#ifndef SHADOWMAP_H_
#define SHADOWMAP_H_

#include <iostream>
#include <GL/GLee.h>

#include "../math/Vector.h"

/*
 * Basic shader
 *
 * Vertex (1):
        #version 150

        uniform mat4 pmv;

        in vec3 vertex0;

        void main(){
            gl_Position = pmv*vec4(vertex0, 1.0);
        }
 *
 * Vertex (2):
        #version 150

        uniform mat4 pmv;
        uniform mat4 shadowBP; // bias*projection
        uniform mat4 shadowMV;

        in vec3 vertex0;
        in vec2 texCoord0;

        out vec2 texCoord;
        out vec4 shadowCoord;

        void main(){
            texCoord = texCoord0;
            shadowCoord = shadowBP*shadowMV*vec4(vertex0, 1.0);
            gl_Position = pmv*vec4(vertex0, 1.0);
        }
 *
 * Fragment (1):
        #version 150

        precision highp float;

        void main(){
            gl_FragDepth = gl_FragCoord.z;
        }
 *
 * Fragment (2):
        #version 150

        precision highp float;

        uniform sampler2D texture0;
        uniform sampler2DShadow shadowMap;

        in vec2 texCoord;
        in vec4 shadowCoord;

        void main(){
            vec4 SC = shadowCoord/shadowCoord.w+0.0005;

            float D = textureProj(shadowMap, SC);

            float shadow = 1.0;

            if(shadowCoord.w > 0.0){
                if(D < SC.z){
                    shadow = 0.5;
                }
            }

            gl_FragColor = shadow*texture(texture0, texCoord);
        }
 *
 */

class ShadowMap{
    protected:
        GLuint m_texture;
        GLuint m_fbo; // Frame Buffer Object
        vec2 m_size;
        vec2 m_pixelOffset; // Persistent Closing Filter

    public:
        ShadowMap(vec2 size, vec2 pixelOffset);
        virtual ~ShadowMap();

        void updateTexture(vec2 v);
        void updateTexture(float x, float y);
        void setPixelOffset(vec2 v);
        void setPixelOffset(float x, float y);

        GLuint getTextureID();
        GLuint getFBO();

        vec2 getTextureSize();
        float getTextureWidth();
        float getTextureHeight();

        vec2 getPixelOffset();
};

#endif