extern crate nalgebra_glm as glm;

use std::ffi::c_void;
use std::mem::offset_of;
use std::{fs::File, io::BufWriter};

use nexg::{
    Buffer, BufferDescriptor, BufferUsage, CommandPoolDescriptor, CommandRecorderDescriptor,
    DataFormat, Extent3d, FrameBuffer, FrameBufferDescriptor, Image, ImageDescriptor, ImageFormat,
    ImageViewDescriptor, InstanceBuilder, InstanceFeature, LoadOp, Pipeline, PipelineDescriptor,
    PipelineLayout, PipelineLayoutDescriptor, PipelineVertexInputDescriptor, QueueSubmitDescriptor,
    RenderPass, RenderPassBeginDescriptor, RenderPassDescriptor, RequestConnecterDescriptor,
    Resource, ResourceBufferDescriptor, ResourceLayout, ResourceLayoutBinding, ResourcePool,
    ResourcePoolDescriptor, ResourcePoolSize, ResourceType, ResourceUpdateDescriptor, Shader,
    ShaderStage, ShaderStageDescriptor, Spirv, StoreOp, SubPass, SubPassDescriptor,
    VertexInputAttributeDescriptor, VertexInputBindingDescriptor,
};
use png::text_metadata::ZTXtChunk;
use simple_logger::SimpleLogger;

const VERTEX_S: &'static [u8] = include_bytes!("shader/shader2.vert.spv");
const FRAGMENT_S: &'static [u8] = include_bytes!("shader/shader.frag.spv");

#[repr(C)]
#[derive(Clone, Copy, Debug)]
pub struct Vec4(f32, f32, f32, f32);
#[repr(C)]
#[derive(Clone, Copy, Debug)]
pub struct Vec2(f32, f32);
#[repr(C)]
#[derive(Clone, Copy, Debug)]
pub struct Vertex {
    pos: Vec4,
    color: Vec4,
}

struct SceneData {
    rect_center: Vec4,
}

const SCENE_DATA: SceneData = SceneData {
    rect_center: Vec4(0.3, -0.2, 0.0, 0.0),
};

const WIDTH: u32 = 640;
const HEIGHT: u32 = 480;

const VERTEX: [Vertex; 4] = [
    Vertex {
        pos: Vec4(-0.5, -0.5, 0.0, 0.0),
        color: Vec4(0.0, 0.0, 1.0, 1.0),
    },
    Vertex {
        pos: Vec4(0.5, 0.5, 0.0, 0.0),
        color: Vec4(0.0, 1.0, 0.0, 1.0),
    },
    Vertex {
        pos: Vec4(-0.5, 0.5, 0.0, 0.0),
        color: Vec4(1.0, 0.0, 0.0, 1.0),
    },
    Vertex {
        pos: Vec4(0.5, -0.5, 0.0, 0.0),
        color: Vec4(1.0, 1.0, 1.0, 1.0),
    },
];

const INDICES: [u16; 6] = [0, 1, 2, 1, 0, 3];

fn main() {
    SimpleLogger::new().init().unwrap();
    let feature = InstanceFeature::empty();
    let instance = InstanceBuilder::new().feature(feature).build().unwrap();
    let desc = RequestConnecterDescriptor::new()
        .graphic_support(true)
        .compute_support(true)
        .transfer_support(true);
    let connecters = instance.request_connecters(&[desc]).unwrap();
    let connecter = connecters[0];
    let index = connecter.get_queue_family_index();

    let device = connecter.create_device(&instance, index).unwrap();

    let queue = device.get_queue(index);
    let desc = CommandPoolDescriptor::empty().queue_family_index(index);
    let pool = device.create_command_pool(&desc).unwrap();
    let desc = CommandRecorderDescriptor::empty();
    let recorders = device.allocate_command_recorder(pool, &desc).unwrap();
    let desc = ImageDescriptor::new().extent(Extent3d::new(WIDTH, HEIGHT, 1));
    let image = Image::create(&instance, &device, connecter, &desc).unwrap();
    let desc = ImageViewDescriptor::empty().format(ImageFormat::R8G8B8A8Unorm);
    let image_view = image.create_image_view(&device, &desc);

    let vertex = Shader::new(&device, &Spirv::from_raw(VERTEX_S).unwrap());

    let fragment = Shader::new(&device, &Spirv::from_raw(FRAGMENT_S).unwrap());

    let desc = BufferDescriptor::empty().size(std::mem::size_of::<Vertex>() * VERTEX.len());
    let vertex_buffer = Buffer::new(&instance, connecter, &device, &desc).unwrap();
    vertex_buffer
        .write(&device, VERTEX.as_ptr() as *const c_void)
        .unwrap();
    vertex_buffer.lock(&device);
    let desc = BufferDescriptor::empty()
        .size(std::mem::size_of::<u16>() * INDICES.len())
        .usage(BufferUsage::Index);
    let index_buffer = Buffer::new(&instance, connecter, &device, &desc).unwrap();
    index_buffer
        .write(&device, INDICES.as_ptr() as *const c_void)
        .unwrap();
    index_buffer.lock(&device);
    let desc = BufferDescriptor::empty()
        .size(std::mem::size_of::<SceneData>())
        .usage(BufferUsage::Uniform);
    let uniform_buffer = Buffer::new(&instance, connecter, &device, &desc).unwrap();
    uniform_buffer
        .write(&device, &SCENE_DATA as *const SceneData as *const c_void)
        .unwrap();
    uniform_buffer.lock(&device);

    let resource_layout_bindings = vec![ResourceLayoutBinding::empty()
        .binding(0)
        .resource_type(ResourceType::UniformBuffer)
        .count(1)
        .shader_stage(ShaderStage::Vertex)];
    let resource_layout = ResourceLayout::new(&device, &resource_layout_bindings);
    let pool_sizes = vec![ResourcePoolSize::empty()];
    let pool_desc = ResourcePoolDescriptor::empty()
        .pool_sizes(&pool_sizes)
        .max_sets(1);
    let resource_pool = ResourcePool::new(&device, &pool_desc);
    let resource = Resource::allocate(&device, &resource_pool, &resource_layout);

    let buffer_desc = ResourceBufferDescriptor::new::<SceneData>(&uniform_buffer);
    let desc = vec![buffer_desc];
    let update_desc = ResourceUpdateDescriptor::new(&resource[0]).buffer_desc(&desc);
    device.update_resource(&update_desc);

    let desc = SubPassDescriptor::empty();
    let subpass = SubPass::new(connecter, &desc);
    let subpasses = &[subpass];
    let desc = RenderPassDescriptor::empty()
        .subpasses(subpasses)
        .load_op(LoadOp::Clear)
        .store_op(StoreOp::Store);
    let render_pass = RenderPass::new(&device, &desc).unwrap();
    let desc = PipelineLayoutDescriptor::empty()
        .render_pass(&render_pass)
        .resource(&resource_layout);
    let pipeline_layout = PipelineLayout::new(&device, &desc).unwrap();
    let shader_stages = vec![
        ShaderStageDescriptor::empty()
            .entry_point("main")
            .stage(ShaderStage::Vertex)
            .shaders(&vertex),
        ShaderStageDescriptor::empty()
            .entry_point("main")
            .stage(ShaderStage::Fragment)
            .shaders(&fragment),
    ];
    let binding_desc = vec![VertexInputBindingDescriptor::empty()
        .binding(0)
        .stride(std::mem::size_of::<Vertex>())];
    let attribute_desc = vec![
        VertexInputAttributeDescriptor::empty()
            .binding(0)
            .location(0)
            .format(DataFormat::R32G32SFloat)
            .offset(offset_of!(Vertex, pos)),
        VertexInputAttributeDescriptor::empty()
            .binding(0)
            .location(1)
            .format(DataFormat::R32G32B32SFloat)
            .offset(offset_of!(Vertex, color)),
    ];
    let vertex_input_desc = PipelineVertexInputDescriptor::empty()
        .attribute_desc(&attribute_desc)
        .binding_desc(&binding_desc);
    let desc = PipelineDescriptor::empty()
        .shader_stages(&shader_stages)
        .input_descriptor(&vertex_input_desc)
        .width(WIDTH)
        .height(HEIGHT);
    let pipeline = Pipeline::new(&device, pipeline_layout, &render_pass, &desc).unwrap();

    let desc = FrameBufferDescriptor::empty()
        .render_pass(&render_pass)
        .image_view(&image_view)
        .width(WIDTH)
        .height(HEIGHT);
    let framebuffer = FrameBuffer::new(&device, &desc).unwrap();

    let begin_desc = RenderPassBeginDescriptor::empty()
        .width(WIDTH)
        .height(HEIGHT)
        .clear(0.0, 0.0, 0.0, 1.0)
        .render_pass(&render_pass)
        .frame_buffer(&framebuffer);
    recorders[0].begin(&device, begin_desc);
    recorders[0].bind_pipeline(&device, &pipeline[0]);
    recorders[0].bind_vertex_buffer(&device, &vertex_buffer);
    recorders[0].bind_index_buffer(&device, &index_buffer);
    recorders[0].bind_resource(&device, &resource[0], &pipeline_layout);
    recorders[0].draw_indexed(&device, INDICES.len() as u32, 1, 0, 0, 0);
    recorders[0].end(&device);

    let desc = QueueSubmitDescriptor::empty();
    queue.submit(&device, &desc, &recorders);

    let file = File::create("descriptor.png").unwrap();
    let w = &mut BufWriter::new(file);

    let mut encoder = png::Encoder::new(w, WIDTH, HEIGHT); // Width is 2 pixels and height is 1.
    encoder.set_color(png::ColorType::Rgba);
    encoder.set_depth(png::BitDepth::Eight);
    // Adding text chunks to the header
    encoder
        .add_text_chunk(
            "Testing tEXt".to_string(),
            "This is a tEXt chunk that will appear before the IDAT chunks.".to_string(),
        )
        .unwrap();
    encoder
        .add_ztxt_chunk(
            "Testing zTXt".to_string(),
            "This is a zTXt chunk that is compressed in the png file.".to_string(),
        )
        .unwrap();
    encoder
        .add_itxt_chunk(
            "Testing iTXt".to_string(),
            "iTXt chunks support all of UTF8. Example: हिंदी.".to_string(),
        )
        .unwrap();

    let mut writer = encoder.write_header().unwrap();
    let slice = image.as_raw_data(&device, WIDTH, HEIGHT).unwrap();
    writer.write_image_data(&slice).unwrap(); // Save

    // We can add a tEXt/zTXt/iTXt at any point before the encoder is dropped from scope. These chunks will be at the end of the png file.
    let tail_ztxt_chunk = ZTXtChunk::new(
        "Comment".to_string(),
        "A zTXt chunk after the image data.".to_string(),
    );
    writer.write_text_chunk(&tail_ztxt_chunk).unwrap();
}