use eatgel::buffer::StaticBufferNonIndexed;
use eatgel::shader::{Shader, ShaderProgram, ShaderType};
use eatgel::texture::{Image, ImageFormat, Texture, TextureSlot};
use eatgel::{GlContext, ShaderData, UpdateUniform, VertexData};
use glfw::ffi::glfwGetTime;
use glfw::{
    flush_messages, Action, Callback, Context, Glfw, Key, OpenGlProfileHint, SwapInterval, Window,
    WindowEvent, WindowHint, WindowMode,
};
use nalgebra_glm as glm;
use nalgebra_glm::{one, vec2, vec3, zero, Mat4, Vec2, Vec3};
use std::io::Cursor;

#[derive(ShaderData)]
struct Simple {
    model: Mat4,
    view: Mat4,
    projection: Mat4,
    our_texture: TextureSlot,
}

#[derive(VertexData)]
struct Vertex {
    position: Vec3,
    uv: Vec2,
}

impl Default for Simple {
    fn default() -> Self {
        Simple {
            model: zero(),
            view: zero(),
            projection: zero(),
            our_texture: TextureSlot::Slot0,
        }
    }
}

impl Simple {
    pub fn new() -> Self {
        Self::default()
    }
}

struct State {
    shader_program: ShaderProgram<Simple>,
    texture: Texture,
    context: GlContext,
    object: StaticBufferNonIndexed,
    size: (i32, i32),
}

fn init(mut context: GlContext, window: &Window) -> State {
    let vertex_shader = Shader::compile(
        ShaderType::Vertex,
        include_str!("../shaders/simple_vertex.glsl"),
    )
    .expect("Failed to compile vertex shader");
    let fragment_shader = Shader::compile(
        ShaderType::Fragment,
        include_str!("../shaders/simple_fragment.glsl"),
    )
    .expect("Failed to compile fragment shader");

    let mut shader_program =
        ShaderProgram::create_with_data(Simple::new(), vertex_shader, fragment_shader)
            .expect("Failed create shader program");

    let vertices = vec![
        Vertex {
            position: vec3(-0.5, -0.5, -0.5),
            uv: vec2(0.0, 0.0),
        },
        Vertex {
            position: vec3(0.5, -0.5, -0.5),
            uv: vec2(1.0, 0.0),
        },
        Vertex {
            position: vec3(0.5, 0.5, -0.5),
            uv: vec2(1.0, 1.0),
        },
        Vertex {
            position: vec3(0.5, 0.5, -0.5),
            uv: vec2(1.0, 1.0),
        },
        Vertex {
            position: vec3(-0.5, 0.5, -0.5),
            uv: vec2(0.0, 1.0),
        },
        Vertex {
            position: vec3(-0.5, -0.5, -0.5),
            uv: vec2(0.0, 0.0),
        },
        Vertex {
            position: vec3(-0.5, -0.5, 0.5),
            uv: vec2(0.0, 0.0),
        },
        Vertex {
            position: vec3(0.5, -0.5, 0.5),
            uv: vec2(1.0, 0.0),
        },
        Vertex {
            position: vec3(0.5, 0.5, 0.5),
            uv: vec2(1.0, 1.0),
        },
        Vertex {
            position: vec3(0.5, 0.5, 0.5),
            uv: vec2(1.0, 1.0),
        },
        Vertex {
            position: vec3(-0.5, 0.5, 0.5),
            uv: vec2(0.0, 1.0),
        },
        Vertex {
            position: vec3(-0.5, -0.5, 0.5),
            uv: vec2(0.0, 0.0),
        },
        Vertex {
            position: vec3(-0.5, 0.5, 0.5),
            uv: vec2(1.0, 0.0),
        },
        Vertex {
            position: vec3(-0.5, 0.5, -0.5),
            uv: vec2(1.0, 1.0),
        },
        Vertex {
            position: vec3(-0.5, -0.5, -0.5),
            uv: vec2(0.0, 1.0),
        },
        Vertex {
            position: vec3(-0.5, -0.5, -0.5),
            uv: vec2(0.0, 1.0),
        },
        Vertex {
            position: vec3(-0.5, -0.5, 0.5),
            uv: vec2(0.0, 0.0),
        },
        Vertex {
            position: vec3(-0.5, 0.5, 0.5),
            uv: vec2(1.0, 0.0),
        },
        Vertex {
            position: vec3(0.5, 0.5, 0.5),
            uv: vec2(1.0, 0.0),
        },
        Vertex {
            position: vec3(0.5, 0.5, -0.5),
            uv: vec2(1.0, 1.0),
        },
        Vertex {
            position: vec3(0.5, -0.5, -0.5),
            uv: vec2(0.0, 1.0),
        },
        Vertex {
            position: vec3(0.5, -0.5, -0.5),
            uv: vec2(0.0, 1.0),
        },
        Vertex {
            position: vec3(0.5, -0.5, 0.5),
            uv: vec2(0.0, 0.0),
        },
        Vertex {
            position: vec3(0.5, 0.5, 0.5),
            uv: vec2(1.0, 0.0),
        },
        Vertex {
            position: vec3(-0.5, -0.5, -0.5),
            uv: vec2(0.0, 1.0),
        },
        Vertex {
            position: vec3(0.5, -0.5, -0.5),
            uv: vec2(1.0, 1.0),
        },
        Vertex {
            position: vec3(0.5, -0.5, 0.5),
            uv: vec2(1.0, 0.0),
        },
        Vertex {
            position: vec3(0.5, -0.5, 0.5),
            uv: vec2(1.0, 0.0),
        },
        Vertex {
            position: vec3(-0.5, -0.5, 0.5),
            uv: vec2(0.0, 0.0),
        },
        Vertex {
            position: vec3(-0.5, -0.5, -0.5),
            uv: vec2(0.0, 1.0),
        },
        Vertex {
            position: vec3(-0.5, 0.5, -0.5),
            uv: vec2(0.0, 1.0),
        },
        Vertex {
            position: vec3(0.5, 0.5, -0.5),
            uv: vec2(1.0, 1.0),
        },
        Vertex {
            position: vec3(0.5, 0.5, 0.5),
            uv: vec2(1.0, 0.0),
        },
        Vertex {
            position: vec3(0.5, 0.5, 0.5),
            uv: vec2(1.0, 0.0),
        },
        Vertex {
            position: vec3(-0.5, 0.5, 0.5),
            uv: vec2(0.0, 0.0),
        },
        Vertex {
            position: vec3(-0.5, 0.5, -0.5),
            uv: vec2(0.0, 1.0),
        },
    ];

    /*let data: &[f32] = &[
        -0.5, -0.5, -0.5, 0.0, 0.0, 0.5, -0.5, -0.5, 1.0, 0.0, 0.5, 0.5, -0.5, 1.0, 1.0, 0.5, 0.5,
        -0.5, 1.0, 1.0, -0.5, 0.5, -0.5, 0.0, 1.0, -0.5, -0.5, -0.5, 0.0, 0.0, -0.5, -0.5, 0.5,
        0.0, 0.0, 0.5, -0.5, 0.5, 1.0, 0.0, 0.5, 0.5, 0.5, 1.0, 1.0, 0.5, 0.5, 0.5, 1.0, 1.0, -0.5,
        0.5, 0.5, 0.0, 1.0, -0.5, -0.5, 0.5, 0.0, 0.0, -0.5, 0.5, 0.5, 1.0, 0.0, -0.5, 0.5, -0.5,
        1.0, 1.0, -0.5, -0.5, -0.5, 0.0, 1.0, -0.5, -0.5, -0.5, 0.0, 1.0, -0.5, -0.5, 0.5, 0.0,
        0.0, -0.5, 0.5, 0.5, 1.0, 0.0, 0.5, 0.5, 0.5, 1.0, 0.0, 0.5, 0.5, -0.5, 1.0, 1.0, 0.5,
        -0.5, -0.5, 0.0, 1.0, 0.5, -0.5, -0.5, 0.0, 1.0, 0.5, -0.5, 0.5, 0.0, 0.0, 0.5, 0.5, 0.5,
        1.0, 0.0, -0.5, -0.5, -0.5, 0.0, 1.0, 0.5, -0.5, -0.5, 1.0, 1.0, 0.5, -0.5, 0.5, 1.0, 0.0,
        0.5, -0.5, 0.5, 1.0, 0.0, -0.5, -0.5, 0.5, 0.0, 0.0, -0.5, -0.5, -0.5, 0.0, 1.0, -0.5, 0.5,
        -0.5, 0.0, 1.0, 0.5, 0.5, -0.5, 1.0, 1.0, 0.5, 0.5, 0.5, 1.0, 0.0, 0.5, 0.5, 0.5, 1.0, 0.0,
        -0.5, 0.5, 0.5, 0.0, 0.0, -0.5, 0.5, -0.5, 0.0, 1.0,
    ];*/
    let _indices: &[u32] = &[0, 1, 3, 1, 2, 3];

    let object = context.create_static_buffer_non_indexed(vertices);
    let bytes = Cursor::new(include_bytes!("../res/eater.png").to_vec());

    shader_program.init(&mut context);

    State {
        shader_program,
        context,
        object,
        texture: Image::load(bytes, ImageFormat::Png)
            .expect("Failed to load image")
            .into_texture(Default::default())
            .expect("Failed to load as texture"),
        size: window.get_size(),
    }
}

fn render(state: &mut State, _glfw: &mut Glfw) {
    let gl = &state.context;
    let shader = &mut state.shader_program;
    let texture = &state.texture;

    gl.clear();

    shader.enable();
    texture.enable(TextureSlot::Slot0);
    shader.our_texture = TextureSlot::Slot0;

    let model = one::<Mat4>();
    let _model = glm::rotate(&model, -55.0f32.to_radians(), &vec3(1.0f32, 0.0f32, 0.0f32));

    let view = one::<Mat4>();
    let view = glm::translate(&view, &vec3(0.0f32, 0.0f32, -3.0f32));

    let projection: Mat4 = glm::perspective(45.0f32.to_radians(), 1.0, 0.1, 100.0);

    /*let camera_pos: Vec3 = vec3(0.0, 0.0, 3.0);
    let camera_target: Vec3 = vec3(0.0, 0.0, 0.0);
    let camera_sub: Vec3 = camera_pos - camera_target;
    let camera_direction: Vec3 = glm::normalize::<f32, U3>(&camera_sub);

    let up = vec3(0.0, 1.0, 0.0);
    let camera_right = glm::normalize(&glm::cross(&up, &camera_direction));
    let camera_up = glm::cross(&camera_direction, &camera_right);

    let view = glm::look_at(
        &vec3(0.0, 0.0, 0.3),
        &vec3(0.0, 0.0, 0.0),
        &vec3(0.0, 0.1, 0.0),
    );*/

    // let trans = one::<Mat4>();
    // let trans = glm::translate(&trans, &vec3(0.5, -0.5, 0.0f32));

    unsafe {
        gl::Enable(gl::MULTISAMPLE);
    }

    let translates = &[
        glm::vec3(0.0, 0.0, 0.0),
        glm::vec3(2.0, 5.0, -15.0),
        glm::vec3(-1.5, -2.2, -2.5),
        glm::vec3(-3.8, -2.0, -12.3),
        glm::vec3(2.4, -0.4, -3.5),
        glm::vec3(-1.7, 3.0, -7.5),
        glm::vec3(1.3, -2.0, -2.5),
        glm::vec3(1.5, 2.0, -2.5),
        glm::vec3(1.5, 0.2, -1.5),
        glm::vec3(-1.3, 1.0, -1.5),
    ];

    shader.view = view;
    shader.projection = projection;

    let time = unsafe { glfwGetTime() } as f32;
    let radius = 10.0;
    let cam_x = time.sin() * radius;
    let cam_z = time.cos() * radius;

    shader.view = glm::look_at(
        &vec3(cam_x, 0.0, cam_z),
        &zero::<Vec3>(),
        &vec3(0.0, 1.0, 0.0),
    );

    for i in 0..translates.len() {
        let model = one::<Mat4>();
        let model = glm::translate(&model, &translates[i]);
        let angle = i as f32 * 20f32;
        let model = glm::rotate(
            &model,
            unsafe { glfwGetTime() } as f32 * 50.0f32.to_radians(),
            &vec3(0.5, 1.0, 0.0),
        );
        shader.model = glm::rotate(&model, angle, &vec3(1.0f32, 0.3f32, 0.5f32));
        shader.apply(&gl);
        state.object.draw();
    }
}

fn main() {
    let mut glfw = glfw::init::<()>(Some(Callback {
        f: |err, err_str, _| {
            println!("{:?}: {:?}", err, err_str);
        },
        data: (),
    }))
    .expect("Failed to init GLFW");

    glfw.window_hint(WindowHint::ContextVersion(3, 3));
    glfw.window_hint(WindowHint::OpenGlProfile(OpenGlProfileHint::Core));
    glfw.window_hint(WindowHint::Samples(Some(4)));

    let (mut window, events) = glfw
        .create_window(500, 500, "T̶ R҉ I͜ A ͢N ͠G L̷ E̷", WindowMode::Windowed)
        .expect("Failed to create window");

    window.make_current();
    window.set_key_polling(true);

    glfw.set_swap_interval(SwapInterval::Adaptive);

    let context = GlContext::new(|x| window.get_proc_address(x));

    let mut state = init(context, &window);

    unsafe {
        gl::Viewport(0, 0, state.size.0, state.size.1);
        gl::Enable(gl::DEPTH_TEST);
    }
    // let mut time = Instant::now();
    // println!("0");
    while !window.should_close() {
        let (width, height) = window.get_size();

        if state.size != (width, height) {
            unsafe { gl::Viewport(0, 0, width, height) }
        }

        state.size = (width, height);

        render(&mut state, &mut glfw);

        window.swap_buffers();
        glfw.poll_events();
        for (_, event) in flush_messages(&events) {
            if let WindowEvent::Key(key, _, Action::Release, _) = event {
                if key == Key::Escape || key == Key::Q {
                    window.set_should_close(true);
                }
            }
        }
        //
        // let new_time = Instant::now();
        // println!(
        //     "\x1B[1A\x1B[Kfps: {}",
        //     (1.0 / (new_time - time).as_secs_f64()).floor()
        // );
        //
        // time = new_time;
    }

    window.close();
}