// Vasilije Dugalic 23/2020

#define GLM_ENABLE_EXPERIMENTAL
#define _USE_MATH_DEFINES
#include <GL/freeglut.h>
#include <glm/vec3.hpp>
#include <glm/mat4x4.hpp>
#include <glm/gtx/transform.hpp>
#include <glm/gtx/rotate_vector.hpp>
#include <vector>
#include <stdio.h>
#include <math.h>

using namespace glm;
using namespace std;

#define MOVING_CONST 0.1
#define ROTATION_CONST 3.14f / 180.f
#define LOOK_MOVEMENT_CONST 0.1f

/*--------------------------------------------------*/

char title[] = "Prozor";
int FPS = 60;
vec3 CameraPosition(1.0, 0.5, 1.0);
vec3 LookAt_vector(0.0, 0.0, 0.0);
vec3 LookUp_vector(0.0, 1.0, 0.0);
vector<vec3> coordinateSystem;

const int circle_dots = 50;
const float height = 480;
const float ratio = 16.f / 9.f;
double upDownAngle = 0;
int currentSpeed = 1;
float arrowRotate = 0.f;

vec3 operator* (mat4x4 mat, vec3 vec)
{
	vec4 v(vec.x, vec.y, vec.z, 1.f);
	v = mat * v;
	return vec3(v.x, v.y, v.z);
}

vector<vec3> operator* (mat4x4 mat, vector<vec3> vectors)
{
	for (int i = 0; i < vectors.size(); i++)
		vectors[i] = mat * vectors[i];
	return vectors;
}


//o GLUT_BITMAP_TIMES_ROMAN_24
//o GLUT_BITMAP_TIMES_ROMAN_10
//o GLUT_BITMAP_HELVETICA_18

void RenderString(float x, float y, void* font, double r, double g, double b)
{
	glColor3f(r, g, b);
	glRasterPos2f(x, y);

	char s[100];
	sprintf(s, "x = %.2lf\ny = %.2lf\nz = %.2lf", CameraPosition.x, CameraPosition.y, CameraPosition.z);
	glutBitmapString(font, (const unsigned char*)s);
}

/*--------------------------------------------------*/
void createCoordinates()
{
	coordinateSystem.resize(4);
	coordinateSystem[0] = vec3(0.0, 0.0, 0.0);
	coordinateSystem[1] = vec3(1.0, 0.0, 0.0);
	coordinateSystem[2] = vec3(0.0, 1.0, 0.0);
	coordinateSystem[3] = vec3(0.0, 0.0, 1.0);

	mat4 MT;
	MT = translate(vec3(0.0, -0.75, 0.0));

	coordinateSystem = MT * coordinateSystem;
}



void drawCoordinates()
{
	glLineWidth(2.0);
	glBegin(GL_LINES);
	// X axis
	glColor3f(1.0f, 0.0f, 0.0f); // Red
	glVertex3d(coordinateSystem[0].x, coordinateSystem[0].y, coordinateSystem[0].z);
	glVertex3d(coordinateSystem[1].x, coordinateSystem[1].y, coordinateSystem[1].z);
	// Y axis
	glColor3f(0.0f, 1.0f, 0.0f); // Green
	glVertex3d(coordinateSystem[0].x, coordinateSystem[0].y, coordinateSystem[0].z);
	glVertex3d(coordinateSystem[2].x, coordinateSystem[2].y, coordinateSystem[2].z);
	// Z axis
	glColor3f(0.0f, 0.0f, 1.0f); // Blue
	glVertex3d(coordinateSystem[0].x, coordinateSystem[0].y, coordinateSystem[0].z);
	glVertex3d(coordinateSystem[3].x, coordinateSystem[3].y, coordinateSystem[3].z);
	glEnd();
}

vector<vec3> kreirajKruznicu(vec3 centar, float r, int brojTacaka)
{
	vector<vec3> kruznica;
	kruznica.resize(brojTacaka);

	float fi = 2 * M_PI / brojTacaka;

	mat4x4 matricaRotacijeY = rotate(fi, vec3(0, 1, 0));
	mat4x4 matricaTranslacije = translate(centar);

	kruznica[0] = vec3(r, 0, 0);
	for (int i = 1; i < brojTacaka; i++)
	{
		kruznica[i] = matricaRotacijeY * kruznica[i - 1];
	}

	for (int i = 0; i < brojTacaka; i++)
	{
		kruznica[i] = matricaTranslacije * kruznica[i];
	}

	return kruznica;
}

vector<vector<vec3>> kreirajLoptu(float r, int brojTacakaKruznice, int brojKruznica)
{
	vector<vector<vec3>> lopta;
	lopta.resize(brojKruznica);

	for (int i = 0; i < brojKruznica; i++)
	{
		lopta[i].resize(brojTacakaKruznice);
	}

	float fi = 2 * M_PI / brojKruznica;
	mat4x4 matricaRotacijeZ = rotate(fi, vec3(0, 0, 1));

	lopta[0] = kreirajKruznicu(vec3(0, 0, 0), r, brojTacakaKruznice);
	for (int i = 1; i < brojKruznica; i++)
	{
		lopta[i] = matricaRotacijeZ * lopta[i - 1];
	}

	return lopta;
}

void nacrtaj(GLenum mode, vector<vec3>& tacke)
{
	glBegin(mode);
	for (int i = 0; i < tacke.size(); i++)
	{
		glVertex3f(tacke[i].x, tacke[i].y, tacke[i].z);
	}
	glEnd();
}

void spojiKruznice(vector<vec3>& prva, vector<vec3>& druga)
{
	vector<vec3> poligon;
	poligon.resize(4);

	int n = prva.size();
	for (int i = 0; i < n - 1; i++)
	{
		poligon[0] = prva[i];
		poligon[1] = druga[i];
		poligon[2] = druga[i + 1];
		poligon[3] = prva[i + 1];
		nacrtaj(GL_POLYGON, poligon);
	}

	poligon[0] = prva[n - 1];
	poligon[1] = druga[n - 1];
	poligon[2] = druga[0];
	poligon[3] = prva[0];
	nacrtaj(GL_POLYGON, poligon);
}



void nacrtajLoptu(vector<vector<vec3>>& lopta)
{
	float r = 0.1f;
	float g = 0.1f;
	float b = 0.1f;
	nacrtaj(GL_POLYGON, lopta[0]);

	int n = lopta.size();
	for (int i = 1; i < n; i++)
	{
		glColor3f(r, g, b);
		spojiKruznice(lopta[i - 1], lopta[i]);
		r += 0.001;
		g += 0.001;
		b += 0.001;
	}
}

void transformisi(vector<vec3>& tacke, mat4x4 matricaTransformacije)
{
	for (int i = 0; i < tacke.size(); i++)
	{
		tacke[i] = matricaTransformacije * tacke[i];
	}
}

float radian(float ugaoStepeni)
{
	return M_PI / 180 * ugaoStepeni;
}

vector<vector<vec3>> kreirajValjak(vec3 pozicija, float r, float h, float ugaoStepeni, float brojTacakaKruznice)
{
	vector<vector<vec3>> valjak;
	valjak.resize(2);

	valjak[0] = kreirajKruznicu(vec3(0, 0, 0), r, brojTacakaKruznice);
	valjak[1] = kreirajKruznicu(vec3(0, h, 0), r, brojTacakaKruznice);

	float ugao = radian(ugaoStepeni);
	mat4x4 matricaRotacijeZ = rotate(ugao, vec3(0, 0, 1));
	transformisi(valjak[0], matricaRotacijeZ);
	transformisi(valjak[1], matricaRotacijeZ);

	mat4x4 matricaTranslacije = translate(pozicija);
	transformisi(valjak[0], matricaTranslacije);
	transformisi(valjak[1], matricaTranslacije);

	return valjak;
}

void nacrtajValjak(vector<vector<vec3>>& valjak)
{
	vector<vec3> poligon;
	poligon.resize(4);

	nacrtaj(GL_POLYGON, valjak[0]);
	nacrtaj(GL_POLYGON, valjak[1]);

	int n = valjak[0].size();
	for (int i = 0; i < n - 1; i++)
	{
		poligon[0] = valjak[0][i];
		poligon[1] = valjak[0][i + 1];
		poligon[2] = valjak[1][i + 1];
		poligon[3] = valjak[1][i];
		nacrtaj(GL_POLYGON, poligon);
	}

	poligon[0] = valjak[0][n - 1];
	poligon[1] = valjak[0][0];
	poligon[2] = valjak[1][0];
	poligon[3] = valjak[1][n - 1];
	nacrtaj(GL_POLYGON, poligon);
}

vector<vec3> kreirajKupu(vec3 pozicija, float r, int brojTacakaKruznice, float h, float ugaoStepeniY, float ugaoStepeniZ)
{
	vector<vec3> kupa;
	kupa = kreirajKruznicu(vec3(0, 0, 0), r, brojTacakaKruznice);
	kupa.push_back(vec3(0, h, 0));

	float ugaoZ = radian(ugaoStepeniZ);
	float ugaoY = radian(ugaoStepeniY);
	mat4x4 matricaRotacijeZ = rotate(ugaoZ, vec3(1, 0, 0));
	mat4x4 matricaRotacijeY = rotate(ugaoY, vec3(0, 1, 0));
	mat4x4 matricaTranslacije = translate(pozicija);
	mat4x4 matricaTransformacije = matricaTranslacije * matricaRotacijeY * matricaRotacijeZ;

	transformisi(kupa, matricaTransformacije);

	return kupa;
}

void nacrtajKupu(vector<vec3>& kupa)
{
	vector<vec3> trougao;
	trougao.resize(3);

	int n = kupa.size();
	for (int i = 0; i < n - 2; i++)
	{
		trougao[0] = kupa[i];
		trougao[1] = kupa[i + 1];
		trougao[2] = kupa[n - 1];
		nacrtaj(GL_TRIANGLES, trougao);
	}

	trougao[0] = kupa[n - 1];
	trougao[1] = kupa[0];
	trougao[2] = kupa[n - 1];
	nacrtaj(GL_TRIANGLES, trougao);
}

void display(void)
{
	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

	glMatrixMode(GL_MODELVIEW);
	glLoadIdentity();
	glMatrixMode(GL_PROJECTION);
	glLoadIdentity();

	gluPerspective(80.f, 16.f / 9.f, 0.1f, 50.f);
	gluLookAt(
		CameraPosition.x, CameraPosition.y, CameraPosition.z,
		LookAt_vector.x, LookAt_vector.y, LookAt_vector.z,
		LookUp_vector.x, LookUp_vector.y, LookUp_vector.z
	);

	vector<vector<vec3>> lopta = kreirajLoptu(0.2, 64, 64);
	nacrtajLoptu(lopta);

	vector<vector<vec3>> valjakIspodLopte = kreirajValjak(vec3(-0.05, 0.18, 0), 0.05, 0.05, 20, 64);
	nacrtajValjak(valjakIspodLopte);

	// glavna drska
	vector<vector<vec3>> drska = kreirajValjak(vec3(-0.06, 0.205, 0), 0.03, 0.85, 20, 64);
	nacrtajValjak(drska);

	glColor3f(0.75, 0.71, 0.71);
	vector<vector<vec3>> siljci;
	siljci.resize(12);

	float rKupe = 0.03;
	float hKupe = 0.15;

	siljci[0] = kreirajKupu(vec3(0.0, 0.0, 0.2), rKupe, 128, hKupe, 0, 90);
	siljci[1] = kreirajKupu(vec3(0.2, 0.0, 0.0), rKupe, 128, hKupe, 90, 90);
	siljci[2] = kreirajKupu(vec3(0.0, 0.0, -0.2), rKupe, 128, hKupe, 180, 90);
	siljci[3] = kreirajKupu(vec3(-0.2, 0.0, 0.0), rKupe, 128, hKupe, 270, 90);
	siljci[4] = kreirajKupu(vec3(0.12, 0.1, 0.1), rKupe, 128, hKupe, 45, 45);
	siljci[5] = kreirajKupu(vec3(0.12, 0.1, -0.1), rKupe, 128, hKupe, 135, 45);
	siljci[6] = kreirajKupu(vec3(-0.12, 0.1, -0.1), rKupe, 128, hKupe, 225, 45);
	siljci[7] = kreirajKupu(vec3(-0.12, 0.1, 0.1), rKupe, 128, hKupe, 315, 45);
	siljci[8] = kreirajKupu(vec3(0.12, -0.1, 0.1), rKupe, 128, hKupe, 45, 135);
	siljci[9] = kreirajKupu(vec3(0.12, -0.1, -0.1), rKupe, 128, hKupe, 135, 135);
	siljci[10] = kreirajKupu(vec3(-0.12, -0.1, -0.1), rKupe, 128, hKupe, 225, 135);
	siljci[11] = kreirajKupu(vec3(-0.12, -0.1, 0.1), rKupe, 128, hKupe, 315, 135);

	for (int i = 0; i < siljci.size(); i++)
		nacrtajKupu(siljci[i]);

	//drawCoordinates();


	glMatrixMode(GL_MODELVIEW);
	glLoadIdentity();
	glMatrixMode(GL_PROJECTION);
	glLoadIdentity();

	glDisable(GL_DEPTH_TEST);



	glEnable(GL_DEPTH_TEST);

	glutSwapBuffers();
}

void timer(int v)
{
	glMatrixMode(GL_MODELVIEW);
	glLoadIdentity();
	gluLookAt(
		CameraPosition.x, CameraPosition.y, CameraPosition.z,
		LookAt_vector.x, LookAt_vector.y, LookAt_vector.z,
		LookUp_vector.x, LookUp_vector.y, LookUp_vector.z
	);


	glutTimerFunc(1000 / FPS, timer, v);
	glutPostRedisplay();
}

void reshape(GLsizei width, GLsizei height)
{
	if (height * ratio <= width)
		width = ratio * height;
	else
		height = width / ratio;
	glViewport(0, 0, width, height);
}

void PrintVector(vec3 vec)
{
	printf("%.2f %.2f %.2f\n", vec.x, vec.y, vec.z);
}

void MoveForward()
{
	mat4x4 mt;
	vec3 v = LookAt_vector - CameraPosition;
	v = normalize(v);
	v.y = 0.f;
	v = v * (currentSpeed * (float)MOVING_CONST);

	mt = translate(mat4x4(1.f), v);

	LookAt_vector = mt * LookAt_vector;
	CameraPosition = mt * CameraPosition;
}

void MoveBackward()
{
	mat4x4 mt;
	vec3 v = LookAt_vector - CameraPosition;
	v.y = 0.f;
	v = normalize(v);

	v = -v * (currentSpeed * (float)MOVING_CONST);

	mt = translate(mat4x4(1.f), v);
	LookAt_vector = mt * LookAt_vector;
	CameraPosition = mt * CameraPosition;
}

void MoveLeft()
{
	mat4x4 mt;
	vec3 f = LookAt_vector - CameraPosition;
	vec3 w = cross(LookUp_vector, f);

	w = normalize(w);
	w = w * (currentSpeed * (float)MOVING_CONST);

	mt = translate(mat4x4(1.f), w);

	CameraPosition = mt * CameraPosition;
	LookAt_vector = mt * LookAt_vector;
}

void MoveRight()
{
	mat4x4 mt;
	vec3 f = LookAt_vector - CameraPosition;
	vec3 w = cross(LookUp_vector, f);

	w = normalize(w);
	w = -w * (currentSpeed * (float)MOVING_CONST);

	mt = translate(mat4x4(1.f), w);

	CameraPosition = mt * CameraPosition;
	LookAt_vector = mt * LookAt_vector;
}

void TurnLeft()
{
	mat4x4 mt, identityMat, mt1, mt2, mtr;

	identityMat = mat4x4(1.f);
	mt1 = translate(identityMat, vec3(CameraPosition.x, CameraPosition.y, CameraPosition.z));
	mtr = rotate(identityMat, ROTATION_CONST, vec3(0.f, 1.f, 0.f));
	mt2 = translate(identityMat, vec3(-CameraPosition.x, -CameraPosition.y, -CameraPosition.z));

	mt = mt1 * mtr * mt2;
	LookAt_vector = mt * LookAt_vector;

	arrowRotate += ROTATION_CONST;
}

void TurnRight()
{
	mat4x4 mt, identityMat, mt1, mt2, mtr;

	identityMat = mat4x4(1.f);
	mt1 = translate(identityMat, vec3(CameraPosition.x, CameraPosition.y, CameraPosition.z));
	mtr = rotate(identityMat, -ROTATION_CONST, vec3(0.f, 1.f, 0.f));
	mt2 = translate(identityMat, vec3(-CameraPosition.x, -CameraPosition.y, -CameraPosition.z));

	mt = mt1 * mtr * mt2;
	LookAt_vector = mt * LookAt_vector;

	arrowRotate -= ROTATION_CONST;
}

void TurnUp()
{
	mat4x4 mt, mt1, mt2, mtr;
	vec3 f = LookAt_vector - CameraPosition;
	vec3 w = cross(f, LookUp_vector);

	w = normalize(w);

	if (upDownAngle + ROTATION_CONST < (float)M_PI_2)
	{
		mt1 = translate(mat4x4(1.f), vec3(-CameraPosition.x, -CameraPosition.y, -CameraPosition.z));
		mtr = rotate(mat4x4(1.f), ROTATION_CONST, w);
		mt2 = translate(mat4x4(1.f), vec3(CameraPosition.x, CameraPosition.y, CameraPosition.z));

		mt = mt2 * mtr * mt1;

		LookAt_vector = mt * LookAt_vector;

		upDownAngle += ROTATION_CONST;
	}
}

void TurnDown()
{
	mat4x4 mt, mt1, mt2, mtr;
	vec3 f = LookAt_vector - CameraPosition;
	vec3 w = cross(f, LookUp_vector);

	w = normalize(w);

	if (upDownAngle - ROTATION_CONST > (float)-M_PI_2)
	{
		mt1 = translate(mat4x4(1.f), vec3(-CameraPosition.x, -CameraPosition.y, -CameraPosition.z));
		mtr = rotate(mat4x4(1.f), -ROTATION_CONST, w);
		mt2 = translate(mat4x4(1.f), vec3(CameraPosition.x, CameraPosition.y, CameraPosition.z));

		mt = mt2 * mtr * mt1;

		LookAt_vector = mt * LookAt_vector;
		// LookUp_vector = mt * LookUp_vector;

		upDownAngle -= ROTATION_CONST;
	}
}

void SpeedUp()
{
	if (currentSpeed < 5)
		++currentSpeed;
}

void SpeedDown()
{
	if (currentSpeed > 0)
		--currentSpeed;
}

void initGL(void)
{
	glClearColor(1.0f, 1.0f, 1.0f, 1.0f);
	glShadeModel(GL_FLAT);
	glEnable(GL_DEPTH_TEST);
}

void mousePress(int button, int state, int x, int y)
{
	switch (button)
	{
	case GLUT_LEFT_BUTTON:
		if (state == GLUT_DOWN)
		{
			//FUNKCIJA
		}
		break;
	case GLUT_RIGHT_BUTTON:
		if (state == GLUT_DOWN)
		{
			//FUNKCIJA
		}
		break;
	default:
		break;
	}
}

void keyPress(unsigned char key, int x, int y)
{


	switch (key)
	{
	case 27: //ESC key
		exit(0);
		break;
	case 'w':
		MoveForward();
		break;
	case 's':
		MoveBackward();
		break;
	case 'a':
		//FUNCTION
		MoveLeft();
		break;
	case 'd':
		//FUNCTION
		MoveRight();
		break;
	case 'u':
		SpeedUp();
		break;
	case 'j':

		SpeedDown();
		break;
	case 52:

		TurnLeft();
		break;
	case 54:

		TurnRight();
		break;
	case 50:
		TurnDown();
		break;
	case 56:
		TurnUp();
		break;
	}

}

/*--------------------------------------------------*/

int main(int argc, char** argv)
{
	glutInit(&argc, argv);

	glutInitDisplayMode(GLUT_DOUBLE | GLUT_DEPTH | GLUT_STENCIL);
	glutInitWindowSize(height * ratio, height);
	glutInitWindowPosition(150, 50);
	glutCreateWindow(title);
	createCoordinates();

	glutDisplayFunc(display);
	glutTimerFunc(100, timer, 0);
	glutReshapeFunc(reshape);

	glutMouseFunc(mousePress);
	glutKeyboardFunc(keyPress);

	initGL();
	glutMainLoop();

	return 0;
}