extern crate clap;
extern crate glium;
#[macro_use]
extern crate verbose_log;
extern crate model_converter;

use std::process::exit;
use std::time::{Instant, Duration};

use clap::{App, Arg};

use glium::Display;
use glium::glutin;
use glium::glutin::{EventsLoop, WindowBuilder};

use glium::glutin::Event;
use glium::glutin::WindowEvent;
use glium::glutin::VirtualKeyCode;

use model_converter::scene::Scene;
use model_converter::math::bounding_box::BoundingBox3;
use model_converter::math::vector::Vector3;
use model_converter::parser::parse_file;
use model_converter::renderer::Renderer;
use model_converter::controls::{OrbitControls, FirstPersonControls};
use model_converter::camera::Camera;

fn as_millis(duration: Duration) -> u64 {
    duration.as_secs() * 1_000 + (duration.subsec_nanos() as u64) / 1_000_000
}

fn main() {

    let matches = App::new("3D Viewer")
        .version("1.0")
        .arg(Arg::with_name("input")
             .short("i")
             .long("input")
             .value_name("FILES")
             .takes_value(true)
             .multiple(true)
             .help("Input model files")
             .required(true))
        .arg(Arg::with_name("first person")
             .short("f")
             .long("first-person")
             .help("Uses first person controls instead of orbit controls"))
        .arg(Arg::with_name("verbose")
             .short("v")
             .long("verbose")
             .help("Shows logs during the parsing of the model"))
        .get_matches();

    // Set verbose flag
    verbose_log::log::VERBOSE.with(|verbose| {
        *verbose.borrow_mut() = matches.occurrences_of("verbose") > 0;
    });

    use std::f64::{MIN, MAX};
    let mut bbox = BoundingBox3::new(
        Vector3::new(MAX, MAX, MAX),
        Vector3::new(MIN, MIN, MIN),
    );

    let mut models = vec![];

    for input in matches.values_of("input").unwrap() {
        match parse_file(&input) {
            Ok(model) => {
                if model.vertices.len() > 0 {
                    bbox = bbox.union(&model.bounding_box());
                }
                models.push((input.to_owned(), model))
            },
            Err(e) => {
                eprintln!("Error while parsing file: {}", e);
                exit(1);
            },
        }
    }

    let mut events_loop = EventsLoop::new();
    let window = WindowBuilder::new().with_visibility(false);
    let context = glutin::ContextBuilder::new().with_depth_buffer(24);
    let display = Display::new(window, context, &events_loop).unwrap();
    let mut renderer = Renderer::new(display);

    let mut scene = Scene::new();
    let mut before;
    let mut duration;

    for (name, mut model) in models {
        log!("Scaling model {}...", name);
        model.center_and_scale_from_box(&bbox);

        log!("\nBuilding textures for model {}...", name);

        before = Instant::now();
        model.build_textures(&renderer);
        duration = Instant::now().duration_since(before);

        log!(" done in {}ms.\nBuilding vertex buffers for model {}...",
             as_millis(duration) ,name);

        before = Instant::now();
        model.build_vertex_buffers(&renderer);
        duration = Instant::now().duration_since(before);

        scene.emplace(model);
        logln!(" done in {}ms.\nFinished", as_millis(duration));
    }

    let mut closed = false;

    let mut camera = Camera::new(
        Vector3::new( 0.0, 0.0, 0.0),
        Vector3::new( 0.0, 0.0, 0.0),
        Vector3::new( 0.0, 1.0, 0.0),
    );

    camera.z_near = 0.0001;

    let mut controls: Box<Controls> = if matches.is_present("first person") {
        Box::new(FirstPersonControls::new())
    } else {
        Box::new(OrbitControls::new(
            Vector3::new(0.0, 0.0, 0.0),
            1.0,
            &mut camera
        ))
    };

    renderer.show();

    use model_converter::controls::Controls;
    while !closed {

        events_loop.poll_events(|ev| {

            controls.manage_event(&ev, &mut camera, &renderer);

            match ev {
                // Close window
                Event::WindowEvent {
                    event: WindowEvent::Closed, ..
                } => closed = true,

                // Escape key
                Event::WindowEvent {
                    event: WindowEvent::KeyboardInput {
                        input: glutin::KeyboardInput {
                            virtual_keycode: Some(VirtualKeyCode::Escape), ..
                        }, ..
                    }, ..
                } => closed = true,

                _ => (),
            }
        });

        controls.update(&mut camera, &renderer);
        renderer.render(&scene, &camera);

    }
}