#![forbid(unsafe_code)]
use crate::error::*;
use crate::linear_algebra::{ Vec2, Vec3 };
use crate::shader_data::Vertex;

use std::io::Cursor;

use tobj::{ load_obj_buf, LoadOptions };


pub fn load_model() -> Result<(Vec<Vertex<f32>>, Vec<u32>)> {
  let obj = include_bytes!("../models/teapot.obj");

  let load_options = LoadOptions {
    single_index: true,
    triangulate: true,
    ..Default::default()
  };
  let (models, materials) = load_obj_buf(&mut Cursor::new(obj), &load_options,
                                         |_| Ok(Default::default()))?;

  let _ = materials?;

  let mut vertices = Vec::new();
  let mut indices = Vec::new();

  for model in models {
    for index in 0 .. model.mesh.positions.len() / 3 {
      vertices.push(Vertex::new(Vec3::new(model.mesh.positions[index*3],
                                          model.mesh.positions[index*3 + 1],
                                          model.mesh.positions[index*3 + 2]),
                                Vec3::new(1.0, 1.0, 1.0),
                                Vec2::new(model.mesh.texcoords[index*2],
                                          model.mesh.texcoords[index*2 + 1])))
    }

    for index in model.mesh.indices {
      indices.push(index);
    }
  }

  Ok((vertices, indices))
}