/*
	Homebrew Z80 TV GAME SYSTEM Emulator 'eZ80TVGAME'

	Author : Takeda.Toshiya
	Date   : 2015.04.28-

	[ virtual machine ]
*/

// http://w01.tp1.jp/~a571632211/z80tvgame/index.html

#include "z80tvgame.h"
#include "../../emu.h"
#include "../device.h"
#include "../event.h"

#ifdef _USE_I8255
#include "../i8255.h"
#else
#include "../z80pio.h"
#endif
#include "../pcm1bit.h"
#include "../z80.h"

#ifdef USE_DEBUGGER
#include "../debugger.h"
#endif

#include "joystick.h"
#include "memory.h"

// ----------------------------------------------------------------------------
// initialize
// ----------------------------------------------------------------------------

VM::VM(EMU* parent_emu) : emu(parent_emu)
{
	// create devices
	first_device = last_device = NULL;
	dummy = new DEVICE(this, emu);	// must be 1st device
	event = new EVENT(this, emu);	// must be 2nd device
	dummy->set_device_name(_T("1st Dummy"));
	
#ifdef _USE_I8255
	pio = new I8255(this, emu);
#else
	pio = new Z80PIO(this, emu);
#endif
	pcm = new PCM1BIT(this, emu);
	cpu = new Z80(this, emu);
	
	joystick = new JOYSTICK(this, emu);
	memory = new MEMORY(this, emu);
	
	// set contexts
	event->set_context_cpu(cpu);
	event->set_context_sound(pcm);

	// Sound:: Force realtime rendering. This is temporally fix. 20161024 K.O
	//pcm->set_realtime_render(true);

#ifdef _USE_I8255
	pio->set_context_port_c(pcm, SIG_PCM1BIT_SIGNAL, 1, 0);
#else
	pio->set_context_port_b(pcm, SIG_PCM1BIT_SIGNAL, 1, 0);
#endif
	joystick->set_context_pio(pio);
	
	// cpu bus
	cpu->set_context_mem(memory);
	cpu->set_context_io(pio);
	cpu->set_context_intr(dummy);
#ifdef USE_DEBUGGER
	cpu->set_context_debugger(new DEBUGGER(this, emu));
#endif
	
	// initialize all devices
	for(DEVICE* device = first_device; device; device = device->next_device) {
		device->initialize();
	}
}

VM::~VM()
{
	// delete all devices
	for(DEVICE* device = first_device; device;) {
		DEVICE *next_device = device->next_device;
		device->release();
		delete device;
		device = next_device;
	}
}

DEVICE* VM::get_device(int id)
{
	for(DEVICE* device = first_device; device; device = device->next_device) {
		if(device->this_device_id == id) {
			return device;
		}
	}
	return NULL;
}

// ----------------------------------------------------------------------------
// debugger
// ----------------------------------------------------------------------------

#ifdef USE_DEBUGGER
DEVICE *VM::get_cpu(int index)
{
	if(index == 0) {
		return cpu;
	}
	return NULL;
}
#endif

// ----------------------------------------------------------------------------
// drive virtual machine
// ----------------------------------------------------------------------------

void VM::reset()
{
	// reset all devices
	for(DEVICE* device = first_device; device; device = device->next_device) {
		device->reset();
	}
}

void VM::run()
{
	event->drive();
}

// ----------------------------------------------------------------------------
// draw screen
// ----------------------------------------------------------------------------

void VM::draw_screen()
{
	memory->draw_screen();
}

// ----------------------------------------------------------------------------
// soud manager
// ----------------------------------------------------------------------------

void VM::initialize_sound(int rate, int samples)
{
	// init sound manager
	event->initialize_sound(rate, samples);
	
	// init sound gen
	pcm->initialize_sound(rate, 8000);
}

uint16_t* VM::create_sound(int* extra_frames)
{
	return event->create_sound(extra_frames);
}

int VM::get_sound_buffer_ptr()
{
	return event->get_sound_buffer_ptr();
}

#ifdef USE_SOUND_VOLUME
void VM::set_sound_device_volume(int ch, int decibel_l, int decibel_r)
{
	if(ch == 0) {
		pcm->set_volume(0, decibel_l, decibel_r);
	}
}
#endif

// ----------------------------------------------------------------------------
// user interface
// ----------------------------------------------------------------------------

void VM::open_cart(int drv, const _TCHAR* file_path)
{
	if(drv == 0) {
		memory->open_cart(file_path);
		reset();
	}
}

void VM::close_cart(int drv)
{
	if(drv == 0) {
		memory->close_cart();
		reset();
	}
}

bool VM::is_cart_inserted(int drv)
{
	if(drv == 0) {
		return memory->is_cart_inserted();
	} else {
		return false;
	}
}

bool VM::is_frame_skippable()
{
	return event->is_frame_skippable();
}

void VM::update_config()
{
	for(DEVICE* device = first_device; device; device = device->next_device) {
		device->update_config();
	}
}

#define STATE_VERSION	1

void VM::save_state(FILEIO* state_fio)
{
	state_fio->FputUint32(STATE_VERSION);
	
	for(DEVICE* device = first_device; device; device = device->next_device) {
		device->save_state(state_fio);
	}
}

bool VM::load_state(FILEIO* state_fio)
{
	if(state_fio->FgetUint32() != STATE_VERSION) {
		return false;
	}
	for(DEVICE* device = first_device; device; device = device->next_device) {
		if(!device->load_state(state_fio)) {
			return false;
		}
	}
	return true;
}

