#include <camera.h>

#include <mario.h>
#include <world.h>
#include <base.h>
#include <keyboard.h>

static int y=0;
static int last_vy=0;
static int immobile=0;
static int distance=0;
static int delta_y=0; // the player can choose the y positionning of the camera with arrows

int cameraX() {return  min(max(mario.p.x-40,0),map_current->w*8-128);}
int cameraY() {return max(max(y-32,0)-delta_y,0);}

void cameraMove() // only vertical movement
{
	static int camera_vy=0;

	if (MKB_getKeyState(MK_UP) && abs(delta_y)<24) { camera_vy=0; delta_y-=4;}
	if (MKB_getKeyState(MK_DOWN) && abs(delta_y)<24) { camera_vy=0; delta_y+=4;}
	if (!MKB_getKeyState(MK_DOWN) && !MKB_getKeyState(MK_UP)) delta_y-=4*sgn(delta_y);

	if (mario.p.y==last_vy) immobile++;
	else
	{
		last_vy=mario.p.y;
		immobile=0;
	}
	if (mario.p.y-cameraY()-mario.p.h<16 || mario.p.y-cameraY()>54)
	{
		y+=4*sgn(mario.p.y-y);
	}

	if (immobile>=2)
	{
		//y+=(mario.p.y-y)/3;
		if (camera_vy==0) distance=2*(mario.p.y-y)*sgn(mario.p.y-y);

		//décéleration après avoir parvouru la moitié de la distance, sinon acceleration
		if (camera_vy*(camera_vy+1)>distance) camera_vy--;
		else camera_vy++;
		//y++;

		if (camera_vy<0) camera_vy=0;

		if (((y+camera_vy*sgn(mario.p.y-y)/2)-(mario.p.y))*sgn(mario.p.y-y)>0)
		{
			y=mario.p.y;
			camera_vy=0;
		}
		else
		y+=(camera_vy*sgn(mario.p.y-y))/2;

	}
	last_vy=mario.p.y;
}

void cameraAdjust()
{
	y=mario.p.y;
}

void cameraReset()
{
	y=0;
}