/*
 *	4Kb Intro startup by Pedro Gil (Balrog Soft)
 *	           www.amigaskool.net
 *
 *  TinyGL and AHI device startup code,
 *  and music synth for 4k intros.
 *  The song was ripped from howagen intro by tonic.
 *
 *  Special thanks to Piru for his small opts,
 *  and Morphzone.org people!
 *
 */

#include <stdio.h>
#include <limits.h>

#include <devices/ahi.h>

#include <proto/exec.h>
#include <proto/dos.h>
#include <proto/tinygl.h>
#include <proto/ahi.h>


#define ubyte   unsigned char
#define uint    unsigned int

#define byte    signed char

#ifndef M_PI
#define M_PI  3.14159265
#define M_PI2 6.283185
#endif

// Sinus and cosinus arrays have 720 elements

#define TABLE_DEGREES	720
#define DEGREE_STEP     M_PI2 / TABLE_DEGREES

// Define our ahi device for 8 bits 
// signed mono buffer with a frequency
// of 8000 samples

#define FREQUENCY  		8000
#define TYPE       		AHIST_M8S
#define BUFFERSIZE 		24000

static void display(void);
static void	keys(unsigned char c, int x, int y);
static void synth4k(void);


struct ExecBase    *SysBase;
struct Library 	   *TinyGLBase;
					 

GLContext *__tglContext;

static struct MsgPort    *AHImp     = NULL;
static struct AHIRequest *AHIios1	= NULL;
static struct AHIRequest *AHIios2	= NULL;
static struct AHIRequest *link 		= NULL;

static struct Message *wbstartupmsg = NULL;
static struct Process *self = NULL;

static void  *tmp;
static BOOL  init = TRUE;

static byte  AHIDevice;

// Here are defined two audio buffers, 
// it is similar to a screen double buffer
static byte   buffer1[BUFFERSIZE], buffer2[BUFFERSIZE];
static byte  *p1=buffer1, *p2=buffer2;
static uint  signals;
static int   t, i, j, n;

// Our sinus and cosinus tables
static float  sinus[TABLE_DEGREES], cosinus[TABLE_DEGREES],
			   a = 0, b = 1, c, d = DEGREE_STEP;

#define __TEXTSECTION__ __attribute__((section(".text")))


#ifdef NOSTARTUPFILES
int entry(void)
#else
int main(void)
#endif
{
  SysBase    = *(struct ExecBase **) 4;
  
  wbstartupmsg = 0;
  self = (struct Process *) FindTask(0);
  if (self->pr_CLI == 0)
  {
	WaitPort(&self->pr_MsgPort);
	wbstartupmsg = GetMsg(&self->pr_MsgPort);
  }
 
  TinyGLBase = OpenLibrary("tinygl.library",   50);

  if (TinyGLBase)
  {

    // Initialize AHI device

	AHImp=CreateMsgPort();
	#ifndef REMOVE
	if(AHImp != NULL)
	{
	#endif
		AHIios1 = (struct AHIRequest *) CreateIORequest(AHImp, sizeof(struct AHIRequest));
		AHIios1->ahir_Version = 4;
		AHIDevice = OpenDevice(AHINAME, 0, (struct IORequest *)AHIios1, 0);
	#ifndef REMOVE
    }
	#endif

	// Make a copy of the request (for double buffering)

	AHIios2 = AllocVec(sizeof(struct AHIRequest), MEMF_ANY);
	CopyMem(AHIios1, AHIios2, sizeof(struct AHIRequest));
	
	// Generate sinus and cosinus tables
	i = TABLE_DEGREES;
	while (i) 
	{
		c = a + b * d;
		b = b - c * d;
		sinus  [TABLE_DEGREES-i] = c;
		cosinus[TABLE_DEGREES-i] = b;
		a = c;
		i--;
	}
	c = 0;
	
	__tglContext = GLInit();
	if (__tglContext)
	{
		// Initialize TinyGL
		
        glutInit(NULL,NULL);

		glutInitDisplayMode(GLUT_RGBA);

		#ifndef REMOVE
		glutInitWindowSize(640, 480);
		#endif

		glutFullScreen();
		
		glutCreateWindow(NULL);

		#ifndef REMOVE
		glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
		#endif
		
		// Setting blending settings

		glEnable(GL_BLEND);		// Enable Blending
		
		glBlendFunc(GL_SRC_ALPHA, GL_ONE);
		
        glEnableClientState(GL_VERTEX_ARRAY);

		// Setting projection, P2D define a 
		// 2D projection for 2d graphics.
		glMatrixMode(GL_PROJECTION);
		
		#ifdef P2D
		glOrtho(320.0f, -320.0f,
			  240.0f, -240.0f,
			   -1.0f, 1.0f);
		#else
		gluPerspective(80, 1.333333f, 1.0, 500.0);
		glTranslatef(0.0f, 0.0f, -240.0f);
		#endif

		glMatrixMode(GL_MODELVIEW);
		
		// Some unused stuff
		
		//glScalef(2.0f,2.0f,0.0f);
		//glEnable(GL_LINE_SMOOTH);

		//glHint(TGL_CORRECT_NORMALS_HINT, GL_FASTEST);
		//glHint(GL_LINE_SMOOTH_HINT, GL_NICEST);
		
		// Define our main key and idle functions
		
        glutKeyboardFunc(keys);
		
        glutIdleFunc(display);

		// And enter to the main loop.
		
		glutMainLoop();

		// Close TinyGL Context
		GLClose(__tglContext);
	}

  	// Abort any pending AHI iorequests
	AbortIO((struct IORequest *) AHIios1);
	WaitIO((struct IORequest *) AHIios1);

	if(link)  // Only if the second request was started
	{
		AbortIO((struct IORequest *) AHIios2);
		WaitIO((struct IORequest *) AHIios2);
	}  

	if(!AHIDevice)
		CloseDevice((struct IORequest *)AHIios1);
	
	DeleteIORequest((struct IORequest *)AHIios1);
	FreeVec(AHIios2);
		
	// Close TinyGL lib
	CloseLibrary(TinyGLBase);
  }
  
  if (wbstartupmsg)
  {
    Forbid();
    ReplyMsg(wbstartupmsg);
  }
  
  return 0;
}


static void	keys(unsigned char c, int x, int y)
{
	// Send a fake CTRL+C signal to exit
	if (c == 0x1b)
	{
		SetSignal(SIGBREAKF_CTRL_C, SIGBREAKF_CTRL_C);
	}
}

static void display(void)
{	 
	// Ahi device handle code

	// Send io request to the device
	if ((signals & (1L << AHImp->mp_SigBit) || init))
	{
		if (init && link)
			init = FALSE;
		if (!link)
            synth4k();
	//	  AHIios1->ahir_Std.io_Message.mn_Node.ln_Pri = 0;
		AHIios1->ahir_Std.io_Command  = CMD_WRITE;
		AHIios1->ahir_Std.io_Data     = p1;
		AHIios1->ahir_Std.io_Length   = BUFFERSIZE;
	//	  AHIios1->ahir_Std.io_Offset   = 0;
		AHIios1->ahir_Frequency       = FREQUENCY;
		AHIios1->ahir_Type            = TYPE;
		AHIios1->ahir_Volume          = 0x10000;          // Full volume
		AHIios1->ahir_Position        = 0x8000;           // Centered
		AHIios1->ahir_Link            = link;
		SendIO((struct IORequest *) AHIios1);
	}

	// Check if there are any signals from ahi device
	if(link)
	{
		// Send a fake signal to not stop the loop
		SetSignal(SIGBREAKF_CTRL_D, SIGBREAKF_CTRL_D);
        signals = Wait(SIGBREAKF_CTRL_D | (1L << AHImp->mp_SigBit));
	}
	
	link = AHIios1;
   
	// Swap ahi buffers
	if ((signals & (1L << AHImp->mp_SigBit)) || init)
    {
		if (!init)
			WaitIO((struct IORequest *) AHIios2);
		
		// Swap buffer and request pointers, and restart
		tmp    = p1;
		p1     = p2;
		p2     = tmp;
		
        synth4k();

		tmp    = AHIios1;
		AHIios1 = AHIios2;
		AHIios2 = tmp;
	}

	// Here goes the drawing stuff!
	
	glClear(GL_COLOR_BUFFER_BIT);	// Clear Screen Buffer

			
	glutSwapBuffers();	

}

// This is the future 4k synth
static void synth4k(void)
{

}

#ifdef NOSTARTUPFILES
/* __abox__ symbol is required or else the binary is loaded as PowerUP app */
const int __abox__ __TEXTSECTION__ = 1;
#endif

CC 		= gcc
CPP		= g++
LD 		= ld
STRIP 	= strip
CFLAGS 	= -O1 -s  -fomit-frame-pointer -noixemul  -ISDK:tinygl-sdk/include

NOSTARTUPFILES  = 1
REMOVE 			= 1
2D_PROJECTION	= 1

ifdef NOSTARTUPFILES
	CFLAGS+= -DNOSTARTUPFILES -nostartfiles
endif

ifdef REMOVE
	CFLAGS+= -DREMOVE
endif

ifdef 2D_PROJECTION
	CFLAGS+= -DP2D
endif

INTRO_OBJS = intro.o

all: intro

intro: $(INTRO_OBJS)
	$(CC) $(CFLAGS) -o $@ $(INTRO_OBJS)
	$(STRIP) -s -R .comment -R .gnu.version -R .gnu.version_d -R .gnu.version_r $@
	chmod u+x $@

intro_map:
	$(CC) $(CFLAGS) intro.c -Wl,-Map=foobar.map,--traditional-format

intro_asm:
	$(CC) $(CFLAGS) -save-temps -o $@ $(INTRO_OBJS)
	
clean:
	rm -f *.o intro

copy lzmaLoader_shared ram:intro
lzma e intro -so >> ram:intro