#pragma once
#ifndef _NB_CAMERA
#define _NB_CAMERA

#include <GLLoad.h>
#include <glm/glm.hpp>
#include <glm/gtc/matrix_inverse.hpp>
#include <glm/gtc/matrix_transform.hpp>
#include <glm/gtc/type_ptr.hpp>

namespace NB {

class Camera {
public:
    typedef glm::vec3 Vec3;
    typedef glm::mat4 Mat4;

    enum CameraTypeEnum : unsigned char {
        None,
        Orthographic,
        Perspective
    };

    const CameraTypeEnum CameraType = CameraTypeEnum::None;

    static Vec3 normCross(const Vec3&, const Vec3&);
    static Vec3 transformVec(const Mat4&, const Vec3&);

    Camera(
        const Vec3& pos=Vec3(1.0f, 0.0f, 0.0f),
        const Vec3& tar=Vec3(0.0f, 0.0f, 0.0f),
        const Vec3& up =Vec3(0.0f, 1.0f, 0.0f)
    );


    Vec3 getPos() const;
    Vec3 getTarget() const;
    Vec3 getDirection() const;
    Vec3 getWorldUp() const;
    Vec3 getUp() const;
    Vec3 getRight() const;
    Mat4 getLookMatrix() const;
    Mat4 getProjectionMatrix() const;
    Mat4 getFlattenedMatrices() const;
    bool isUpLocked() const;

    void setProjection(const Mat4&);
    void setPos(const Vec3&);
    void setTarget(const Vec3&);
    void setDirection(const Vec3&);
    void setWorldUp(const Vec3&);
    void lockToWorldUp(bool lock);
    void resetUp();
    void addPos(const Vec3&);
    void panPos(const Vec3&);
    void panPosRelative(const Vec3&);
    void addTarget(const Vec3&);
    void roll(float);
    void pitch(float);
    void yaw(float);

protected:
    Vec3 _pos;
    Vec3 _tar;
    Vec3 _dir;
    Vec3 _world_up;
    Vec3 _up;
    Vec3 _right;
    Mat4 _look;
    Mat4 _proj;
    bool _lock_world_up = true;
    
    void _calcLook();

};

class OrthographicCamera : public Camera {
public:
    const CameraTypeEnum CameraType = CameraTypeEnum::Orthographic;
    
    OrthographicCamera(
        const Vec3& pos=Vec3(1.0f, 0.0f, 0.0f),
        const Vec3& tar=Vec3(0.0f, 0.0f, 0.0f),
        const Vec3& up =Vec3(0.0f, 1.0f, 0.0f),
        float left = -1.0f,
        float right = 1.0f,
        float bottom = -1.0f,
        float top = 1.0f,
        float near = -1.0f,
        float far = 1.0f
    );

    float getLeftPlane() const;
    float getRightPlane() const;
    float getBottomPlane() const;
    float getTopPlane() const;
    float getNearPlane() const;
    float getFarPlane() const;

    void setLeftPlane(float);
    void setRightPlane(float);
    void setBottomPlane(float);
    void setTopPlane(float);
    void setNearPlane(float);
    void setFarPlane(float);

private:
    float _leftPlane, _rightPlane, _topPlane, _bottomPlane, _nearPlane, _farPlane;

    using Camera::setProjection;

};

class PerspectiveCamera : public Camera {
public:
    const CameraTypeEnum CameraType = CameraTypeEnum::Perspective;
    
    PerspectiveCamera(
        const Vec3& pos=Vec3(1.0f, 0.0f, 0.0f),
        const Vec3& tar=Vec3(0.0f, 0.0f, 0.0f),
        const Vec3& up =Vec3(0.0f, 1.0f, 0.0f),
        float fov = 45.0f,
        float aspectRatio = 1.0f,
        float near = -1.0f,
        float far = 1.0f
    );

private:
    float _fov, _ratio, _nearPlane, _farPlane;
    
    using Camera::setProjection; 

};

}
#endif // _NB_CAMERA