#ifndef GLAD
#define GLAD
#include <glad/glad.h>
#endif

#include <GLFW/glfw3.h>
#include <vector>

#include "font.hpp"
#include "text.hpp"
#include "shader.hpp"
#include "math.h"
#include "font/metadata.hpp"

Text::Text(){}

//makes the text fit in a rectangle
Text::Text(const char* s,Rectangle rectangle, float screenRatio):
	Text{s, CENTER, rectangle.height, rectangle.width,
			rectangle.x+rectangle.width/2,
			rectangle.y+rectangle.height/2,screenRatio
			}
{
}
Text::Text(Positioning positioning,float maxHeight,float maxWidth,float
		xPos, float yPos,float screenRatio,const char* s):
	Text{s,positioning, maxHeight, maxWidth, xPos, yPos, screenRatio}
{
}
Text::Text(const char* s,Positioning positioning,float maxHeight,float maxWidth,float
		xPos, float yPos,float screenRatio){
	glGenVertexArrays(1,&VAO);
	glGenBuffers(1,&VBO);
	glGenBuffers(1,&EBO);
	
	glBindVertexArray(VAO);
	
	glBindBuffer(GL_ARRAY_BUFFER,VBO);
	glBindBuffer(GL_ELEMENT_ARRAY_BUFFER,EBO);

	glVertexAttribPointer(0,2,GL_FLOAT, GL_FALSE, 4*sizeof(float),NULL);
	glEnableVertexAttribArray(0);
	glVertexAttribPointer(1,2,GL_FLOAT, GL_FALSE, 4*sizeof(float),(void*)(2*sizeof(float)));
	glEnableVertexAttribArray(1);

	std::vector<float> vertices;
	std::vector<unsigned int> indices;

	float x=0.0f;

	for(int i =0; s[i]!='\0'; i++){
		char c = s[i];
		float y_top = (float)characterMeta[c].bearingY/16.0;
		float y_bottom = y_top-(float)characterMeta[c].sizeY/16.0;
		float sizeX= (float)characterMeta[c].sizeX;
		float sizeY= (float)characterMeta[c].sizeY;
		vertices.insert(vertices.end(),{
			(float)x,	y_top,		(c%16)/16.0f,	(c/16)/8.0f,
			(float)x,	y_bottom,		(c%16)/16.0f,	(c/16+sizeY/16.0f)/8.0f,
			(float)x+sizeX/16.0f,	y_bottom, 		(c%16+sizeX/16.0f)/16.0f,	(c/16+sizeY/16.0f)/8.0f,
			(float)x+sizeX/16.0f,	y_top,		(c%16+sizeX/16.0f)/16.0f,	(c/16)/8.0f
		});

		unsigned int s = vertices.size()/4-4;
		indices.insert(indices.end(), {
			s+0,s+1,s+2,
			s+0,s+2,s+3
		});
		x+= ((float)(characterMeta[c].Advance>>6))/16.0;
	}

	glBindBuffer(GL_ARRAY_BUFFER, VBO);
	glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, EBO);
	glBufferData(GL_ARRAY_BUFFER, vertices.size()*sizeof(float), &vertices[0], GL_STATIC_DRAW);
	glBufferData(GL_ELEMENT_ARRAY_BUFFER, indices.size()*sizeof(unsigned int), &indices[0], GL_STATIC_DRAW);
	amElements= indices.size();

	float width,height;	
	//Check if width is not too big
	if(maxHeight*x *screenRatio< maxWidth){
		height= maxHeight;
		width = maxHeight*x*screenRatio;
	}else{
		height= maxWidth/x/screenRatio;
		width = maxWidth;
	}

	transform.M[0][0]=width/x;
	transform.M[1][1]=height;

	switch(positioning){
		case(LEFT_BOTTOM):
			transform.M[0][3]=xPos;
			transform.M[1][3]=yPos;
			break;
		case(CENTER):
			transform.M[0][3]=xPos-width/2;
			transform.M[1][3]=yPos-height/2;
	}
}

void Text::Delete(){
	glDeleteVertexArrays(1,&VAO);
	glDeleteBuffers(1,&VBO);
}

void Text::Draw(){
	this->shader.activate();
	this->shader.setUniformMat4("transform",transform);
	
	glBindTexture(GL_TEXTURE_2D,this->texture);
	glBindVertexArray(VAO);
	glBindBuffer(GL_ELEMENT_ARRAY_BUFFER,EBO);
	glDrawElements(GL_TRIANGLES,amElements,GL_UNSIGNED_INT,0);
}

void Text::initFont(){
	texture =createTexture("font/combined.png");
	shader = Shader("shaders/text.vs","shaders/text.fs");
}