#include "plugin.h"

PLUGIN_HEADER
static struct plugin_api* rb;
	
#include "eval.c"
struct point
{
	int x;
	int y;
};

struct plot_conf
{
	int x_start;
	int x_end;
	int y_start;
	int y_end;
	int x_mod;
	int y_mod;
	int x_grid_step;
	int y_grid_step;
	char func[256];
};

struct point last_point;
bool use_last_point; /*Coordinates of last drawed point*/
/*bool exit;  true if we must exit app*/ 	
static struct plot_conf plot;




static void plot_set_default_values(void)
{
 plot.x_start = -(LCD_WIDTH/2);
 plot.x_end = (LCD_WIDTH/2);
 plot.y_start = -(LCD_HEIGHT/2);
 plot.y_end = (LCD_HEIGHT/2);
 plot.x_mod = 1;
 plot.y_mod = 1;
 plot.x_grid_step = 10;
 rb->strcpy(plot.func,"x*x") ;
}


static void draw_point(struct point p)
{
    if (!use_last_point)
	{
		rb->lcd_drawpixel(p.x,p.y);
		use_last_point = true;
	}else
	{
		rb->lcd_drawline(last_point.x,last_point.y,p.x,p.y);
	}
}

static struct point create_point(int _x, int _y)
{
	struct point tmp;

	tmp.x = _x;
	tmp.y = _y;

	return tmp;

}


static struct point coord_to_screen_pixel(struct point p)
{
	struct point tmp;

	tmp.x = (int)((LCD_WIDTH / 2)+p.x);
	tmp.y = (int)((LCD_HEIGHT / 2)-p.y);

	return tmp;

}

static void draw_grid(void)
{
	rb->lcd_set_background(LCD_WHITE);
	rb->lcd_set_foreground(LCD_BLACK);
	rb->lcd_vline(LCD_WIDTH/2,0,LCD_HEIGHT);
	rb->lcd_hline(0,LCD_WIDTH,LCD_HEIGHT/2);
	int i;
	int n=0;
	int sign=1;
	char buf[32];
	for (i=0; i < LCD_WIDTH/2; i+=sign*plot.x_grid_step*plot.x_mod)
	{
		
		rb->lcd_vline(LCD_WIDTH/2+i,LCD_HEIGHT/2-2,LCD_HEIGHT/2+2);
		rb->snprintf(buf,32,"%d",n);
		rb->lcd_putsxy(LCD_WIDTH/2+i+1,LCD_HEIGHT/2+4,buf);
		n+=sign*plot.x_grid_step;
	}


	n=0;
	for (i=0; i < LCD_WIDTH/2 ; i+=plot.x_grid_step*plot.x_mod)
	{
		rb->lcd_vline(LCD_WIDTH/2-i,LCD_HEIGHT/2-2,LCD_HEIGHT/2+2);
		rb->snprintf(buf,32,"%d",n);
		DEBUGF("%s",buf);
		rb->lcd_putsxy(LCD_WIDTH/2-i-1,LCD_HEIGHT/2+4,buf);
		n-=plot.x_grid_step;
	}
	
	
}

static int count(double x)
	{
		
	static double const_values[2];
	const_values[0] = x;
	const_values[1] = x;
	const_values[2] = 0;
		

	static const char *const_names[]={
    "x",
    "X",
    0
	};
	return (int)x*x;/*ff_eval(plot.func, const_values, const_names, NULL, NULL, NULL, NULL, NULL);*/
}

static void draw_plot(void)
{
	DEBUGF("Reach draw plot\n");
	double i=1.0;
    static struct point temp;
    
    rb->lcd_clear_display();
    draw_grid();
   
 
	for (i=plot.x_start;i<=plot.x_end;i+=(double)(LCD_WIDTH/plot.x_mod))
	{
		//DEBUGF("Per pixel countion i = 0.%d\n",i*100);
		temp.x = i*plot.x_mod;
		temp.y = i*i;/*(int)(count(i)*plot.y_mod);*/
		temp = coord_to_screen_pixel(temp);
		DEBUGF("ym %x\n",plot.y_mod);
		DEBUGF("y %x\n",temp.y);
		if ((temp.x<LCD_WIDTH)&(temp.x>0)&\
		   (temp.y<LCD_HEIGHT)&(temp.y>0))
		{
			draw_point(temp);
			last_point = temp;
		}
	}
	use_last_point = false; 
	rb->lcd_update();
	DEBUGF("Exit draw plot\n");
}


static bool start_grapher(void)
{

  int button, quit = 0;
  plot_set_default_values();
  draw_plot();
  
  while(!quit) {
    button=rb->button_get(true);
    switch(button) {
		case BUTTON_LEFT:
			if (plot.x_mod>1) plot.x_mod--;
			draw_plot();	
			break;
		case BUTTON_RIGHT:
			plot.x_mod++;
			draw_plot();
			break;
		case BUTTON_UP:
			plot.y_mod++;
			draw_plot();
			break;
		case BUTTON_DOWN:
			if (plot.y_mod>1) plot.y_mod--;
			draw_plot();
			break;
        case BUTTON_REC:
			quit=true;
			break;
    }
	}
  
	return true;
	
}



static bool show_main_menu(void)
{
    int m;
    bool result;
	bool rs = true;
    static const struct menu_item items[] = {
    	 { "Grapher", start_grapher },
    	 { "Calculator", NULL },
    	 { "Exit", NULL },
    };
    m = rb->menu_init(items, sizeof(items) / sizeof(*items),
                      NULL, NULL, NULL, NULL);

    result = rb->menu_run(m);
    rb->menu_exit(m);

    return rs;
}

enum plugin_status plugin_start(struct plugin_api* api, void* parameter)
{
    (void)parameter;

    
    rb = api;
    
    show_main_menu();
    
      
    return PLUGIN_OK;
}