#include <exception>
#include <iostream>
#include <string>
#include <glew.h>
#include <GL/glfw.h>
#include <iterator>
#include "../include/TextRenderer.h"
#include <ft2build.h>
#include FT_FREETYPE_H
#include <stdexcept>
#include <freetype/ftglyph.h>


using std::runtime_error;
using std::cout;
TextRenderer::TextRenderer(float x,float y, FT_Face Face,std::string s)
{


    FT_Set_Char_Size(
        Face,    /* handle to face object           */
        0,       /* char_width in 1/64th of points  */
        16*64,   /* char_height in 1/64th of points */
        0,     /* horizontal device resolution    */
        0 );   /* vertical device resolution      */
    slot= Face->glyph;

    text=s;
    setsx(x);
    setsy(y);
    penX=x;
    penY=y;
    face=Face;
    //shaders
    GLuint v = glCreateShader(GL_VERTEX_SHADER) ;
    const char* vs = "void main(){	gl_Position = ftransform();gl_TexCoord[0]=gl_MultiTexCoord0;}";
    glShaderSource(v,1,&vs,NULL);
    glCompileShader(v);
    GLuint f = glCreateShader(GL_FRAGMENT_SHADER) ;
    const char* fs = "uniform sampler2D texture1; void main() {    gl_FragColor = texture2D(texture1, gl_TexCoord[0].st); }";
    glShaderSource(f,1,&fs,NULL);
    glCompileShader(f);
     Program= glCreateProgram();
    glAttachShader(Program,v);
    glAttachShader(Program,f);
    glLinkProgram(Program);


}
void TextRenderer::render()
{
glUseProgram(Program);


    FT_UInt  glyph_index;
    for ( int n = 0; n < text.size(); n++ )
    {



        /* retrieve glyph index from character code */

        glyph_index = FT_Get_Char_Index( face, text[n] );

        /* load glyph image into the slot (erase previous one) */
        error = FT_Load_Glyph( face, glyph_index, FT_LOAD_RENDER );


        draw(&face->glyph->bitmap,penX + slot->bitmap_left,penY - slot->bitmap_top );


        penX += *(&face->glyph->bitmap.width)+3;
        penY += slot->advance.y >> 6; /* not useful for now */
    }



}
void TextRenderer::draw(FT_Bitmap * bitmap,float x,float y)
{



GLuint texture [1] ;
//crashes on next line
    glGenTextures(1,texture);
    glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
glTexParameteri (GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
glTexParameteri (GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glTexParameteri (GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_DECAL);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, bitmap->width, bitmap->rows, 0, GL_LUMINANCE, GL_UNSIGNED_BYTE, bitmap->buffer);//luminance vs gl_RED?


//    int loc = glGetUniformLocation(Program, "texture1");
//    glUniform1i(loc, 0);
glEnable(GL_BLEND);
glBindTexture(GL_TEXTURE_2D, texture[0]);
glEnable(GL_TEXTURE_2D);
        int height=bitmap->rows;
        int width=bitmap->width;
        glLoadIdentity();
glScalef(0.01f, 0.01f, 1.0f);
        glBegin(GL_QUADS);
        glTexCoord2f (0.0, 0.0);
        glVertex2f(x,y);
        glTexCoord2f (1.0, 0.0);
        glVertex2f(x+width,y);
        glTexCoord2f (1.0, 1.0);
       glVertex2f(x+width,y+height);
       glTexCoord2f (0.0, 1.0);
        glVertex2f(x,y+height);
       glEnd();
glDisable(GL_TEXTURE_2D);

}