#include "mesh.hpp"
#include "dbc.hpp"

void Mesh::draw(Shader &shader) {
  glBindVertexArray(VAO);
  glDrawElements(GL_TRIANGLES, indices.size(), GL_UNSIGNED_INT, 0);
  glBindVertexArray(0);
  glActiveTexture(GL_TEXTURE0);
}

void Mesh::connect_shader(const Shader& shader) {
  for(unsigned int i = 0; i < textures.size(); i++) {
    Texture& texture = textures[i];
    glActiveTexture(GL_TEXTURE0 + i);

    // move this to setup_mesh
    glUniform1i(texture.uniform_id, i);
    glBindTexture(GL_TEXTURE_2D, texture.id);

    texture.uniform_id = glGetUniformLocation(shader.ID, texture.target.c_str());
  }
}

void Mesh::setup_mesh() {
  glGenVertexArrays(1, &VAO);
  glGenBuffers(1, &VBO);
  glGenBuffers(1, &EBO);

  glBindVertexArray(VAO);
  glBindBuffer(GL_ARRAY_BUFFER, VBO);
  glBufferData(GL_ARRAY_BUFFER, vertices.size() * sizeof(Vertex), vertices.data(), GL_STATIC_DRAW);

  glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, EBO);
  glBufferData(GL_ELEMENT_ARRAY_BUFFER, indices.size() * sizeof(unsigned int), indices.data(), GL_STATIC_DRAW);

  // this matches the locations in the vertex shader
  glEnableVertexAttribArray(0);
  glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, sizeof(Vertex), (void*)offsetof(Vertex, position));

  glEnableVertexAttribArray(1);
  glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, sizeof(Vertex), (void*)offsetof(Vertex, normal));

  glEnableVertexAttribArray(2);
  glVertexAttribPointer(2, 2, GL_FLOAT, GL_FALSE, sizeof(Vertex), (void*)offsetof(Vertex, tex_coords));
}