/* client/camera.cc
   This file is part of the Osirion project and is distributed under 
   the terms and conditions of the GNU General Public License version 2 
*/

#include "common/functions.h"
#include "game/game.h"
#include "gl/osiriongl.h"

namespace camera
{
enum Mode {Free, Track};
Mode mode = Track;

const float track_pitch = -15.0f; // default tracking pitch
const float offset_inc = 5.0f; // default offset increment

float yaw = 0; // current yaw, angle in XZ plane, positive is looking left
float yaw_target = 0; // target yaw

float pitch = -45.0f; // current pitch, angle in XY, positive is looking up
float pitch_target = track_pitch; // target pitch

float distance = 0.4f; // distance from the eye to the target


void draw(float elapsed) 
{	
	if (mode == Track) {
		yaw_target = game::ship.yaw;
	}

	// adjust yaw
	float d = degreesf(yaw - yaw_target);
	yaw = degreesf( yaw - d * elapsed) ;
	
	// adjust pitch target
	d = degreesf(pitch - pitch_target);
	pitch = degreesf( pitch - d *elapsed);

	switch (mode) {
	case Free:
		gl::translate(1.0f+distance, -distance, 0.0f);
		gl::rotate(-pitch, 0, 0, 1.0f);
		gl::rotate(-yaw, 0, 1.0f, 0);
		break;
	case Track:
		gl::translate(1.0f+distance, -distance , 0.0f);
		gl::rotate(-pitch, 0, 0, 1.0f);
		gl::rotate(-yaw, 0, 1.0f, 0);
		break;
	default:
		break;
	}
}

void rotate_right()
{
	if (mode == Free ) {
		yaw_target = degreesf(  yaw_target + offset_inc);
	}
}

void rotate_left()
{
	if (mode == Free ) {
		yaw_target = degreesf(  yaw_target - offset_inc);
	}
}

void rotate_up()
{
	if (mode == Free ) {
		pitch_target = pitch_target + offset_inc;
		if (pitch_target > 90.0f) pitch_target = 90.0f;
	}
}

void rotate_down()
{
	if (mode == Free ) {
		pitch_target = pitch_target - offset_inc;
		if (pitch_target < -90.0f) pitch_target = -90.0f;
	}
}

void nextmode() {
	switch(mode) {
	case Free:
		// switch camera to Track mode
		mode = Track;
		yaw_target = game::ship.yaw;
		yaw = yaw_target;
		pitch_target = track_pitch;
		pitch = pitch_target;
		break;
	case Track:
		// switch camera to Free mode
		mode = Free;
		yaw_target = game::ship.yaw;
		yaw = yaw_target;
		pitch_target = track_pitch;
		pitch = pitch_target;
		break;
	default:
		break;
	}
}

} //namespace camera