mach, _val) \
	(_mach).state().save_item(*(_val), #_val)



//**************************************************************************
//  TYPE DEFINITIONS
//**************************************************************************

class state_manager
{
	// type_checker is a set of templates to identify valid save types
	template<typename T> struct type_checker { static const bool is_atom = false; static const bool is_pointer = false; };
	template<typename T> struct type_checker<T*> { static const bool is_atom = false; static const bool is_pointer = true; };

public:
	typedef void (*prepost_func)(running_machine &machine, void *param);

	// construction/destruction
	state_manager(running_machine &machine);

	// getters
	int registration_count() const { return m_entry_list.count(); }
	bool registration_allowed() const { return m_reg_allowed; }

	// registration control
	void allow_registration(bool allowed = true);
	const char *indexed_item(int index, void *&base, UINT32 &valsize, UINT32 &valcount) const;

	// function registration
	void register_presave(prepost_func func, void *param);
	void register_postload(prepost_func func, void *param);

	// generic memory registration
	void save_memory(const char *module, const char *tag, UINT32 index, const char *name, void *val, UINT32 valsize, UINT32 valcount = 1);

	// templatized wrapper for general objects
	template<typename T>
	void save_item(const char *module, const char *tag, int index, T &value, const char *valname)
	{
		if (type_checker<T>::is_pointer) throw emu_fatalerror("Called save_item on a pointer with no count!");
		if (!type_checker<T>::is_atom) throw emu_fatalerror("Called save_item on a non-fundamental type!");
		save_memory(module, tag, index, valname, &value, sizeof(value));
	}

	// templatized wrapper for 1-dimensional arrays
	template<typename T, std::size_t N>
	void save_item(const char *module, const char *tag, int index, T (&value)[N], const char *valname)
	{
		if (!type_checker<T>::is_atom) throw emu_fatalerror("Called save_item on a non-fundamental type!");
		save_memory(module, tag, index, valname, &value[0], sizeof(value[0]), N);
	}

	// templatized wrapper for 2-dimensional arrays
	template<typename T, std::size_t M, std::size_t N>
	void save_item(const char *module, const char *tag, int index, T (&value)[M][N], const char *valname)
	{
		if (!type_checker<T>::is_atom) throw emu_fatalerror("Called save_item on a non-fundamental type!");
		save_memory(module, tag, index, valname, &value[0][0], sizeof(value[0][0]), M * N);
	}

	// templatized wrapper for pointers
	template<typename T>
	void save_pointer(const char *module, const char *tag, int index, T *value, const char *valname, UINT32 count)
	{
		if (!type_checker<T>::is_atom) throw emu_fatalerror("Called save_item on a non-fundamental type!");
		save_memory(module, tag, index, valname, value, sizeof(*value), count);
	}

	// global memory registration
	template<typename T>
	void save_item(T &value, const char *valname, int index = 0) { save_item("global", NULL, index, value, valname); }
	template<typename T>
	void save_pointer(T *value, const char *valname, UINT32 count, int index = 0) { save_pointer("global", NULL, index, value, valname, count); }

	// file processing
	static state_save_error check_file(running_machine &machine, emu_file &file, const char *gamename, void (CLIB_DECL *errormsg)(const char *fmt, ...));
	state_save_error write_file(emu_file &file);
	state_save_error read_file(emu_file &file);

private:
	// internal helpers
	UINT32 signature() const;
	void dump_registry() const;
	static state_save_error validate_header(const UINT8 *header, const char *gamename, UINT32 signature, void (CLIB_DECL *errormsg)(const char *fmt, ...), const char *error_prefix);

	// state callback item
	class state_callback
	{
	public:
		// construction/destruction
		state_callback(prepost_func callback, void *param);

		// getters
		state_callback *next() const { return m_next; }

		// state
		state_callback *	m_next;					// pointer to next entry
		void *				m_param;				// function parameter
		prepost_func		m_func;					// pointer to the function
	};

	class state_entry
	{
	public:
		// construction/destruction
		state_entry(void *data, const char *name, UINT8 size, UINT32 count);

		// getters
		state_entry *next() const { return m_next; }

		// helpers
		void flip_data();

		// state
		state_entry *		m_next;					// pointer to next entry
		void *				m_data;					// pointer to the memory to save/restore
		astring				m_name;					// full name
		UINT8				m_typesize;				// size of the raw data type
		UINT32				m_typecount;			// number of items
		UINT32				m_offset;				// offset within the final structure
	};

	// internal state
	running_machine &		m_machine;				// reference to our machine
	bool					m_reg_allowed;			// are registrations allowed?
	int						m_illegal_regs;			// number of illegal registrations

	simple_list<state_entry> m_entry_list;			// list of reigstered entries
	simple_list<state_callback> m_presave_list;		// list of pre-save functions
	simple_list<state_callback> m_postload_list;	// list of post-load functions

	static const char s_magic_num[8];				// magic number for header
};


// template specializations to enumerate the fundamental atomic types you are allowed to save
ALLOW_SAVE_TYPE(bool);
ALLOW_SAVE_TYPE(INT8);
ALLOW_SAVE_TYPE(UINT8);
ALLOW_SAVE_TYPE(INT16);
ALLOW_SAVE_TYPE(UINT16);
ALLOW_SAVE_TYPE(INT32);
ALLOW_SAVE_TYPE(UINT32);
ALLOW_SAVE_TYPE(INT64);
ALLOW_SAVE_TYPE(UINT64);
ALLOW_SAVE_TYPE(PAIR);
ALLOW_SAVE_TYPE(PAIR64);
ALLOW_SAVE_TYPE(float);
ALLOW_SAVE_TYPE(double);
ALLOW_SAVE_TYPE(endianness_t);



//**************************************************************************
//  INLINE FUNCTIONS
//**************************************************************************

//-------------------------------------------------
//  save_item - specialized save_item for bitmaps
//-------------------------------------------------

template<>
inline void state_manager::save_item(const char *module, const char *tag, int index, bitmap_t &value, const char *name)
{
	save_memory(module, tag, index, name, value.base, value.bpp / 8, value.rowpixels * value.height);
}


//-------------------------------------------------
//  save_item - specialized save_item for attotimes
//-------------------------------------------------

template<>
inline void state_manager::save_item(const char *module, const char *tag, int index, attotime &value, const char *name)
{
	astring tempstr(name, ".attoseconds");
	save_memory(module, tag, index, tempstr, &value.attoseconds, sizeof(value.attoseconds));
	tempstr.cpy(name).cat(".seconds");
	save_memory(module, tag, index, tempstr, &value.seconds, sizeof(value.seconds));
}


#endif	/* __STATE_H__ */
